我国黑土地农田土壤除草剂残留特征研究及展望

粮食安全是“国之大者”.东北黑土地作为我国重要的粮仓,是保障国家粮食安全的“压舱石”.但黑土地农田除草剂的长期高强度施用,导致除草剂在土壤中积累和迁移,影响土壤质量、作物产量和品质,阻碍黑土地可持续利用和农业可持续发展.解决黑土地农田除草剂残留问题,既要从源头管控除草剂的施用,也要掌握除草剂的残留特征、时空演变和驱动因素,才能做到科学防控、精准施策.系统总结了我国黑土地农田除草剂的施用状况和存在的问题,全面梳理了除草剂的残留现状,指出了当前在黑土地农田除草剂残留特征、空间分布和污染诊断等研究上的不足,提出了我国黑土地农田除草剂残留诊断与风险管理研究思路与重点方向,为保障我国黑土地农田土壤健康、粮食安全和生态系统安全提供科技支撑.     

Uncertainty Models for Estimates of Physical Characteristics of River Segments Over Large Areas

Spatially comprehensive estimates of the physical characteristics of river segments over large areas are required in many large‐scale analyses of river systems and for the management of multiple basins. Remote sensing and modeling are often used to estimate river characteristics over large areas, but the uncertainties associated with these estimates and their dependence on the physical characteristics of the segments and their catchments are seldom quantified. Using test data with varying degrees of independence, we derived analytical models of the uncertainty associated with estimates of upstream catchment area (CA), segment slope, and mean annual discharge for all river segments of a digital representation of the hydrographic network of France. Although there were strong relationships between our test data and estimates at the scale of France, there were also large relative local uncertainties, which varied with the physical characteristics of the segments and their catchments. Discharge and CA were relatively uncertain where discharge was low and catchments were small. Discharge uncertainty also increased in catchments with large rainfall events and low minimum temperature. The uncertainty of segment slope was strongly related to segment length. Our uncertainty models were consistent across large regions of France, suggesting some degree of generality. Their analytical formulation should facilitate their use in large‐scale ecological studies and simulation models.     

Economic valuation as a tool to support decision-making in strategic green infrastructure planning

Decision-making in spatial planning is often based only on administrative regulations and procedures. This approach does not guarantee an efficient allocation of scarce financial resources. Consequently, the present paper discusses the practical relevance of an approach to incorporate results of economic valuation into strategic spatial planning for the example of green infrastructure. For this, a contingent valuation was conducted at a reference site in Esslingen, Germany. Here, participants of the survey stated their willingness to pay for different green infrastructure investment categories. Build on the survey results, the possible future foci of regional green infrastructure planning are derived and impacts on regional green infrastructure policy for the case of the Neckar region are investigated.     

1996-2010年云南省旅游总收入差异的时空变化分析

选取1996-2010年云南省16个市州的旅游总收入为研究对象,综合运用标准差、变异系数、泰尔指数、累计比重等方法分析云南旅游总收入的总体差异,探讨近15年来全省旅游总收入在地带间、地带内和市州际的差异及其变动演进.研究表明,时间上云南省旅游总收入呈现绝对差异不断扩大但相对差异在小幅增长后逐步收敛的特征;空间上,云南省旅游总收入差异明显但不平衡特征正在逐步缩小.云南省旅游总收入的差异主要是由于地带间差异和地带内差异共同导致,地带间差异已有所缓和;滇西北、滇西南、滇东南和滇中地区是地带内差异的最重要来源;旅游资源禀赋、旅游基础设施、旅游发展政策和经济发展水平是云南省旅游总收入的时空差异及其变动的的主要原因.     

淮河流域新型城镇化水平的空间差异及其影响因素分析

以淮河流域31个地级市为研究对象,从人口、经济、生活和环境四个方面构建了新型城镇化水平的综合评价指标体系,利用熵值法对其综合城镇化水平及其子系统水平进行评价.结果表明,淮河流域地区新型城镇化发展水平存在较强的空间依赖性,即一个地区城镇化水平的提高通过空间溢出促进周边地区的城镇化发展,地区产业结构的变化是决定其新型城镇化水平的主要因素,尤其是第三产业发展对其影响极大.     

Pseudoreplication in Tropical Forests and the Resulting Effects on Biodiversity Conservation

Tropical forest ecosystems are threatened by habitat conversion and other anthropogenic actions. Timber production forests can augment the conservation value of primary forest reserves, but studies of logging effects often yield contradictory findings and thus inhibit efforts to develop clear conservation strategies. We hypothesized that much of this variability reflects a common methodological flaw, simple pseudoreplication, that confounds logging effects with preexisting spatial variation. We reviewed recent studies of the effects of logging on biodiversity in tropical forests (n = 77) and found that 68% were definitively pseudoreplicated while only 7% were definitively free of pseudoreplication. The remaining proportion could not be clearly categorized. In addition, we collected compositional data on 7 taxa in 24 primary forest research plots and systematically analyzed subsets of these plots to calculate the probability that a pseudoreplicated comparison would incorrectly identify a treatment effect. Rates of false inference (i.e., the spurious detection of a treatment effect) were >0.5 for 2 taxa, 0.3–0.5 for 2 taxa, and <0.3 for 3 taxa. Our findings demonstrate that tropical conservation strategies are being informed by a body of literature that is rife with unwarranted inferences. Addressing pseudoreplication is essential for accurately assessing biodiversity in logged forests, identifying the relative merits of specific management practices and landscape configurations, and effectively balancing conservation with timber production in tropical forests. Pseudoreplicación en Bosques Tropicales y Efectos Resultantes Sobre la Conservación de Biodiversidad     

