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长江上游丘陵区社会经济实力与坡耕地治理——以四川省中江县为例

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山地学报 2004年第4期22卷 502-507页

作者：龙花楼张献忠王军罗明国土资源部土地整理中心国土整治研究室国土资源部土地整理中心国土整治研究室北京　100035 北京　100035北京大学环境学院北京　100871

以长江上游丘陵区重点水土流失区内的四川省中江县为例,借助GIS技术,分析了坡度和水土流失约束下的耕地状况,选取农民人均纯收入、人均粮食产量和人均GDP作为评价指标,以乡为评价单元,进行了坡耕地治理的社会经济实力综合评价,进而探讨... 详细信息

以长江上游丘陵区重点水土流失区内的四川省中江县为例,借助GIS技术,分析了坡度和水土流失约束下的耕地状况,选取农民人均纯收入、人均粮食产量和人均GDP作为评价指标,以乡为评价单元,进行了坡耕地治理的社会经济实力综合评价,进而探讨了坡耕地治理的相关措施。分值在80～100间的乡镇应以大规模的改造坡耕地(坡改梯)、建设基本农田为突破口,为解决粮食问题和实现陡坡地退耕创造条件,退耕还林还草应将经济效益、生态效益和社会效益融于一体。分值在65～80间的乡镇应结合坡耕地综合治理和基本农田建设,发展生态农业,逐步实施退耕还林。分值在0～65间的乡镇应注重陡坡耕地水土流失的防治和土地利用技术的应用,不宜近期退耕。此外,通过加强农村居民点整理增加耕地,可在一定程度上解决陡坡退耕带来的粮食问题,为退耕还林还草、防治水土流失工作的顺利开展提供保障。

关键词：长江上游丘陵区水土流失坡耕地 GIS

Soluble protein and acid phosphatase exuded by ectomycorrhizal fungi and seedlings in response to excessive Cu and Cd

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Journal of environmental sciences 2009年第12期21卷 1667-1672页

作者： ZHENG Weishuang, FEI Yingheng, HUANG Yi college of environmental sciences and Engineering, peking university, {{2., china. college of environmental sciences and Engineering Peking University Beijing 100871 China

Fungi and their symbionts can alleviate heavy metal stress by exuding soluble proteins and enzymes. This study examined the role of soluble protein and acid phosphatase （APase） exuded by Xerocomus chrysenteron, an ectomycorrhizal fungus, and the seedlings of its symbiont, Chinese pine （Pinus tabulaeformis）, under conditions of excessive Cu and Cd. The growth type showed that this poorly studied ectomycorrhizal fungus was capable of tolerating high concentrations of Cu, and may be useful in phytoremediation. X. chrysenteron grew well at 80 mg/L Cu, and the EC50 for Cd was 17.82.mg/L. X. chrysenteron also showed enhanced exudation of soluble protein in both isolated and inoculated cultivations under the influence of Cu and Cd. Soluble protein exudation, however, differed under Cu and Cd stress in isolates. In mediums containing Cu, soluble protein exudation increased with concentration, but in mediums containing Cd the content of soluble protein increased to a comparable level at all concentrations. This study demonstrated that soluble protein was related to heavy metal tolerance, although the different ions played different roles. While APase activity in exudates of fungi and seedlings decreased under Cu and Cd stress in comparison to the control, the APase activity in seedlings was maintained by inoculation. Thus, X. chrysenteron facilitated the ability of plant to maintain a normal nutrient uptake, and therefore to protect it from heavy metal toxicity.

关键词： soluble protein acid phosphatase exudate Cu, Cd Xerocomus chrysenteron

Milestone of the meridian science──970th anniversary of the Chinese Bronze Statue of Meridian

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Chinese Science Bulletin 1998年第5期43卷 353-362页

作者： ZHANG Renji college of Life sciences, {{2., beijing 100871, china college of Life sciences Peking University Beijing 100871 China

