Browsing by Subject "Vegetation"

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Analysis of phytosociological composition and spatial structure of the central zone of Lake Baikal Eastern coast vegetation
(2018) Brianskaia, Elena; Schmieder, Klaus
The object of this study is the terrestrial ecosystem of Lake Baikal enlisted by UNESCO as the World Heritage Site. The analysis of spatial and phytosociological structures of the vegetation can reveal important stages of its formation and future dynamics. Today, the present flora and vegetation of the complex Baikal Siberian ecosystem is reflected in studies of many Russian and international phytosociologists. However, despite the huge amount of data, the phytosociological vegetation structure and its spatial distribution of the central zone of Lake Baikal eastern coast has not been studied. By this thesis, we provide the first results about the flora, phytosociological composition of the vegetation and the soil diversity of the central zone of Lake Baikal eastern coast. Selecting the area to study, we hypothesize that this complex territory can be considered as a model biome that adjoins Lake Baikal central zone in the east. The major landscape of the studied area is composed of forests complicated by the bogged valleys of the rivers Cheremshanka, Talovka and Bezymyanka. The Katkovskaya and Chernaya Griva mountains range stretches from the northto the east. 167 relevés were performed by standard methods of the Braun-Blanquet approach. To reveal the phytosociological composition of the vegetation supervised k-means classification was performed in JUICE program. By comparing the vegetation data from the studied area (167 relevés) with data from the adjacent territories of Lake Baikal, Svyatoi Nos Peninsula and the Barguzin mountain range (589 relevés) was obtained the final prodromus of the vegetation. The soil identification was performed according to Russian soil classification. The vegetation mapping was performed in ArcGIS 10.3.1 by the supervised image classification of multispectral panchromatic imagery SPOT 6. The vegetation of the territory under study is represented by four classes. The dominant type of the vegetation is represented by forests which are classified into Vaccinio-Piceetea Br.-Bl. in Br.-Bl. et al. 1939 class. The wetland vegetation includes two classes Scheuchzerio-Caricetea nigrae (Nordh. 1936) Тх. 1937 and Oxycocco-Sphagnetea Br.-Bl et R. Tx. 1943. The vegetation of shifting sands of the coastal line is classified into Brometea korotkyi Hilbig et Korolyuk 2000 class. For all phytosociological vegetation units are identified seven soil types, such as, Lithozems, Brown soil, Soddy Brown Forest soil and Rzhavozems, Fen Peat, and Peat Gleyzem. The soil distribution demonstrates its contingence with an altitudinal gradient; however, transitioning from mountain to plain areas, a hydrological regime becomes crucial. Despite a relatively small territory under study (approx. 500 km2), the vegetation is relatively diverse. Location of the studied area within the zonal forest belt contributes to the leading position of the forest communities. The close ground water occurrence creates suitable conditions for wetland vegetation formation. Lake Baikal coastal line is considered as a refugium of the unique ancient Miocene-Pliocene xerophytic vegetation and flora. Thus, Lake Baikal water body, mountain landform and close ground water occurrence contribute to the formation of diverse vegetation communities. We suggest that the vegetation of this relatively small territory can be considered as a model within the central zone of Lake Baikal eastern coast.
