vegetational change
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Author(s):  
M. V. Valov ◽  
A. N. Barmin ◽  
E. N. Probst ◽  
O. S. Eroshkina ◽  
A. V. Larin

Multi-method landscape-ecological researches results on stationary parts in the river Volga delta, transformed to rank of natural sanctuary in the period of 1978-2016 are presented in this work. The main landscape dynamics tendencies are discovered, natural and anthropogenous factors of soil and vegetation cover are estimated for peculiar long inundable territories: water-soluble salts cationicanionic analysis and their migration specific features and accumulation in dependence of the limited natural and anthropogenous factors changes for long inundable soil cover for forty years period; integrated effect of meteorological, hydrological, adaphic and anthropogenous factors cumulative changes on different years fluctuations and seral vegetational change for vegetation was revealed. Multi-year researches results show that the main factors, defining content and highly soluble salts radial migration in soils, also vegetation productivity and its species composition are hydrological regime (most of all – spring-summer floodings character) and territory climatic specific features. However, it is necessary to take into account local secondary effects influence, which can have an effective refracted impact on ambient background signals besides the main primary factors effect.


2020 ◽  
Vol 7 (4) ◽  
pp. 117-130
Author(s):  
MUHAMMAD AMEEN ◽  
ABDUL MAJID KHAN ◽  
MUHAMMAD TAHIR WASEEM ◽  
RANA MANZOOR AHMAD ◽  
MUHAMMAD IMRAN ◽  
...  

Gomphotheres existed in the Siwaliks from the middle Miocene (14.2Ma) to the middle Pleistocene (0.8Ma) and became extinct later on. In this paper, we tried to discuss the reasons of such extinction of gomphotheres in the lower Pleistocene time span by considering Linear Enamel Hypoplasia (LEH) among 114 isolated tooth samples to assess whether ecological changes correlate with the stress factor in gomphotheres. For this purpose, the Siwalik gomphotheres were divided into two Groups viz. early gomphotheres (middle Miocene to late Miocene) and late gomphotheres (Pliocene to middle Pleistocene). We presented the hypothesis, that as the gomphotheres are characterized by the brachydonty and relied on browsing for their feeding while inhabiting the semi forest land setting thus, expected to have higher stress in Plio-Pleistocene time span as vegetational change around ~6 Ma may have exerted stress on late gomphotheres. The results for the occurrence of frequency of LEH indicated severe ecological stress in late gomphotheres (33%). The significant differences were found (P < 0.05) among the early gomphotheres and late gomphotheres which can be correlated to the vegetational change from C3 to C4, higher aridity indices and intensified seasonality after the late Miocene vegetational shift which may have resulted in substantial faunal turnover, extinction and speciation. We assume that such palaeoecological changes forced a competition with more pronounced grazers like of family Elephantidae and Bovidae resulting in extinction of gomphotheres during the late Pleistocene in the Siwaliks of Pakistan.


Author(s):  
S.P. Mesyats ◽  
S.P. Ostapenko

Environmental issues associated with the development of mineral deposits are largely caused by the need to store mining and processing waste which becomes a source of environmental pollution. Large areas of dumped ore processing wastes determine the expediency of applying satellite data to monitor the environmental condition of the disturbed lands in order to make justified decisions on restoring the integrity of natural landscapes, which is crucial for the Arctic regions. The purpose of the research is to use the satellite data as the basis to reveal the dynamics of plant formation on the surrounding natural terrain when implementing the technology developed in the Mining Institute of the Kola Scientific Center of the Russian Academy of Sciences in accordance with the self-organizing principle of natural systems in the framework of the rock-biota system evolution. This is achieved by introducing a gramineous plant community without creating a fertile layer, which creates a biologically active environment. Analysis of the vegetation index obtained from a time series of the satellite data that characterizes the introduced vegetational change of the gramineous plant community on the bund wall slopes at the Khibiny group of apatite-containing ore deposits demonstrates the determinant influence of phytocoenotic factors on the recovery dynamics of natural ecosystems. A geobotanical study of the monitoring site has shown that in transition from the introduced gramineous to the forest stage of vegetational change, we observe a tier structure and large-scale resettlement of species from the adjacent natural areas, which is consistent with an increase in the vegetation index and allows to predict the dynamics of the natural ecosystem recovery.


