Browsing by Subject "China"

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Approaches to improve the implementation and expansion of Miscanthus production
(2016) Xue, Shuai; Lewandowski, Iris
Several species within the miscanthus genus (Miscanthus spp.) are characterized by high biomass yields and low production input requirements. This raised increasing interests in their applications for bioenergy. However, to date, only small areas of Miscanthus × giganteus (approximately 40,000 ha) are commercially grown and used for generating electricity and heat in Europe, where miscanthus has been developed as bioenergy crop for more than decade. Reviewing state-of-the-art revealed four main factors limiting the implementation of miscanthus production. These are inefficient and expensive propagation techniques, land use dilemma (i.e. lack of land available for growing miscanthus), lack of varieties/genotypes adapted to various and especially to stressful environmental conditions and lack of efficient agronomic practices for miscanthus establishment. Against these limiting factors, this thesis aims to (1) evaluate the different propagation systems with regard to technologies and costs, and improve the preferred rhizome propagation techniques; (2) address the land use dilemma through exploring marginal land (i.e. non-arable land with ability to grow plants with tolerance to environmental stresses) for miscathus production; (3) and screen optimal genotypes and effective practices for establishing and managing miscanthus on marginal land in a case study on grassland. To achieve the first objective, a review, our own field trials and farmer surveys were performed. Direct seed sowing was found to be the cheapest propagation method (1,508.5 € ha-1 overall establishment costs) and micro-propagation the most expensive (6,320.8 € ha-1). Direct rhizome planting is the farmers’ most preferred and most applied establishment method and has moderate establishment cost of 1,904-3,375.7 € ha-1. However, it goes along with the lowest propagation efficiency (1:10) and consequently restricts the availability of propagation material for large-scale plantations. However, the multiplication ratio can be increased by reducing the rhizome size. Field trial results showed that 6-cm length is close to the minimum size of rhizome that can germinate after directly planting into field. Compared to the traditionally used macro-rhizome, the multiplication ratio of the improved rhizome propagation (using 6-cm rhizomes) is tripled. In addition, the multiplication ratio can also be increased by transplanting rhizome- or stem-derived plantlets. However, due to higher labour and energy inputs required for the pre-growing of plantlets, their establishment cost reduction potential is limited, with estimated costs of 4,240.8-4,400.8 € ha-1. Direct seed sowing as the cheapest method is presently only possible for Miscanthus sinensis and not yet practical under German conditions. In addition, the seed-setting rate of M. sinensis is very low (0.0-28.7%) under the climatic conditions of south-west Germany, making commercial seeds production difficult. For all the propagation methods considered, more research efforts are still required to reduce the material production costs and simultaneously increase the multiplication ratio. For the second objective, the production potential of miscanthus on marginal land in China was assessed. Because China has limited agricultural land resources and its non-food bioenergy policy (it is only allowed to grow energy crops on marginal land) is adamant, there is a desideration for exploiting its marginal land potential. In this study, Geographic Information System (GIS) techniques, model simulation were adopted to identify the productive marginal areas for miscanthus and to estimate their biomass and bioenergy production potentials. The results show that in China there are large marginal land areas of 17,163.54 × 104 ha available for growing miscanthus. However, due to limitation by low winter temperatures and low precipitation levels in some areas, the total marginal area suitable for growing miscanthus is only 769.37 × 104 ha. The Monteith radiation yield model was used to determine the potential miscanthus yield in Chinese climatic conditions. The simulation gave the actual harvestable yield levels on arable land of 18.1-44.2 odt ha-1 yr-1. Taking the environmental stresses of marginal conditions into account an achievable miscanthus yield potential on marginal land of 2.1-32.4 odt ha-1 yr-1 was calculated (varying between different marginal land types). Based on these achievable yield levels, the total miscanthus production potential on the entire suitable marginal land areas is 13,521.7 × 104 odt yr-1; the corresponding bio-electricity generation and total greenhouse gas saving potentials are 183.9 TW h yr-1 and 21,242.4 × 104 t CO2 eq. yr-1, respectively. The spatial distribution of the suitable marginal areas shows that they are mainly concentrated in the central part of Northeast China and the Loess Plateau. Both regions are recommended as priority development zones for the Chinese miscanthus-based bioenergy industry. However, implementation of this huge marginal land potential is currently constrained by many barriers, e.g. concerns on potential ecological effects, competition for marginal land from other uses, lack of high yield varieties in marginal conditions. Lack of varieties with suitability to marginal conditions and efficient agronomic practices for the establishment on marginal land are the main barriers that limit using marginal land for miscanthus production. Therefore, stress tolerant varieties need to be selected and methods of effective establishment of miscanthus on marginal land need to be developed. Worldwide, grassland is the most important marginal land type because it has the largest terrestrial area and mild environmental stresses for growing energy crops (including miscanthus). However, it is undesirable or even legally prohibited to convert grassland into bioenergy cropland to avoid biodiversity loss and soil carbon being reduced by tilling practices. Hence, no-till establishment practices for miscanthus establishment and maintenance on grassland are investigated here under the third objectives. Our study demonstrates that miscanthus can be successfully cultivated on both good (nutrient-rich) and marginal (nutrient-poor) grassland using the proposed agronomic practices and an increased grassland productivity may be achieved through the establishment of suitable miscanthus genotypes. The recommended agronomic practices are summarized as following. Miscanthus genotypes with tall, thick shoots perform better than those with short, thin shoots. Better establishment is achieved when rhizome-derived plantlets are transplanted into pre-disturbed grassland. The grassland pre-disturbance of low vegetation cutting (5 cm) and herbicide spraying in narrow stripes is recommended for its beneficial effect on miscanthus establishment without significant negative effects on grassland productivity. Two harvests, one in late spring and one in late autumn, are optimal to achieve a high grassland yield. In this thesis, the limitation of the inefficient propagation technique was mitigated through minimizing the rhizome size and exploring the seeds propagation potential. The land-use dilemma was alleviated by exploring the marginal land production potential. Additionally, constrains of lack of genotypes and agronomic practices for the miscanthus establishment on marginal land were improved by field trials on grassland (the most important marginal land type with a huge potential).These results can improve the implementation and expansion of miscanthus production. However, in addition to constrains improved in this thesis, the miscanthus production is currently constrained by many other technical, economic and financial, social and political, environmental issues. It is unlikely that the implementation and expansion will achieve without mitigating these constrains. Further research and support should address these barriers in an integrate manner.
Die Aussenhandelspolitik der EU gegenüber China: "China-Bashing" ist keine rationale Basis für Politik
(2007) Belke, Ansgar; Spies, Julia
Mit der Verabschiedung einer handelspolitischen Strategie gegenüber China Ende Oktober 2006 richtet sich die Europäische Union (EU) in einem veränderten globalen Wettbewerbsumfeld neu aus. Erstmals wird mit dem Einsatz von Schutzmaßnahmen gedroht, sollte China die multilateralen Vereinbarungen der Welthandelsorganisation (World Trade Organization ? WTO) nicht vollständig umsetzen. Doch hat auch die EU ihre ?Hausaufgaben? in den vergangenen Jahren nicht immer erledigt. Auf die Einfuhrschwemme von Textilien und Bekleidung Anfang 2005 reagierte sie durch die Erhebung neuer Quoten. In diesem Papier argumentieren wir, dass nur eine reziproke Marktöffnung eine stabile Partnerschaft bedingt, bei der beide Seiten vom ohnehin nicht aufzuhaltenden Vormarsch Chinas profitieren können.
