Regional Environmental Change - Nitrogen (N) use efficiency (NUE) is an important indicator to evaluate the performance of N use in agricultural systems. Understanding changes in NUE is crucial to... 相似文献
Environmental Science and Pollution Research - China’s agriculture is dominated by smallholder farms, which have become major sources of negative environmental impacts including... 相似文献
Tea plantations are rapidly expanding in China and other countries in the tropical and subtropical zones, driven by relatively high private economic benefit. However, the impact of tea plantations on the regional environment, including ecosystem services and disservices are unclear. In this study, we developed an assessment framework for determining the private economic benefits and environmental externalities (the algebraic sum of the regulating services and disservices) of tea plantations in China. Our results showed that tea plantations provided private economic benefits of 5,652 yuan ha?1 year?1 (7.6 yuan?=?1 USD in 2007) for tea farmers, plus positive environmental externalities of 6,054 yuan ha?1 year?1 for the society. The environmental externalities were calculated as the sum of the value of four regulating services, including carbon sequestration (392 yuan ha?1 year?1); soil retention (72 yuan ha?1 year?1); soil fertility protection (3,189 yuan ha?1 year?1) and water conservation (2,685 yuan ha?1 year?1), and three disservices, including CO2 emission (?39 yuan ha?1 year?1), N2O emission (?137 yuan ha?1 year?1) and nonpoint source pollution (?108 yuan ha?1 year?1). Before the private optimal level, the positive environmental externalities can be maintained by private economic benefits; if a social optimal level is required, subsidies from government are necessary. 相似文献
Technological innovation is one of the potential engines to mitigate environmental pollution. However, the implementation of new technologies sometimes fails owing to socioeconomic constraints from different stakeholders. Thus, it is essential to analyze constraints of environmental technologies in order to build a pathway for their implementation. In this study, taking three technologies on rural sewage treatment in Hangzhou, China as a case study, i.e., wastewater treatment plant (WTP), constructed wetland (CW), and biogas system, we analyzed how socioeconomic constraints affect the technological choices. Results showed that socioeconomic constraints play a key role through changing the relative opportunity cost of inputs from government as compared to that of residents to deliver the public good—sewage treatment—under different economic levels. Economic level determines the technological choice, and the preferred sewage treatment technologies change from biogas system to CW and further to WTP along with the increase of economic level. Mismatch of technological choice and economic level results in failures of rural sewage treatment, e.g., the CW only work well in moderately developed regions in Hangzhou. This finding expands the environmental Kuznets law by introducing the coproduction theory into analysis (i.e., inputs from both government and residents are essential for the delivery of public goods and services such as good environmental quality). A match between technology and socioeconomic conditions is essential to the environmental governance.
Ambio - Nitrogen (N) management presents a sustainability dilemma: N is strongly linked to energy and food production, but excess reactive N causes environmental pollution. The N footprint is an... 相似文献
Plastic greenhouse vegetable cultivation (PGVC) has played a vital role in increasing incomes of farmers and expanded dramatically in last several decades. However, carbon budget after conversion from conventional vegetable cultivation (CVC) to PGVC has been poorly quantified. A full carbon cycle analysis was used to estimate the net carbon flux from PGVC systems based on the combination of data from both field observations and literatures. Carbon fixation was evaluated at two pre-selected locations in China. Results suggest that: (1) the carbon sink of PGVC is 1.21 and 1.23 Mg C ha−1 yr−1 for temperate and subtropical area, respectively; (2) the conversion from CVC to PGVC could substantially enhance carbon sink potential by 8.6 times in the temperate area and by 1.3 times in the subtropical area; (3) the expansion of PGVC usage could enhance the potential carbon sink of arable land in China overall. 相似文献