Soil conservation policy measures to control wind erosion in northwestern Europe

Wind erosion is not as significant or a widespread problem in Europe as in dryer parts of the world, but it can cause major damage in small areas. The hazard is greatest in the lowlands of northwestern Europe with more than 3 million ha at high-potential wind erosion risk. Crop damage and off-site damage have prompted farmers and policymakers to pay more attention to wind erosion control. A great variety of measures have been developed in the last decades. Most farmers, however, only use measures to protect their high value crops. In existing policies, little attention is paid to the off-site effects and long-term effects of wind erosion. There are no direct policy measures at a European level to control soil erosion, and few measures exist in individual Member States. Agricultural or environmental EC policies offer different policy tools to approach the wind erosion problems related to agricultural practices. Tools like subsidies for the re-afforestation of arable land can help regional policy makers with the implementation of wind erosion control measures. A case study concerning the ‘Code of Good Agricultural Practice’ shows that regional differences result in different control measures that fits best given the physical, social and economic context. The formulation of the practical details of such code should therefore remain a task of the local or regional government. The main objectives of a Code of Good Agricultural Practice could be formulated at national or European level.     

Do conservation managers use scientific evidence to support their decision-making?

Conservation involves making decisions on appropriate action from a wide range of options. For conservation to be effective, decision-makers need to know what actions do and do not work. Ideally, decisions should be based on effectiveness as demonstrated by scientific experiment or systematic review of evidence. Can decision-makers get this kind of information? We undertook a formal assessment of the extent to which scientific evidence is being used in conservation practice by conducting a survey of management plans and their compilers from major conservation organizations within the UK. Data collected suggest that the majority of conservation actions remain experience-based and rely heavily on traditional land management practices because, many management interventions remain unevaluated and, although some evidence exists, much is not readily accessible in a suitable form. We argue that nature conservation along with other fields of applied ecology, should exploit the concept of evidence-based practice developed and used in medicine and public health that aims to provide the best available evidence to the decision-maker(s) on the likely outcomes of alternative actions. Through critical evaluation, we present the challenges and benefits of adopting evidence based practice from the decision-makers point of view and identify the process to be followed to make it work.     

Interactions between poaching and management policy affect marine reserves as conservation tools

To explore the effects of poaching within marine reserve boundaries under three different management policies this analysis uses a simple age-structured reserve model based on yield maximization or reproductive thresholds of Black rockfish (Sebastes melanops). Departures from the traditional assumptions of full compliance to reserve boundaries alter the conclusions of prior modeling work that demonstrate yield equivalence to no-reserve effort control management and augmented reproductive benefits when small reserves are implemented. By degrading the recruitment subsidization effect to nonreserve areas from protected reserve populations, poaching resulted in negative externalities for compliant fishermen in open areas in terms of yield and degraded the reproductive output and age-structure of the system. All three policies required effort reduction in open areas as a response to poaching in reserves. The strength of the impacts from poaching varied with policy choice and harvest intensity in the reserve, where at the highest level of poaching modeled here (15% annual exploitation rate of the vulnerable reserve population) biological and fishery benefits of implementing reserves were totally negated. Under the assumptions of this model, a policy managing for a reproductive threshold that excludes the reserve population is the precautionary choice if poaching is likely. The results of this exercise emphasize the importance of garnering compliance to reserve boundaries from resource-users for spatial closures to be successful ocean management tools.     

Estimating organic carbon in the soils of Europe for policy support

The estimation of soil carbon content is of pressing concern for soil protection and in mitigation strategies for global warming. This paper describes the methodology developed and the results obtained in a study aimed at estimating organic carbon contents (%) in topsoils across Europe. The information presented in map form provides policy-makers with estimates of current topsoil organic carbon contents for developing strategies for soil protection at regional level. Such baseline data are also of importance in global change modelling and may be used to estimate regional differences in soil organic carbon (SOC) stocks and projected changes therein, as required for example under the Kyoto Protocol to the United Nations Framework Convention on Climate Change, after having taken into account regional differences in bulk density. The study uses a novel approach combining a rule-based system with detailed thematic spatial data layers to arrive at a much-improved result over either method, using advanced methods for spatial data processing. The rule-based system is provided by the pedo-transfer rules, which were developed for use with the European Soil Database. The strong effects of vegetation and land use on SOC have been taken into account in the calculations, and the influence of temperature on organic carbon contents has been considered in the form of a heuristic function. Processing of all thematic data was performed on harmonized spatial data layers in raster format with a 1 km × 1 km grid spacing. This resolution is regarded as appropriate for planning effective soil protection measures at the European level. The approach is thought to be transferable to other regions of the world that are facing similar questions, provided adequate data are available for these regions. However, there will always be an element of uncertainty in estimating or determining the spatial distribution of organic carbon contents of soils.     

