Boron,one of the essential trace elements for normal growth and development of tobacco,has a great impact on the yield and quality of flue-cured tobacco. The objective of this study is to explore the best pattern and ...Boron,one of the essential trace elements for normal growth and development of tobacco,has a great impact on the yield and quality of flue-cured tobacco. The objective of this study is to explore the best pattern and level of boron fertilizer supply of red soil in the Honghe tobacco area. In this study,the randomized block design was used to study different boron fertilizer supply methods and levels. The results showed that during transplanting,it was good to apply 1. 50 kg/ha Fertibor boron with pure boron content≥15%; at the resettling stage,it was good to spray 225 kg solution composed of 75 m L/ha Compo liquid boron with pure boron content≥130 g/L mixed with water onto leaves when night fell in a sunny day. The two fertilization methods had better effect than the basal application of boron fertilizer,and the resistance to pests and diseases or economic character of tobacco plants was better than under spraying treatment.展开更多
Urban shrinkage is becoming an increasingly common phenomenon in China.The research focus has been the identification,origin,and pattern of shrinking cities.Nevertheless,attention has also been paid to the problems as...Urban shrinkage is becoming an increasingly common phenomenon in China.The research focus has been the identification,origin,and pattern of shrinking cities.Nevertheless,attention has also been paid to the problems associated with urban shrinkage.The present study examines one typical shrinking city in China,specifically the Yichun District in Yichun City.To explore the matching relationship between residential and commercial spaces,this study analyzes supply and demand data,electricity consumption data and multi-source points of interest(POI)of residents.The results showed that the occupancy rate is not reduced in the context of urban shrinkage,and that the supply level of various commercial facilities is not in decline.Apart from leisure and entertainment facilities,the supply levels of catering,shopping and supporting facilities for life were noted to have improved.In reference to urban shrinkage,the matching relationship between residential and commercial space in the 5-min,10-min,and 15-min living circles mainly shifted to a highlevel equilibrium.The matching relationships between residential space and different types of commercial spaces change in both direction and magnitude.From the perspective of supply and demand,the spatial and temporal changes in the relationship relate to multiple factors,such as the level of economic development,the buiding age pattern,public transportation accessibility,aging,and residents’willingness to move.This study provides relevant data for managing urban shrinkage.It also helps improve the relationships between residential and commercial spaces and works to optimize the layout and structure of functional urban spaces.展开更多
基金Supported by Yunnan Tobacco Company Program(2015YN192014YN25)
文摘Boron,one of the essential trace elements for normal growth and development of tobacco,has a great impact on the yield and quality of flue-cured tobacco. The objective of this study is to explore the best pattern and level of boron fertilizer supply of red soil in the Honghe tobacco area. In this study,the randomized block design was used to study different boron fertilizer supply methods and levels. The results showed that during transplanting,it was good to apply 1. 50 kg/ha Fertibor boron with pure boron content≥15%; at the resettling stage,it was good to spray 225 kg solution composed of 75 m L/ha Compo liquid boron with pure boron content≥130 g/L mixed with water onto leaves when night fell in a sunny day. The two fertilization methods had better effect than the basal application of boron fertilizer,and the resistance to pests and diseases or economic character of tobacco plants was better than under spraying treatment.
基金Under the auspices of the National Natural Science Foundation of China(No.42171191,41771172)China Postdoctoral Science Foundation(No.2018M641760)Education Department of Jilin Province(No.JJKH20201173KJ)。
文摘Urban shrinkage is becoming an increasingly common phenomenon in China.The research focus has been the identification,origin,and pattern of shrinking cities.Nevertheless,attention has also been paid to the problems associated with urban shrinkage.The present study examines one typical shrinking city in China,specifically the Yichun District in Yichun City.To explore the matching relationship between residential and commercial spaces,this study analyzes supply and demand data,electricity consumption data and multi-source points of interest(POI)of residents.The results showed that the occupancy rate is not reduced in the context of urban shrinkage,and that the supply level of various commercial facilities is not in decline.Apart from leisure and entertainment facilities,the supply levels of catering,shopping and supporting facilities for life were noted to have improved.In reference to urban shrinkage,the matching relationship between residential and commercial space in the 5-min,10-min,and 15-min living circles mainly shifted to a highlevel equilibrium.The matching relationships between residential space and different types of commercial spaces change in both direction and magnitude.From the perspective of supply and demand,the spatial and temporal changes in the relationship relate to multiple factors,such as the level of economic development,the buiding age pattern,public transportation accessibility,aging,and residents’willingness to move.This study provides relevant data for managing urban shrinkage.It also helps improve the relationships between residential and commercial spaces and works to optimize the layout and structure of functional urban spaces.
