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Simulating　sensitivities　of　Changbai　Mountain　forests　to　potential　climate　change

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Journal of Environmental sciences 1996年第3期8卷 354-366页

作者： Yan Xiaodong Zhao Shidong (institute of applied {2.. Chinese academy of sciences,shenyang 110015, China) institute of applied {2. Chinese Academy of Sciences Shenyang 110015 China

Changbai Mt. forest in the northeastern China is both a very important timber resource of China and one of the most typical and less disturbed temperate mixed evergreen coniferous-deciduous forest in the *** this paper, NEWCOP. a gap class model of forest growth and succession was proposed to simulate the sensitivity of the forest in Changbai Mountain to elevate CO_2. warmer temperature and precipitation change. NEWCOP was tested on long term simulation behaviors and short term fitting ability to field data. About the response of forests of Changbai Mountain to possible climate change, NEWCOP suggested that forest landscape go up within long term and forest biomass comes down within short term because of dieback of forest trees.

关键词： gap model climate change forests China.

Techno-economic analysis of municipal wastewater land treatment systems in China

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Journal of Environmental sciences 1993年第1期5卷 16-22页

作者： Huang Chuyuinstitute of Environmental Protection of Jilin Province, Jilin 132.11, ChinaOu Ziqing institute of {2. ecology, Chinese academy of sciences, shenyang 110015, China Inst of Env Protection of Jilin Province Jilin 132011 China China

This paper analyses the capital costs, power consumption and operation costs of municipal wastewater land treatment systems, including rapid infiltration, slow-rate infiltration, overflow and constructed wetland, by means of series engineering design. The results show that land treatment can save 50-70% of capital costs, 80-90% of power and 75-85% of operation costs when compared with secondary treatment.

关键词： land treatment system techno-economy series design cost model.

Resourceful ecological treatment of wastewater in urban ecosystem

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Journal of Environmental sciences 1994年第4期6卷 487-495页

作者： Song Yufang Sun Tieheng Gong Ping Chang Zhijun (institute of applied {2., Chinese academy of sciences, shenyang 110015 . China)

The treatment amount of wastewater is restricted to a small percentage in China. One of thereasons for that is the shortage of funds. Therefore , developing the technology of cost-effective , low energy-consuming and high efficiency is one of the important way to speed up the steps of wastewater *** paper elucidated the principal and charactertics of the resourceful ecological treatment of wastewater. Asuccessful example of resourceful ecological land treatment of wastewater was given. The key points and therelative policies concerning the further development of resourceful ecological treatment of wastewater as asets of technologies have been suggested.

关键词： ecological treatment water resources wastewater pollution.

Compound pollution of Cd,Pb,Cu,Zn,As in plant-soil system and its prevention

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Journal of Environmental sciences 1996年第4期8卷 474-482页

作者： Wu Yanyu Wang Xin Li Ying(institute of applied {2.,Chinese academy of sciences,shenyang 110015, China) institute of applied {2. Chinese Academy of Sciences Shenyang 110015 China

By means of both pot and field tests,this paper studied the contents of Cd,Pb,Cu,Zn and As and their ecological effects on plant-soil *** tissues of crops and soil *** was found that there exist synergistic effect among these five elements,especially for Cd in *** reclaniation of soil polluted by these elements in combination is rather difficult to be carried *** distinctive ecological and chemical behaviors between Cd and As make various reclamation measures less applicable,and thus,further research measures are necessary.

关键词： compound pollution plant-soil system heavy metals.

Changes　of　landscape　pattern　and　its　influence　on　environment　in　Dongling　District，shenyang　City，China

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Journal of Environmental sciences 1996年第4期8卷 466-473页

作者： Zhao Yi Liu Zhenguo Xu Lan (institute of applied {2.,Chinese academy of sciences,shenyang 110015,China) institute of applied {2. Chinese Academy of Sciences Shenyang 110015 China

Dongling District of shenyang City is an ecotone between city and countryside. Human disturbance causes serious changes of the landscape pattern studed by using indices of landscape pattern: proportion in land cover types,average area and number of patches,fractal dimension of patches,indices of diversity, dominance and contagion and index of human *** are many changes of the landscape pattern of Dongling District for the last 30 *** landscape pattern is breaking, the diversity is increasing and the dominance is *** are different fractal dimension and contagion in distinct geomorphological *** changes of landscape pattern bring some beneficial results but causes deterioration of ecological environment.

关键词： landscape pattern ecotone ecological environment.