Chinese urbanites and the preservation of rare species in remote parts of the country : the example of Eaglewood
(2014) Pelz, Sonna; Langenberger, Gerhard; Frör, Oliver; Ahlheim, Michael
Based on a Contingent Valuation study in Shanghai we assess peoples willingness to contribute personally to the alleviation of environmental problems occurring in distant parts of the country. One split of our survey assessed Shanghai residents willingness to pay for the preservation of rainforest in Yunnan, while the other split referred to the willingness to pay for the preservation of a single plant species (i.e. eaglewood) growing in this rainforest. The objectives of this study were twofold. Firstly, we wanted to find out if people living in big Chinese cities like Shanghai take an interest in the environmental problems existing in some remote parts of the country and if they are willing to contribute personally to remedy these problems. Secondly, we wanted to learn more about the motivation behind this kind of empathy, if it exists. We were especially interested in the question if this empathy refers to the specific environmental problems we addressed in our surveys or if it is motivated more by a general feeling of obligation towards environmental issues.
Commute time and subjective well-being in urban China
(2015) Sousa-Poza, Alfonso; Nie, Peng
Using data from the 2010 China Family Panel Studies, this study investigates the association between commute time and subjective well-being in a sample of 16- to 65-year-old employees in urban China. We find evidence that a longer commute time is associated with lower levels of both life satisfaction and happiness, especially when the commute times are extreme (≥ 1 hour per day). A multiple mediation analysis further indicates that the relation between commute time and happiness is partially mediated by time spent on daily activities, particularly sleeping. We calculate the amount of income necessary to compensate an employee’s loss in well-being at approximately 82 yuan per hour of commute time, implying that, in urban China, the annual loss of well-being amounts to around 10 billion yuan.
Doing research in China : ein Einblick in die Kultur und Forschungslandschaft Chinas. - China-Kompetenz in Hohenheim
(2020) Klenk, Johannes; Schmidt, Alexander; Waschek, Franziska
Mit dieser Broschüre soll Wissenschaftlerinnen und Wissenschaftlern, die sich für Forschung in und mit China interessieren oder eventuell bereits ein konkretes Forschungsvorhaben mit Bezug zu China haben, einen Überblick über einige Themen geben werden, die aus der Sicht der Autoren für geplante Projekte mit chinesischen Partnerinnen und Partnern oder für Aufenthalte vor Ort relevant sind.
Economic analysis on the agro-environmental impacts of management and policy measures in the North China Plain
(2011) Kühl, Yannick; Zeddies, Jürgen
The increased use of agricultural inputs like fertilizers and pesticides led to wide-spread negative environmental impacts of agriculture in the North China Plain (NCP). The context of this research is that, due to continued growth of the population and the economy, the demand for agricultural products in China is gradually rising. However resources like land and water are scarce in China. Therefore new strategies need to be developed which do not put additional strains on the environment but meet the expected demand. The NCP is regarded as China?s most important agricultural region. This work aims at describing and discussing the environmental effects of agriculture in the NCP. The extent of these environmental impacts is presented. An essential part of this work is the in-depth description and analysis of the current cropping systems and farming practices, which is based on the findings a household survey. The central hypothesis of this work is that a change of the management systems is able to meet the production goals, to achieve a higher input-output efficiency and to reduce negative environmental impacts. Embedded in the objectives of this work, the main goals are the description of current agricultural practices and related negative environmental impacts, the definition of agro-environmental management and policy measures, impact analysis of management and policy measures and the development of suggestions for further research. The second chapter aims at introducing the background of this research, i.e. the environmental impacts of agriculture. Hereby the focus lies on the introduction of relevant and characteristic farming practices and on the related institutional setting. Then the processes of data acquisition and data handling for this work are described. The descriptive analysis presents the findings from a survey in July 2008; it aims at describing the characteristics of the surveyed farm households. Chapter 5 describes the methodologies which are applied for the analysis in this work. The first part describes the methodology of Linear Programming and its selection process. The second part explains the selection process for the integrated households. The last part describes the processes of environmental assessment by means of selected indicators. In chapter 6 the model is applied to simulate and analyze the selected households in changing scenarios. Each Scenario is described individually. Then the simulation results are presented and discussed. In chapter 7 possible strategies to reduce environmental impacts of farming in the NCP ? considering the objectives of this work: sustainability and food security ? are discussed. The discussion focuses on the two main problems in the research area: fertilization and water. The analysis showed that current farming practices in the research area are not sustainable and can, thus, threaten future food security in China. The dilemma of the research area is that intensive agricultural production cannot be reduced because high yields are needed to feed the growing demand from a (economically) growing population. Simultaneously high resource consumption and pollution from farming cannot continue as that could eventually result in irreversible damage to agriculture in the NCP and also threatens livelihoods. Finally strategic policy recommendations, characteristics of improved management practices and recommendations for further research are presented. These recommendations can play an important role in decision guiding for policy makers. After reviewing other studies in the NCP, it has to be concluded that this work represents one of the most comprehensive analysis of the agricultural practices in the Hebei province. It was demonstrated that management practices for maize and wheat exist which can result in higher input-output efficiency and which are economically more profitable ? especially production options which include intercropping of other crops or demand-driven fertilization and irrigation. The hypothesis was tested to be valid. The simulation of optimization options showed that economically more profitable production options exist. These optimized production options are characterized by a more efficient factor input (mainly water and fertilization) and resulting decreased environmental impacts. The policy of a premium for reduced water use resulted in the highest simulated increases of total contribution margins with simultaneously reduced negative environmental impacts. However the simulation also revealed that, in order to ensure food security, incentives for producing wheat should be provided as it is the economically least profitable main crop, but it has important functions for own consumption. The simulation also revealed that policies aimed at increasing output prices of the main crops (in combination with optimized production options) can result in total higher contribution margins and decreased negative environmental impacts and higher resource use efficiency. It should be noted that the optimum results did not integrate production options which the surveyed farmers are currently applying ? this indicates that current practices are not efficient. Many studies state that knowledge transfer systems and extension services in the NCP are deficient. The survey showed that the majority of the households did not have contact with the extension services, and, moreover, most of the households never received agricultural training. A knowledge transfer program can be an efficient tool to reduce environmental impacts of farming in the NCP. In addition specific recommendations and systems under considerations of socio-economic approaches have to be developed to improve knowledge transfer and services to farmers in the NCP. Appropriate decision support systems for efficient land use in the research area have to be developed. This study showed that laws and regulations regarding environmental impacts exist, but they are not reliably enforced. Many studies state that the current institutional framework for water management is inadequate and that it, thus, represents one of the causes for the overexploitation of water resources. Therefore the responsibilities should be clearly defined in order to be able to create incentives for saving water and to increase efficiencies. Furthermore, farmers? water rights are not secure and transparent. Therefore plans, based on scientific estimations for water supply and demand, are needed to clearly define and enforce water use rights. Besides clearly defined and enforced water use rights, also longer, enforced and secure land-use rights might facilitate the adoption of sustainable farming practices. Also the institutional set-up complicates the implementation of policies. Therefore institutional change with coordinated efforts is needed. Decentralized and regionalized administrations might increase the effectiveness of policies. In addition the institutional framework has to be updated to the specific requirements in the NCP. One of the main reasons for problems related to water management is that it represents a mostly unregulated resource in the NCP. The survey showed that fertilizer use is strongly varying, overuse and undersupply occur in the research area. The strongly varying and inadequate fertilizer applications endanger the sustainability of the agricultural systems in the NCP. Furthermore the organic matter contents in the soils are too low. The survey also revealed that the farmers in the research area are not informed about the quality of their soils. Integrated into knowledge transfer programs, providing opportunities for soil analysis to the local farmers could result in fertilization practices which are based on the nutrient contents of the soil and, thus, are more efficient. Structural development projects in the Chinese rural areas need to be continued, especially in the research are, to avoid a rural exodus. The living conditions in the rural areas ? in terms of income, education and health services ? are still not comparable with the conditions in urban areas. Chinese policy has to focus on stopping the further decline of the ground water tables. Furthermore a conscious water use and environmental awareness for all stakeholders has to be created in order to avoid that pollution or resource scarcity and misuse will further reduce agricultural production in the NCP. The social costs of further decreased agricultural production in the NCP would be unbearable.