Landscape ecological, phytosociological and geobotanical study of eumediterranean in west of Syria
(2008) Ghazal, Abdullah; Boecker, Reinhard
The Eu-Mediterranean vegetation in Syria is widespread over a large geographical area, occupying an altitudinal zone mainly from 300 to 900 m asl., but can be also found outside this range. The study area is located to the west of the longitude 37° E, where this vegetation dominates. A complete field surveying of the landscape for all regions in the study area was carried out. The environmental variables of the landscape (climate, soil, geology, land use, flora and vegetation) were analyzed in order to achieve landscape ecology grouping. The vegetation surveying was carried out according to the Braun-Blanquet method to classify the vegetation according to the phytosociological relationships through applying the ordination method of Factor Analyses of Correspondences (FAC). Integrating plant sociology with other environmental factors enabled compiling a hierarchical framework for landscape classification and mapping from a higher to a lower level of abstraction. Land units were named with reference to indicative phytosociological alliances. That mapping system uses the potential vegetation for studying areas from the national to the local scale of landscape. The legend of the map refers to the EUCORINE land cover project (2003). The Eu-Mediterranean vegetation is organized in three types: Humid and Sub-humid; Semi-arid; and Arid. The second type can be further divided into two sub-types: cold and non-cold. The following forest types can be recognized in the Eu-Mediterranean vegetation: 1. Evergreen oak forest: this is classified as Mediterranean maquis, and comprises the major part of the forest vegetation in Syria. The main element of this forest is Quercus calliprinos. This vegetation is classified into two main types: the inland vegetation type, and the humid and sub-humid vegetation type. 2. Semi-deciduous oak forest: it consists of Quercus aegilops vegetation and occurs in many sites in Syria. 3. Coniferous forest: dominated mainly by Pinus brutia as well as few small locations of natural forests of either Pinus halepensis or Cupressus sempervirens. The vegetation of Pinus brutia forests occupies a wide area especially in the western region. These forests are distinguished into three types: humid, sub-humid and semi-arid forests. 4. Non-forest Mediterranean vegetation. 5. Running water banks vegetation. 6. Steppe vegetation. The results of the current study show that the inland Quercus calliprinos vegetation is organized in two different associations, Quercus calliprinos-Crataegus azarolus and Pruneto (tourtuosa)-Quercetum calliprini (ass. nov.) in Jabal Al-Arab and the Anti-Lebanon, respectively. The Quercus calliprinos vegetation in the humid, sub-humid and non-cold semi-arid types is organized into four associations: Querco (infectoria)-Quercetum calliprini (ass. nov.), Styraco (officinalis)-Quercetum calliprini (ass. nov.), Querco (calliprinos)-Phillyreetum mediae and Pistacio (palaestina)-Quercetum calliprini. However, those relations were strong among the northern associations especially between the Pistacio (palaestina)-Quercetum calliprini and the Querco (infectoria)-Quercetum calliprini indicating that they are in different stages of the succession. However, if the maquis were kept extensively protected from human activities and were allowed to grow spontaneously, the composition of the maquis will change from a stand with a rich mixture of species to an almost pure stand of Quercus calliprinos. The richness of climax species in the Querco (infectoria)-Quercetum calliprini, which are used as phytosociological indicators for a climax forest, emphasizes that this association is the climax in the East-Mediterranean region. The Pinus brutia is one of the important species of the Syrian forests. Its forests belong to either of the two alliances: Ptosimopappo-Quercion (microphylla) and Gonocytiso-Pinion. The latter is more important in the study area; three new associations were identified to belong to it. These are: Pino (brutia)-Cistetum villosii, Pino (brutia)-Iridetum unguicularis and Pino (brutia)-Arbutetum andrachnii. Overall, 79 land units belonging to 55 land facets were recognized in this study. The dominant parent rock in the study area is calcareous which spread widely by limestone, marl and dolomite. The green rocks appear only in one area, the Baer-Bassit, by a special type of vegetation that belongs to Ptosimopappo-Quercion. The most important alliance in the study area is Quercion calliprini, which is presented by a maquis of Quercus calliprinos with sclerophyllous vegetation. However, Gonocytiso-Pinion represents the coniferous vegetation and spreads in different sizes of patches, but it has disappeared from of southern Coastal Mountains. Oleo-Ceratonion is exposed to a high level of disturbance leading it to exist only in small patches in the Thermo-Mediterranean. The effect of human activities causes high level of disturbance in all units, leading to the disappearance of many forest types.