Competitive and cooperative adsorption of arsenate and citrate on goethite

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Journal of Environmental sciences 2009年第1期21卷 106-112页

作者： SHI Rong,JIA Yongfeng,WANG Chengzhi institute of applied {2.,Chinese academy of sciences,shenyang 110016,China institute of applied {2. Chinese Academy of Sciences Shenyang 110016 China

The fate of arsenic in natural environments is influenced by adsorption onto metal （hydr）oxides. The extent of arsenic adsorption is strongly affected by coexisting dissolved natural organic acids. Recently, some studies reported that there existed competitive adsorption between arsenate and citrate on goethite. Humic acid is known to interact strongly with arsenate by forming complexes in aqueous solution, hence it is necessary to undertake a comprehensive study of the adsorption of arsenate/citrate onto goethite in the presence of one another. The results showed that at the arsenate concentrations used in this study （0.006-0.2. mmol/L）, citrate decreased arsenate adsorption at acidic pH but no effect was observed at alkaline pH. In comparison, citrate adsorption was inhibited at acidic pH, but enhanced at alkaline pH by arsenate. This was probably due to the formation of complex between arsenate and citrate like the case of arsenate with humic acid. These results implied that the mechanism of the adsorption of arsenate and citrate onto goethite in the presence of one another involved not only competition for binding sites, but the cooperation between the two species at the watergoethite interface as well.

关键词： adsorption arsenate citrate goethite

Detecting forest landscape boundary between Mountain Birch and evergreen coniferous forest in the northern slope of Changbai Mountain

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Journal of Environmental sciences 2003年第2期15卷 182-186页

作者： CHANG Yu+1, BU Ren-cang+1, HU Yuan-man+1, XU Chong- gang+1, WANG Qing-li+2.(1. institute of applied {2., Chinese academy of sciences, shenyang 110016, China. 2. shenyang Branch, CAS) institute of applied {2. Chinese Academy of Sciences Shenyang 110016 China shenyang Branch CAS Shenyang China

Boundaries between different forest types in Changbai Mountain Eastern China are results from complex interactions between forest ecosystems, topography, and geomorphology. Detecting and quantifying the transitional zones are highly important since high environmental heterogeneity and biodiversity are often found within these zones. In this study, we used GIS and multivariate statistics techniques(PCA and MSWA) to analyze data from Landsat TM satellite imageries and quantitatively determined the positions and widths of the landscape boundary between mountain birch and evergreen coniferous forests in the northern slope of Changbai Mountain. The results showed that the widths of the landscape boundary ranges from 30—50m while using the MSWA or/and PC method. Such detected widths are consistent with field transect data that suggests a 50m transitional zone width. The results further suggest that TM data can be used in combination with GIS and statistical techniques in determining forest landscape boundaries; MSWA is more reliable than PCA, while PCA can also be used to determine the landscape boundary when transects are properly located.

关键词： Changbai Mountain forest landscape boundary PCA & MSWA

Greenhouse gas emissions from a constructed wetland for municipal sewage treatment

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Journal of Environmental sciences 2002年第1期14卷 27-33页

作者： TAI Pei dong 1, LI Pei jun 1 , SUN Tie heng 1, HE Yao wu 1, ZHOU Qi xing 1 GONG Zong qiang 1, Motoyuki Mizuochi 2. Yuhei Inamori 2.(1 institute of applied {2., Chinese academy of sciences, shenyang 110015, China. 2.National Insti institute of applied {2. Chinese Academy of Sciences 110015 China. E-mail:[email protected] National institute for Environmental Studies 16-2 Onagawa Tsukuba Ibaraki 305 Japan

The fluxes of greenhouse gases (methane and nitrous oxide) emission from a constructed wetland in the Eastern China as municipal sewage treatment were measured from June 1999 to August 2.00 by the closed chamber method. The constructed wetland for municipal sewage treatment is a significant source of methane, up to 976 6×10 6 g CH 4/a, which was emitted from the constructed wetland with the area of 495000 m 2.and wastewater loading rate of 12.00 m 3/d. Its daily mean methane flux reached 5 2. g CH 4/(m 2.d), 2.0 times as much as that in natural wetland in the same latitude region. 2.7 8 mg CH 4 was produced from the treatment of 1 liter wastewater, up to 700—1000 times as much as that in the secondary treatment. The emission of nitrous oxide from the constructed wetland is not higher than that from secondary treatment of wastewater, only 0 07 mgN 2./L.

关键词： greenhouse gas emission constructed wetland municipal sewage methane nitrous oxide

Compound contamination and secondary ecological effects of Cd and As in soil－alfalfa ecosystems

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Journal of Environmental sciences 1994年第3期6卷 330-336页

作者： Zhou Qixing Gao Zhengmin(institute of applied {2., Chinese academy of sciences),shenyang 10015,China)

d and As both have harmful effects on the growth,development and seed germination of alfalfa, especially in such a condition as the coexistence of Cd and As in soil environment The research using the pot-culture imitative method first found that if soil was simultaneously polluted by Cd and As,function of alfalfa absorbing Cd from soil may be promoted because of the existence of As,in conversely,Cd may inhibit alfalfa plant from absorbing As It was also found that secon- dary ecological effects were most likely to be brought out due to the coexistence of Cd and As. For example,alfalfa is passive to excessively absorb Cu and Pb .The harmful effects undoubtedly intensi- fy the contamination of alfalfa, The results showed that the mechanism of the interaction among Cd,As,Pb and Cu in soil-alfalfa ecosystems is very complicated.

关键词： compound contamination,ecological effects,Cd As soil.