Economic evaluation of nitrogen application in the North China Plain
(2008) Barning, Roland; Zeddies, Jürgen
Today, China had solved its long-standing problem of inadequate grain production, but there are two new targets for rural China. Firstly, one goal is rural development towards an improved income generation of rural households in order to slow down the increasing income disparity in China, especially between rural and urban residents. Secondly, decades of inefficient utilisation of resources and high consumption of materials led to overexploitation of water and land resources. Over-fertilisation and low nitrogen use efficiency are representative for the production system in the North China Plain, which is characterised by small-scale farm households who traditionally cultivate winter wheat and summer maize. This thesis is embedded in the Sino-German Research Training Group "Modeling Material Flows and Production Systems for Sustainable Resource Use in Intensified Crop Production in the North China Plain", a cooperation of the University of Hohenheim in Stuttgart and the Chinese Agricultural University in Beijing. The overall hypothesis of this project is that substantial changes in farming systems and management practices can reduce environmental pollution and at the same time stabilise or increase income of farmers. As a subproject, this thesis focuses on the identification and evaluation of applicable instruments for this goal. The final target of this thesis is the simulation of scenarios in order to estimate the impact of identified instruments on the nitrogen balance as well as on the net income of farm households. The literature review indicates that nitrogen application in the cultivation of wheat and maize in the North China Plain shows a broad variation. A considerable high share of farm households applies nitrogen input levels far beyond the crop demand. This situation raises the question, what do over-fertilising farm households have in common or in another way, which factors lead to nitrogen overuse. This question is the basis of the discussion on applicable instruments to reduce the described nitrogen overuse and finally the intended simulation approach. The analysis of impact factors on the nitrogen application level requires a broad analysis of the cultivation system, the farm household characteristics, and the income sources of the farm households. The descriptive results of the farm survey on 340 farm households in the North China Plain conducted in 2005 are presented in chapter 5. The farming system at the survey sites is characterised by farm households, who cultivate the wheat and maize rotation system. In most cases, it is extended by cash crops such as cotton or peanuts. The farm size is on average 0.5 ha of allocated farmland per farm household. About two thirds of the farm households have some kind of additional off-farm income source, which usually exceeds the income share from farming. Farm households without off-farm income sources generate only half of the average farm household income. The average farm household income reaches 10 150 ¥ (1 015 ?) per year, but there is a broad variation within the survey sites as well as between the surveyed townships. As mentioned already, over-fertilisation is prevalent for farming in the North China Plain. On average 360 kg of nitrogen per ha are applied in wheat and 220 kg in maize, while CHEN (2003) recommends 180 kg per ha for wheat and maize. Further, fertilizer costs are the major share of variable costs at all cultivated crops. The major nitrogen fertilizers are urea and ammonium carbonate. Nearly 80 per cent of the applied nitrogen originates from these fertilizers. Manure is only applied in wheat and it plays only a minor role as nitrogen source. About one third of the farm households cultivates wheat exclusively for own consumption and these farm households apply more nitrogen in wheat cultivation than the remaining farm households. The average yield of 5.7 t per ha in wheat and of 6.4 tons in maize enables gross margins of about 4 000 ¥ (400 ?) per ha, while in cotton and cultivation of peanuts the average gross margin is twice this amount. In chapter 6 the efficiency of the agricultural system is analysed. This analysis includes an impact analysis on nitrogen input and yield as well as an economic and ecologic optimum analysis of the nitrogen input. Nitrogen application rates show a broad variation at all cultivated crops. The impact analysis on nitrogen input does not show any clear and unique influence from the income structure of the farm household. Hence, additional cash income and less available family work force for farm work have no impact on the nitrogen application level. The analysis of the fertilizer costs instead of the amount of applied nitrogen confirms this statement. The nitrogen input analysis provides the nitrogen price as major impact factor. Higher nitrogen input levels are connected with lower nitrogen prices. Differences in nitrogen price result from the composition of the applied fertilizer, which differs in the ratio between fertilizer price and nitrogen content. The yield of wheat and maize indicates a high variation within the survey sites, but especially between the surveyed townships. A multifactorial regression analysis identified the location as the only significant influencing factor on yield. From the agronomic point of view, nitrogen is a major yield factor, but the survey data do not indicate a clear impact of nitrogen input on yield. The estimated relationship between nitrogen input and wheat yield provides a constant-shaped yield function. This result allows the assumption that due to the long term high nitrogen inputs the crop demand for nitrogen is fulfilled in the short term and additional nitrogen input is without impact on the yield. The quadratic regression models of nitrogen input and yield in wheat and maize fail to provide applicable economic optima of nitrogen input. For this reason, the concept of KRAYL (1993) is considered to estimate an applicable production function for wheat and maize. This concept is based on a location independent production function, which can be transferred into a location specific production function by the consideration of a location specific optimum nitrogen input and the corresponding yield. In this case the recommendations of ZHEN et al. (2005) are considered, which recommend for wheat a nitrogen input of 220 kg per ha in order to harvest 5.3 t per ha. The economic optimum nitrogen input levels are higher than the nitrogen recommendations of ZHEN et al. (2005), but still lower than the average nitrogen application rates. Hence, the present nitrogen price does not support the implementation of the recommended nitrogen application rates. The estimation of the economic optimum nitrogen input considers a production function based on the concept of KRAYL (1993) which is enlarged by factor and product prices. These are the crop prices and the costs of the other variable inputs, which are the variable costs excluding fertilizer costs. In this way, the gross margin can be described as a function of nitrogen input including the uniform factor crop price and the constant "other fertilizer costs". The calculated maximum gross margin in wheat of 4 057 ¥ per ha is achieved at a nitrogen input of 272 kg per ha. This level of nitrogen input is lower than the present average nitrogen input, but higher than the recommendations presented by ZHEN et al. (2005). Similar to the gross margin, the nitrogen balance is described as a function of nitrogen input, which considers the nitrogen input from fertilizer and straw left on the field from the previous cultivation as nitrogen inflow and the nitrogen content of the harvested crops as nitrogen outflow. Natural inflows and outflows are not taken into account. A nitrogen input of 205 kg per ha would result in the maximum accepted nitrogen surplus of 50 kg per ha and a gross margin of 3 365 ¥ per ha. Chapter 7 focuses on the estimation of the nitrogen balance and the analysis of relevant impact factors. The estimated nitrogen balances show at all crops, but especially in wheat cultivation a high level of nitrogen surplus, which is on average 200 kg of nitrogen per ha. The corresponding figures for maize, peanuts, and cotton are less than 100 kg of nitrogen per ha. Similar to nitrogen input, the nitrogen balance is indicated by a broad variation. This variation allows a classification of farm households into three nitrogen balance types: "equalized nitrogen balance", "slight nitrogen surplus", and "heavy nitrogen surplus". The farming system of "heavy nitrogen surplus" farm households can be characterized by low yields, high nitrogen input, and low calculated gross margin. These farm households have a share of 32 per cent of all farm households and cultivate about one third of the wheat of all surveyed farms, but their cumulated nitrogen input