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The reduction and reuse of composting leachate is an issue of importance in the field of decentralized solid waste management. In this study, composting leachate from source-separated food waste was treated and subsequently used as liquid fertilizer to irrigate Impatiens (Impatiens balsamina). The leachate was altered by adjusting storage time and dilution, and through addition of microbial inocula. For each test case, the effects of irrigation were monitored by analyzing the Impatiens extension degree, numbers of leaves and flowers, dry weight, and photosynthetic pigment content to assess fertilizer efficiency. The main results obtained revealed that the addition of microbial inocula and lengthening of storage times may lower COD concentrations, adjust pH value and maintain a comparatively high level of nutrient contents. By adding microbial inocula, a COD concentration of 9.6% and BOD(5) concentration of 6.7% were obtained for non-treated leachate with the same storage time. COD concentrations in leachate decreased to 69.4% after 36weeks storage. Moreover, composting leachate promoted growth of Impatiens. The dry weight biomass of Impatiens irrigated using treated diluted leachate was 1.15-2.94 times that obtained for Impatiens irrigated using tap water. Lastly, following the irrigation of Impatiens over a short period, soil did not accumulate VOCs and heavy metals to levels exceeding relative standards. Further research on heavy metal and salinity accumulation in plants should be undertaken to meet the needs of large-scale applications., (Copyright 2010 Elsevier Ltd. All rights reserved.)

On the basis of the ancient Chinese human ecological principles, conjugate ecological planning is a kind of social-economic-natural complex ecosystem planning to balance and/or compromise the relationship between environmental and economic development. Eight conjugate planning issues were investigated. It was used in the ecological planning research for Beijing Master Plan revision. The results of East Beijing land-use scenario were shown and ecoservice-based land management strategies were proposed. The executive summary of conjugate ecological planning of Beijing urban ecosystem was introduced in the end.

Abstract A field survey was conducted in a contaminated industrial site of southern Beijing, China to investigate the contents and distribution of the organochlorine pesticides (alpha-, beta-, gamma-, delta-HCH, p,p'-DDT, p,p'-DDE, p,p'-DDD and o,p'-DDT) in the profiles of soil, and a health risk assessment was carried out with CalTOX multimedia exposure model. Results showed that mean concentrations of total hexachlorocyclohexane isomers (HCHs) and total dichlorodiphenyltrichloroethane isomers (DDXs) in soils were in the range of 13.20-148.71 mg/kg, and 3.02-67.43 mg/kg, respectively. Organochlorine pesticides (OCPs) content peaked in the surface and declined in soil profile with depth. The amounts of HCHs in three profiles of soil were larger than DDXs. Composition analysis indicated that there was a trend of degradation of OCPs in the site, but the mean of HCHs and DDXs concentration were over the state warning standard limit (HCHs, 0.50 mg/kg; DDXs, 0.50 mg/kg). According to current land use development, health risk assessment with CalTOX and Monte Carlo analysis showed that health risks mainly came from two exposure pathways: dermal uptake and inhalation, and the total risk values all exceeded the general acceptable health risk value (10-6). The sensitivity analysis indicated that five parameters significantly contributed to total risk.

Markov chain has been widely applied in the study of land use and landscape changes, but its statistical properties were less tested. Based on the land use change data monitored in Beijing, and with Pearson chi-squared goodness-of-fit test, this paper examined the time stability and time independence of Markov chain of land use change. The results indicated that the hypothesis of time stationary and Markov property is not tenable, which meant that the land use change in Beijing was an un-stationary and highly order Markov chain. Pearson chi-squared test was not as restricted a the likelihood ratio test, its transitional probabilities being allowed to be greater than zero, and thus, could be more useful in testing the assumption of homogeneity and independence.