A decision support system for soil and water conservation measures on agricultural watersheds

Integrated watershed management (IWM) is vital in achieving agricultural sustainability in terms of both production and environmental protection. A decision support system (DSS) is useful in generating alternative decision scenarios for management of natural resources, facilitating the implementation of IWM concepts in an interactive and holistic way. The decision to implement an appropriate land use coupled with suitable soil and water conservation techniques not only enhances watershed health but also prevents sediment losses. Besides reducing basin fertility, such losses decrease the storage capacity of downstream reservoirs through silt deposition, which can, in turn, give rise to low biomass production and poorer flood control. In order to facilitate IWM, an effort was made to develop, in the Visual Basic programming language, a soil and water conservation DSS which considered both structural and cropping practices for arresting sediment loss. Input parameters to the DSS for a given tract of land included: mean slope; sediment loss; soil type; and land capability class (LCC). Outputs included decision criteria to choose among alternative structural measures and suggested cropping systems to serve as biological measures to reduce soil loss and conserve water. Structural watershed management measures included a variety of soil and water conservation structures widely adopted by farming communities throughout the world. The DSS is capable of providing sediment control solutions not only for small watersheds but also for larger drainage basins, by dividing the basin into smaller watersheds. The DSS was validated for a watershed on the Caribbean island of St Lucia and used to suggest measures for a 10° slope under specific soil type, sediment loss and LCC conditions. The measures proposed included bench terraces, graded contour bunds, conservation ditches, concrete chute spillways, diversion dams and conservation cropping systems. The measures actually adopted on‐site were conservation ditches, graded contour bunds and conservation cropping systems, a close parallel to the DSS's proposed measures. On slopes ranging from 5–55°, implementation of the suggested control measures resulted in a 34–37 per cent reduction in soil loss on the watershed. Copyright © 2004 John Wiley & Sons, Ltd.     

A gap analysis of terrestrial protected areas in England and its implications for conservation policy

Many protected area (PA) systems have developed in response to socio-economic and aesthetic criteria and need to be modified to increase their conservation value. National gap analyses are an important step in describing and addressing this problem, so we sought to determine the representativeness of English PAs devoted to biodiversity conservation by using Natural Areas (NAs), elevation and PA boundary data. We found that National Nature Reserves (NNRs) and Sites of Special Scientific Interests (SSSIs) cover only 6.3% of England and are generally small, with respective median areas of 1.1 and 0.2 km². The English PA system under-represents lowland areas and provides a median level of 2.5% protection for the NA types, with seventy nine per cent of NA types having less than 10% protection. Therefore, we suggest that England's PA system needs to be expanded, although this would probably entail modification of existing legislation to increase involvement by landowners. We also compare our results with previous appraisals that used species distribution record data and suggest that landscape-level analyses may give a more accurate and less positive assessment.     

Global analysis of cover management and support practice factors that control soil erosion and conservation

Cover management and support practices largely control the magnitude and variability of soil erosion. Although soil erosion models account for their importance (particularly by C- and P-factors in the Revised Universal Soil Loss Equation), obtaining spatially explicit quantitative field data on these factors remains challenging. Hence, also our insight into the effects of soil conservation measures at larger spatial scales remains limited. We analyzed the variation in C- and P-factors caused by human activities and climatic variables by reviewing 255 published articles reporting measured or calculated C- and P-factor values. We found a wide variation in both factor values across climatic zones, land use or cover types, and support practices. The average C-factor values decreased from arid (0.26) to humid (0.15) climates, whereas the average P-factor values increased (from 0.33 to 0.47, respectively). Thus, support practices reduce soil loss more effectively in drylands and drought-prone areas. The global average C-factor varies by one order of magnitude from cropland (0.34) to forest (0.03). Among the major crops, the average C-factor was highest for maize (0.42) followed by potato (0.40), among the major orchard crops, it was highest for olive (0.31), followed by vineyards (0.26). The P-factor ranged from 0.62 for contouring in cropland plots to 0.19 for trenches in uncultivated land. The C-factor results indicate that cultivated lands requiring intensive site preparation and weeding are most vulnerable to soil loss by sheet and rill erosion. The low P-factor for trenches, reduced tillage cultivation, and terraces suggests that significantly decreased soil loss is possible by implementing more efficient management practices. These results improve our understanding of the variation in C- and P-factors and support large-scale integrated catchment management interventions by applying soil erosion models where it is difficult to empirically determine the impact of particular land use or cover types and support practices: the datasets compiled in this study can support further modeling and land management attempts in different countries and geographic regions.     