amounts to 50 per cent. Furthermore, this group of farm households accounts for 67 per cent of the cumulated nitrogen surplus. This situation leads to the question, which factors lead to that kind of nitrogen overuse. A binary logistic regression model is used to analyse the impact of pre-selected factors on the probability of a group membership interval, in this case to the "equalized nitrogen balance" as well as the "heavy nitrogen surplus" group. The covariates "family size", "education", "farmland", and "off-farm activities" do not show any significant influence. Similar to the nitrogen input analysis, a low nitrogen price and the application of manure increases the probability of a farm households of membership of the "heavy nitrogen surplus" group. Also, a low village average wheat yield and a high village average nitrogen input in wheat increases the probability. In order to identify parallel impacts of farm household characteristics on the nitrogen balance the group of farm households of "heavy nitrogen surplus" and "equalized nitrogen balance" are clustered. The farm households of the major cluster of the "heavy nitrogen surplus" group are characterized by less farmland and low farm households income without off-farm activities. Farm households of these characteristics are found at a minor cluster of the "equalized nitrogen balance" group, as well. A low income does not automatically lead to nitrogen application rates beyond the crop demand. Indeed, the combination of low income and high nitrogen input shows a higher probability than the combination of high income and high nitrogen input. Without doubt, the assumption that a lower income leads to a lower nitrogen input must be rejected. The nitrogen price might be a clear indicator for classification of farm households, but this criterion requires the analysis of the cultivation system of the considered farm household. For this reason, easy observable dichotomous variables are pre-selected and analysed whether a certain pattern can be used as criterion for identification as a part of a target group specific instrument. This approach does not provide applicable results. Chapter 8 deals with the simulation of scenarios of the nitrogen surplus reduction and the estimated impact on the net income of farm households. In the first step, the instrument independent potential nitrogen surplus reduction is estimated. The cumulated nitrogen surplus of wheat cultivation of all surveyed farm households can be reduced by more than 60 per cent, if all farm household would follow the nitrogen input recommendations and harvest the target yield of ZHEN et al. (2005). This scenario shows no changes in net income. However, the approach that all farmers would modify their present nitrogen application level to the recommended application rates might be too ambitious. Hence, it might be more realistic to consider a theoretical shift of half of the farm households belonging to the "heavy nitrogen surplus" group to the "slight nitrogen surplus" group. The nitrogen surplus reduction in wheat would be 18 per cent. The affected group of farm households represents 17 per cent of the wheat cultivation area, but accounts initially for 32 per cent of the total nitrogen surplus in wheat. This hypothetical shift considers the modification of the share of farm households belonging to a certain nitrogen balance type. The average nitrogen surplus and gross margin in combination with the share of farm households of nitrogen balance type is taken to estimate the overall nitrogen surplus and net income from farming of the considered nitrogen balance type. A change in the share of farm households modifies the overall nitrogen surplus and net income from farming of each nitrogen balance type and these modified values are considered as the impact of the evaluated instrument, which originate that change of share. The individual gross margin multiplied by the individual cultivation area of all farm households is summed up and it is considered as net income from farming. In the following step, the impact of an instrument on the nitrogen balance and the net income is simulated. The variable nitrogen price shows a highly significant influence towards the classification of nitrogen balance type. For this reason, a modification of the nitrogen price is selected as considered instrument. A higher nitrogen price reduces the probability of "heavy nitrogen surplus" and this difference in probability can be regarded as the share of farm households, which convert form "heavy nitrogen surplus" to "slight nitrogen surplus". In addition, a theoretical shift of "slight nitrogen surplus" farm households into "equalised nitrogen balance" farm households is considered. As instruments, a percental increase of the nitrogen price by 10 per cent is simulated. An increased nitrogen price by 10 per cent results in a reduction of the total nitrogen surplus of 4.9 per cent. The estimation of the impact on the net income from farming considers the described theoretical shift of farm households to another nitrogen balance type and a multiple regression model of the gross margin. The latter model considers all farm households and indicates a negative impact of the nitrogen price on the gross margin. A combination of both models results in a marginal reduction of net income from farming by 0.6 per cent, in case of a 10 per cent nitrogen price increase. In addition, a target simulation focuses on a more noticeable nitrogen surplus reduction. The average nitrogen price increase by 159 per cent to obtain a nitrogen surplus reduction of 50 per cent, but the net income from farming shows a reduction by 15.3 per cent. Summarized, the considered instrument "nitrogen price modification" fulfils the demand partly. It allows a nitrogen surplus reduction without a strong impact on the net income, but there are two major disadvantages. Firstly, huge nitrogen price modifications are required to gain a noticeable impact on nitrogen surplus reduction. Secondly, a nitrogen price modification affects all farmers, but there is a broad variation of the nitrogen balance and a high share of farm households actually has an equalized nitrogen balance. The discussion about the reasons for nitrogen overuse in the wheat and maize farming system in the North China Plain leads to the following results. This thesis cannot provide a comprehensive answer on the question, what the core reasons for the described surplus at the nitrogen balance are. The described high variation in nitrogen input and the reported low rate of farm households, which follow the recommended nitrogen application rates, leads to the assumption that an insufficient knowledge transfer system is the key reason for the inadequate use of the traditional cultivation system in terms of fertilizer application in the North China Plain. Lack of knowledge might be an explanation that low income farm households without off-farm activities do not have less fertilizer costs, but even have a higher probability to apply above average nitrogen rates than farm households, which have additional income from off-farm activities. The discussion about applicable instruments focuses on nitrogen tax, implementation of new agricultural technologies, and improvements in education and agricultural skills. The modification of the nitrogen price by a nitrogen tax is considered as an economically applicable instrument, but there are the described disadvantages. Furthermore, an economic instrument might not be suitable, if a noticeable share of the target group seems not to consider their farm level economic optimum as criterion in their determination of the applied nitrogen. In addition, a low nitrogen price is a suitable indicator for nitrogen overuse, but not its explanation. The nitrogen price represents the composition of the used fertilizer. An unfavourable composition can be regarded as an insufficient use of the cultivation system, which results in the described nitrogen overuse. Hence, an improvement in application of the cultivation technology might be more successful than an economic instrument. The discussion about new technologies focuses on their implementation. Only a minority of farm households follows the presently recommended nitrogen application rates and at a noticeable share of farm households the traditional cultivation system is not free of cultivation mistakes, especially in terms of nitrogen application. This raises the question, how successful a new agricultural technology can be implemented. The correct application present of the cultivation system and a proper working knowledge transfer system are the preconditions for the implementation of new technologies. For this reason, improvement in education and agricultural skills are the base instruments as well as the basis for all advanced instruments, because a sustainable cultivation system requires a sustainable implementation of its correct use.
