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Socio-economic drivers of deforestation in Roghani Valley,Hindu-Raj Mountains,Northern Pakistan 总被引：1，自引：1，他引：0
Deforestation and associated ecological disturbances are the issues of global concern.Researchers have investigated a number of driving forces which accelerate the rate of deforestation at local and regional levels.These include poverty,population growth,market demand and prices,political instability,agricultural expansion and changes in property right and ownership regimes.This paper seeks to explore the impacts of population growth,changing tenure system and other socioeconomic factors on the forest cover of Roghani Valley,located in Hindu Raj Mountains,Northern Pakistan.The present study is mainly based on information collected through participatory observation,selfadministered interviews and questionnaire survey.Geographical Information System（GIS） database is also used for mapping and quantification.The results reveal that in the past three to four decades the study area has been subjected to severe deforestation and about half of the forest area has been converted into barren land.Thus,the area under natural forests decreased from 2099 to 1444 hectares in four decades.This large-scale deforestation is attributed to both proximate and under lying causes particularly traditional land tenure system and demographic development.Consequently,forest resources have been degraded and a number of plant species have disappeared from the forests of the study area while several others are in the process of disappearance. 相似文献
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Water Quality of the River Yamuna in the Delhi Stretch: Key Determinants and Management Issues 总被引：1，自引：0，他引：1
The assessment of water quality of the River Yamuna in the Delhi stretch was carried out by determining changes in the concentration levels of 19 physico‐chemical parameters. It was observed that vegetation plays an important role in acting as a biological sink for mineral nutrients, thereby restoring the water quality. It is proposed that restoration of the inundation pattern of floodplains would greatly help in re‐aeration of the overlying water and re‐absorption of pollutants through mud/water exchanges. 相似文献
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Similar to other areas of Pakistan, land resources in Khyber Pakhtunkhwa （KP） is kept under various ownership regimes for socio-economic and ecological benefits. For the last three to four decades, communal lands and resources are subjected to high rate of degradation and deterioration, which is leading to multifarious socio-economical and ecological implications. This paper intends to look into factors that are responsible for the degradation of communal land and the adaptability of the management mechanisms developed by the local inhabitants to conserve these resources. Moreover, this study also explores the sustainability of these adopted strategies in present circumstances. Data regarding socio-economic parameters of the inhabitants and their interactions with communal lands were collected through questionnaire cum interview method. As long-term climatic data for the area do not exist therefore focus group discussions were conducted to document the changing trend in rainfall regimes and temperature variations for the last about four decades. Results indicate that communal lands are highly vulnerable to degradation due to biophysical and anthropogenic factors. Local inhabitants have developed suitable measures to control the situation, however, accelerated socio-economic transformations in the area have weakened the role of local institutions and that led to further degradation of these resources. Nevertheless, a number of locally formulated rules have been revived and implemented and it is hoped that these threatened resources would be conserved. 相似文献
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Conotoxins belong to the large families of disulfide-rich peptide toxins from cone snail venom, and can act on a broad spectrum of ion channels and receptors. They are classified into different subtypes based on their targets. The α-conotoxins selectively inhibit the current of the nicotinic acetylcholine receptors. Because of their unique selectivity towards distinct n ACh R subtypes, α-conotoxins become valuable tools in n ACh R study. In addition to the X-ray structures of α-conotoxins in complex with acetylcholine-binding protein, a homolog of the n ACh R ligand-binding domain, the high-resolution crystal structures of the extracellular domain of the α1 and α9 subunits are also obtained. Such structures not only revealed the details of the configuration of n ACh R, but also provided higher sequence identity templates for modeling the binding modes of α-conotoxins to n ACh R. This mini-review summarizes recent modeling studies for the determination of the binding modes of α-conotoxins to n ACh R. As there are not crystal structures of the n ACh R in complex with conotoxins, computational modeling in combination of mutagenesis data is expected to reveal the molecular recognition mechanisms that govern the interactions between α-conotoxins and n ACh R at molecular level. An accurate determination of the binding modes of α-conotoxins on ACh Rs allows rational design of α-conotoxin analogues with improved potency or selectivity to n ACh Rs. 相似文献
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Zafri Niaz Mahmud Sameen Ishrar Jahangir Anurima Tabassum Nawshin Hasan Md. Musleh Uddin 《GeoJournal》2021,86(4):1863-1879
GeoJournal - The available approaches for measuring accessibility are rigid and complex in nature, and mostly impractical for decision-makers as they require a large number of data, logistics... 相似文献
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