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  • Articles
    WANG Guoqian, WANG Xuequan, WU Bo, LU Qi
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    China is severely impacted by desertification. Of its territory, 34.6% — some 3.32 million km2 — is classified as drylands1) (including arid, semi-arid and semi-humid arid areas). Of the drylands, 2.62 million km2 meets the UNCCD definition of desertified land. These desertified lands spread across 18 provinces and account for 27.33% of the country's landmass. Over 400 million residents are affected, causing an annual direct economic loss exceed 64 billion CNY. China’s desertification mitigation began in late 1950s. Through a number of high-profile programs – “Three-North Shelterbelt Development Program”, “National Program on Combating Desertification”, “Sandification Control Program for Beijing and Tianjin Vicinity”, and “Croplands to Forests or Grasslands Program” launched between 1978 and 2000, the Government of China has poured on average 0.024% of the country’s annual GDP into desertification mitigation and, as a result, some 20% of desertified lands have been brought under control. Approximately 50×104 km2 of the existing desertified lands are considered restorable given current technology. When the potential desertification increments induced by global warming are taken into account, total desertified area within planning horizon is projected to range from 55×104 to 100×104 km2. With the approximate restoration rate of 1.5×104-2.2×104 km2 y-1, China’s anti-desertification battle is expected to last 45-70 years. The current strategic plans set restoration targets at 22×104 km2 by 2015, with an additional 33×104 km2 by 2030, and the final 45×104 km2 of the 100×104 km2 restored by 2050. Through examining state investment in mitigation and current rehabilitation strategies, the paper recommends: (i) boardening the previous sectoral perspective to a multi-stakeholder approach; (ii) setting priority zones within the restorable area, and establishing National Special Eco-Zones; (iii) steering state investment from government investment in tree plantations to acquisition of planted/greened areas; and (iv) introducing preferential policies in favor of sandy land restoration, including extending land tenures to 70 years and compensating for ecological services.
  • Articles
    LI Xiaowei, FU Guobin, Melanie J. B. ZEPPEL, YU Xiubo, ZHAO Gang, Derek EAMUS, YU Qiang
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    Fire weather indices have been widely applied to predict fire risk in many regions of the world. The objectives of this study were to establish fire risk probability models based on fire indices over different climatic regions in China. We linked the indices adopted in Canadian, US, and Australia with location, time, altitude, vegetation and fire characteristics during 1998-2007 in four regions using semiparametric logistic (SPL) regression models. Different combinations of fire risk indices were selected as explanatory variables for specific regional probability model. SPL regression models of probability of fire ignition and large fire events were established to describe the non-linear relationship between fire risk indices and fire risk probabilities in the four regions. Graphs of observed versus estimated probabilities, fire risk maps, graphs of numbers of large fire events were produced from the probability models to assess the skill of these models. Fire ignition in all regions showed a significant link with altitude and NDVI. Indices of fuel moisture are important factors influencing fire occurrence in northern China. The fuel indices of organic material are significant indicators of fire risk in southern China. Besides the well skill of predicting fire risk, the probability models are a useful method to assess the utility of the fire risk indices in estimating fire events. The analysis presents some of the dynamics of climate-fire interactions and their value for management systems.
  • Articles
    WU Wei, James S. CLARK, James M. VOSE
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    We have applied a full hierarchical Baysian (HB) model to simulate streamflow at the Coweeta Basin that drains western North Carolina, USA under a doubled CO2 climate scenario. The full HB model coherently assimilated multiple data sources and accounted for uncertainties from data, parameters and model structures. Full predictive distributions for streamflow from the Bayesian analysis indicate not only increasing drought, with substantial decrease in fall and summer flows, and soil moisture content, but also increase in the frequency of flood events when they were fit with Generalized Extreme Value (GEV) distribution and Generalized Pareto Distribution (GPD) under this doubled CO2 climate scenario compared to the current climate scenario. Full predictive distributions based on the hierarchical Bayesian model, compared to deterministic point estimates, is capable of providing richer information to facilitate development of adaptation strategy to changing climate for a sustainable water resource management.
  • Articles
    LIU Jiajun, DONG Suocheng, LI Yu, MAO Qiliang, LI Jun, WANG Junni
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    Energy is an important production factor. When more energy is put into production activities, labor productivity increases and the economy and social development improve. Industrial structural change is an important factor that affects the growth of regional energy efficiency. In modern development, industrial structural improvement is closely related to regional energy efficiency and the status of industrial structure. Energy efficiency can together reflect a country’s development level, sustainable development and the direction in which its economy will head. This paper discusses the contribution of industrial structural adjustment to regional energy efficiency growing with a spatial perspective. This study based on 31 mainland provinces in China, uses statistics of industrial structure and corresponding energy utilization data, adopting mathematic model and spatial analysis approaches, reveals that the 31 provinces in China differed in their contribution to industrial structural adjustment to regional energy efficiency. The outcome reflected contribution is obvious in those provinces with appropriate industrial structure and good economies or the ones developed late as well as the undeveloped middle and western provinces that are in initial stage of industrial restructuring. But that is not obvious in those provinces with the undeveloped leading industries, with weak economic basis, and with a relatively low level of industrial structure.