Environmental and economic assessment of the intensive wheat - maize production system in the North China Plain
(2016) Ha, Nan; Bahrs, Enno
To ensure food security for its vast population input intensification in crop production has been one of China’s major strategies in the last decades. However, the negative environmental impact of the highly intensive crop production becomes apparent. Especially the emission of greenhouse gases (GHG) constitutes a major sustainability issue of crop production in China. The winter wheat - summer maize (WW-SM) double cropping system plays a crucial role for China’s national food security. Strong research efforts mainly focusing on field experiments insufficiently consider the economic viability of the proposed improvement strategies and farmers’actual crop management. Therefore this study aims to fill this void by assessing farmers’actual crop management in the WW-SM production system, with regard to its environmental and economic performance to derive suitable improvement strategies for more sustainable crop production in the North China Plain (NCP). This cumulative PhD thesis consists of three papers published or accepted with revisions in international peer-reviewed journals. A field survey conducted in 2011 interviewing 65 WW-SM producing farm households constitutes the core data base for the thesis’analysis. The data was supplemented by expert interviews and specific secondary data. Partial life cycle analysis and economic assessment were conducted, comprising GHG emission, product carbon footprint (PCF), gross margin (GM), variable cost per unit product and life cycle costing (LCC) as key environmental and economic indicators, respectively. The first article describes the status quo of single farm environmental and economic performance of 65 WW-SM producers. The results revealed a huge heterogeneity among farms. Astonishingly no trade-off between productivity and sustainability could be identified in the region. Building on cluster analysis, with farms grouped according to their economic and environmental performance into “poor”, “fair” and “good” producers, the regional GHG mitigation potential was estimated. Under the scenario assumption that all grain in the NCP is produced under “good” production conditions, 21% and 7% of GHG could be mitigated in wheat and maize production, respectively. To be able to address the existing heterogeneity and develop strategies towards attaining GHG mitigation in practice, the second article aimed at assessing the factors determining farmers’ current environmental and economic performance. Using stepwise multiple linear regression (SMLR) it was revealed that nitrogen (N) input and electricity for irrigation were responsible for 0.787 and 0.802 of variability (adjusted R2) in the GHG emission results of the WW and SM production, respectively. Electricity for irrigation and labor were the most significant factors explaining the differences in LCC of WW and SM production, with an adjusted coefficient of determination (adjusted R2) of 0.397 and 0.29. This finding indicates that N input, electricity for irrigation and labor are key target areas for lowering GHG emissions and production costs of the WW-SM production system in the NCP. As revealed in the second article overuse of N fertilizer, which actually constitutes a major current issue in China, offers great potential for reducing GHG emissions and production costs in the WW-SM production system. Therefore in the third article three simple and easily to apply N fertilizer recommendation strategies are tested, which could be implemented on large scale through the existing agricultural advisory system of China, at comparatively low cost. Building on the household dataset, the effects of the three N strategies under constant and changing yield levels on PCF and GM were determined for every individual farm household. The N fixed rate strategy realized the highest improvement potential in PCF and GM in WW; while the N coefficient strategy performed best in SM. The analysis furthermore revealed that improved N management has a significant positive effect on PCF, but only a marginal and insignificant effect on GM. On the other side, a potential 10 % yield loss would have only a marginal effect on PCF, but a detrimental effect on farmers’income. It will be of vital importance to avoid any yield reductions and respective severe financial losses, when promoting and implementing advanced fertilization strategies. Therefore, it is furthermore recommended to increase the price of fertilizer, improve the agricultural extensions system, and recognize farmers’ fertilizer related decision-making processes as key research areas. The presented thesis gives valuable contributions to the development of environmentally and economically more sustainable crop production systems in the NCP. The thesis concludes that an adjustment in the agricultural advisory system is required, supported by more interdisciplinary research, which is able to address the inherent complexity of realizing more sustainable crop production in China.
Essays on health and nutrition in China
(2015) Nie, Peng; Sousa-Poza, Alfonso
This dissertation aims to investigate several major socio-economic determinants of health and nutrition in China. By using data from the China Health and Nutrition Survey (CHNS) spanning from 1991 to 2009, this enhances the understanding of the transition of health and nutrition with such unprecedented economic and social changes in China. This dissertation contains six chapters: more specifically, Chapter 1 gives a brief description of general background, research aim and also the outline. Then Chapter 2 examines the association between maternal employment and childhood obesity. Chapter 3 takes a comprehensive look at how income changes are related to calorie intake. Chapter 4 investigates the impacts of peers (one of most important aspects of social networks) on childhood and adolescent adiposity. Chapter 5 assesses the nexus between long work hours and health. Finally, Chapter 6 ends with some main conclusions and discussions. Chapter 2 analyses the alarming increase of overweight and obese children and considers the higher female employment participation in China. We analyze how maternal employment is correlated with childhood obesity in China. Our work makes a non-Western comparison in this field, which is useful as it is rather difficult to generalize the results (mostly significant positive association between maternal employment and childhood obesity) from related studies in the Western world. More importantly, we further explore how maternal employment is related to two key transmitters of obesity: diet and physical activities. We find no association of maternal employment and childhood adiposity. Moreover, maternal employment is also not associated with either diet or physical activity of children. However, our results are well consistent with some recent evidence in Europe (Greve, 2011; Gwozdz et al., 2013), supporting the evidence that maternal employment might not necessarily be detrimental to child adiposity. One tentative explanation is that, the major source of informal childcare in China is grandparents, who are more likely to provide childcare with a high quality. In Chapter 3, we provide an empirical analysis that looks at the association between income and calorie intake via a variety of parametric, nonparametric and semiparametric approaches. By means of panel data settings, we are capable of capturing time-invariant individual heterogeneity. It is worth noting that taking a close look at calorie-income elasticities is crucial and implicative of the effectiveness of income-mediated policies for food security in China. Our findings provide strong evidence that calorie-income elasticities are small, irrespective of using parametric, nonparametric, or semiparametric techniques. Furthermore, these elasticities remain small when taking nonlinearities into consideration, and also for sub-analysis for gender, individuals with differences in calorie intake or even impoverished households. Although calorie-income are small, our results are well in line with some prior studies (Bishop et al., 2010; Lu and Luhrmann, 2012; Shankar, 2010; Zhong et al., 2012), suggesting that households might be quite successful in maintaining calorie intake stable as income changes. Also note, despite the marked increase in income, the Chinese demand for better food quality, food diversity and food safety have amplified (Gale and Huang, 2007; Liu et al., 2013b), instead of an increased demand for calorie intakes. Chapter 4 takes a detailed look at how peer effects are associated with childhood and adolescent obesity in China. It expands the empirical work beyond the Western domain in light of different cultural backgrounds between individualistic and collective societies. Furthermore, it broadens the dominant front of adolescents and adults by analyzing children as well. Note that, understanding peer effects on childhood adiposity is of great significance primarily because, as emphasized by Dishion and Tipsord (2011), children’s consumption behaviors are influenced by their peers. More importantly, childhood adiposity could result in persistent adulthood overweight or obesity (Loh and Li, 2013). In addition, the use of self-perceived perceptions of body weight allows for an exploration of the relation between peer effects and individual perceptions of weight status, thereby providing insights into understanding pathways by which peer effects operate within a relatively broader environment. We provide further evidence that peer effects exist not only among adolescents, but also children, suggesting that the formation of health lifestyles associated with peers is important for young children. In addition, we find that the magnitudes of peer effects change greatly over the distribution of individual BMI and stronger effects are observable at the upper end than at the bottom or median. This finding implies that obese individuals are more vulnerable to peers. Furthermore, females are more susceptible compared to males, which mirrors some U.S studies among adolescents (see, for instance, Trogdon et al., 2008). More importantly, we find that community-level average peer BMI is associated with self-perceived bodyweight in adolescents, providing evidence that a higher average peer BMI is related to the probability of a self-assessed perception of overweigh, in particular, for adolescent girls. All in all, our results support the existence of peer effects on childhood and adolescent obesity, but the magnitudes fall within the broader range for the U.S. adolescent studies using similar specification to ours. Therefore, it implies that peer effects do not necessarily strengthen within a collectivistic society, like China, as in comparison to the counterparts of an individualistic society, like the U.S. In Chapter 5, we provide a comprehensive picture of how long work hours are related to health, using not only subjective but also objective measures. Also, it provides a valuable comparison with existing studies predominantly in the Western world. More importantly, it explores several potential mechanisms through which long work hours could impact upon one’s health. In particular, it investigates the relation between long work hours and specific lifestyles, such as sleep, diet (calorie and fat intakes, time spent food preparation and