Increasing crop production is necessary to maintain food security for the growing global population.Reducing the gap between actual and potential yield is one of the important ways to increase yield per unit area.Pote...Increasing crop production is necessary to maintain food security for the growing global population.Reducing the gap between actual and potential yield is one of the important ways to increase yield per unit area.Potential yield and the yield gap of soybean were determined for Golestan Province,Iran,using Soybean Simulation Model (SSM-i Crop2) and Geographical Information System (GIS).Information from 24 weather stations and soil data of the region were used.Yield gap and production gap were calculated at county and province levels.The average actual yield of soybean in this province was2.28 t ha^(–1) while the province’s potential yield was 4.73 t ha^(–1),so the yield gap was estimated 2.44 t ha^(–1).Thus,there is a great potential for increasing soybean yield in Golestan,which is possible through improving crop management of soybean in farmers’fields.The average water productivity of soybean was estimated to be 0.81 kg m^(–3).Spatial distribution of water productivity in soybean farms showed that the highest and the lowest water productivities (0.99 and 0.44 kg m^(–3)) were in western and eastern regions of the province,respectively,in accordance to vapour pressure deficit.It was concluded that soybean production in the province could increase by 66%(from 109 970 to 182 170 tons) if 80% of the current yield gap could be removed.展开更多
This paper constructs a two-stage sequential game model to shed light on the spillover effect of inward FDI on the efficiency of domestic firms in host countries.Our model shows that,given an optimal joint-venture pol...This paper constructs a two-stage sequential game model to shed light on the spillover effect of inward FDI on the efficiency of domestic firms in host countries.Our model shows that,given an optimal joint-venture policy made by foreign firms,the impact of the spillover effect of inward FDI is contingent upon the productivity gap between the domestic firms and foreign ones.In particular,we demonstrate that the spillover effect of inward FDI varies negatively with the productivity gap between domestic lowproductivity firms and foreign firms but works in the opposite way for high-productivity firms.This suggests that once the productivity gap widens,the entry of foreign firms will increase the efficiency of high-productivity firms but reduce the efficiency of lowproductivity firms.In support of our theoretical model,we provide robust empirical results by using the dataset of annual survey of Chinese industrial enterprises.展开更多
文摘Increasing crop production is necessary to maintain food security for the growing global population.Reducing the gap between actual and potential yield is one of the important ways to increase yield per unit area.Potential yield and the yield gap of soybean were determined for Golestan Province,Iran,using Soybean Simulation Model (SSM-i Crop2) and Geographical Information System (GIS).Information from 24 weather stations and soil data of the region were used.Yield gap and production gap were calculated at county and province levels.The average actual yield of soybean in this province was2.28 t ha^(–1) while the province’s potential yield was 4.73 t ha^(–1),so the yield gap was estimated 2.44 t ha^(–1).Thus,there is a great potential for increasing soybean yield in Golestan,which is possible through improving crop management of soybean in farmers’fields.The average water productivity of soybean was estimated to be 0.81 kg m^(–3).Spatial distribution of water productivity in soybean farms showed that the highest and the lowest water productivities (0.99 and 0.44 kg m^(–3)) were in western and eastern regions of the province,respectively,in accordance to vapour pressure deficit.It was concluded that soybean production in the province could increase by 66%(from 109 970 to 182 170 tons) if 80% of the current yield gap could be removed.
文摘This paper constructs a two-stage sequential game model to shed light on the spillover effect of inward FDI on the efficiency of domestic firms in host countries.Our model shows that,given an optimal joint-venture policy made by foreign firms,the impact of the spillover effect of inward FDI is contingent upon the productivity gap between the domestic firms and foreign ones.In particular,we demonstrate that the spillover effect of inward FDI varies negatively with the productivity gap between domestic lowproductivity firms and foreign firms but works in the opposite way for high-productivity firms.This suggests that once the productivity gap widens,the entry of foreign firms will increase the efficiency of high-productivity firms but reduce the efficiency of lowproductivity firms.In support of our theoretical model,we provide robust empirical results by using the dataset of annual survey of Chinese industrial enterprises.