Testing vegetation flammability : examining seasonal and local differences in six mediterranean tree species
(2016) Kauf, Zorica; Fangmeier, Andreas
Fire is an important factor controlling vegetation structure, with 40% of terrestrial ecosystems owing their distribution and ecological properties to the accompanying fire regime. In recent decades climate and land use change led to shifts in fire regimes rendering ecosystems more vulnerable to fire. The greatest effects of these changes are expected in the Mediterranean regions. Vegetation is the only factor affecting fire regime which can be directly managed. Promotion of less flammable species is considered to be a valid management option for reducing negative consequences of wildland fires, but reliable information on vegetation flammability and its fluctuations is still lacking. This study strived to bring new insight on the relationship between environmental conditions, fluctuations of morphological characteristics, physiological activity and measured flammability related parameters of Mediterranean tree species. Only a small part of the field study data is included in the final thesis. The field study was conducted from May to October 2010 in the Mediterranean biogeographic region of Croatia, where three sampling locations were positioned along a climate gradient. Selected species included: Aleppo pine (Pinus halepensis Mill.), Holm oak (Quercus ilex L.), olive (Olea europaea L.), carob (Ceratonia siliqua L.), pomegranate (Punica granatum L.), and strawberry tree (Arbutus unedo L.). If possible, all the species were sampled on all the locations during each sampling event. Presented results include: results of the leaf litter flammability method pretesting, regular measurements on leaf litter samples, and monthly measurements on fresh leaf samples. P. granatum samples were not included in the method pretesting, instead laurel (Laurus nobilis L.), mastic (Pistacia lentiscus L.) and Japanese mock orange (Pittosporum tobira Thunb.) were sampled in order to increase the diversity of the materials included. All measured traits of leaf litter) are reported and the relationships between them examined. For fresh leaves only ignition related traits and moisture content results are presented, the relationship between them is examined, and potential effects of the Keetch-Byram drought index on these parameters are explored. Initially, the application of already established epiradiator based methods was intended. Nevertheless, method pretesting identified several flaws of established methods. It revealed that an epiradiator is not a stabile heat source as previously thought, recognising a need for monitoring and stabilizing epiradiator temperature to ensure similar heat exposure at the beginning of each tests. Furthermore, pretesting results demonstrated that materials that rarely flame under certain testing conditions can readily flame if testing conditions are slightly altered, thus challenging the presumption that low ignition frequency always corresponds to low fire danger (flammability) – a basic presumption of the vegetation flammability tests. Results of leaf litter flammability testing showed that properties of the leaf litter particles significantly change within the fire season, and indicated that species specific weathering and decomposition could play an important role in these changes. They demonstrated that a change in a single leaf trait can have opposite effects on different flammability parameters, and that these relationships are dependent on the incoming heat flux. Results of fresh leaves testing identified phenological changes as important factor governing fluctuation of moisture content and ignition related parameters, and showed that the relationship between drought indices and moisture content is not limited to shallow rooting species. They challenged the presumption that increasing leaf thickness is related to “fire retardance” – a relationship found if samples are tested outside their natural moisture content range. Instead, this study, in which fresh leaves were tested within their natural moisture content range, implies that higher sclerophylly is related to higher ignition frequency, indicating an opposite trend and confirming the importance of moisture content as one of the most important factors governing fire behaviour of the materials. All the gathered data indicated that, O. europaea, Q. ilex and P. halepensis exhibit higher tendency to ignite than C. siliqua and P. granatum; A. unedo showed high variation in ignition related parameters. Nevertheless, ignition related parameters reveal only a part of the information on fire behaviour of the material. Overall results demonstrated that the experimental setup can have tremendous impacts on the results of flammability tests, thus data interpretation should be done with caution. Furthermore, instead of attributing single flammability scores based on all measured parameters, interpretation of test results in relation to their influence on fire behaviour is advocated.
Wood-ash fertiliser and distance from drainage ditch affect the succession and biodiversity of vascular plant species in tree plantings on marginal organic soil
(2022) Zuševica, Austra; Celma, Santa; Neimane, Santa; von Cossel, Moritz; Lazdina, Dagnija
Cutaway peatland is a marginal land, which without further management is an unfavourable environment for plant growth due to low bearing capacity, high acidity and unbalanced nutrient composition of the soil. After wood-ash application, the soil becomes enriched with P and K, creating better conditions for tree growth. In addition to being economically viable, tree plantations ensure long-term carbon storage and promote habitat restoration. In a three-year term, we studied how distance from a drainage ditch and three different doses of wood-ash—5, 10, and 15 tons per hectare—affect the diversity of vascular plants in a tree plantation on a cutaway peatland. Plant species richness, vegetation cover and composition were positively affected by the distance from the drainage ditch and application with fertiliser, but in most cases, fertiliser dose had no significant effect. Both cover and species diversity were not affected by the planted tree species. In a tree plantation, herbaceous plants provide soil fertility by decay and recycling, and reduce mineral leaching in the long term. Since vascular plants play an important role in both the development of habitats and tree growth, it is important to know how multiple factors influence the development of vegetation in tree plantations.