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We report on the effects of forest management practices of understory removal and N-fixing species (Cassia alata) addition on soil
CO2 fluxes in an Eucalyptus urophylla plantation (EUp), Acacia crassicarpa plantation (ACp), 10-species-mixed plantation (Tp), and
30-species-mixed plantation (THp) using the static chamber method in southern China. Four forest management treatments, including
(1) understory removal (UR); (2) C. alata addition (CA); (3) understory removal and replacement with C. alata (UR+CA); and (4)
control without any disturbances (CK), were applied in the above four forest plantations with three replications for each treatment.
The results showed that soil CO2 fluxes rates remained at a high level during the rainy season (from April to September), followed by
a rapid decrease after October reaching a minimum in February. Soil CO2 fluxes were significantly higher (P < 0.01) in EUp (132.6
mg/(m2·hr)) and ACp (139.8 mg/(m2·hr)) than in Tp (94.0 mg/(m2·hr)) and THp (102.9 mg/(m2·hr)). Soil CO2 fluxes in UR and CA
were significantly higher (P < 0.01) among the four treatments, with values of 105.7, 120.4, 133.6 and 112.2 mg/(m2·hr) for UR+CA,
UR, CA and CK, respectively. Soil CO2 fluxes were positively correlated with soil temperature (P < 0.01), soil moisture (P < 0.01),
NO3?-N (P < 0.05), and litterfall (P < 0.01), indicating that all these factors might be important controlling variables for soil CO2
fluxes. This study sheds some light on our understanding of soil CO2 flux dynamics in forest plantations under various management
practices. 相似文献
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2003年以来阿根廷与乌拉圭之间纸浆厂争端,是近年来国际环境法领域中跨界河流非航行使用争端的一个典型案例,其判决对国际环境法之发展及国内环境法之完善都颇具价值。 相似文献
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随着乌拉圭回合的结束及其“最后文件”协议的达成,国际贸易还将面临新的挑战。通过对乌拉圭回合及其“最后文件”与环境保护问题的简要分析,可以预示环境保护将是国际贸易所面临的新挑战之一。 相似文献
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乌拉圭和阿根廷围绕界河沿岸建立大型纸浆厂引发的争议,因涉及到世界银行、南方共同市场等国际机构,以及关系环境保护与经济发展等问题而备受关注。争议围绕乌拉圭单方面修建和运行纸浆厂是否违反了边界水利用条约而展开。国际法院分析了界水利用与环境保护、跨界环境污 相似文献
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