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991.
Abstract

In order to study the relationship between economic globalization and industrial pollution, this paper developed the theoretical framework and used simultaneous equations. The result shows that economic globalization has influences on the industrial pollution mainly by the direct effect of scale, structure and technology as well as the indirect effect of income and policy. Considering all the factors, economic globalization, especially foreign direct investment (FDI), will reduce industrial pollution, in which technology spillover effect plays an important role.  相似文献   
992.
Affected by natural and anthropogenic disturbances such as forest fires, insect-induced mortality and harvesting, forest stand age plays an important role in determining the distribution of carbon pools and fluxes in a variety of forest ecosystems. An improved understanding of the relationship between net primary productivity (NPP) and stand age (i.e., age-related increase and decline in forest productivity) is essential for the simulation and prediction of the global carbon cycle at annual, decadal, centurial, or even longer temporal scales. In this paper, we developed functions describing the relationship between national mean NPP and stand age using stand age information derived from forest inventory data and NPP simulated by the BEPS (Boreal Ecosystem Productivity Simulator) model in 2001. Due to differences in ecobiophysical characteristics of different forest types, NPP-age equations were developed for five typical forest ecosystems in China (deciduous needleleaf forest (DNF), evergreen needleleaf forest in tropic and subtropical zones (ENF-S), deciduous broadleaf forest (DBF), evergreen broadleaf forest (EBF), and mixed broadleaf forest (MBF)). For DNF, ENF-S, EBF, and MBF, changes in NPP with age were well fitted with a common non-linear function, with R(2) values equal to 0.90, 0.75, 0.66, and 0.67, respectively. In contrast, a second order polynomial was best suitable for simulating the change of NPP for DBF, with an R(2) value of 0.79. The timing and magnitude of the maximum NPP varied with forest types. DNF, EBF, and MBF reached the peak NPP at the age of 54, 40, and 32 years, respectively, while the NPP of ENF-S maximizes at the age of 13 years. The highest NPP of DBF appeared at 122 years. NPP was generally lower in older stands with the exception of DBF, and this particular finding runs counter to the paradigm of age-related decline in forest growth. Evaluation based on measurements of NPP and stand age at the plot-level demonstrates the reliability and applicability of the fitted NPP-age relationships. These relationships were used to replace the normalized NPP-age relationship used in the original InTEC (Integrated Terrestrial Ecosystem Carbon) model, to improve the accuracy of estimated carbon balance for China's forest ecosystems. With the revised NPP-age relationship, the InTEC model simulated a larger carbon source from 1950-1980 and a larger carbon sink from 1985-2001 for China's forests than the original InTEC model did because of the modification to the age-related carbon dynamics in forests. This finding confirms the importance of considering the dynamics of NPP related to forest age in estimating regional and global terrestrial carbon budgets.  相似文献   
993.
Major Forest Types and the Evolution of Sustainable Forestry in China   总被引:1,自引:0,他引:1  
Dai L  Wang Y  Su D  Zhou L  Yu D  Lewis BJ  Qi L 《Environmental management》2011,48(6):1066-1078
In this article, we introduce China’s major forest types and discuss the historical development of forest management in China, including actions taken over the last decade toward achieving SMF. Major challenges are identified, and a strategy for SFM implementation in China is presented. China’s forests consist of a wide variety of types with distinctive distributional patterns shaped by complex topography and multiple climate regimes. How to manage this wide array of forest resources has challenged forest managers and policy-makers since the founding of the country. Excessive exploitation of China's forest resources from the 1950s to the late 1990s contributed to environmental problems and calamities, such as floods, soil erosion, and desertification. At the start of the new millennium, the Chinese government decided to shift its emphasis from timber production towards the achievement of sustainable forest management (SFM). With a series of endeavors such as the implementation of the “Six Key Forestry Projects” and the reform of forest tenure policies, and the adoption of a classification system for China's forests, a beginning has been made at reversing the trend of environmental degradation that occurred throughout the latter half of the last century. At the same time, huge challenges remain to be tackled for the development of forestry in China.  相似文献   
994.