cooking), physical activities (sports participation and time spent on sedentary activities). Apart from a cross-sectional settings, it also adopts a panel analysis, which allows for controlling for unobserved individual heterogeneity. Because, to the best of our knowledge, the only three studies in China (Fritjers et al., 2009; Verité, 2004; Zhao, 2008) all investigate subjective measures of health via cross-sectional data. We reveal that working above 50 hours per week (31-40 hours per week as the comparison), increases the probability of suffering from high blood pressure, though the effects are relatively small. Also, self-evaluated health is poorer for individuals working long hours compared with those weekly working 31-40 hours, however the effect is not so strong. Eventually, long work hours have various impacts of different aspects of individual lifestyles. Specifically, we cannot find a positive correlation between long work hours and obesity. Nevertheless, long work hours seem to be related to a decreased fat intake and less time spent on sedentary activity like watching TV. But, long work hours decrease the probability of sports participation. In summary, we provide limited evidence that long work hours in China have deleterious influences on health or lifestyles. Therefore, further research needs to explore the potential impacts of long work hours on other health or lifestyle measures. References Bishop, J.A. Liu, H.Y. & Zheng, B.H. 2010. Rising incomes and nutritional inequality in China. . In: BISHOP, J. A. (ed.) Studies in Applied Welfare Analysis: Papers from the Third ECINEQ Meeting. Bingley: Emerald Group Publishing. Dishion, T.J. & Tipsord, J.M. 2011. Peer contagion in child and adolescent social and emotional development. Annual Review of Psychology, 62, 189-214. Fritjers, P. Johnston, D.W. & Meng, X. 2009. The mental health cost of long working hours: the case of rural Chinese migrants. Mimeo. Greve, J. 2011. New results on the effect of maternal work hours on childrens overweight status: does the quality of child care matter? Labour Economics, 18(5), 579-590. Gwozdz, W. Sousa-Poza, A. Reisch, L.A. Ahrens, W. Henauw, S.D. Eiben, G. Fernandéz-Alvira, J.M. Hadjigeorgiou, C. De Henauw, S. Kovács, E. Lauria, F. Veidebaum, T. Williams, G. & Bammann, K. 2013. Maternal employment and childhood obesity - a European perspective. Journal of Health Economics, 32(4), 728-742. Gale, F. & Huang, K.S. 2007. Demand for food quantity and quality in China, Economic Research Report. No.32. Washington D.C. : US Department of Agriculture. Lu, L. & Luhrmann, M. 2012. The impact of Chinese income growth on nutritional outcomes. Available from Liu, R.D. Pieniak, Z. & Verbeke, W. 2013b. Consumers attitude and behaviour towards safe food in China: a review. Food Control, 33(1), 93-104. Loh, C.P. & Li, Q. 2013. Peer effects in adolescent bodyweight: evidence from rural China. Social Science & Medicine, 86, 35-44. Shankar, B. 2010. Socio-economic drivers of overnutrition in China. Journal of Human Nutrition and Dietetics, 23(5), 471-479. Trogdon, J.G. Nonnemaker, J. & Pais, J. 2008. Peer effects in adolescent overweight. Journal of Health Economics, 27(5), 1388-99. Verité 2004. Excessive overtime in Chinese supplier factories: causes, impacts and recommendations for action. Verité Research Paper, Amherst, Massachusetts. Zhong, F.N. Xiang, J. & Zhu, J. 2012. Impact of demographic dynamics on food consumption: a case study of energy intake in China. China Economic Review, 23(4), 1011-1019. Zhao, Z. 2008. Health demand and health determinants in China. Journal of Chinese Economic and Business Studies, 6(1), 77-98.
Estimation of the P fertilizer demand of China using the LePA model
(2021) Yu, Wenjia; Li, Haigang; Nkebiwe, Peteh Mehdi; Li, Guohua; Müller, Torsten; Zhang, Junling; Shen, Jianbo
Modern phosphate (P) fertilizers are sourced from P rock reserves, a finite and dwindling resource. Globally, China is the largest producer and consumer of P fertilizer and will deplete its domestic reserves within 80 years. It is necessary to avoid excess P input in agriculture through estimating P demand. We used the legacy P assessment model (LePA) to estimate P demand based on soil P management at the county, regional, and country scales according to six P application rate scenarios: (1) rate in 2012 maintained; (2) current rate maintained in low-P counties and P input stopped in high-P counties until critical Olsen-P level (CP) is reached, after which rate equals P-removal; (3) rate decreased to 1–1.5 kg ha−1 year−1 in low-P counties after CP is reached and in high-P counties; (4) rate in each county decreased to 1–8 kg ha−1 year−1 after soil Olsen-P reached CP in low P counties; (5) rate in each county was kept at P-removal rate after reduction; (6) P input was kept at the rate lower than P-offtake rate after reduction. The results showed that the total P fertilizer demand of China was 750 MT P2O5, 54% of P fertilizer can be saved from 2013 to 2080 in China, and soil Olsen-P of all counties can satisfy the demand for high crop yields. The greatest potential to decrease P input was in Yangtze Plain and South China, which reached 60%. Our results provide a firm basis to analyze the depletion of P reserves in other countries.
Factors influencing the adoption of agricultural machinery by Chinese maize farmers
(2021) Quan, Xiuhao; Doluschitz, Reiner
As the major labor force has shifted from rural areas to cities, labor shortages in agricultural production have resulted. In the context of technical progress impact, and depending on farm resource endowments, farmers will choose effective labor saving technology such as machinery to substitute for the missing manual labor. The reasons behind farmers’ adoption of machinery technology are worth exploring. Therefore, this study uses 4165 Chinese maize farmers as the target group. Multivariate probit models were performed to identify the factors that affect maize farmers’ adoption of four machinery technologies as well as the interrelation between these adoption decisions. The empirical results indicate that maize sowing area, arable land area, crop diversity, family labor, subsidy, technical assistance, and economies of scale have positive effects on machinery adoption, while the number of discrete fields in the farm has a negative impact. Maize farmers in the Northeast and North have higher machinery adoption odds than other regions. The adoption of these four machinery technologies are interrelated and complementary. Finally, moderate scale production, crop diversification, subsidizing agricultural machinery and its extension education, and land consolidation, are given as recommendations for promoting the adoption of agricultural machinery by Chinese maize farmers.
Fertilizer quality and its impacts on technical efficiency and use intensity in the North China Plain
(2014) Khor, Ling Yee; Zeller, Manfred
There has been a significant increase in agricultural output in the past 50 years. A major factor of this growth is the rise in input use such as fertilizer, especially during the beginning of this period. However, the trend is not uniform throughout the world. Even though there are still regions where fertilizer can contribute greatly to the increase in yield, this input is so overused in some other places that its marginal productivity is no longer significant. In this case, not only is it a waste of valuable resources, it also leads to environmental degradation and pollution that is detrimental to human health. To make matters worse, the quality of the agricultural input itself has been of increasing concern lately. It includes problems such as normal seed being sold as hybrid seed, pesticide that is mixed with less effective chemicals, or fertilizer which contains less nutrient than that labeled on the package. We focus our research on the North China Plain, a region with both fertilizer overuse and fertilizer quality problems. The issue of low fertilizer quality is however not confined to this region only, as recent news reports have indicated that substandard or fake agricultural input is a problem in other countries as well, for example Bangladesh, Cambodia, Nigeria, Tanzania, and Vietnam. In addition, although the analysis presented in this dissertation concentrates on fertilizer, some of the methodology can also be extended to examine the impact of other agricultural inputs with questionable quality, such as seed and pesticide. The main theme of our study is split into three subtopics: efficiency, wealth effect, and use intensity, with each of them focusing on a different aspect of the impact from low quality fertilizer. The main contribution of this dissertation is that despite the widespread problem of fertilizer quality, we believe we are the first to examine its impact both theoretically and empirically on efficiency and use intensity. The theoretical contribution includes deriving the bias that exists if one were to ignore the quality aspect in the estimation of production functions and technical efficiency, especially if the research area is located at one of the places with fertilizer quality problems, such as China and the other affected countries. We also provide a theoretical framework that reconciles the different findings in the literature on the direction of wealth effect on fertilizer use. It offers a consistent explanation on why the wealth effect can be different when we are looking at regions or farmers of different wealth levels. Empirically, the dissertation quantifies the magnitude of estimation bias in input elasticity and technical efficiency in our research region of North China Plain. It also supports our theoretical derivation and shows that the direction of wealth effect is not fixed across farmers of different wealth levels. Finally, the integration of fertilizer testing into a household survey allows us to look closer at the link between perceived and true fertilizer quality, as well as how they affect the fertilizer use intensity of the farmers. The worsening fertilizer quality issue in the North China Plain is of great concern because - as this dissertation research shows - it leads to an increase in fertilizer use, which is already excessive in the area. This is not only a waste of valuable resources reducing economic efficiency but also causes environmental and health problems, e.g. through pollution of ground water. The currently implemented policy of subsidizing the fertilizer manufacturers is a double whammy in this regard because by keeping the price of the product low, it encourages the usage of an input that is already overused. It also makes the quality control of the fertilizer in the market more difficult, with the presence of so many small scale producers that are inefficient. In view of these deficiencies, it would be better to shift the policy focus from price reduction to quality improvement. A suggestion is to facilitate the award of quality labels to satisfactory products with regular third-party testing of the fertilizer to ensure that its quality does not deteriorate after receiving the label. The honest producers in the industry could also help set up a sector-wide monitoring body to prevent their image from being tarnished by the less responsible manufacturers. An additional recommendation is to increase the resources and staff available to extension service in order to increase the information flow between policymakers and farmers.
