Response to environmental flows in the lower Tarim River, Xinjiang, China: ground water

In China's west since the 1950s large-scale ecosystem degeneration has occurred through water diversions for agricultural purposes. Since 2000, 1038 x 10(6) m(3) of water have been released into the Tarim River with the result that water reached the terminal Taitema Lake for the first time in 30 years. This environmental flow raised water-table levels along 350 km of the river. To assess the response of the water-table, a comparison "pristine" site is compared with downstream monitored sites. The results show huge changes in water-table levels. The study verifies that the water-table is extremely responsive to environmental flows, that strong internal similarities exist along the length of the river, and that the effect on the water-table and hence likely riparian vegetation recovery can be tentatively predicted. The actual impacts of the restoration strategy are less than those originally expected politically, socially and within the scientific community. We make recommendations on more effective release strategies.     

塔里木河中下游的生态环境问题初探

水资源的不合理开发和乱砍滥伐等人为因素导致了塔里木河流域的生态失衡,影响了南疆,甚至整个新疆的经济和社会发展。通过对塔里木河中、下游的生态环境存在问题的综述,探讨了该流域生态环境恶化的主要原因,并对它的保护和改善提出了建议。     

塔里木河下游生态输水的效应

根据塔里木河下游的地下水位、植物调查数据,对比分析了塔里木河下游生态输水后地下水位、生物量、物种多样性变化。结果表明：实施生态输水工程后,地下水位对生态输水的响应显著,地下水位逐渐抬升,下降趋势得以控制。草本植物生物量的变化趋势与每次输水量变化趋势基本一致,即随着输水量的增加草本植物的生物量也相应增加,草本植物生物量对生态输水的响应程度与输水的时间、输水量的多少有密切关系。地下水位埋深上升,物种多样性也呈上升趋势,但二者并不是同步,物种多样性上升趋势滞后于地下水位的上升,这表明地下水位的抬升有利于植物多样性的增加,但是地下水位变化对植物多样性的影响是一个渐变的过程。     

尉犁县土地开发对塔里木河中下游生态环境的影响及其保护对策分析

阐明了土地开发对塔里木河中下游生态环境的影响,研究分析其原因并提出了相应的对策。     

From pioneering to organised business: the development of ecological farming in China

ABSTRACT

Small-scale ecological farming and their associated alternative food networks, are increasingly important in China, as a response to poor farm incomes and as a contribution to widespread concerns about environmental degradation and food safety. However, despite the enormous market potential and the notable success of some ventures, this type of farming remains at the margins, with many businesses struggling to develop beyond their start-up phase and consumers struggling to build confidence in the new produce and routes to market. Many of these farms display the classic elements of pioneer businesses, including high reliance on charismatic individuals, insecure land rights, high transaction and monitoring costs and fragile routes to market. Empirically, many of these businesses fail because they cannot grow out of the pioneer phase before the pioneer grows tired of the business. While this is a problem for all small businesses, it is particularly acute in business sectors like ecological farming in China, where there is little evidence of suitable and sustainable developmental models. Using Bernardus Lievegoed's work on organisational development applied to two case study farms, we suggest that there are Western developmental models that are applicable to small-scale ecological farming and that have the potential to offer insights into how this might be achieved with Chinese characteristics. We conclude by arguing that, Chinese ecological farms have to plan explicitly for a form of development that allows them to remain committed to their ideals while moving them away from dependence on charismatic people, family labour and volatile customer bases.     

塔河下游胡杨和红柳自然恢复的土壤条件初步研究

主要研究了塔里木河下游中段，随塔里木河下游应急放水，河滩地的胡杨和红柳种子出苗与根系吸水后重新发芽生长等自然恢复措施的同时，分析了河床自然淹水条件下林灌草甸土的水分，盐分和肥力变化状况及其对胡杨和红柳乔灌木植被种子出苗和地下水位的升高对升灌木根系重新发芽生长的效果。根据对塔河下游定点观测取样分析结果来看，淹水林灌草甸土不但是自然恢复保护塔河下游绿色走廓的根本基础，而且是恢复与保护绿色走廓的一项有效措施。     

An ecological perspective on theory, methods, and analysis in environmental psychology: Advances and challenges

Over the course of environmental psychology's brief history, there has been an interest in ecologically oriented approaches to theory and research. Based on this work, this paper identifies a set of six principles of ecological analysis that present theoretical, methodological, and analytic challenges to future research in environmental psychology. These challenges include the theoretical treatment of the multiple contexts within which human experience and behavior occurs, the need for sampling both persons and environments, the modeling of moderating and mediating processes, the issue of self-selection into and out of different settings, the necessity of considering temporal factors in environmental research, reliance on single methods (e.g., verbal report) in data generation, cross-sectional and longitudinal research designs, and the need for greater use of statistical techniques developed for contextual (multi-level) research. These issues are discussed and illustrated using recent developments in environmentally oriented research. The paper concludes with a set of 11 recommendations for the future.     