Author(s):  
Kevin J. EDWARDS ◽  
K. D. BENNETT ◽  
Althea L. DAVIES

ABSTRACTPalaeoecology has been prominent in studies of environmental change during the Holocene epoch in Scotland. These studies have been dominated by palynology (pollen, spore and related bio-and litho-stratigraphic analyses) as a key approach to multi- and inter-disciplinary investigations of topics such as vegetation, climate and landscape change. This paper highlights some key dimensions of the pollen- and vegetation-based archive, with a focus upon woodland dynamics, blanket peat, human impacts, biodiversity and conservation. Following a brief discussion of chronological, climatic, faunal and landscape contexts, the migration, survival and nature of the woodland cover through time is assessed, emphasising its time-transgressiveness and altitudinal variation. While agriculture led to the demise of woodland in lowland areas of the south and east, the spread of blanket peat was especially a phenomenon of the north and west, including the Western and Northern Isles. Almost a quarter of Scotland is covered by blanket peat and the cause(s) of its spread continue(s) to evoke recourse to climatic, topographic, pedogenic, hydrological, biotic or anthropogenic influences, while we remain insufficiently knowledgeable about the timing of the formation processes. Humans have been implicated in vegetational change throughout the Holocene, with prehistoric woodland removal, woodland management, agricultural impacts arising from arable and pastoral activities, potential heathland development and afforestation. The viability of many current vegetation communities remains a concern, in that Scottish data show reductions in plant diversity over the last 400 years, which recent conservation efforts have yet to reverse. Palaeoecological evidence can be used to test whether conservation baselines and restoration targets are appropriate to longer-term ecosystem variability and can help identify when modern conditions have no past analogues.


2012 ◽  
Vol 77 (1) ◽  
pp. 159-170 ◽  
Author(s):  
Shailesh Agrawal ◽  
Prasanta Sanyal ◽  
Anindya Sarkar ◽  
Manoj Kumar Jaiswal ◽  
Koushik Dutta

Oxygen and carbon isotope ratios of soil carbonate and carbon isotope ratios of soil organic matter (SOM) separated from three cores, Kalpi, IITK and Firozpur, of the Ganga Plain, India are used to reconstruct past rainfall variations and their effect on ambient vegetation. The δ18O values of soil carbonate (δ18OSC) analyzed from the cores range from −8.2 to −4.1‰. Using these variations in δ18OSC values we are able, for the first time, to show periodic change in rainfall amount between 100 and 18 ka with three peaks of higher monsoon at about 100, 40 and 25 ka. The estimation of rainfall variations using δ18O value of rainwater-amount effect suggests maximum decrease in rainfall intensity (~ 20%) during the last glacial maximum. The δ13C values of soil carbonate (δ13CSC) and SOM (δ13CSOM) range from −6.3 to + 1.6‰ and −28.9 to −19.4‰, respectively, implying varying proportions of C3 and C4 vegetations over the Ganga Plain during the last 100 ka. The comparison between monsoonal rainfall and atmospheric CO2 with vegetation for the time period 84 to 18 ka indicate that relative abundances of C3 and C4 vegetations were mainly driven by variations in monsoonal rainfall.


2011 ◽  
Vol 26 (3) ◽  
pp. 276-285 ◽  
Author(s):  
Petra Kaltenrieder ◽  
Willy Tinner ◽  
Byoungyoon Lee ◽  
Feng Sheng Hu

2010 ◽  
Vol 8 (1) ◽  
pp. 25-30
Author(s):  
Sae Han RYOU ◽  
Ja-Young CHOI
Keyword(s):  

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