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81.
Previous work has identified two patterns of arthropod recovery after insecticide applications to arable crops: dispersal-mediated recolonisation from untreated areas (Type A) and recolonisation within treated areas assisted by reduced predation (Type B). In this study, connectivity between field-edge habitats was manipulated using barriers to investigate whether a crop edge and adjacent hedgerow influence recolonisation of an insecticide-treated crop by surface-active Collembola and other arthropods. Collembola recovery patterns differed among closely-related taxa. Epigeic collembolan and macroarthropod communities were more diverse and abundant, and rates of artificial prey predation were higher, in sprayed crop areas connected to both hedgerow and unsprayed crop edge than in sprayed areas connected to the unsprayed edge alone. These findings indicate that effectiveness of unsprayed crop edges as sources of field recolonisation may depend on adjoining field margin habitats. An assumption in risk assessment that unsprayed crop edges assist population recovery within treated areas is not supported.  相似文献   
82.
On 25 April 1998, a breach of the tailings dam of the Los Frailes pyrite mine in southwestern Spain resulted in the release of 6 million m3 of acidic water and toxic sludge high in heavy metals. Contaminated material extended 40 km downstream, affecting agricultural land and parts of the wildlife-rich Do?ana Natural and National Parks, including the Entremuros, a very important area for birds. We report on the concentrations, distributions and bioavailability of zinc and cadmium in soil and vegetation from the Entremuros in November 1998 and October 1999, following 2 'cleanup' operations. Levels of Zn and Cd in soil increased significantly over this period, although this was not reflected consistently in metal concentrations in emergent macrophytes. We recommend monitoring of further cleanup attempts in order to develop means of minimizing potential impacts to wildlife in the area.  相似文献   
83.
A prototype web-based spatial information management tool (called eFarmer) was tested for its useability and usefulness by 46 Land Managers and 5 extension staff in Victoria, Australia. Participants had a range of enterprises (dairy, beef/sheep grazing, cropping, lifestyle land use), property sizes and computer ownership and expertise. A follow up study was conducted with 12 dairy farmers, where features regarding assessment of nutrient losses from paddocks (Farm Nutrient Loss Index, FNLI) were added to eFarmer. Over 27,000 maps (including 11,000 with aerial photography) were accessed by Land Managers during a 5-month trial period. Despite limited training and support, 1350 people are registered users, and approximately 700 have actively used the tool. Reasons for the success include providing improved access to spatial information, enabling measurement of farm features and creation of farm maps, providing a basis for decision-making about farm inputs, support for better farm and landscape scale action planning and production and Land Managers being able to seek management advice from the extension staff who facilitated eFarmer testing programs. For dairy farmers in the FNLI trial, awareness of off-site impacts increased and most changed management practices. Provision of on-going training and support will be at least as important as further development of the tool itself. Web-based spatial information tools have potential to improve the awareness of Land Managers about their environmental impacts and influence their decision-making. Access to spatial information has potential to reduce information asymmetry between Land Managers, extension staff and catchment planners in a constructive way. It will also change the role of extension staff away from being an expert with answers, to a facilitator enabling learning. Results have applicability in countries where there is a high level of farm computer ownership, relevant spatial information is available in GIS format, where governments are happy to make spatial information available to the public and there is pressure for increased environmental awareness and improved decision making by Land Managers.  相似文献   
84.
Local 'Barriers' to Environmentally Sustainable Transport Planning   总被引:1,自引:0,他引:1  
Rapid changes are occurring in the rhetoric and practice of transport planning in the UK. Driven by ever increasing road congestion and growing awareness of the impact of road transport on the environment, a consensus is said to be emerging over the implementation of a new approach to UK transport planning centred on managing the demand for road travel rather than catering for it. This paper explores the depth and breadth of the penetration of this new consensus in relation to policy making in central government and in three local case-study areas. The paper charts the factors that have shifted transport policy direction and are contributing to and inhibiting the adoption of a new demand management approach. It concludes by stating that whilst definitive shifts in transport-planning rhetoric and practice have occurred in recent times, shifts toward demand management have been slow due in particular to local cultural and political difficulties. These persist in many localities and in similar policy areas and an awareness of these is useful in highlighting difficulties in the adoption of environmental sustainability agendas in other policy fields.  相似文献   
85.
生态博物馆理念及其在少数民族社区景观保护中的作用   总被引:13,自引:0,他引:13  
生态博物馆是兴起于20世纪70年代的一种创新的文化景观保护与展示方式。其基本理念是以生态学为基础,以特定地域某一特定群体的全部文化内涵为展示内容。与传统博物馆相比,其最明显的创新在于,它以社区为基础,以就地保护的方式进行原生态状况下的“活态文化遗产”的保护和展示。中挪合作项目贵州梭嘎生态博物馆是中国和亚洲第一座生态博物馆,是以“长角苗”民族文化景观为特征,由12个相连的苗族山区村寨组成。馆区自开放以来已接待了大量的参观游览者,在充分发挥其良好的社会展示功能的同时,也获得了较好的经济效益。从梭嘎生态博物馆的建设与运行中,也发现了一些值得进一步探讨的问题,如展示与保护内容的界定问题、文化保护与旅游发展的关系处理问题、区内接待规模与环境容量的测定问题,等等。  相似文献   
86.

