By the qualitative and quantitative analysis method,we analyze the driving forces of arable land resource change in Jieshou City and find that the arable land resource change in Jieshou City arises mainly from social ...By the qualitative and quantitative analysis method,we analyze the driving forces of arable land resource change in Jieshou City and find that the arable land resource change in Jieshou City arises mainly from social and economic driving forces. Based on the social and economic indicator data about arable land resource in Jieshou City,we use principal component analysis to establish evaluation index system,and analyze the driving forces of dynamic arable land resource change in Jieshou City during 2006-2015. It is concluded that Jieshou's arable land change is mainly affected by economic and social factors.展开更多
Changes in glaciers in the Chinese Tianshan Mountains have been analyzed previously. However, most previous studies focused on individual glaciers and/or decentralized glacial basins. Moreover, a majority of these stu...Changes in glaciers in the Chinese Tianshan Mountains have been analyzed previously. However, most previous studies focused on individual glaciers and/or decentralized glacial basins. Moreover, a majority of these studies were published only in Chinese, which limited their usefulness at the international level. With this in mind, the authors reviewed the previous studies to create an overview of glacial changes in the Chinese Tianshan Mountains over the last five decades and discussed the effects of glacial changes on water resources. In response to climate change, glaciers in the Tianshan Mountains are shrinking rapidly and are ca. 20% smaller on average in the past five decades. Overall, the area reduction of glacial basins in the central part of the Chinese Tianshan Mountains is larger than that in the eastern and western parts. The spatial differentiation in glacial changes are caused by both differences in regional climate and in glacial factors. The effects of glacial changes on water resources vary in different river basins due to the differences in glacier distribution, characteristics of glacial change and proportion of the glacier meltwater in river runoff.展开更多
The emissions of greenhouse gasses in Egypt are about 0.58% of the total emissions of the world in the year 2015, although Egypt is one of the countries most affected by the impacts of climate change. By assessment an...The emissions of greenhouse gasses in Egypt are about 0.58% of the total emissions of the world in the year 2015, although Egypt is one of the countries most affected by the impacts of climate change. By assessment and analysis of the expected economic impacts of climate change by the year 2030, the Egyptian cultivated area will be reduced to about 0.949 million acres, equal to about 8.22% of the Egyptian cultivated area compared with the case of no sinking part of the Delta land, thus reducing crop area in Egypt to about 1.406 million acres, approximately to about 6.25% of crop area compared with the case of no sinking part of the Delta land, in addition to surplus in the Egyptian balance water to about 2.48 billion m3. In this case value of the Egyptian agriculture production will decrease by about 6.19 billion dollars, equal to about 6.19% compared with presumably no sinking of the Delta land. In the case of sinking 15% of Delta lands, with the change of the productivity and water consumption of most crops, the result will be a reduction in the cultivated area to about 0.94 million acres. In addition to decreasing the Egyptian crop area to about 1.39 million acres, with a deficit in the Egyptian balance water to about 4.74 billion m3 compared to the case of no sinking part of the Delta land, the cultivated area will decrease to about 8.17%, and the crop area will decrease 6.18%. Also, the value of the Egyptian agriculture production will decrease by about 12.51%. While compared to sinking part of the Delta land to about 15% of the total Delta area without the other impacts of climate change, the cultivated area will increase by about 0.06%;the crop area will increase by about 0.08%;also, the value of the Egyptian agriculture production will decrease by about 5.57%.展开更多
1 Introduction Shale formations bear abundant mineral resource and*unconventional petroleum resource,and the unconventional petroleum resource that contain in the shale formation should be integrated and researched.
Background It has been long thought that nitrogen(N),phosphorus(P)concentrations and their ratios(N:P)in metabolically active or functional organs(i.e.,leaves)are less responsive to environmental changes.Little attent...Background It has been long thought that nitrogen(N),phosphorus(P)concentrations and their ratios(N:P)in metabolically active or functional organs(i.e.,leaves)are less responsive to environmental changes.Little attention,however,has been paid to the reproductive organs-seeds,while seeds may maintain their nutrients more stable for the evolutionary fitness of next generation.Methods Here,we conducted a field experiment of N,P addition and drought in an alpine meadow,aiming to compare the difference of leaf and seed nutrients and stoichiometric ratios in response to these resource treatments and their interactions.Four dominant species were selected among grass and forb functional groups,including Elymus nutans,Deschampsia caespitosa,Artemisia roxburghiana and Polygonum viviparum.Results Under natural conditions,leaf N and P concentrations were consistently lower than seed among species.However,leaf nutrients were much more sensitive than seed nutrients to N and P addition.Specifically,N or P addition accordingly increased leaf N or P concentration by 22.20-44.24%and 85.54-93.61%,while only enhanced seed N or P concentration by 5.15-17.20%and 15.17-32.72%,respectively.Leaf N or P concentration was significantly reduced by P or N addition,but seed nutrients remained unchanged.In contrast,drought did not change both organ nutrients.Similarly,nutrient addition and drought had synergistic interactions on leaf nutrients,but not on seed nutrients.Conclusions This study highlights that seed nutrient concentrations could be more stable than metabolically active leaf organ when facing multidimensional resource changes.This complements the traditional view on the‘Stable Leaf Nutrient Hypothesis’with the involvement of reproductive organs.The less responsiveness of seed nutrients suggests the adaptive strategy to ensure the success of next generations and long-term plant demographic stability.展开更多
文摘By the qualitative and quantitative analysis method,we analyze the driving forces of arable land resource change in Jieshou City and find that the arable land resource change in Jieshou City arises mainly from social and economic driving forces. Based on the social and economic indicator data about arable land resource in Jieshou City,we use principal component analysis to establish evaluation index system,and analyze the driving forces of dynamic arable land resource change in Jieshou City during 2006-2015. It is concluded that Jieshou's arable land change is mainly affected by economic and social factors.