For more than a thousand years, Chinese people were aware of the transmitted sensations by the application of needles on the body surface. This practice is called acupuncture. Acupuncture had been recorded and transcribed in writings and in drawings, until finally the acupoints were inscribed onto a bronze statue. The bronze statue was called the Meridian Figure. Deeply embodied in the bronze statue is a tripartite confrontation-prism representation of the humans body. This concept was a great scientific achievement in ancient china. The author traces the history of Meridian science described in traditional Chinese medical terms. Then he explores a clear analogy of the meridian pathway (MP) phenomenon. In a model system, by using a simple segmental in vertebrate, certain parallels can be demonstrated with the meridian concept. For example, the author demonstrated a clear correlation rule among the central mechano-sensory channels, and characteristics of positional discrimination in individual nerve cells from different receptive field inputs. The evidence suggests that the MP phenomenon is an objective neurobiological response. To clarify the research objective in this paper, the author suggests that the MP is a bi-directional pathway along which a positional message signal is transmitted. This phenomenon is evoked by physical stimulation, transmitted linearly across the human body segments, and is perceived by the brain. The MP consists of low resistance paths, is connected by the liquid media contained in the apposite membranous structure. At the cellular level, the regulation functions of MP must pass through along this low resistance path. Two aspects of the modern Meridian research are the functional regulation and the mechanism of intercellular liquid modulation at the nanometer level.

关键词： meridian pathway tripartite confrontation-prism coordinate position discriminative recognition apposite membranous structure.

Adjoint method for the optimum planning of industrial pollutant sources

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Science china Earth sciences 2005年第8期48卷 1270-1279页

作者： LIU Feng1,2. HU Fei2.& ZHU Jiang2.1. college of environmental sciences, peking university, {2., china 2. LAPC, Institute of Atmospheric Physics, Chinese Academy of sciences, beijing 10002., china college of environmental sciences Peking University Beijing China LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is in-troduced to deal with the environmental inequality constraints, and Lagrange function is con-structed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the infor-mation from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experi-ments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

关键词： optimum planning, industrial pollutant sources, adjoint equation, penalty function, gradient.

china's energy, environment and policy perspective

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Journal of environmental sciences 2000年第3期12卷 270-274页

作者： ZHANG Shi\|qiu (Center for environmental sciences, {{2., beijing 100871, china) Center for environmental sciences Peking University Beijing 100871 China

This paper discusses the specific features of the energy in china, and addresses those key challenges in china is that the co\|exist of (1) higher total energy production and lower per capita level; ({2. lower per capita energy resources level with unrational energy consumption structure; (3) lower energy utilization efficiency and higher energy conservation potential; and (4) unequal distribution of energy resources. It reviews the key {{2. problems related to the feature of energy production and consumption. Based on the analysis, the author furthers addresses the policy and actions needed.

关键词： energy energy production energy consumption environment policy

Biotic communities of the marine ecosystem in Meizhou Bay

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Journal of environmental sciences 1996年第1期8卷 48-56页

作者： Ren Jiuchang Cai Xiaoming (Center of environmental sciences,{{2., beijing 100871,china)Chen Bin(college of Life sciences, {{2., beijing 100871, china )Li Peng(college of Chemistry and Molecular Engineering, {{2., Bei Ctr of Envmtl Sci Peking Univ Beijing China China

The current situation of biotic communities in Meizhou Bay is presented in this *** species composition,seasonal variation,and distribution of phytoplankton,zooplankton, red tide organisms,fishes,and benthos in Meizhou Bay were investigated,and the content of chlorophyll a and primary production and their seasonal variation were also *** water quality of Meizhou Bay was monitored by measuring the density of Escherichia coli. Results reveal that there is a great variety of species in Meizhou Bay and the water in Meizhou Bay is *** the individual numbers of various organisms are very low, especially those of ***,there are more than 40 species of red tide organisms and there exist opportunities of red tides between May and *** these demand cautious be taken in the future development of this area although it has great environment capacity.

关键词： biotic community marine ecosystem Meizhou Bay.