Problem

Falling is a leading cause of serious injury, loss of independence, and nursing-home admission in older adults. Impaired balance control is a major contributing factor.

Methods

Results from our balance-control studies have been applied in the development of new and improved interventions and assessment tools. Initiatives to facilitate knowledge-translation of this work include setting up a new network of balance clinics, a research-user network and a research-user advisory board.

Results

Our findings support the efficacy of the developed balance-training methods, balance-enhancing footwear, neuro-prosthesis, walker design, handrail-cueing system, and handrail-design recommendations in improving specific aspects of balance control.

Impact on Knowledge Users

A new balance-assessment tool has been implemented in the first new balance clinic, a new balance-enhancing insole is available through pharmacies and other commercial outlets, and handrail design recommendations have been incorporated into 10 Canadian and American building codes. Work in progress is expected to have further impact.  相似文献   
87.
Impact of consistent boundary layer mixing approaches between NAM and CMAQ   总被引:1,自引:0,他引:1  
Discrepancies in grid structure, dynamics and physics packages in the offline coupled NWS/NCEP NAM meteorological model with the U.S. Environmental Protection Agency Community Multiscale Air Quality (CMAQ) model can give rise to inconsistencies. This study investigates the use of three vertical mixing schemes to drive chemistry tracers in the National Air Quality Forecast Capability (NAQFC). The three schemes evaluated in this study represent various degrees of coupling to improve the commonality in turbulence parameterization between the meteorological and chemistry models. The methods tested include: (1) using NAM predicted TKE-based planetary boundary height, h, as the prime parameter to derive CMAQ vertical diffusivity; (2) using the NAM mixed layer depth to determine h and then proceeding as in (1); and (3) using NAM predicted vertical diffusivity directly to parameterize turbulence mixing within CMAQ. A two week period with elevated surface O3 concentrations during the summer 2006 has been selected to test these schemes in a sensitivity study. The study results are verified and evaluated using the EPA AIRNow monitoring network and other ozonesonde data. The third method is preferred a priori as it represents the tightest coupling option studied in this work for turbulent mixing processes between the meteorological and air quality models. It was found to accurately reproduce the upper bounds of turbulent mixing and provide the best agreement between predicted h and ozonesonde observed relative humidity profile inferred h for sites investigated in this study. However, this did not translate into the best agreement in surface O3 concentrations. Overall verification results during the test period of two weeks in August 2006, did not show superiority of this method over the other 2 methods in all regions of the continental U.S. Further efforts in model improvement for the parameterizations of turbulent mixing and other surface O3 forecast related processes are warranted.  相似文献   
88.
89.
    
Fragmentation of the boreal forest by linear features, including seismic lines, has destabilized predator–prey dynamics, resulting in the decline of woodland caribou (Rangifer tarandus caribou) populations. Restoration of human-altered habitat has therefore been identified as a critical management tool for achieving self-sustaining woodland caribou populations. However, only recently has testing of the response of caribou and other wildlife to restoration activities been conducted. Early work has centered around assessing changes in wildlife use of restored seismic lines. We evaluated whether restoration reduces the movement rates of predators and their associated prey, which is expected to decrease predator hunting efficiency and ultimately reduce caribou mortality. We developed a new method for using cameras to measure fine-scale movement by measuring speed as animals traveled between cameras in an array. We used our method to quantify speed of caribou, moose (Alces alces), bears (Ursus americanus), and wolves (Canis lupus) on treated (restored) and untreated seismic lines. Restoration treatments reduced travel speeds along seismic lines of wolves by 1.38 km/h, bears by 0.55 km/h, and caribou by 1.57 km/h, but did not reduce moose travel speeds. Reduced predator and caribou speeds on treated seismic lines are predicted to decrease encounter rates between predators and caribou and thus lower caribou kill rates. However, further work is needed to determine whether reduced movement rates result in reduced encounter rates with prey, and ultimately reduced caribou mortality.  相似文献   
90.
Farm forestry is a very minor land use in the inland agricultural landscapes of Australia. The Australian Government intends to introduce a program to encourage landholders to trade the carbon sequestration value of plantations and this may change the relative profitability of plantations against other agricultural land uses. This research compares the returns from a timber and ‘carbon’ plantation, with those from grazing and a common crop rotation in the Kingaroy area of Queensland.Typical production patterns for all systems were developed from producer and expert knowledge and soil and vegetation sampling were used to estimate sequestration rates. The costs and benefits of all land use systems were converted into monetary terms and discounted to produce net present values. With a standard discount rate and average commodity prices based on recent history, cultivation is the most profitable option, followed by pasture and plantations. After the inclusion of carbon, plantations are the most profitable option, followed by pasture and cultivation. A number of qualifications of these findings are also discussed.  相似文献   
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