Fuel for life : domestic cooking fuels and women’s health in rural China?
(2016) Xue, Jianhong; Sousa-Poza, Alfonso; Nie, Peng
Using longitudinal and biomarker data from the China Family Panel Studies and the China Health and Nutrition Survey, this study examines the association between the type of domestic cooking fuel and the health of women aged ≥16 in rural China. Regarding three major domestic cooking fuels (wood/straw, coal and liquefied natural gas (LNG)), we find that, compared to women whose households cook with dirty fuels like wood/straw, women whose households cook with cleaner fuels like LNG have a significantly lower probability of chronic or acute diseases and are more likely to report better health. Even after controlling for unobserved individual heterogeneity, we find some evidence that women in households cooking with LNG are less likely to suffer from chronic/acute diseases. Cooking with domestic coal instead of wood or straw is also associated with elevated levels of having certain risks (such as systolic and diastolic blood pressure) related to cardiovascular diseases.
Getting people involved : a preference-based approach to water policy in China
(2009) Ahlheim, Michael
Market-oriented environmental policy instruments like taxes and fees or regulatory policy instruments like rationing are typically recommended in order to set incentives for citizens to make a sparing use of water. What is often overlooked in this context is that these instruments provoke resistance and non-compliance of citizens if they do not share the values underlying such a policy. Enforcing compliance with environmental policy instruments requires strict monitoring and the prosecution of trespassers and can be rather costly for government. The resistance to government policy and the incentives to avoid or evade the respective policy measures are the greater the less these instruments are in accordance with people's preferences, i. e. the less people accept these instruments and the goals they serve as reasonable. Compliance enforcement costs are mainly monitoring costs to identify trespassers and administration costs for their prosecution. This paper deals with possibilities to reduce such compliance costs by closing the gap between people's preferences on the one hand and government policy on the other in the case of water preservation in China.
Intensive pig production and manure management in Beijing, North China Plain
(2014) Mendoza Huaitalla, Roxana; Gallmann, Eva
China, at the forefront of the livestock revolution, has experienced a more industrialized change, with an increment of the large livestock farms and of the decoupling between the livestock and arable land. Meat production in China is dominated by pork, which comprises approximately 50% of worldwide pig production. The description of the pig husbandry and manure management systems in the large animal operations of the NCP is not widely available. In order to describe the status quo of the pig production and manurial management systems in the NCP, a large-size pig farm with a dimension of 10 ha and an annual stock of 12,000 breeding swine and 20,000 market pigs or porkers was selected. An intensive sampling plan as far as feasible of pig manure, wastewater, drinking water, and feed, the main pig farm inputs and outputs, was started in 2009. The manurial system identified in the farm was denominated as “gan qing fen” or “cleaning the manure dryly”. In this system, the pig manure (faeces with some remains of urine) was collected manually by scraping the mainly non-slatted floors of the pigsties twice a day, and the floors were then flushed with water. The results showed that the pig manure was characterized by high nutrient and heavy metal contents that might be due to the solid fraction separation from the liquid fraction under the gan qing fen manurial management system. The piggery wastewater was characterized by very low concentrations of nutrients and heavy metals as a result of their dilution with flushing water, mainly used for cleaning the pigsties. Manure and wastewater samples from weaning pigs contained the highest concentrations of nutrients and heavy metals; that could be due to the high supplementation rates of these minerals in the weaner diets. In general, it seems that the manual daily collection of pig manure in the gan qing fen system is an efficient practice in order to maintain nutrient contents in pig manure, but the use of flushing water should be reduced as it can lead to further environmental pollution. China has issued a range of environmental standards in recent years. The Chinese national standards are adoptions of international standards and are consistent across all of China. Chinese and German recommendations were compiled in order to compare them with the results obtained in this study. Based on the comparisons, it is stated that pig drinking water sourced from groundwater wells was of optimum quality as it is used for both pigs and humans. Trace minerals in pig feeds, such as lead (Pb), chromium (Cr) and cadmium (Cd), were found to be within the range of values given by the Chinese and German feeding recommendations. However, high mineral concentrations of zinc (Zn), manganese (Mn), copper (Cu), and arsenic (As), mainly found in the weaning feed samples, surpassed the given thresholds by almost ten times. Pig manure was compared with the German and Chinese standard for biowaste due to the nonexistence of a specific standard for animal manure in both countries. It was observed that maximum Cd, Cu and Zn concentration values surpassed the thresholds established in those recommendations. Similarly, trace mineral concentrations in the piggery wastewater were compared with the Chinese standard for irrigation water, however, it was not compared with any German standard due to the different nature of the effluent generated from the Chinese gan qing fen manurial management system, and it was found that Pb, Cd, Cr, Cu, and Zn did not comply with the irrigation water quotes. Furthermore, there is a need to re-evaluate the current Chinese standards and to strengthen the recommendations focused on the disposal, reuse and recycling of manure and wastewater of livestock origin in general. In order to evaluate the air pollutants produced in the pig farm, i.e. gas concentrations of carbon dioxide (CO2) and ammonia (NH3), and particulate matter, were measured making use of four different measurement devices. High dust concentrations were identified in the pig barns, especially during the feeding and manure cleaning events inside the farrowing and weaning barns with slatted floors. The highest NH3 concentration was recorded in the weaning barn during the summer season, while the highest CO2 concentration was reported in the gestation barn during the winter season. To conclude, using the example of an intensive pig farm near Beijing, it was identified that the main issues were the decoupling between the cropland and the pig farm, the existence of nutrient surpluses in the pig manure originating from the uncontrolled nutrient supply into the pig feeds, the manure mismanagement (open manure storage), a lack of infrastructure (broken curtains, windows, inoperative fans), aerial pollutants (high indoor concentrations of CO2, NH3 and PM1-10), extensive hand labour, and obsolete know-how with respect to resource conservation, among the most significant.
Internet use and subjective well-being in China
(2015) Sousa-Poza, Alfonso; Nimrod, Galit; Nie, Peng
Using data from the 2010 China Family Panel Studies, we analyze the association between Internet use and various measures of subjective well-being (SWB) in a sample of 16- to 60- year-old Chinese. Our analysis shows that although intensive Internet use is significantly associated with lower levels of SWB, we hardly observe any associations when the focus is on participation in specific online activities. Nevertheless, SWB depends on perceptions of Internet use; that is, the importance that different individuals ascribe to different purposes for using the Internet and how much they believe that their Internet use is displacing other activities. Our results suggest that, contrary to previous findings, differences in beneficial outcomes (the third level digital divide) do not necessarily arise from individuals’ actual Internet use (the second level digital divide) but rather may result from their subjective perceptions of such usage. Our findings also point to a possible cultural factor that puts Chinese Internet users at psychological risk.