塔里木河下游工程输水后的生态效益分析

以塔里木河下游为研究区域,分析了生态输水工程实施以来该区地下水埋深、水质、植被生长状况的不同响应程度。研究表明:生态输水工程使得原本较低的地下水位在一段时间内得到抬升,局部生态环境得到改善,尤其在输水中期(2003-2005年),植被物种组成发生变化,物种多样性增加,植被盖度提高,地下水水质有所好转;但2007年以后,尤其是2008年,随着输水的间断,下游地下水位开始回落,草本植物物种数量又开始减少,因此,生态输水工程必须持续进行才能真正挽救塔里木河下游生态环境。     

Public support for ecosystem restoration in the Hudson River Valley,USA

We applied the Theory of Planned Behavior to help understand the relationships between environmental beliefs, support for ecosystem restoration actions, and willingness to pay (WTP) for restoration and protection goals in the Hudson River estuary, New York State, USA. We conducted a mail survey with 3,000 randomly-chosen local residents of the Hudson River estuary in the fall of 1999. As hypothesized, the broad ecosystem restoration goals of the Hudson River Estuary Action Plan were more strongly supported than the corresponding specific implementation actions. We found that beliefs and past behavior were better explanatory variables than sociodemographic characteristics for explaining people's support for ecosystem restoration actions and WTP for restoration and protection goals. Because ecosystem restoration goals appear to be more generally acceptable than specific restoration actions, proponents of restoration programs should not become complacent about the need for active public outreach and involvement even if initial restoration program discussions have been low in controversy. Efforts to assess and foster support for ecosystem restoration should be targeted toward audiences identified on the basis of beliefs and past behaviors rather than on sociodemographic characteristics.     

Progress, Challenges and Prospects of Eco-Hydrological Studies in the Tarim River Basin of Xinjiang, China

Eco-hydrological research in arid inland river basins has been a focus of geologists and ecologists as it is crucial for maintaining the sustainable development of socio-economy, particularly in ecologically vulnerable areas. Based on the research work carried out in the Tarim River basin of Xinjiang, northwestern China, this paper summarizes synthetically the climate change and associated responses of water resources in the mountainous area, land use and land cover in the oasis, and plants responding to environmental stresses in the desert area of the river basin. Research gaps, challenges, and future perspectives in the eco-hydrological studies of the Tarim River basin are also discussed.     

Effect of Human Activities on Overall Trend of Sedimentation in the Lower Yellow River,China

The Yellow River has been intensively affected by human activities, particularly in the past 50 years, including soil–water conservation in the upper and middle drainage basin, flood protection in the lower reaches, and flow regulation and water diversion in the whole drainage basin. All these changes may impact sedimentation process of the lower Yellow River in different ways. Assessing these impacts comprehensively is important for more effective environmental management of the drainage basin. Based on the data of annual river flow, sediment load, and channel sedimentation in the lower Yellow River between 1950 and 1997, the purpose of this paper is to analyze the overall trend of channel sedimentation rate at a time scale of 50 years, and its formative cause. It was found in this study that erosion control measures and water diversion have counteractive impacts on sedimentation rate in the lower Yellow River. Although both annual river flow and sediment decreased, there was no change in channel sedimentation rate. A regression analysis indicated that the sedimentation in the lower Yellow River decreased with the sediment input to the lower Yellow River but increased with the river flow input. In the past 30–40 years, the basin-wide practice of erosion and sediment control measures resulted in a decline in sediment supply to the Yellow River; at the same time, the human development of water resources that required river flow regulation and water diversion caused great reduction in river flow. The former may reduce the sedimentation in the lower Yellow River, but the reduction of river flow increased the sedimentation. When their effects counterbalanced each other, the overall trend of channel sedimentation in the lower Yellow River remained unchanged. This fact may help us to better understand the positive and negative effects of human activities in the Yellow River basin and to pay more attention to the negative effect of the development of water resources. The results of this study demonstrate that, if the overuse of river water cannot be controlled, the reduction of channel sedimentation in the lower Yellow River cannot be realized through the practice of erosion and sediment control measures.     