  • Articles
    CHEN Lajiao, ZHU Axing, QIN Chengzhi, LIU Junzhi
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    Critical source areas (CSAs), characterized by severe soil erosion and high sediment yield, are considered to have a high priority for conservation. How to identify CSAs and assess the effectiveness of conservation practices is a key issue in site-specific watershed management. The Soil and Water Assessment Tool (SWAT) model is a useful tool for site-specific conservation practices design and several studies have attempted to identify CSAs based on watershed models. However, limited research has reported about the effectiveness of conservation practices targeting CSAs. The aim of this study was to assess the effectiveness of conservation pracrices targeted on CSAs using the SWAT model. CSA was firstly identified based on the 4-year average yearly erosion of each HRU. Appropriate soil conservation practices were then designed for the CSAs. A scenario with conservation practices for the whole watershed was also established as the contrasting counter parts scheme and then compared to the outcome of CSA-targeted conservation pracrices. The result shows that SWAT can accurately simulate sediment yield in the study area. CSAs were mainly located in slope farmland areas and steep gullies, coinciding with the distribution of land use and slope. The identified CSA covered 20% of the HRUs and contributed on average 44% of sediment yield. Conservation practices targeting CSAs had higher sediment reduction effectiveness (24 115 t km-2 y-1) than conservation practice covering the whole watershed (20 290 t km-2 y-1). Thus conservation practices targeting CSAs are more effective than broad conservation practices. We conclude that soil conservation practices focusing on CSAs do increase sediment reduction effectiveness. Targeting the placement of soil conservation practices based on the CSAs concept will assist water quality control in watersheds.
  • Articles
    YIN Jie, WU Shaohong, DAI Erfu
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    Guangdong is a developed province in China, but suffers from frequent typhoon disasters which cause great economic loss. Quantitative regional risk assessment of typhoon disasters is important for disaster prevention and mitigation. According to direct economic loss and typhoon intensity information, we established a typhoon disaster loss rate curve using data from 1954 to 2008. Based on GIS spatial module, the economic vulnerabilities of different intensity typhoons were calculated for 98 counties in Guangdong Province. Different intensity typhoon landing frequencies in Guangdong were also calculated, and used to indicate typhoon disaster probability. A risk assessment model was established to assess economic loss risk under different intensity typhoons in Guangdong. The results show that economic loss risk caused by typhoon is more than 10 thousand million CNY; according to typhoon intensity grade, economic risk is up to 10.467, 14.429, 7.753 and 13.591 thousand million CNY for slight, light, medium and severe typhoons, respectively. The Pearl River Delta is the highest risk region, especially Guangzhou, Dongguan, Shenzhen, Zhongshan and Zhuhai. Risk value decreases from Pearl River coastal outfall to the inland in a radial pattern. Inland areas far from coastal counties have lower risk, and the risk value is less than 50 million CNY. When typhoon intensity increases from slight to medium, the risk in western is higher than in eastern parts, but when typhoons become to severe, the risk value in eastern Guangdong part is higher than in the west.
  • Articles
    CHEN Bo, OUYANG Zhu, ZHANG Shaohui
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    Field topography or microtopography plays an important role in achieving acceptable performance in border irrigation. Extension of conservation tillage across the North China Plain has resulted in change in field bottom configuration. This study defined regular bottom configuration for border irrigation, and introduced three regular bottom configurations: border-strip irrigation (BSI), border-furrow irrigation (BFI) and rill irrigation (RI). The effects of regular bottom configuration on the hydraulic process and irrigation performance were evaluated by field experiments and a WinSRFR3.1 model. Results suggest that the WinSRFR3.1 model was capable of the simulation of BFI and RI, and that the hydraulic process and irrigation performance were diverse among BSI, BFI, and RI. BSI had the highest infiltration rate while BFI had the lowest infiltration rate; BSI took the most time to complete the water advance while BFI took the least time. As a result, BSI showed the worst irrigation performance while BFI gave the best irrigation performance. Different field bottom configurations mainly accounted for differences. We conclude that regular field bottom configuration is an important factor for acceptable performance in border irrigation.
