The knowledge that soil microorganisms form an important component of below ground biodiversity, providing ecosystem services, is often not incorporated in formulation of policies to conserve and manage these microorg...The knowledge that soil microorganisms form an important component of below ground biodiversity, providing ecosystem services, is often not incorporated in formulation of policies to conserve and manage these microorganisms. Using the method of cost replacement or cost savings in terms of mineral nitrogen fertilizer that would have been required to attain the same level of nitrogen fixed biologically, this study contributes to awareness on the importance of these microorganisms. Applying the knowledge gained from several on-station and on-farm trials in Africa, complemented with assumptions on FAO-sourced data from 19 African countries, this study estimated the financial value of nitrogen fixation of legume nodulating bacteria (LNB) associated with promiscuous soybean varieties. Results show that the financial value of the nitrogen-fixing attribute of soybean in Africa, especially the promiscuous varieties, annually amounts to about $ 200 million US dollars across the 19 countries. With the fertilizer price of -$ 795 tl (June 2008), this would amount to $ 375 million. The study recommends various ways of increasing the chances of smallholder farmers benefiting from the nitrogen-fixing attribute of LNB, especially since many cannot afford adequate quantities of inorganic fertilizers for increased crop productivity.展开更多
Land change science (LCS) strives to understand and model land-use change, which will further advance the understanding of multiple issues in the socio-ecological systems. Based on GIS/RS techniques, autologistic mo...Land change science (LCS) strives to understand and model land-use change, which will further advance the understanding of multiple issues in the socio-ecological systems. Based on GIS/RS techniques, autologistic model, and household survey method, this study investigated major land use changes and their causes from 1978 to 2008 in Uxin Banner (county-level), Inner Mongolia in China and then developed an understanding of the relationships between household livelihood and land-use pattern. Results showed that cultivated land increased from 1988 to 2000, and leveled offafter 2000. Built-up land increased stably for the period 1978 2008. The change of grassland and bare land differed among the three periods. From 1978 to 1988, grassland increased by 23.3%, and bare land decreased by 20.48%. From 1988 to 2000, bare land expanded by 1.7%, but grassland declined by 1.3%. From 2000 to 2008, an increase in grassland area by 1.8% was observed, but a decrease in bare land area by 9.0% was witnessed. The autologistic models performed better than logistic models as indicated by lower Akaike Information Criterion (AIC) values. Factors associated with human activities significantly correlated with the change of cultivated land, forest land, grassland, and built-up land. The produce prices and extensive cultivated land use are major issues in the farming area. This study suggests that completing land circulation systems and maintaining the stability of price are effective solutions. By contrast, reclamation and overgrazing are major concerns in the pastoral areas. Implementing environmental policies effectively, transferring population out of rural pastoral areas, and developing modem animal husbandry are effective ways to address these issues.展开更多
This paper presents cognitive awareness levels of ecosystem services and their consumption by farmers in Guyuan City, which lies in the Jinghe watershed. Household Surveys and Participatory Rural Assessment (PRA) we...This paper presents cognitive awareness levels of ecosystem services and their consumption by farmers in Guyuan City, which lies in the Jinghe watershed. Household Surveys and Participatory Rural Assessment (PRA) were used to determine differences in farmers cognitive awareness levels. The household survey results showed that farmers have a cognitive awareness of 11 ecosystem services: food supply, air purification, environmental purification, soil and water conservation, clean water supply, natural disaster minimization, increasing income, fuel wood supply, aesthetic recreation, fodder supply and sand stabilization. The job-related requirements of a farmers’ daily life, their direct consumption of ecosystem services and the importance of ecosystem services to them all influence their cognitive awareness of ecosystem services. Through group interviews the PRA method can provide the opportunity for information exchange and discussion. The process can help farmers to gain more cognitive awareness of ecosystem services. Large changes in ecosystem services have been observed in the study area. Food production and fuel wood supply have decreased markedly, yet incomes have increased. Spatial and temporal variables, changes in ecosystem services and the level of income all have an impact on farmers’ food supply and resource consumption. Overall, the total consumption of food (cereal and potato) and fuel wood declines for most farmers and consumption of vegetables, meat, coals and gas have increased.展开更多
文摘The knowledge that soil microorganisms form an important component of below ground biodiversity, providing ecosystem services, is often not incorporated in formulation of policies to conserve and manage these microorganisms. Using the method of cost replacement or cost savings in terms of mineral nitrogen fertilizer that would have been required to attain the same level of nitrogen fixed biologically, this study contributes to awareness on the importance of these microorganisms. Applying the knowledge gained from several on-station and on-farm trials in Africa, complemented with assumptions on FAO-sourced data from 19 African countries, this study estimated the financial value of nitrogen fixation of legume nodulating bacteria (LNB) associated with promiscuous soybean varieties. Results show that the financial value of the nitrogen-fixing attribute of soybean in Africa, especially the promiscuous varieties, annually amounts to about $ 200 million US dollars across the 19 countries. With the fertilizer price of -$ 795 tl (June 2008), this would amount to $ 375 million. The study recommends various ways of increasing the chances of smallholder farmers benefiting from the nitrogen-fixing attribute of LNB, especially since many cannot afford adequate quantities of inorganic fertilizers for increased crop productivity.
