Using Genetic Algorithms (GAs) is a powerful tool to get solution to large scale design optimization problems. This paper used GA to solve complicated design optimization problems in two different applications. The ai...Using Genetic Algorithms (GAs) is a powerful tool to get solution to large scale design optimization problems. This paper used GA to solve complicated design optimization problems in two different applications. The aims are to implement the genetic algorithm to solve these two different (nested) problems, and to get the best or optimization solutions.展开更多
Grassland-based animal husbandry and livestock production is the main contributor to livelihood creation for herdsmen.By using the structural dynamics method,this study quantified the changes in the food supply capaci...Grassland-based animal husbandry and livestock production is the main contributor to livelihood creation for herdsmen.By using the structural dynamics method,this study quantified the changes in the food supply capacity(FSC)of alpine grassland ecosystem and sensitivity to significant variables.The findings indicated that:i)Natural factors were the dominated forces affecting FSC,and their contribution was 71.3%.Of these natural elements,the net primary productivity(NPP)and precipitation were the largest contributors,accounting for approximately 35%.The sensitivity index of the FSC to NPP and precipitation during grassland growing season were 4.1 and 1.9 respectively.On the contrary,human factors like warm shed area,density of road,capacity for access to information,contributed to 28.7%of the total FSC.ii)More intense snow disaster had a larger negative impact on FSC.Snow disaster can cause dramatic reduction in FSC,with a loss rate of 27.6%and with none intense disaster more negative impacts,iii)The continuing increase of FSC in the past 30 years from 1984 to 2014 was due to the significant increase of precipitation and NPP in the growing season of alpine grassland.Evidently,successful adaptation to climate change was critical to combat the climatic adversely impact on FSC.Typically,strengthening information dissemination,road accessibility and knowledge popularization of local residents'disaster reduction should be place high priority for improving FSC。展开更多
Plant growth and crop production depend to a large extent on soil N supplying capacity （SNSC）： The higher the SNSC, the higher the dependence of crops on soil and the lower the N fertilizer recovery. Of the SNSC, s...Plant growth and crop production depend to a large extent on soil N supplying capacity （SNSC）： The higher the SNSC, the higher the dependence of crops on soil and the lower the N fertilizer recovery. Of the SNSC, soil organic N （ON） played a key role in supplying N nutrient to crop production and still does in many subsistence and low-input farming systems. In this paper, soil ON contents, types, chemical components and its contribution to plant production are reviewed up to date in details, the characteristics of ON in dryland soils discussed together with its chemical components, and the mineralization and availability to plants of some important chemical components are emphasized at the last part for practical considerations.展开更多
文摘Using Genetic Algorithms (GAs) is a powerful tool to get solution to large scale design optimization problems. This paper used GA to solve complicated design optimization problems in two different applications. The aims are to implement the genetic algorithm to solve these two different (nested) problems, and to get the best or optimization solutions.
基金National Natural Science Foundation of China,China(41571523,41661144038)National Basic Research Program of China,China(2013CBA01808)National Key Technology R&D Program of the Ministry of Science and Technology of China,China(2014BAC05B01).
文摘Grassland-based animal husbandry and livestock production is the main contributor to livelihood creation for herdsmen.By using the structural dynamics method,this study quantified the changes in the food supply capacity(FSC)of alpine grassland ecosystem and sensitivity to significant variables.The findings indicated that:i)Natural factors were the dominated forces affecting FSC,and their contribution was 71.3%.Of these natural elements,the net primary productivity(NPP)and precipitation were the largest contributors,accounting for approximately 35%.The sensitivity index of the FSC to NPP and precipitation during grassland growing season were 4.1 and 1.9 respectively.On the contrary,human factors like warm shed area,density of road,capacity for access to information,contributed to 28.7%of the total FSC.ii)More intense snow disaster had a larger negative impact on FSC.Snow disaster can cause dramatic reduction in FSC,with a loss rate of 27.6%and with none intense disaster more negative impacts,iii)The continuing increase of FSC in the past 30 years from 1984 to 2014 was due to the significant increase of precipitation and NPP in the growing season of alpine grassland.Evidently,successful adaptation to climate change was critical to combat the climatic adversely impact on FSC.Typically,strengthening information dissemination,road accessibility and knowledge popularization of local residents'disaster reduction should be place high priority for improving FSC。
基金supported by the National Natural Science Foundation of China(30971866 and 30230230)
文摘Plant growth and crop production depend to a large extent on soil N supplying capacity （SNSC）： The higher the SNSC, the higher the dependence of crops on soil and the lower the N fertilizer recovery. Of the SNSC, soil organic N （ON） played a key role in supplying N nutrient to crop production and still does in many subsistence and low-input farming systems. In this paper, soil ON contents, types, chemical components and its contribution to plant production are reviewed up to date in details, the characteristics of ON in dryland soils discussed together with its chemical components, and the mineralization and availability to plants of some important chemical components are emphasized at the last part for practical considerations.