The management of wild mushroom is interdisciplinary in nature, whereby the biophysical considerations have to be incorporated into the context of a wide range of social, economic and political concerns. However, to date, little documentation exists illustrating an interdisciplinary approach to management of wild mushrooms. Moreover, the empirical case studies necessary for developing applicable and practical methods are even more rare. This paper adopted an interdisciplinary approach combining participatory methods to improve the habitat management of Thelephora ganbajun, an endemic and one of the most economically valuable mushroom species in Southwest China. The paper documents an empirical case of how an interdisciplinary approach facilitated the development of a scientific basis for policy and management practice, and built the local capacity to create, adopt and sustain the new rules and techniques of mushroom management. With this integrative perspective, a sustainable management strategy was developed, which was found not only technically feasible for farmers, but also acceptable to the government from an ecological and policy-related perspective. More importantly, this approach has greatly contributed to raising the income of farmers. The paper highlights how the integration of biophysical and socioeconomic factors and different knowledge systems provided a holistic perspective to problem diagnosis and resolution, which helped to cope with conventional scientific dilemmas. Finally, it concludes that the success of this interdisciplinary approach is significant in the context of policy decentralization and reform for incorporating indigenous knowledge and local participation in forest management.  相似文献   
995.
H作业区经过对节能减排中问题的总结,实施了哈得四联合站放空气回收轻烃外输、哈得一联合站二段气回收、污水闭路循环回收利用、淡化水流程优化等节能减排工程,促进了节能减排,减少了碳排放,实现了清洁生产,取得了较好的经济效益和环境效益。  相似文献   
996.
以可持续发展相关理论为基础,利用系统工程的理论和方法建立了河北省县域可持续发展指标体系及其评价标准,并在全省范围应用,对全省136个县(市)可持续发展能力做出了评价。结合评价结果,阐述了河北省县域可持续发展能力的特征,提出了河北省县域可持续发展的方向和思路。  相似文献   
997.
介绍了环境空气质量、分析用水、接种液加入量、曝气方法的选择等因素对BOD5测定的影响。提出测定过程中实验室空气质量、分析用水的选择、接种液的选择和加入量以及曝气方法应注意事项,以期得到较为准确的测定结果,提高废水中BOD5测定质量。  相似文献   
998.
张伟  施周  张茜  张骅  徐舜开 《环境化学》2011,30(2):549-554
采用溶胶-凝胶法在不同条件下制备了多壁碳纳米管(MwCNTs)负载纳米TiO2的复合光催化剂(TiO2/MWCNTs).以偶氮类染料甲基橙为模拟污染物,研究不同制备工艺参数的复合光催化剂对甲基橙的光催化降解动力学的影响.对TiO2/MWCNTs的表征结果表明,纳米TiO2较好地分散在多壁碳纳米管表面;随着温度的升高,复...  相似文献   
999.
海洋溢油污染的生态与健康危害   总被引:2,自引:0,他引:2  
随着溢油事故的频繁发生,海洋溢油污染备受关注.本文在阐述国内外海洋溢油污染现状的基础上,针对溢油污染对人类健康的影响进行了初步分析,并针对海洋环境中溢油的环境行为以及对海洋生态系统、沿岸滩涂生态系统的毒性效应进行了概述.最后,对海洋溢油污染研究的发展趋势进行了展望.  相似文献   
1000.
Human activities produced great impacts on wetlands worldwide. Taking Jiangsu Province, China, as a representative wetland region subject to extensive human activities, the aim of this study is to understand the conversion trajectory and spatial differentiation in wetland change from a multi-scale perspective. Based on multi-temporal Landsat images, it was found that the natural wetlands decreased by 11.2% from 1990 to 2006 in Jiangsu Province. Transition matrices showed that the conversion of natural wetlands to human-made wetlands (mostly aquaculture ponds) was the major form of natural wetland reduction, accounting for over 60% of the reduction. Percentage reduction and area reduc tion of natural wetlands were respectively quantified within different wetland cover zones using a moving window analysis. Average percentage reduction showed a decreasing tendency with increasing wetland cover. The high-cover and mid-cover zone presented the largest area reduction at the scales of 1-2 km and 4-8 km, respectively. Local hotspots of natural wetland reduction were mapped using the equal-interval and quantile classification schemes. The hotspots were mostly concentrated in the Lixiahe marshes and the coastal wetland areas. For the area reduction hotspots, the quantile classification presented larger area and more patches than the equal-interval classification; while an opposite result was shown for the percentage reduction hotspots. With respect to the discontinuous distribution of the natural wetlands, area reduction could be more appropriate to represent reduction hotspots than percentage reduction in the study area. These findings could have useful implications to wetland conservation.  相似文献   
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