基金Under the auspices of National Natural Science Foundation of China(No.41371097,40871048)
文摘Land change science (LCS) strives to understand and model land-use change, which will further advance the understanding of multiple issues in the socio-ecological systems. Based on GIS/RS techniques, autologistic model, and household survey method, this study investigated major land use changes and their causes from 1978 to 2008 in Uxin Banner (county-level), Inner Mongolia in China and then developed an understanding of the relationships between household livelihood and land-use pattern. Results showed that cultivated land increased from 1988 to 2000, and leveled offafter 2000. Built-up land increased stably for the period 1978 2008. The change of grassland and bare land differed among the three periods. From 1978 to 1988, grassland increased by 23.3%, and bare land decreased by 20.48%. From 1988 to 2000, bare land expanded by 1.7%, but grassland declined by 1.3%. From 2000 to 2008, an increase in grassland area by 1.8% was observed, but a decrease in bare land area by 9.0% was witnessed. The autologistic models performed better than logistic models as indicated by lower Akaike Information Criterion (AIC) values. Factors associated with human activities significantly correlated with the change of cultivated land, forest land, grassland, and built-up land. The produce prices and extensive cultivated land use are major issues in the farming area. This study suggests that completing land circulation systems and maintaining the stability of price are effective solutions. By contrast, reclamation and overgrazing are major concerns in the pastoral areas. Implementing environmental policies effectively, transferring population out of rural pastoral areas, and developing modem animal husbandry are effective ways to address these issues.
基金National Basic Research Program of China (2009CB421106)the Knowledge Innovation Program of CAS (KZCX2-EW-306)+1 种基金Special Funds for Sino-EU Cooperation of MOST (0813)National Key Project of Science and Technical Supporting Programs of China (2008BAK50B05)
文摘This paper presents cognitive awareness levels of ecosystem services and their consumption by farmers in Guyuan City, which lies in the Jinghe watershed. Household Surveys and Participatory Rural Assessment (PRA) were used to determine differences in farmers cognitive awareness levels. The household survey results showed that farmers have a cognitive awareness of 11 ecosystem services: food supply, air purification, environmental purification, soil and water conservation, clean water supply, natural disaster minimization, increasing income, fuel wood supply, aesthetic recreation, fodder supply and sand stabilization. The job-related requirements of a farmers’ daily life, their direct consumption of ecosystem services and the importance of ecosystem services to them all influence their cognitive awareness of ecosystem services. Through group interviews the PRA method can provide the opportunity for information exchange and discussion. The process can help farmers to gain more cognitive awareness of ecosystem services. Large changes in ecosystem services have been observed in the study area. Food production and fuel wood supply have decreased markedly, yet incomes have increased. Spatial and temporal variables, changes in ecosystem services and the level of income all have an impact on farmers’ food supply and resource consumption. Overall, the total consumption of food (cereal and potato) and fuel wood declines for most farmers and consumption of vegetables, meat, coals and gas have increased.