Floristic Characteristics and Biodiversity Patterns in the Baishuijiang River Basin,China

A case study was conducted on the forest ecosystem in the Baishuijiang River basin of China to reveal the influences of environmental factors and human disturbance on the floristic characteristics and biodiversity patterns. Field surveys of the floristic composition, environmental factors, and disturbance factors were conducted along an elevation gradient, and the relationships between biodiversity pattern and environmental factors were analyzed using CCA (canonical correspondence analysis). The results showed that the floristic composition of higher plants consisted of 197 families, 796 genera, 2165 species, 19 subspecies, 239 varietas, and 12 forma, and it was characterized by the multi-geographic composition and by the transition from tropical to temperate zones. Along an elevation gradient, the variations in α and β diversity were best described by a bimodal curve, and the peak values occurred at middle elevations. The CCA indicated that the elevation had the greatest influence on the biodiversity pattern, followed by the topographic index, slope direction, slope, slope position, slope shape, and vegetation coverage. In addition, human disturbance has greatly impacted the floristic composition and biodiversity patterns, and the biodiversity indices were higher with intermediate disturbance at middle elevations compared to higher and lower disturbances at low and high elevations, respectively. This reflected a disturbance–diversity pattern and thus revealed the obvious importance to maintain the intermediate disturbance for biodiversity conservation.     

A methodology of characterizing status and trend of land changes in oases: a case study of Sangong River watershed, Xinjiang, China

Land change is often studied with Markov models to develop a probability transition matrix. The existing methods dependent on such matrixes cannot effectively characterize some important aspects associated with land change such as status, direction, trend and regional variations. This study presents mathematical models to quantify these elements, defining unbalanced, quasi-balanced and balanced status, one- and two-way transitions and the rising or falling trends. Using these models and remote-sensing imageries, the landscape was studied for a case area, the oasis of Sangong River in Xinjiang, Northwest China where typical arid conditions prevail. Land expansion and contraction among various land types and for the entire oasis were analyzed for the periods of 1978-1987, 1978-1998 and 1987-1998. The changes were closely related to a strong economic growth after the land-reform campaign and adoption of the market economy in China in the 1980s to early 1990s, a process not strictly Markovian that requires stationarity and randomness. Information on land-change status and trend is important for a better understanding of the underlying driving processes but also for land-use planning and decision-making.     

Adaptive environmental management of tourism in the Province of Siena, Italy using the ecological footprint

Adaptive management as applied to tourism policy treats management policies as experiments that probe the responses of the system as human behavior changes. We present a conceptual systems model that incorporates the gap between observed and desired levels of the ecological footprint with respect to biocapacity. Addressing this gap (or 'overshoot') can inform strategies to increase or decrease visitation or its associated consumption in the coming years. The feedback mechanism in this conceptual model incorporates a gap between observed and desired ecological footprint levels of tourists and residents. The work is based on longer-term and ongoing study of tourism impacts and ecological footprint assessments from the SPIN-Eco Project. We present historical tourism and environmental data from the province of Siena, Italy and discuss the use of discrete, static environmental indicators as part of an iterative feedback process to manage tourism within biophysical limits. We discuss a necessary shift of emphasis from certain and static numbers to a process-based management model that can reflect slow changes to biophysical resources. As underscored by ecological footprint analysis, the energy and material use associated with tourism and local activity can erode natural capital foundations if that use exceeds the area's biological capacity to support it. The dynamic, and iterative process of using such indicators as management feedback allows us to view sustainability more accurately as a transition and journey, rather than a static destination to which management must arrive.     

从生态学的角度分析温瑞塘河的文化积淀和水环境污染的治理

本文描述了温瑞塘河的文化和目前的面源污染情况,试图剖析唐宋时期的环境结构,并描述这些文化因子在温瑞塘河的形成和发展的过程中,如何嵌入当地的生态系统,推进整个系统的发展和自身的积累,以及温瑞塘河的污染现状。通过分析,提出了几点从生态学的角度,结合文化、经济来管理和治理温瑞塘河的有效措施。     

Projecting Cumulative Benefits of Multiple River Restoration Projects: An Example from the Sacramento-San Joaquin River System in California