  • Articles
    ZHANG Yan, LIU Suxia, CHEN Junfeng
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    Water resource allocation (WRA) is a useful but complicated topic in water resource management. With the targets set out in the Plan of Newly Increasing Yield (NIY) of 10×1011 Jin (1 kg=2 Jin) from 2009 to 2020, the immediate question for the Songhua River Region (SHRR) is whether water is sufficient to support the required yield increase. Very few studies have considered to what degree this plan influences the solution of WRA and how to adapt. This paper used a multi-objective programming model for WRA across the Harbin region located in the SHRR in 2020 and 2030 (p=75%). The Harbin region can be classified into four types of sub-regions according to WRA: Type Ⅰ is Harbin city zone. With rapid urbanization, Harbin city zone has the highest risk of agricultural water shortage. Considering the severe situation, there is little space for Harbin city zone to reach the NIY goal. Type Ⅱ is subregions including Wuchang, Shangzhi and Binxian. There are some agricultural water shortage risks in this type region. Because the water shortage is relatively small, it is possible to increase agricultural production through strengthening agricultural water-saving countermeasures and constructing water conservation facilities. Type Ⅲ is sub-regions including Acheng, Hulan, Mulan and Fangzheng. In this type region, there may be a water shortage if the rate of urbanization accelerates. According to local conditions, it is needed to enhance water-saving countermeasures to increase agricultural production to a certain degree. Type Ⅳ is sub-regions including Shuangcheng, Bayan, Yilan, Yanshou and Tonghe. There are good water conditions for the extensive development of agriculture. Nevertheless, in order to ensure an increase in agricultural production, it is necessary to enhance the way in which water is utilized and consider soil resources. These results will help decision makers make a scientific NIY plan for the Harbin region for sustainable utilization of regional water resources and an increase in agricultural production.
  • Reports
  • Reports
    HE Hanming, YANG Lei, ZHAO Lihua, WU Han, FAN Liming, XIE Yong, ZHU Youyong, LI Chengyun
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    Intercropping can improve field microclimates, decrease the incidence of crop diseases, and increase crop yields, but the reasons for this remain unknown. Solar radiation is the most important environmental influence. To understand the mechanisms of intercropping we established an experiment consisting of three cropping patterns: a monocropping control (treatment A) and two intercropping treatments (B: two rows of maize and two rows of soybean intercropping; C: two rows of maize and four rows of soybean intercropping). Results show that compared to monocropping, intercropping increased the amount of light penetrating to inferior leaves in maize plants. Light intensity reaching maize plants at the heading stage in intercropping increased over two-fold at 30 cm above ground and 10-fold at 70 cm above ground, compared with monocropping. At the flowering to maturity stage, light intensity at 110, 160 and 210 cm above ground among maize plants was greatly increased in intercropping compared with monocropping, by some five-fold, two-fold and 12%, respectively. Moreover, light intensity declined more slowly at the measured heights in the intercropping system compared with monocropping. From the 7–18th leaf, light intensity per leaf increased two-fold in intercropping compared with monocropping. Daily light duration increased more than a mean of 5 h per day per leaf in intercropping compared with monocropping. The biological characters of maize including thousand kernel weight, yield per plant and area of ear leaves were all greater in intercropping than monocropping. These results suggest that, for maize, intercropping improves light density and duration significantly and this may contribute to biomass and yield increases.
  • Reports
    ZOU Yi, FENG Jinchao, XUE Dayuan, SANG Weiguo, Jan C. AXMACHER
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    Terrestrial arthropods are extremely important ecosystem components. The choice of best approaches to collect the wide range of terrestrial arthropods has been a topic of long-lasting debates. This article provides a brief overview of common sampling methods for terrestrial arthropod assemblages. We divide sampling methods into three main categories: passive sampling methods without any “activity density” bias, passive sampling methods with an “activity density” bias, and active sampling methods with inherent “activity density” and often further species-dependent biases, discussing their individual advantages and shortcomings as basis for biodiversity studies and pest control management. The selection of the optimal sampling methods depends strongly on the purpose of individual studies and the ecology and behavior of the arthropod groups targeted. A combination of different suitable methods is highly recommended in many cases.
  • Reports
    DENG Minzhen
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    Buildings have contributed to the energy shortage, pollution and global climate change. To promote green buildings is the way access to the sustainable development. Currently, China has issued some regulations and systems to boost the green building. However, problems lie in China and the systems are not effective. USA and EU have rich experiences and fairly sophisticated legislation and policies to develop green building. China may get some lessens from these countries. This paper will make an overview of legal framework and main system of green building in China, then, analyses some important legal systems and typical case related green building in the USA and EU. Further, problems were pointed out in the China based on the comparative analysis of these countries. Lastly, according to the condition in China and lessons from USA and EU, this paper will put some suggests to promote green building, such as, take some measures to enhance the awareness of the stakeholders, create multiincentive tools and so on.
  • Synopsis
  • Synopsis
    2012, 3(2): 192-192.
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    With the health of the earth’s ecosystems increasingly under threat, due to a growing population, high rates of deforestation and transformation into agricultural and pasturelands, the role of ecosystem management has become more important than ever.