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1.
    
Sewage sludge, or biosolids, produced in wastewater treatment plants (WWTP) can be used as an alternative to organic fertilizer in the agricultural field. However, it holds a large amount of anthropogenic chemicals, such as drugs and metals. The aim of the present study is to evaluate biochemical biomarker responses in earthworms (Eisenia andrei) exposed to soil presenting different sludge concentrations deriving from the largest WWTP in Southern Brazil. Treatments comprised 3%, 6%, 12%, 24%, 50%, and 75% of sludge incorporated to native forest soil, 100% of sludge and the control group (0%). Concentrations of different drugs, mainly of antibiotics, as well as high sulfur, magnesium, potassium, zinc, and phosphorus were identified in analyzed sewage sludge. Exposed earthworms were collected on the 7th, 14th, and 28th day of the experiment and subjected to analysis of lipid peroxidation levels (TBARS), acetylcholinesterase (AChE), catalase (CAT), and glutathione S-transferase (GST) activity. Treatments with 50%, 75%, and 100% of sludge were lethal to earthworms after 7 days. Based on biochemical tests performed in treatments with 3%, 6%, 12%, and 24% of sludge, the highest sludge concentrations (12% and 24%) and the longest exposure time (28 days) led to significant changes in biomarkers. Therefore, sewage sludge must be incorporated into the soil at concentrations lower than 3%, mainly due to changes in CAT, AChE, GST, and the resulting lipid damage observed at concentrations of 6%, 12%, and 24%.  相似文献   
2.
The Countryside and Rights of Way Act 2000 places a duty on highways and national park authorities to establish local access forums (LAFs), to advise on the improvement of public access to land for the purposes of open air recreation and enjoyment. This paper examines these proposals in the context of recent academic and political debates about deliberative democracy, and empirical research on the nature and practice of existing access liaison groups and forums. While demonstrating that the proposed LAFs are consistent with contemporary constructs of participative, if not deliberative democracy, the paper argues that most existing groups and forums fall short of this ideal, in a number of significant respects. The paper proceeds to discuss the extent to which the draft regulations for LAFs in England and Wales address these issues, and concludes by questioning the extent to which such consultative arrangements can contribute to new forms of local governance.  相似文献   
3.
Phosphorus transfer in runoff from intensive pasture systems has been extensively researched at a range of scales. However, integration of data from the range of scales has been limited. This paper presents a conceptual model of P transfer that incorporates landscape effects and reviews the research relating to P transfer at a range of scales in light of this model. The contribution of inorganic P sources to P transfer is relatively well understood, but the contribution of organic P to P transfer is still relatively poorly defined. Phosphorus transfer has been studied at laboratory, profile, plot, field, and watershed scales. The majority of research investigating the processes of P transfer (as distinct from merely quantifying P transfer) has been undertaken at the plot scale. However, there is a growing need to integrate data gathered at a range of scales so that more effective strategies to reduce P transfer can be identified. This has been hindered by the lack of a clear conceptual framework to describe differences in the processes of P transfer at the various scales. The interaction of hydrological (transport) factors with P source factors, and their relationship to scale, require further examination. Runoff-generating areas are highly variable, both temporally and spatially. Improvement in the understanding and identification of these areas will contribute to increased effectiveness of strategies aimed at reducing P transfers in runoff. A thorough consideration of scale effects using the conceptual model of P transfer outlined in this paper will facilitate the development of improved strategies for reducing P losses in runoff.  相似文献   
4.
    
