An agro-forestrial intercopping field experiment on Choerospondias axillaris cropped with Arachis hypogaea was undertaken in Subtropical China,to study the effect of agro-forestrial intercopping on photosynthetically ...An agro-forestrial intercopping field experiment on Choerospondias axillaris cropped with Arachis hypogaea was undertaken in Subtropical China,to study the effect of agro-forestrial intercopping on photosynthetically active radiation(PAR) and yield of crop.The results showed that there was a significant decline in PAR and A. hypogaea yield in agro-forestrial systems.Compared to sole A. hypogaea , A. hypogaea yield in equivalent area was decreased by 35.9% and 44.6% in 5 year old and 9 year old Choerospondias axillaris agro-forestrial systems,respectively.In addition,there was a significant spatial variability of PAR and A. hypogaea yield in agro-forestrial systems,and they increased with distance from tree line.Moreover, A. hypogaea yield had a significant correlation to PAR,which indicated that competition for light is one of the key factors to decrease yield of A. hypogaea .展开更多
Solar energy is one of clean energies which has the most development and application prospect. And solar photovoltaic industry is the main force foe the development of new energy industry. This paper points out the ob...Solar energy is one of clean energies which has the most development and application prospect. And solar photovoltaic industry is the main force foe the development of new energy industry. This paper points out the obstacles which improves the international competitiveness of China＇ s photovoltaic industry based on the analysis of the three big indexes, namely the international competitiveness of photovoltaic industry IMS, TCD and RCI, and proposes the suggestion which enhances the competitive advantage of China＇ s solar photovoltaic industry.展开更多
Aims Populus deltoides and P.euramericana are widely used in China as major forestry species.At present,little is known about their responses to nitrogen(N)deficiency when grown in monocultures or mixed plantations.Th...Aims Populus deltoides and P.euramericana are widely used in China as major forestry species.At present,little is known about their responses to nitrogen(N)deficiency when grown in monocultures or mixed plantations.The aim of this investigation was to analyze the growth,and morphological and physiological responses of P.deltoides and P.euramericana to different N levels under competition conditions.Methods We employed two Populus species(P.deltoides and P.euramericana)to discover how N deficiency affects plant traits under different competition types(P.deltoides×P.deltoides,intraspecific competition;P.euramericana×P.euramericana,intraspecific competition;P.deltoides×P.euramericana,interspecific competition).Potted seedlings were exposed to two N levels(normal N,N deficiency),and nitrogen-and competition-driven differences in growth,morphology and physiology were examined.Important Findings Under normal N conditions,interspecific competition significantly decreased the total root weight,root mass fraction(RMF),root–shoot ratio(R/S)and carbon/nitrogen ratio(C/N),and increased the leaf dry weight,leaf mass fraction and total leaf area of P.euramericana compared with intraspecific competition.The same conditions significantly affected the growth and morphological variables of P.deltoides,except for the dry weight of fine roots,R/S,specific leaf area,RMF,total nitrogen content and C/N compared with intraspecific competition.In addition,chlorophyll a(Chla),total chlorophyll(Tchl),carotenoid contents(Caro)and the carbon isotope composition(δ13C)of P.deltoides were significantly lower in interspecific competition than in intraspecific competition,but no difference was detected in P.euramericana.The effects of N deficiency on P.deltoides under intraspecific competition were stronger than under interspecific competition.In contrast,the effects of N deficiency on P.euramericana between intraspecific and interspecific competition were not significantly different.These results suggest that under normal N condition,P.deltoides is expected to gain an advantage in monocultures rather than in mixtures with P.euramericana.Under N deficiency,the growth performance of P.euramericana was more stable than that of P.deltoides under both cultivation modes.展开更多
文摘An agro-forestrial intercopping field experiment on Choerospondias axillaris cropped with Arachis hypogaea was undertaken in Subtropical China,to study the effect of agro-forestrial intercopping on photosynthetically active radiation(PAR) and yield of crop.The results showed that there was a significant decline in PAR and A. hypogaea yield in agro-forestrial systems.Compared to sole A. hypogaea , A. hypogaea yield in equivalent area was decreased by 35.9% and 44.6% in 5 year old and 9 year old Choerospondias axillaris agro-forestrial systems,respectively.In addition,there was a significant spatial variability of PAR and A. hypogaea yield in agro-forestrial systems,and they increased with distance from tree line.Moreover, A. hypogaea yield had a significant correlation to PAR,which indicated that competition for light is one of the key factors to decrease yield of A. hypogaea .
文摘Solar energy is one of clean energies which has the most development and application prospect. And solar photovoltaic industry is the main force foe the development of new energy industry. This paper points out the obstacles which improves the international competitiveness of China＇ s photovoltaic industry based on the analysis of the three big indexes, namely the international competitiveness of photovoltaic industry IMS, TCD and RCI, and proposes the suggestion which enhances the competitive advantage of China＇ s solar photovoltaic industry.
基金supported by the Key laboratory project of the Ecological Security and Protection Key Laboratory of Sichuan Province(ESP201501)the Talent Program of the Hangzhou Normal University(2016QDL020).
文摘Aims Populus deltoides and P.euramericana are widely used in China as major forestry species.At present,little is known about their responses to nitrogen(N)deficiency when grown in monocultures or mixed plantations.The aim of this investigation was to analyze the growth,and morphological and physiological responses of P.deltoides and P.euramericana to different N levels under competition conditions.Methods We employed two Populus species(P.deltoides and P.euramericana)to discover how N deficiency affects plant traits under different competition types(P.deltoides×P.deltoides,intraspecific competition;P.euramericana×P.euramericana,intraspecific competition;P.deltoides×P.euramericana,interspecific competition).Potted seedlings were exposed to two N levels(normal N,N deficiency),and nitrogen-and competition-driven differences in growth,morphology and physiology were examined.Important Findings Under normal N conditions,interspecific competition significantly decreased the total root weight,root mass fraction(RMF),root–shoot ratio(R/S)and carbon/nitrogen ratio(C/N),and increased the leaf dry weight,leaf mass fraction and total leaf area of P.euramericana compared with intraspecific competition.The same conditions significantly affected the growth and morphological variables of P.deltoides,except for the dry weight of fine roots,R/S,specific leaf area,RMF,total nitrogen content and C/N compared with intraspecific competition.In addition,chlorophyll a(Chla),total chlorophyll(Tchl),carotenoid contents(Caro)and the carbon isotope composition(δ13C)of P.deltoides were significantly lower in interspecific competition than in intraspecific competition,but no difference was detected in P.euramericana.The effects of N deficiency on P.deltoides under intraspecific competition were stronger than under interspecific competition.In contrast,the effects of N deficiency on P.euramericana between intraspecific and interspecific competition were not significantly different.These results suggest that under normal N condition,P.deltoides is expected to gain an advantage in monocultures rather than in mixtures with P.euramericana.Under N deficiency,the growth performance of P.euramericana was more stable than that of P.deltoides under both cultivation modes.
