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Ways of step-by-step assessments of transformation and dynamics of soils and vegetation functioning in Kazakhstan ecosystems

Ryspekov Tilepbergen, Balkozha Marzhan

Journal of Water and Land Development

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2023

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no. 57

210--219

EN

On the basis of the obtained expeditionary data, the authors performed a comprehensive analysis of the ecosystems’ modern transformation in the studied area. In the course of the analysis, the authors found that at the present stage there have been quantitative changes (depletion of natural resources) in used landscapes, along with them, there are changes in qualitative characteristics (accumulation of resources). Now, against the background of vegetation and soil degradation, ways of their restoration are observed. New combinations of degraded and self-recovering ecosystems have emerged. Based on the analysis of the current state of different ecological systems and their relationships, the authors determined the possibilities of the dynamics of their combinations functioning by stages. This will make it possible to give a more reliable forecast of the ongoing processes in the ecosystems of the Republic of Kazakhstan.

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Decomposition Processes in Coastal Wetlands : The Importance of Suaeda salsa Community for Soil Cellulose Decomposition

Ping Y., Cui L., Pan X., Li W., Li Y., Kang X., Song T., He P.

Polish Journal of Ecology

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2018

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Vol. 66, nr 3

217--226

EN

Coastal wetlands are ecologically important all over the world, and they are relatively unstable with dramatic changes in aboveground vegetation. However, it is still unclear how the aboveground vegetation changes will influence the functioning of coastal wetland ecosystems, especially the decomposition processes. Here, we carried out a cotton strip experiment to examine the effects of Suaeda salsa community on the soil properties and the associated cellulose decomposition rates in the coastal wetlands of Liao River delta (NE China). Our results showed that S. salsa community significantly affected the contents of soil C, N, P, base cations, organic matter and the soil electrical conductivity (EC), and such effects might vary among different types or densities of aboveground vegetation. The soil cellulose decomposition rate (in terms of cotton strip tensile strength loss, CTSL) was slowed down when aboveground S. salsa communities are experiencing degradation or have been totally replaced by Phragmites australis communities. Moreover, there were positive partial correlations between soil N and CTSL, and between soil EC and CTSL, but a negative partial correlation between soil C and CTSL. Our results emphasized the importance of S. salsa community in determining the soil cellulose decomposition rate in this coastal region. The results suggest that vegetation degradation in coastal wetlands might lead to various changes in soil properties and hence affect other aspects of ecosystem functioning and services, especially nutrient cycling.

3

Ramet recruitment from different bud types along a grassland degradation gradient in Inner Mongolia, China

Qian J., Busso C. A., Wang Z., Liu Z.

Polish Journal of Ecology

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2015

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Vol. 63, nr 1

38–-52

EN

Since the contribution of total belowground bud bank and different bud types to community regeneration has rarely been explored, the vegetative offspring recruited from different belowground bud types was investigated in four plant communities along a grassland degradation gradient in northeastern China (Inner Mongolia). This gradient, between 1000 and 1500 m a.s.l., has been caused by overgrazing. It is a Leymus chinensis steppe which occupies about 3.0×105 ha. Recruitment from tiller buds was dominant (>80%) in determining the total vegetative offspring density along the whole grassland degradation gradient. However, the proportional contribution of tiller-ramets to total ramet recruitment was significantly greater (P <0.05) during earlier than later stages of grassland degradation, while that of rhizome-ramets showed an opposite pattern. While the percentage contribution and density of root-derived ramets to total ramet density increased significantly (P <0.05) during the late stages of grassland degradation, those of bulb-ramets kept relatively constant along the whole grassland degradation gradient. The relative contribution of hemicryptophytes [i.e., Achnatherum sibiricum, Cleistogenes squarrosa, Festuca ovina, Koeoleria cristata, Poa annua, Stipa grandis] to total plant species richness decreased, while that of geophytes [i.e., Agropyron cristatum, Carex korshinskyi. Leymus chinensis, Allium anisopodium, A. bidentatum, A. tenuissimum, Astragalus galactites, Cymbaria dahurica, Iris tenuifolin, Potentilla acaulis, P. bifurca, Pulsatilla turczaninovii, Serratula chinensis, Thalictrum aquilegifolium] increased with the increases of grassland degradation. Our results showed that as grassland degradation increased, changes in the proportion of tiller-, rhizome- and root-derived ramets with respect to total ramet density determined in turn changes in the proportion of hemicryptophytes and geophytes in the study plant communities.

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A new model for hazard evaluation of vegetation degradation using DPSIR framework, a case study: Sadra Region, Iran

Masoudi M., Amiri E.

Polish Journal of Ecology

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2015

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Vol. 63, nr 1

1--9

EN

Vegetation degradation causes reduction in the available biomass, and decline in the vegetative cover. The Sadra watershed which covers the upper reaches of Marharlu basin, in southern Iran, has been chosen for a test hazard assessment of this type of degradation. The different kinds of data for indicators of vegetation degradation were gathered from collecting of field data like percent canopy and biomass and also records and published reports of the governmental offices of Iran. A new model has been developed for assessing the hazard of vegetation degradation using DPSIR (Driving forces, Pressures, State, Impacts and Responses) framework. The approach is based on the use of indicators, which may be direct or indirect, ecological, technical, socioeconomic or cultural causes of environmental hazard. Taking into consideration fourteen indicators of vegetation degradation the model identifies areas with different hazard class. The preparation of hazard maps based on the Geographic Information System (GIS) analysis of these indicators will be helpful for prioritizing the areas to initiate remedial measures. By fixing the thresholds of severity classes of the fourteen indicators, a hazard map for each indicator was first prepared in GIS. The hazard classes were defined on the basis of hazard scores arrived at by assigning the appropriate attributes to the indicators and the final hazard map was prepared by intersecting fourteen hazard maps in five main hazard layers including anthropogenic, natural, current state of hazard, livestock pressure and trend of degradation in the GIS. Results show among the five main hazard maps used in the model, the most main effective indicator in vegetation degradation of the study area is ‘Current State of Hazard’. Also areas under severe hazard class have been found to be widespread (58%) and areas under moderate hazard class have been found (42%) in the Sadra watershed.