A households′production behavior directly influences the quality of the environment and determines the successful development of nature reserves.Meanwhile,the households′production behaviors are complicated by inter...A households′production behavior directly influences the quality of the environment and determines the successful development of nature reserves.Meanwhile,the households′production behaviors are complicated by interrelated factors,such as protection attitudes,resource endowment,and family wealth.This research evaluated households near the Crested Ibis National Nature Reserve in Shaanxi Province,acquiring data from 436 households around Yang County and Ningshan County in the south slope of Qinling Mountains,China.Based on the collected data,we developed a structural equation model to evaluate the coupling relationships among households′ protection attitudes,production behaviors,resource endowment,and family wealth.The results showed that:1) households with great resource endowment had more negative attitudes,probably due to their greater protection costs;2) the households with higher education levels had worse protection attitudes;3) the households with more family wealth were likely to use fewer fertilizers,pesticides,and firewood;4) the households with more resource endowment showed less production and management behaviors;5) the enhancement of households' attitudes improved production behaviors to protection the environment,but the effects were not statistically significant.Our results provide a basis for the government's protection policy making,exploring the effective management measures that are beneficial for both nature reserve management and community development.展开更多
Based on the data from the Cost-benefit Data of Farm Produce and the China Agricultural Yearbook, this paper aims to examine the spatial and temporal change characteristics of total grain production and its affecting ...Based on the data from the Cost-benefit Data of Farm Produce and the China Agricultural Yearbook, this paper aims to examine the spatial and temporal change characteristics of total grain production and its affecting factors. The results show that： 1） During 1980 to 2007, total grain production increased from 3.20 ~ 108 t to 5.02 x 108 t in China, with annual increasing rate of 1.68%. From the regional disparities, most of the regions present increasing trend of total grain production except for several regions with higher level of economic development; 2） Grain sown area decreased from 1.17 × 108 ha in 1980 to 1.06 x 108 ha in 2007, which has negative effect on total grain production; 3） The increase of grain yield per unit area caused by land use intensity changes contributed to the increase of total grain yield greatly. However, as the land use intensity showed that farmers pay more attention to labor-saving input but not yield-increasing input, the less enthusiasm of farmers in grain production may become an important constraint on fu- ture grain production increase in China; 4） Based on the results, this paper proposed different land management poli- cies in different regions, for example, the government should protect cultivated land, promote large scale production. As to the less developed regions, the government should pay more attention to agricultural subsidies to promote farm- ers＇ enthusiasm in grain production.展开更多
Environmental temperature is a major factor affecting animal performance in South China. With global warming, heat stress will become more and more serious. This paper reviewed the effects of heat stress on metabolism...Environmental temperature is a major factor affecting animal performance in South China. With global warming, heat stress will become more and more serious. This paper reviewed the effects of heat stress on metabolism of proteins, glucose, fat and energy in skeletal muscle and related mechanisms so as to provide theoretical guidance for alleviating heat stress and improving production performance of animal suffering from heat stress.展开更多
Glutaminase is used industrially to enhance flavor and aroma and to enrich foodstuffs nutritionally. It also has potential for pharmaceutical application as anti-leukemia agent. The bacteria of Zymomonas mobilis has b...Glutaminase is used industrially to enhance flavor and aroma and to enrich foodstuffs nutritionally. It also has potential for pharmaceutical application as anti-leukemia agent. The bacteria of Zymomonas mobilis has been studied for ethanol production, however, there is no study regarding glutaminase production. The aim of the present study was to establish the influencing factors for the growth of Z mobilis and its relationship with glutaminase production using statistical tools. Analysis of variance in blocks was carried out in a complete block design and the Tukey test demonstrated the importance of the components of the culture medium, absence of agitation and fermentation time. Minimum culture medium was used in the optimization varying the glucose concentrations （10, 30, and 50 g/L）, glutamine （0, 0.5 and 1g/L） and culture time （18, 24 and 30 hours）. Maximum production was obtained at 8.86 U/L glutaminase. Optimized conditions were used in the growth kinetics, where typical exponential growth was observed. Glutaminase production was shown to be related to biomass production.展开更多