欧美国家农业支持政策的调整与改革及其启示

由于农业的弱质性以及在国民经济中的重要地位，世界各国特别是经济发达国家越来越多地对农业采取了支持和保护措施。欧美国家已形成了农业支持政策体系，各种措施覆盖广泛，相互配套，共同发挥作用。归纳、总结和分析欧美国家农业支持政策的调整与改革及其成功经验，为建立健全我国农业政策体系提供有益的参考，以促进我国农业经济和农村社会的持续发展。     

Fifty years progress in soil physics

Despite a lengthy period of non-progress, soil physics has, over the last half-century, gained enormously in its self-confidence, its intellectual power, and its relevance to the practical problems of the real world.     

水土保持与生态文明

建设生态文明,其核心是确立人与自然和谐、平等、共存共荣的关系,其实质是要建设以资源环境承载力为基础、以自然规律为准则、以可持续发展为目标的资源节约型、环境友好型社会。我国1/3以上的国土面积存在水土流失问题,所以应该说水土保持是可持续发展的重要内容,是生态环境建设的重要组成部分,因而也就理所当然地应该担负起建设生态文明的历史重任。当前乃至长远,全社会都应始终不渝的坚持水土保持这一基本国策,从认识上、政策上、措施上、行动上高度重视和落实水土保持工作,只有实现山川秀美,才能保障生态文明建设的健康发展。     

Why be wasteful when preserving a valuable resource? A review article on the cost-effectiveness of European biodiversity conservation policy

Issues related to the cost-effectiveness of biodiversity conservation policies have not yet been prominent in European conservation research and policy-making. Nevertheless, there is a small but growing literature which analyses such issues. The article reviews this literature, and focuses on reserves and compensation payments for conservation measures as the two most relevant conservation policy instruments in Europe. Understanding of the cost-effective allocation of conservation measures and reserve sites has improved, and further light will be shed by integrating knowledge from ecology and the economic analysis of policy instruments. Although research on cost-effective monitoring, enforcement and decision-making has addressed certain issues, others very relevant to conservation policy such as implementation problems related to NATURA 2000 have been neglected.     

完善政策创新机制加快水土保持生态大示范区建设步伐

如何使以小流域为单元的水土流失综合治理转移到大流域、大示范区水土保持生态环境建设上来,自20世纪80年代以来,山西省进行了大量的尝试,以机制创新为动力,不断完善政策,创新治理组织形式和运行管理机制,取得了明显成效,加快了水土保持生态环境建设步伐。     

Are review articles a reliable source of evidence to support conservation and environmental management? A comparison with medicine

Review articles are important sources of information and often the only source of evidence used by decision makers in conservation and environmental management to assess effectiveness and impact of interventions and other actions. Recent developments in the field of medicine and public health have established ‘systematic review’ guidelines to minimise bias and explicitly document methodology, allowing replication and updating in light of further advances. The aim of this article was to assess the methodological and reporting rigour of reviews from the disciplines of conservation, ecology and environmental management (referred to as “ecological reviews”). This was achieved by comparing them to medical systematic reviews, using 27 detailed criteria well established in medicine. When compared with medical systematic reviews, ecological reviews were more likely to be prone to bias, lacking details in the methods used to search for studies, and were less likely to assess the relevance of studies, quality of the original experiments and to quantitatively synthesise the evidence. Overall, ecological reviews show lower quality and greater variation in reporting style and review methods. To address this, reviewers could use a systematic review approach and journals could provide more explicit guidelines for the preparation and production of review articles.     

The importance of understanding trade when designing effective conservation policy - The case of the vulnerable Abies guatemalensis Rehder

Trade may be an important factor driving over-exploitation of endangered species. Often, however, there are fundamental gaps in our knowledge of such trade: how are market chains structured and how do they operate? What drives demand? This paper investigates trade in Abies guatemalensis Rehder, a conifer species on CITES Appendix 1 and listed as vulnerable in the IUCN Red List of Threatened Species. The aim is to contribute to the development of an effective conservation policy in Guatemala. Data were collected from December 2004 to August 2007 through a nation-wide survey using standardised open-ended interviews with plantation owners (n = 26), retailers (n = 67) and urban consumers (n = 993). Triangulations of estimated traded amounts and prices, combined with an assessment of own-reported values, indicate that the findings were reliable. Illegally wild harvested branches move from collectors to regional and local wholesalers and finally to urban based retailers who assemble the branches on a pole (hereafter semi-natural trees). This is in parallel to legal trade in certified trees from plantations. The number of traded illegal semi-natural A. guatemalensis and plastic Christmas trees increased dramatically during 2002-2005; demand for other types of Christmas trees remained at low levels. In the same period, prices significantly increased for semi-natural A. guatemalensis trees but remained constant or fell for other Christmas trees. This is explained by rising per capita incomes, a strong cultural preference for the uniquely scented A. guatemalensis, significantly higher price of certified legal plantation trees and ineffective implementation of existent legislation. The importance of increasing legal supplies, e.g. through decreasing plantation production costs and involving local communities in managing in-situ resources, is emphasised.