Despite increasingly large investments, the potential ecological effects of river restoration programs are still small compared to the degree of human alterations to physical and ecological function. Thus, it is rarely possible to “restore” pre-disturbance conditions; rather restoration programs (even large, well-funded ones) will nearly always involve multiple small projects, each of which can make some modest change to selected ecosystem processes and habitats. At present, such projects are typically selected based on their attributes as individual projects (e.g., consistency with programmatic goals of the funders, scientific soundness, and acceptance by local communities), and ease of implementation. Projects are rarely prioritized (at least explicitly) based on how they will cumulatively affect ecosystem function over coming decades. Such projections require an understanding of the form of the restoration response curve, or at least that we assume some plausible relations and estimate cumulative effects based thereon. Drawing on our experience with the CALFED Bay-Delta Ecosystem Restoration Program in California, we consider potential cumulative system-wide benefits of a restoration activity extensively implemented in the region: isolating/filling abandoned floodplain gravel pits captured by rivers to reduce predation of outmigrating juvenile salmon by exotic warmwater species inhabiting the pits. We present a simple spreadsheet model to show how different assumptions about gravel pit bathymetry and predator behavior would affect the cumulative benefits of multiple pit-filling and isolation projects, and how these insights could help managers prioritize which pits to fill.     

Measuring the impact of prefabrication on construction waste reduction: An empirical study in China

Prefabrication has been widely regarded as a sustainable construction method in terms of its impact on environmental protection. One important aspect of this perspective is the influence of prefabrication on construction waste reduction and the subsequent waste handling activities, including waste sorting, reuse, recycle, and disposal. Nevertheless, it would appear that existing research with regard to this topic has failed to take into account its innate dynamic character of the process of construction waste minimization; integrating all essential waste handling activities has never been achieved thus far. This paper proposes a dynamic model for quantitatively evaluating the possible impacts arising from the application of prefabrication technology on construction waste reduction and the subsequent waste handling activities. The resulting model was validated based on an actual building project in Shenzhen, China.The simulation results of the design scenarios indicate that the policy on providing subsidy for each square meter of the prefabrication adopted in the construction would have more significant effect on promoting the use of prefabrication and improving the performance of construction waste reduction compared to the increase of income tax benefits. The results also show that (1) interaction exists among different management measures, and (2) the combined effect of multiple policies is larger than the simple sum of their individual impacts, indicating the need for comprehensive consideration on the combined effect of these potential polices. This paper demonstrates the potential benefits of using a system dynamics approach in understanding the behavior of real-world processes. The developed model not only serves as a practical tool for assessing the impact of off-site prefabrication on construction waste reduction and the corresponding waste handling activities, but also help provide a valuable reference to policy makers through the comparison of simulation results generated under various scenarios such that the best policy mix can be identified prior to production.     

Factors influencing private and public environmental protection behaviors: results from a survey of residents in Shaanxi, China

Currently one of the largest and most rapidly developing countries, China also has some of the world's most severe environmental problems. China will most likely need to use all of the potential major strategies currently available to solve the country's huge environmental challenges, including promoting individual conservation behavior through educational campaigns and encouraging public environmental advocacy. This paper summarized the findings of a survey of 347 residents of Shaanxi province on environmental attitudes and behaviors. The survey found generally high levels of environmental knowledge and high recognition of the seriousness of environmental issues, moderate levels of individual actions supporting environmental resource conservation and low levels of public environmental behaviors, particularly for organized public advocacy. Further analysis indicated that the perceived importance of environmental protection is the most important factor influencing individual environmental resource conservation, but not public advocacy behaviors. Implications for environmental campaigns are discussed.     

Reconciling Environmental and Flood Control Goals on an Arid-Zone River: Case Study of the Limitrophe Region of the Lower Colorado River in the United States and Mexico

Arid zone rivers have highly variable flow rates, and flood control projects are needed to protect adjacent property from flood damage. On the other hand, riparian corridors provide important wildlife habitat, especially for birds, and riparian vegetation is adapted to the natural variability in flows on these rivers. While environmental and flood control goals might appear to be at odds, we show that both goals can be accommodated in the Limitrophe Region (the shared border between the United States and Mexico) on the Lower Colorado River. In 1999, the International Boundary and Water Commission proposed a routine maintenance project to clear vegetation and create a pilot channel within the Limitrophe Region to improve flow capacity and delineate the border. In 2000, however, Minute 306 to the international water treaty was adopted, which calls for consideration of environmental effects of IBWC actions. We conducted vegetation and bird surveys within the Limitrophe and found that this river segment is unusually rich in native cottonwood and willow trees, marsh habitat, and resident and migratory birds compared to flow-regulated segments of river. A flood-frequency analysis showed that the existing levee system can easily contain a 100 year flood even if vegetation is not removed, and the existing braided channel system has greater carrying capacity than the proposed pilot channel.