Maternal employment and childhood obesity in China : evidence from the China health and nutrition survey
(2014) Nie, Peng; Sousa-Poza, Alfonso
Nonuse values of climate policy : an empirial study in Xinjiang and Beijing
(2013) Pelz, Sonna; Jing, Luo; Jiang Tong; Frör, Oliver; Ahlheim, Michael
Climate policy measures can be roughly subdivided into mitigation measures and adaptation measures. Mitigation policy aims at a reduction of greenhouse gas emissions with the overall goal of slowing down climate change and global warming. Since greenhouse gases like CO2, Methane etc. are global pollutants which have the same effect on world climate irrespective of where they are emitted mitigation policy creates benefits for people all over the world. Adaptation policy on the other hand does not seek to influence the world climate but, instead, is meant to reduce the negative consequences of climate change for a specific region. The benefits created by adaptation policy are, therefore, only of local importance while mitigation policy yields global benefits. This difference has, of course, consequences for the welfare economic appraisal of mitigation policy measures as compared to adaptation policy measures. Since the wellbeing of many more people worldwide is affected by mitigation measures than by adaptation measures the former will always appear more attractive in a cost-benefit analysis than the latter, at least from a global perspective. In this paper we want to show that adaption policy measures are often undervalued in cost-benefit analyses because only their so-called use values are considered, while the nonuse values they create are neglected. The use value of a commodity accrues from a direct utilization of that commodity. In an environmental context the use value of e.g. a beautiful landscape is felt by those people who visit this landscape. Beyond this use value the landscape might also have a value for people who never visit it but still enjoy the knowledge that in their country such a beautiful landscape exists and that endangered animals and plants are preserved there. This value that originates from the mere existence of a (market or environmental) good is often called its nonuse value because it is independent of a direct (and empirically observable) utilization of this good. If it can be shown that some adaptation policy measures in the context of climate policy create also nonuse values in addition to the use values this might lead to a new assessment of such measures and it might increase their chances of being approved in the political decision process. It is obvious that the systematic undervaluation of adaptation policy measures resulting from the neglect of the nonuse values they create might have the consequence that they are declined because they do not pass the cost-benefit test, though they create high nonuse values which are not considered in this test. Of course, the existence of nonuse values depends on the cultural background of the people affected by these measures and of the society they live in. Especially in an emerging country like China many people might still underestimate the importance of climate adaptation measures in comparison with economic policy measures triggering the economic growth of the country, especially if the adaptation measures are conducted in faraway regions of the country. In this study we test empirically the hypothesis that also in a growth-oriented economy like China non-materialistic values like the nonuse values of climate policy are perceived and respected by the population. This should especially hold for the better educated people living in big cities like Beijing. Therefore, we conduct a survey in Beijing where we ask people to assess a climate change adaptation project to be implemented in a faraway region, in this case in the Tarim basin in Xinjiang. In this survey we find that also Beijing citizens feel responsible for the environmental conditions in Xinjiang, especially under the impression of climate change. We find that they are even willing to contribute personally to financing a public project for the improvement of the living conditions in this remote (as viewed from Beijing) region. The rest of the paper is organized as follows: the next chapter focuses on the importance of nonuse values in environmental cost-benefit analyses; information concerning the impact of climate change on the Tarim area is provided in chapter three; the survey method and sampling procedure are introduced in chapter four; in chapter five results of the survey in Beijing are presented and analyzed, followed by some concluding remarks.
Obesity inequality and the changing shape of the bodyweight distribution in China
(2018) Nie, Peng; Ding, Lanlin; Sousa-Poza, Alfonso
Using data from the China Health and Nutrition Survey (CHNS), this study analyses changes in bodyweight (BMI and waist circumference) distributions between 1991 and 2011 among adults aged 20+ in China. To do so, we quantify the source and extent of temporal changes in bodyweight and then decompose the increase in obesity prevalence into two components: a rightward shift of the bodyweight distribution (mean growth) and a (re)distributional skewing. Our analysis reveals a clear rightward distributional shift combined with a leftward skewing. Although the relatively large size of this skewing in the first decade analysed reflects an increase in obesity inequality, this inequality growth subsides in the second decade. Nevertheless, over the entire 20-year period, obesity inequality increases significantly, especially among females, younger age groups, rural residents and individuals with low socioeconomic status.
Reducing irrigation water supply to accomplish the goal of designing sustainable cropping systems in the North China plain
(2007) Binder, Jochen; Claupein, Wilhelm
An International Research Training Group (IRTG) of the University of Hohenheim and the China Agricultural University, entitled ?Modeling Material Flows and Production Systems for Sustainable Resource Use in the North China Plain? was launched in 2004. The major hypothesis was ?that adjustments in cropping systems and management practices provided potential for sustainable resource protection on a high yield level?. The research program was conducted in one of the most important economic and agricultural regions in China, the North China Plain (NCP). The NCP is one of the major maize (Zea mays L.) and wheat (Triticum aestivum L.) growing areas. A literature review indicated that over the last two decades yields for wheat and maize increased by more than 20%, which had mainly been achieved by augmenting the amount of irrigation water and fertilizer. Besides the positive effects on yield an increasing amount of these input factors leads to many environmental problems. Field experiments were carried out to compare different cropping systems. Currently, the double cropping of winter wheat and summer maize is the common cultivation system in the NCP. It consists of growing two crops mostly winter wheat and summer maize in one year. The winter wheat production depends on a supplemental irrigation, because rainfall is concentrated in the summer months during the maize growing season. An alternative to the intensive double cropping system could be the single cultivation of spring maize. Relative less irrigation water is required for spring maize production, because the rainy season coincides with the main part of the maize growing season. Due to the longer growing season spring maize normally realises higher yields in comparison to summer maize. However, the total yield of a double copping system of wheat and maize is higher. The evaluated system three harvests in two years (winter wheat and summer maize in the first year followed by spring maize in the second year) forms a balance between the double cropping system and the single cropping of spring maize. Due to the fact that three crops are grown in two years total yield is higher in comparison to single cropping of spring maize (two harvests in two years) but lower in comparison to the traditional double cropping system (four harvests in two years). However the lower cropping index in contrast to the double cropping of wheat and maize results in a lower demand of the input factors irrigation water and N-fertilizer whereas in comparison to the single cropping of spring maize a higher amount of input factor is required. Besides the conduction of field experiments for the collection of empirical datasets, the CERES-Maize and CERES-Wheat models were used to quantify the effects of different irrigation management practices on crop growth, productivity and sustainability of agricultural production. Results indicated that there is a considerable potential for reducing the irrigation amount for winter wheat. However, the results also showed that a supplemental irrigation at critical growth stages seems to be essential to maintain high yields and to ensure an adequate gross margin. In a more complex approach the CERES-Maize model was used to simulate the yield of summer maize and spring maize across the NCP. The spatial and temporal climate variability was taken into account by using up to 30 years of weather data from 14 meteorological stations. The simulated results were linked to a Geographic Information System (GIS). Results indicated that the yield distinction between summer maize and spring maize was partially very low as a result of water shortage at flowering stage. A delay in sowing and the use of adapted cultivars with a later flowering date could help to increase spring maize yields. Summarizing, the results of this study indicate that water is one of the most limiting factors for crop production in the NCP. Further, the reduction of total water consumption will become more and more important with water becoming increasingly scarce and thus costly. Consequently agriculture has to undergo and is already undergoing dramatic changes. The results of this study indicated that there are several possibilities optimize cropping systems in the NCP, focussing on a more sustainable use of water while maintaining high yields. In this context, crop models are valuable tools for e.g. irrigation planning or evaluating different cropping designs in the NCP.