基金funded by the Funds for Creative Research Groups of China (41121001)the National Basic Research Program (2013CBA01801)+3 种基金the National Natural Science Foundation of China (41301069, 41471058)the State Key Laboratory of Cryospheric Science foundation, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences (SKLCS-ZZ-2012-01-01)West Light Program for Talent Cultivation of the Chinese Academy of Sciencesthe Special Financial Grant from the China Postdoctoral Science Foundation ( 2014T70948)
文摘Changes in glaciers in the Chinese Tianshan Mountains have been analyzed previously. However, most previous studies focused on individual glaciers and/or decentralized glacial basins. Moreover, a majority of these studies were published only in Chinese, which limited their usefulness at the international level. With this in mind, the authors reviewed the previous studies to create an overview of glacial changes in the Chinese Tianshan Mountains over the last five decades and discussed the effects of glacial changes on water resources. In response to climate change, glaciers in the Tianshan Mountains are shrinking rapidly and are ca. 20% smaller on average in the past five decades. Overall, the area reduction of glacial basins in the central part of the Chinese Tianshan Mountains is larger than that in the eastern and western parts. The spatial differentiation in glacial changes are caused by both differences in regional climate and in glacial factors. The effects of glacial changes on water resources vary in different river basins due to the differences in glacier distribution, characteristics of glacial change and proportion of the glacier meltwater in river runoff.
文摘The emissions of greenhouse gasses in Egypt are about 0.58% of the total emissions of the world in the year 2015, although Egypt is one of the countries most affected by the impacts of climate change. By assessment and analysis of the expected economic impacts of climate change by the year 2030, the Egyptian cultivated area will be reduced to about 0.949 million acres, equal to about 8.22% of the Egyptian cultivated area compared with the case of no sinking part of the Delta land, thus reducing crop area in Egypt to about 1.406 million acres, approximately to about 6.25% of crop area compared with the case of no sinking part of the Delta land, in addition to surplus in the Egyptian balance water to about 2.48 billion m3. In this case value of the Egyptian agriculture production will decrease by about 6.19 billion dollars, equal to about 6.19% compared with presumably no sinking of the Delta land. In the case of sinking 15% of Delta lands, with the change of the productivity and water consumption of most crops, the result will be a reduction in the cultivated area to about 0.94 million acres. In addition to decreasing the Egyptian crop area to about 1.39 million acres, with a deficit in the Egyptian balance water to about 4.74 billion m3 compared to the case of no sinking part of the Delta land, the cultivated area will decrease to about 8.17%, and the crop area will decrease 6.18%. Also, the value of the Egyptian agriculture production will decrease by about 12.51%. While compared to sinking part of the Delta land to about 15% of the total Delta area without the other impacts of climate change, the cultivated area will increase by about 0.06%;the crop area will increase by about 0.08%;also, the value of the Egyptian agriculture production will decrease by about 5.57%.
基金supported by funding the National Basic Research Program of China (973 Program) and the grant number is 2014CB239000
文摘1 Introduction Shale formations bear abundant mineral resource and*unconventional petroleum resource,and the unconventional petroleum resource that contain in the shale formation should be integrated and researched.
基金The Natural Science Foundation of China(32271636)the“Kezhen-Bingwei”Young Talents(2020RC003)+1 种基金the Youth Innovation Promotion Association(Grant No.2021050)National Forestry and Grassland Administration Youth Talent Support Program.
文摘Background It has been long thought that nitrogen(N),phosphorus(P)concentrations and their ratios(N:P)in metabolically active or functional organs(i.e.,leaves)are less responsive to environmental changes.Little attention,however,has been paid to the reproductive organs-seeds,while seeds may maintain their nutrients more stable for the evolutionary fitness of next generation.Methods Here,we conducted a field experiment of N,P addition and drought in an alpine meadow,aiming to compare the difference of leaf and seed nutrients and stoichiometric ratios in response to these resource treatments and their interactions.Four dominant species were selected among grass and forb functional groups,including Elymus nutans,Deschampsia caespitosa,Artemisia roxburghiana and Polygonum viviparum.Results Under natural conditions,leaf N and P concentrations were consistently lower than seed among species.However,leaf nutrients were much more sensitive than seed nutrients to N and P addition.Specifically,N or P addition accordingly increased leaf N or P concentration by 22.20-44.24%and 85.54-93.61%,while only enhanced seed N or P concentration by 5.15-17.20%and 15.17-32.72%,respectively.Leaf N or P concentration was significantly reduced by P or N addition,but seed nutrients remained unchanged.In contrast,drought did not change both organ nutrients.Similarly,nutrient addition and drought had synergistic interactions on leaf nutrients,but not on seed nutrients.Conclusions This study highlights that seed nutrient concentrations could be more stable than metabolically active leaf organ when facing multidimensional resource changes.This complements the traditional view on the‘Stable Leaf Nutrient Hypothesis’with the involvement of reproductive organs.The less responsiveness of seed nutrients suggests the adaptive strategy to ensure the success of next generations and long-term plant demographic stability.