Based on the calculation of actual yield per unit area in 2002, this paper analyzed the ecological footprint and its composition of each province in China. The results showed that there was a significant difference in the ecological footprint and its composition among different provinces, e. g., cropland changed from 0. 078 hm2 x cap(-1) in Shaanxi to 0.126 hm2 x cap(-1) in Beijing, grazing land changed from 0.020 hm2 x cap(-1) in Jiangxi to 0.372 hm2 x cap(-1) in Xizang, forestland changed from 0.020 hm2 x cap(-1) in Guizhou to 0.209 hm2 x cap(-1) in Beijing, fishery area changed from 0.001 hm2 x cap(-1) in Xizang to 0.011 hm2 x cap(-1) in Shanghai, built-up area changed from 0.013 hm2 x cap(-1) in Guizhou to 0.045 hm2 x cap(-1) in Neimenggu, and fossil energy changed from 0.251 hm2 x cap(-1) in Guangxi to 2.854 hm2 x cap(-1) in Shanxi. The eastern and southern provinces were mostly in a state of ecological deficit, while the western and northern provinces were mostly in a state of ecological remainder. As for the relationships among ecological footprint, economic development and technological progress, great difference existed in different provinces, e. g. , the ecological footprint was about 1 hm2 x cap(-1) in Fujian, Henan, Sichuan, Anhui, Yunnan, Shaanxi and Guizhou, while the GDP per capita changed from 1.35 x 10(4) yuan in Fujian to 0.3 x 10(4) yuan in Guizhou, and the ecological footprint per 1 x 10(4) yuan GDP changed from 0.74 hm2 in Fujian to 3.51 hm2 in Guizhou. Therefore, to resolve the conflicts between the shortage of natural resources and the economic development of China, emphasis should be put on the provinces with big ecological footprint per capita, low GDP per capita, and high ecological footprint per 1 x 10(4) yuan GDP. In these provinces, economic growth mode and industrial structure should be changed, dependence of economy on natural resources should be decreased, use efficiency and economic output of natural resources should be improved, and ecological, resources and economic sustainability should be realized.

Based on the Social-Economic-Natural Complex Ecosystem theory, this paper questioned 8 kinds of misunderstandings in current planning, incubation, development, and management of circular economy, which had led to either ultra-right or ultra-left actions in ecological and economic development. Rather than concentrated only on the 3-r micro-principles of "reduce-reuse-recycle", thise paper suggested 3-R macro-principles of "Rethinking-Reform-Refunction" for circular economy development. Nine kinds of eco-integrative strategies in industrial transition were put forward, i.e., food web-based horizontal/parallel coupling, life cycle-oriented vertical/serial coupling, functional service rather than products-oriented production, flexible and adaptive structure, ecosystem-based regional coupling, social integrity, comprehensive capacity building, employment enhancement, and respecting human dignity. Ten promising potential eco-industries in China's near-future circular economy development were proposed, such as the transition of traditional chemical fertilizer and pesticide industry to a new kind of industrial complex for agro-ecosystem management.

By the methods of systematic ecology, and that of Simpson's biodiversity indices in particular, this paper quantitatively analyzed the ecological effects of ten years land use changes in a small town with rapid rural urbanization of Shaoxing County, Zhejiang Province, aimed to provide a scientific basis for healthy development of towns and small cities in China. The results showed that owing to the changes of land use functions, the biodiversity of green plants and soil microorganisms was obviously decreased, and the local climate conditions deteriorated, which was represented by the increase of annual mean air temperature and the decrease of annual mean relative humidity in this town. It was suggested that the long-term ecological changes in biodiversity should be considered in land use with rural urbanization.

In this paper, the concept and connotation of urban green space and ecosystem service were expatiated, and the research advance in ecosystem service of urban green space was reviewed. The studies of ecosystem service of urban green space in overseas were focused on improving the quality of urban environment, maintaining biodiversity, providing amenity values, and ecosystem management; while in China, they were focused on the structure and function of urban green space, green quantity and quality, green equivalent, indicator system evaluation, value assessment, and application of CITYgreen model. The shortages and prospects of the researches on ecosystem service of urban green space were put forward.