Rivers are important habitats for wintering waterbirds.However,they are easily influenced by natural and human activities.An important approach for waterbirds to adapt to habitats is adjusting the activity time and en...Rivers are important habitats for wintering waterbirds.However,they are easily influenced by natural and human activities.An important approach for waterbirds to adapt to habitats is adjusting the activity time and energy expenditure allocation of diurnal behavior.The compensatory foraging hypothesis predicts that increased energy expenditure leads to longer foraging time,which in turn increases food intake and helps maintain a constant energy balance.However,it is unclear whether human-disturbed habitats result in increased energy expenditure related to safety or foraging.In this study,the scan sample method was used to observe the diurnal behavior of the wintering Spot-billed Duck(Anas poecilorhyncha) in two rivers in the Xin’an River Basin from October 2021 to March 2022.The allocation of time and energy expenditure for activity in both normal and disturbed environments was calculated.The results showed that foraging accounted for the highest percentage of time and energy expenditure.Additionally,foraging decreased in the disturbed environment than that in the normal environment.Resting behavior showed the opposite trend,while other behaviors were similar in both environments.The total diurnal energy expenditure of ducks in the disturbed environment was greater than that in the normal environment,with decreased foraging and resting time percentage and increased behaviors related to immediate safety(swimming and alert) and comfort.These results oppose the compensatory foraging hypothesis in favor of increased security.The optimal diurnal energy expenditure model included river width and water depth,which had a positive relationship;an increase in either of these two factors resulted in an increase in energy expenditure.This study provides a better understanding of energy allocation strategies underlying the superficial time allocation of wintering waterbirds according to environmental conditions.Exploring these changes can help understand the maximum fitness of wintering waterbirds in response to nature and human influences.展开更多
This paper uses the data from the post-1994 tax reform in China to investigate the vertical and spatial structures of sub-provincial fiscal expenditure decentralization(SPFED)in China.The study shows that,on the whole...This paper uses the data from the post-1994 tax reform in China to investigate the vertical and spatial structures of sub-provincial fiscal expenditure decentralization(SPFED)in China.The study shows that,on the whole,SPFED tends to be gradually biased toward the county level,but inter-provincial differences are obvious,and the provincial centralization is more obvious in less economically developed regions.In terms of expenditure items,the province level enjoys a relatively higher level of economic expenditure decentralization(EED),and the county level enjoys a higher level of social expenditure decentralization(SED).In terms of internal structure,the difference in the level of EED shared by the province,prefecture and county levels is relatively smaller and the difference in the level of SED is relatively larger.In terms of spatial structure,in less developed regions,the province level enjoys a higher EED but a lower SED;in developed regions,the prefecture and county levels enjoy a higher EED but the prefecture level enjoys a relatively lower SED.These findings can provide empirical evidence for the reform of the division of power and expenditure responsibility,as well as the governance of sub-provincial governments.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 32100400)Huangshan University Startup Project of Scientific Research (2020xkjq013)Environment Conservation Research Centre of Xin’an River Basin (kypt202002)。
文摘Rivers are important habitats for wintering waterbirds.However,they are easily influenced by natural and human activities.An important approach for waterbirds to adapt to habitats is adjusting the activity time and energy expenditure allocation of diurnal behavior.The compensatory foraging hypothesis predicts that increased energy expenditure leads to longer foraging time,which in turn increases food intake and helps maintain a constant energy balance.However,it is unclear whether human-disturbed habitats result in increased energy expenditure related to safety or foraging.In this study,the scan sample method was used to observe the diurnal behavior of the wintering Spot-billed Duck(Anas poecilorhyncha) in two rivers in the Xin’an River Basin from October 2021 to March 2022.The allocation of time and energy expenditure for activity in both normal and disturbed environments was calculated.The results showed that foraging accounted for the highest percentage of time and energy expenditure.Additionally,foraging decreased in the disturbed environment than that in the normal environment.Resting behavior showed the opposite trend,while other behaviors were similar in both environments.The total diurnal energy expenditure of ducks in the disturbed environment was greater than that in the normal environment,with decreased foraging and resting time percentage and increased behaviors related to immediate safety(swimming and alert) and comfort.These results oppose the compensatory foraging hypothesis in favor of increased security.The optimal diurnal energy expenditure model included river width and water depth,which had a positive relationship;an increase in either of these two factors resulted in an increase in energy expenditure.This study provides a better understanding of energy allocation strategies underlying the superficial time allocation of wintering waterbirds according to environmental conditions.Exploring these changes can help understand the maximum fitness of wintering waterbirds in response to nature and human influences.
文摘This paper uses the data from the post-1994 tax reform in China to investigate the vertical and spatial structures of sub-provincial fiscal expenditure decentralization(SPFED)in China.The study shows that,on the whole,SPFED tends to be gradually biased toward the county level,but inter-provincial differences are obvious,and the provincial centralization is more obvious in less economically developed regions.In terms of expenditure items,the province level enjoys a relatively higher level of economic expenditure decentralization(EED),and the county level enjoys a higher level of social expenditure decentralization(SED).In terms of internal structure,the difference in the level of EED shared by the province,prefecture and county levels is relatively smaller and the difference in the level of SED is relatively larger.In terms of spatial structure,in less developed regions,the province level enjoys a higher EED but a lower SED;in developed regions,the prefecture and county levels enjoy a higher EED but the prefecture level enjoys a relatively lower SED.These findings can provide empirical evidence for the reform of the division of power and expenditure responsibility,as well as the governance of sub-provincial governments.