Study on urban water environmental support capacity

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Journal of environmental sciences 1995年第4期7卷 430-434页

作者： Guo Huaicheng Ye Wenhu(Center of environmental sciences , {{2. , beijing 100871 , china) Ctr of Envmtl sciences Peking Univ Beijing China China

ＳｔｕｄｙｏｎｕｒｂａｎｗａｔｅｒｅｎｖｉｒｏｎｍｅｎｔａｌｓｕｐｐｏｒｔｃａｐａｃｉｔｙＧｕｏＨｕａｉｃｈｅｎｇ；ＹｅＷｅｎｈｕ（ＣｅｎｔｅｒｏｆＥｎｖｉｒｏｎｍｅｎｔａｌＳｃｉｅｎｃｅｓ，ＰｅｋｉｎｇＵｎｉｖｅｒ... 详细信息

ＳｔｕｄｙｏｎｕｒｂａｎｗａｔｅｒｅｎｖｉｒｏｎｍｅｎｔａｌｓｕｐｐｏｒｔｃａｐａｃｉｔｙＧｕｏＨｕａｉｃｈｅｎｇ；ＹｅＷｅｎｈｕ（ＣｅｎｔｅｒｏｆＥｎｖｉｒｏｎｍｅｎｔａｌＳｃｉｅｎｃｅｓ，ＰｅｋｉｎｇＵｎｉｖｅｒｓｉｔｙ，Ｂｅｉｊｉｎｇ１００８７...

关键词： water environmental support capacity urban water environment development variablesi supportvariables.

Mixed uncertainty analysis of polycyclic aromatic hydrocarbon inhalation and risk assessment in ambient air of beijing

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Journal of environmental sciences 2008年第4期20卷 505-512页

作者： college of environmental sciences and Engineering, peking university, {{2., china GUO Huaicheng LIU Yong HUANG Kai WANG Zhen ZHAN Xinye 不详 School of Natural Resources and Environment University of Michigan Ann Arbor 48109 USA Department of Civil and Resource Engineering Dalhousie University Halifax NS B3JIZ1 Canada

This article presents the application of an integrated method that estimates the dispersion of polycyclic aromatic hydrocarbons （PAHs） in air, and assesses the human health risk associated with PAHs inhalation. An uncertainty analysis method consisting of three components were applied in this study, where the three components include a bootstrapping method for analyzing the whole process associated uncertainty, an inhalation rate （IR） representation for evaluating the total PAH inhalation risk for human health, and a normally distributed absorption fraction （AF） ranging from 0% to 100% to represent the absorption capability of PAHs in human body. Using this method, an integrated process was employed to assess the health risk of the residents in beijing, china, from inhaling PAHs in the air. The results indicate that the ambient air PAHs in beijing is an important contributor to human health impairment, although over 68% of residents seem to be safe from daily PAH carcinogenic inhalation. In general, the accumulated daily inhalation amount is relatively higher for male and children at 10 years old of age than for female and children at 6 years old. In 1997, about 1.73% cancer sufferers in beijing were more or less related to ambient air PAHs inhalation. At 95% confidence interval, approximately 2.2.309 individual cancer incidences can be attributed to PAHs pollution in the air. The probability of greater than 500 cancer occurrence is 15.3%. While the inhalation of ambient air PAHs was shown to be an important factor responsible for higher cancer occurrence in beijing, while the contribution might not be the most significant one.

关键词： polycyclic aromatic hydrocarbons (PAHs) uncertainty analysis human health risk

Marginal cost pricing for coal fired electricity in coastal cities of china:The case of Mawan Electricity Plant in Shenzhen City, china

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Journal of environmental sciences 2003年第3期15卷 401-412页

作者： ZHANG Shi-qiu, DUAN Yan-xin (Center for environmental sciences, {{2., beijing 100871, china.) Center for environmental sciences Peking University 北京 100871

By developing a GDMOD model to estimate the environmental externalities associated with electricity generation, this project provides a detailed analysis of the damages and costs caused by different pollutants at varying distances from the Mawan Electricity Plant in Shenzhen, china. The major findings of this study can be summarized that (1) environmental damages caused by electricity production are large and are mainly imposed on regions far away from the electricity plant; (2. air pollution is the most significant contributor to the total damages, and SO_2. NOx, and particulate matter are the three major pollutants with highest damages; (3) the damages caused per unit of particulate, NOx, and SO_2.emissions are much higher than pollution treatment and prevention costs. The research results of this project showed that china needs to have a more effective levy system on SO_2. and a more manageable electricity tariff mechanism to internalize the environmental externalities. The results have also implications for pollution control strategies, compensation schemes as well as emission trading arrangements.

关键词： marginal cost pricing environmental damages environmental policy