基金Under the auspices of Forestry Industry Research Special Funds for Public Welfare Projects(No.201004008)National Natural Science Foundation of China(No.71003007)Research Program of Food and Agriculture Organization(No.CHN/2011/077/LOA)
文摘A households′production behavior directly influences the quality of the environment and determines the successful development of nature reserves.Meanwhile,the households′production behaviors are complicated by interrelated factors,such as protection attitudes,resource endowment,and family wealth.This research evaluated households near the Crested Ibis National Nature Reserve in Shaanxi Province,acquiring data from 436 households around Yang County and Ningshan County in the south slope of Qinling Mountains,China.Based on the collected data,we developed a structural equation model to evaluate the coupling relationships among households′ protection attitudes,production behaviors,resource endowment,and family wealth.The results showed that:1) households with great resource endowment had more negative attitudes,probably due to their greater protection costs;2) the households with higher education levels had worse protection attitudes;3) the households with more family wealth were likely to use fewer fertilizers,pesticides,and firewood;4) the households with more resource endowment showed less production and management behaviors;5) the enhancement of households' attitudes improved production behaviors to protection the environment,but the effects were not statistically significant.Our results provide a basis for the government's protection policy making,exploring the effective management measures that are beneficial for both nature reserve management and community development.
基金Under the auspices of National Natural Science Foundation of China (No. 40971062)China Postdoctoral ScienceFundation (No. 20100480441)
文摘Based on the data from the Cost-benefit Data of Farm Produce and the China Agricultural Yearbook, this paper aims to examine the spatial and temporal change characteristics of total grain production and its affecting factors. The results show that： 1） During 1980 to 2007, total grain production increased from 3.20 ~ 108 t to 5.02 x 108 t in China, with annual increasing rate of 1.68%. From the regional disparities, most of the regions present increasing trend of total grain production except for several regions with higher level of economic development; 2） Grain sown area decreased from 1.17 × 108 ha in 1980 to 1.06 x 108 ha in 2007, which has negative effect on total grain production; 3） The increase of grain yield per unit area caused by land use intensity changes contributed to the increase of total grain yield greatly. However, as the land use intensity showed that farmers pay more attention to labor-saving input but not yield-increasing input, the less enthusiasm of farmers in grain production may become an important constraint on fu- ture grain production increase in China; 4） Based on the results, this paper proposed different land management poli- cies in different regions, for example, the government should protect cultivated land, promote large scale production. As to the less developed regions, the government should pay more attention to agricultural subsidies to promote farm- ers＇ enthusiasm in grain production.
基金Supported by Key Project of Natural Science Foundation of Hubei Province(2013CFA100)National Natural Science Foundation of China(31472117)
文摘Environmental temperature is a major factor affecting animal performance in South China. With global warming, heat stress will become more and more serious. This paper reviewed the effects of heat stress on metabolism of proteins, glucose, fat and energy in skeletal muscle and related mechanisms so as to provide theoretical guidance for alleviating heat stress and improving production performance of animal suffering from heat stress.
文摘Glutaminase is used industrially to enhance flavor and aroma and to enrich foodstuffs nutritionally. It also has potential for pharmaceutical application as anti-leukemia agent. The bacteria of Zymomonas mobilis has been studied for ethanol production, however, there is no study regarding glutaminase production. The aim of the present study was to establish the influencing factors for the growth of Z mobilis and its relationship with glutaminase production using statistical tools. Analysis of variance in blocks was carried out in a complete block design and the Tukey test demonstrated the importance of the components of the culture medium, absence of agitation and fermentation time. Minimum culture medium was used in the optimization varying the glucose concentrations （10, 30, and 50 g/L）, glutamine （0, 0.5 and 1g/L） and culture time （18, 24 and 30 hours）. Maximum production was obtained at 8.86 U/L glutaminase. Optimized conditions were used in the growth kinetics, where typical exponential growth was observed. Glutaminase production was shown to be related to biomass production.