Assessing the Risk of Ships Striking Large Whales in Marine Spatial Planning

Marine spatial planning provides a comprehensive framework for managing multiple uses of the marine environment and has the potential to minimize environmental impacts and reduce conflicts among users. Spatially explicit assessments of the risks to key marine species from human activities are a requirement of marine spatial planning. We assessed the risk of ships striking humpback (Megaptera novaeangliae), blue (Balaenoptera musculus), and fin (Balaenoptera physalus) whales in alternative shipping routes derived from patterns of shipping traffic off Southern California (U.S.A.). Specifically, we developed whale‐habitat models and assumed ship‐strike risk for the alternative shipping routes was proportional to the number of whales predicted by the models to occur within each route. This definition of risk assumes all ships travel within a single route. We also calculated risk assuming ships travel via multiple routes. We estimated the potential for conflict between shipping and other uses (military training and fishing) due to overlap with the routes. We also estimated the overlap between shipping routes and protected areas. The route with the lowest risk for humpback whales had the highest risk for fin whales and vice versa. Risk to both species may be ameliorated by creating a new route south of the northern Channel Islands and spreading traffic between this new route and the existing route in the Santa Barbara Channel. Creating a longer route may reduce the overlap between shipping and other uses by concentrating shipping traffic. Blue whales are distributed more evenly across our study area than humpback and fin whales; thus, risk could not be ameliorated by concentrating shipping traffic in any of the routes we considered. Reducing ship‐strike risk for blue whales may be necessary because our estimate of the potential number of strikes suggests that they are likely to exceed allowable levels of anthropogenic impacts established under U.S. laws. Evaluación del Riesgo de Colisiones de Barcos y Ballenas en la Planificación Marina Espacial     

Watershed management and the Web

Watershed analysis and watershed management are developing as tools of integrated ecological and economic study. They also assist decision-making at the regional scale. The new technology and thinking offered by the advent of the Internet and the World Wide Web is highly complementary to some of the goals of watershed analysis. Services delivered by the Web are open, interactive, fast, spatially distributed, hierarchical and flexible. The Web offers the ability to display information creatively, to interact with that information and to change and modify it remotely. In this way the Internet provides a much-needed opportunity to deliver scientific findings and information to stakeholders and to link stakeholders together providing for collective decision-making. The benefits fall into two major categories: methodological and educational. Methodologically the approach furthers the watershed management concept, offering an avenue for practical implementation of watershed management principles. For educational purposes the Web is a source of data and insight serving a variety of needs at all levels. We use the Patuxent River case study to illustrate the web-based approach to watershed management. A watershed scale simulation model is built for the Patuxent area and it serves as a core for watershed management design based on web applications. It integrates the knowledge available for the Patuxent area in a comprehensive and systematic format, and provides a conceptual basis for understanding the performance of the watershed as a system. Moreover, the extensive data collection and conceptualisation required within the framework of the modeling effort stimulates close contact with the environmental management community. This is further enhanced by offering access to the modeling results and the data sets over the Web. Additional web applications and links are provided to increase awareness and involvement of stakeholders in the watershed management process. We argue that it is not the amount and quality of information that is crucial for the success of watershed management, but how well the information is disseminated, shared and used by the stakeholders. In this respect the Web offers a wealth of opportunities for the decision-making process, but still to be answered are the questions at what scale and how widely will the Web be accepted as a management tool, and how can watershed management benefit from web applications.     

基于协调发展视角的区域发展差异研究

20世纪90年代以来，区域差异研究成为学术界和政府管理者关注的热点领域。长期以来学者们主要以单一经济指标或复合经济指标作为衡量因子，分析区域经济差异时空演变及差异背后的自然、社会、经济驱动机理。从可持续发展的角度看，区域发展不单是区域经济的发展，而应是社会、经济与资源环境三方面的协调。基于这一理解，从可持续协调发展入手，建立了区域发展综合评价指标体系，选取了表征社会进步、经济发展和资源环境支持3个方面的27个因素作为评价指标，分析了区域综合发展的测算方法，提出了综合发展指数和发展协调指数。在案例分析中运用所设计的测度方法对江苏省内县级行政单位的综合发展进行了评价和分析。     

Parameterization of Albedo over Heterogeneous Surfaces in Coupled Land-Atmosphere Schemes for Environmental Modeling. Part I: Theoretical Background

In grid-based environmental models, the underlying surface consists of patches of solid and liquid parts and different plant communities, creating a very heterogeneous picture in the grid cell. In these cases, numerical modelers usually use a simple arithmetic average to determine the grid-cell albedo, a key variable in the parameterization of the land-surface radiative transfer over the grid cell. The object of this paper is to consider the assumptions for aggregating the albedo over a very heterogeneous surface where various surfaces occur at different heights, and, then propose a method for deriving a general expression for it. The suggested expression for the albedo is compared with the conventional approach, for the two-patches grid-cell with a simple geometrical distribution and different heights of its components. A numerical test is performed to compare the two approaches by numerical simulation of the evolution of the surface temperature over the particular grid-cell. Specifically, a one-dimensional land-surface model was applied to an isolated rocky grid-cell with a hole in the center; the model was forced with meteorological observations taken on July 17, 1999 in Philadelphia, PA.