The larger population in the middle mountain region of Nepal is dependent on spring for domestic water use.Availability and flow regularity of springs rely on groundwater recharge(GWR)potential which is attributed to ...The larger population in the middle mountain region of Nepal is dependent on spring for domestic water use.Availability and flow regularity of springs rely on groundwater recharge(GWR)potential which is attributed to various natural and human factors.The present study is an attempt to explore the GWR potential using GIS and Remote sensing(RS)method in two watersheds of the far western middle mountains of Nepal.Spatial analysis is carried out using a weighted overlay analysis of six factors namely,slope,lithology,lineament,drainage density,rainfall,and land cover/land use.The result shows that only 16 percent of the total watershed area is under a very high recharge potential zone while 31 percent area falls under very low recharge potential.It is found that the distribution of existing spring sources is random concerning GWR potential.Water stress in Rel Gad watershed is evident which accentuates the proper management of recharge areas.The study concludes that the GIS RS tool is useful in identifying recharge potential zones.It aids to better planning for increasing recharge potential.Proper management of recharge potential area and spring water sources direct the future water availability to fulfill the increasing water need of the communities.展开更多
Aims For many terrestrial plants,nitrate is the most important form of available soil nitrogen for growth.However,many plant species,which grow on acidic,ammonium-dominated soils,exhibit a con-stantly low level of nit...Aims For many terrestrial plants,nitrate is the most important form of available soil nitrogen for growth.However,many plant species,which grow on acidic,ammonium-dominated soils,exhibit a con-stantly low level of nitrate reductase activity(NRA).Little is known about NRA in high-mountain vascular plants in similar conditions.We tested the hypothesis that high-mountain vascular plants in acidic and ammonium-dominated habitats have low levels of NRA.Methods Twenty-six plant species of the families Asteraceae,Ericaceae,Poaceae,Polygonaceae,Salicaceae,Pinaceae,Ranunculaceae,Woodsiaceae,Cyperaceae,Juncaceae,Rosaceae and Urticaceae representing different growth forms were investigated in seven native and anthropogenic habitats of subalpine and alpine belts of the Karkonosze(Hercynian middle-mountains,Central Europe),with respect to leaf NRA and mineral nitrogen forms in soil.NRA was measured by an in vivo assay for the first time directly in the field using portable water bath.Important Findings An NRA study of vascular plants from high mountains is presented for the first time,and most of the studied subalpine and alpine species were subjected to field measurements for the first time ever.Differences among species,families,growth forms and habitats for NRA were found.These differences reflected mainly the taxonomical position and in part ecological preferences.PERMANOVA analysis confirmed that variance component showed that enzyme activities were mostly explained by plant species and habitat.Overall,the subalpine and alpine species from their native habitats are characterized by very low and low ability for nitrate metabolism.We also compared NRA with Ellenberg’s N val-ues for the studied plants.Using a regression equation,N values of some species were calculated for the first time and corrected for the others.展开更多
文摘The larger population in the middle mountain region of Nepal is dependent on spring for domestic water use.Availability and flow regularity of springs rely on groundwater recharge(GWR)potential which is attributed to various natural and human factors.The present study is an attempt to explore the GWR potential using GIS and Remote sensing(RS)method in two watersheds of the far western middle mountains of Nepal.Spatial analysis is carried out using a weighted overlay analysis of six factors namely,slope,lithology,lineament,drainage density,rainfall,and land cover/land use.The result shows that only 16 percent of the total watershed area is under a very high recharge potential zone while 31 percent area falls under very low recharge potential.It is found that the distribution of existing spring sources is random concerning GWR potential.Water stress in Rel Gad watershed is evident which accentuates the proper management of recharge areas.The study concludes that the GIS RS tool is useful in identifying recharge potential zones.It aids to better planning for increasing recharge potential.Proper management of recharge potential area and spring water sources direct the future water availability to fulfill the increasing water need of the communities.
文摘Aims For many terrestrial plants,nitrate is the most important form of available soil nitrogen for growth.However,many plant species,which grow on acidic,ammonium-dominated soils,exhibit a con-stantly low level of nitrate reductase activity(NRA).Little is known about NRA in high-mountain vascular plants in similar conditions.We tested the hypothesis that high-mountain vascular plants in acidic and ammonium-dominated habitats have low levels of NRA.Methods Twenty-six plant species of the families Asteraceae,Ericaceae,Poaceae,Polygonaceae,Salicaceae,Pinaceae,Ranunculaceae,Woodsiaceae,Cyperaceae,Juncaceae,Rosaceae and Urticaceae representing different growth forms were investigated in seven native and anthropogenic habitats of subalpine and alpine belts of the Karkonosze(Hercynian middle-mountains,Central Europe),with respect to leaf NRA and mineral nitrogen forms in soil.NRA was measured by an in vivo assay for the first time directly in the field using portable water bath.Important Findings An NRA study of vascular plants from high mountains is presented for the first time,and most of the studied subalpine and alpine species were subjected to field measurements for the first time ever.Differences among species,families,growth forms and habitats for NRA were found.These differences reflected mainly the taxonomical position and in part ecological preferences.PERMANOVA analysis confirmed that variance component showed that enzyme activities were mostly explained by plant species and habitat.Overall,the subalpine and alpine species from their native habitats are characterized by very low and low ability for nitrate metabolism.We also compared NRA with Ellenberg’s N val-ues for the studied plants.Using a regression equation,N values of some species were calculated for the first time and corrected for the others.