Work on the post-2020 global biodiversity framework is now well advanced and will outline a vision, goals, and targets for the next decade of biodiversity conservation and beyond. For the effectiveness of Protected areas and Other Effective area-based Conservation Measures, an indicator has been proposed for “areas meeting their documented ecological objectives.” However, the Convention on Biological Diversity (CBD) has not identified or agreed on what data should inform this indicator. Here we draw on experiences from the assessment of protected area effectiveness in the CBD's previous strategic plan to provide recommendations on the essential elements related to biodiversity outcomes and management that need to be captured in this updated indicator as well as how this could be done. Our proposed protected area effectiveness indicators include a combination of remotely derived products for all protected areas, combined with data from monitoring of both protected area management and trends in species and ecosystems based on field observations. Additionally, we highlight the need for creating a digital infrastructure to operationalize national-level data-capture. We believe these steps are critical and urge the adoption of suitable protected area effectiveness indicators before the post-2020 framework is agreed in 2021.  相似文献   
5.
Forest networks     
Summary A study beyond the political boundaries in planning strategies for long-term management of the global forest estate is presented. Three alternative forest networks are proposed: (1) the genetic-evolutionary network, based around common evolutionary features, thus delineating similar forest types where conservation and management issues are likely to be compatible; (2) the current ecological and environmental network, based around the role that forests play in the wider ecosystem, including regular and irregular migration pathways, networks to absorb the impact of climate change, water filters etc; (3) the human impact network, based on the history of human involvement in the forest and its implications. The practical policy significance of the various networks is discussed in turn.This paper was researched as part of a project carried out for the World Wide Fund for Nature (WWF). Nigel Dudley is an ecologist, based in the UK, with 15 years experience as a consultant for NGOs, local government and international organizations. He is a former director of the Soil Association and now works with Equilibrium Consultants at the above address. For the past five years he has worked closely with WWF on forest conservation projects and has written several reports for the organization, includingForests in trouble: a review of the status of temperate forests worldwide.  相似文献   
6.
It is widely accepted that wetland ecosystems are under threat worldwide. Many communities are now trying to establish wetland rehabilitation programs, but are confounded by a lack of objective information on wetland condition or significance. In this study, a multi-criteria decision-making method, TOPSIS (the Technique for Order Preference by Similarity to Ideal Solution), was adapted to assist in the role of assessing wetland condition and rehabilitation priority in the Clarence River Catchment (New South Wales, Australia). Using 13 GIS data layers that described wetland character, wetland protection, and wetland threats, the wetlands were ranked in terms of condition. Through manipulation of the original model, the wetlands were prioritized for rehabilitation. The method offered a screening tool for the managers in choosing potential candidate wetlands for rehabilitation in a region.  相似文献   
7.
Nigel Roxburgh   《Resources Policy》1979,5(4):260-272
Inadequacies in the knowledge base seriously hamper discussion of the resource problem. Following a mercury-centered explanation of the problems of estimates, resource limits and of calculation of figures for different categories of resources and reserves, the article attempts to clarify the roles that theoretical and empirical knowledge have in structuring the options within the resource system.  相似文献   
8.
A systems approach was used to evaluate environmental loading of Cryptosporidium oocysts on five coastal dairies in California. One aspect of the study was to determine Cryptosporidium oocyst concentrations and loads for 350 storm runoff samples from dairy high use areas collected over two storm seasons. Selected farm factors and beneficial management practices (BMPs) associated with reducing the Cryptosporidium load in storm runoff were assessed. Using immunomagnetic separation (IMS) with direct fluorescent antibody (DFA) analysis, Cryptosporidium oocysts were detected on four of the five farms and in 21% of storm runoff samples overall. Oocysts were detected in 59% of runoff samples collected near cattle less than 2 mo old, while 10% of runoff samples collected near cattle over 6 mo old were positive. Factors associated with environmental loading of Cryptosporidium oocysts included cattle age class, 24 h precipitation, and cumulative seasonal precipitation, but not percent slope, lot acreage, cattle stocking number, or cattle density. Vegetated buffer strips and straw mulch application significantly reduced the protozoal concentrations and loads in storm runoff, while cattle exclusion and removal of manure did not. The study findings suggest that BMPs such as vegetated buffer strips and straw mulch application, especially when placed near calf areas, will reduce environmental loading of fecal protozoa and improve stormwater quality. These findings are assisting working dairies in their efforts to improve farm and ecosystem health along the California coast.  相似文献   
9.
    
The servicising approach in vineyard protection is considered a valid alternative to achieve decoupling between the economic and environmental performance of viticulture. In this paper, a policy package is designed to promote the uptake of a servicised model of vineyard protection in an area of smallholding viticulture. In doing so, a specific methodology based on a step by step protocol has been followed that aims to come up with a package that is effective, implementable and socially as well as politically acceptable. The paper concludes on the importance of combining several policy instruments in a policy package to realise the political objective. The proposed viable policy package includes incentives that support the companies’ shift towards offering crop protection solutions, further development of IPM solutions and instruments that encourage farmers to reduce the use of pesticides and collectively hire crop protection services.  相似文献   
10.
    
Systematic conservation planning and Key Biodiversity Areas (KBAs) are the two most widely used approaches for identifying important sites for biodiversity. However, there is limited advice for conservation policy makers and practitioners on when and how they should be combined. Here we provide such guidance, using insights from the recently developed Global Standard for the Identification of KBAs and the language of decision science to review and clarify their similarities and differences. We argue the two approaches are broadly similar, with both setting transparent environmental objectives and specifying actions. There is however greater contrast in the data used and actions involved, as the KBA approach uses biodiversity data alone and identifies sites for monitoring and vigilance actions at a minimum, whereas systematic conservation planning combines biodiversity and implementation-relevant data to guide management actions. This difference means there is much scope for combining approaches, so conservation planners should use KBA data in their analyses, setting context-specific targets for each KBA type, and planners and donors should use systematic conservation planning techniques when prioritizing between KBAs for management action. In doing so, they will benefit conservation policy, practice and research by building on the collaborations formed through the KBA Standard's development.  相似文献   
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