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761.
Seasoned conservation researchers often struggle to bridge the research–implementation gap and promote the translation of their work into meaningful conservation actions. Graduate students face the same problems and must contend with obstacles such as limited opportunities for relevant interdisciplinary training and a lack of institutional support for application of research results. However, students also have a crucial set of opportunities (e.g., access to academic resources outside their degree programs and opportunities to design research projects promoting collaboration with stakeholders) at their disposal to address these problems. On the basis of results of breakout discussions at a symposium on the human dimensions of the ocean, a review of the literature, and our own experiences, we devised recommendations on how graduate students can create resources within their academic institutions, institutionalize resources, and engage with stakeholders to promote real‐world conservation outcomes. Within their academic institutions, graduate students should foster links to practitioners and promote knowledge and skill sharing among students. To institutionalize resources, students should cultivate student leaders and faculty sponsors, systematically document their program activities, and engage in strategic planning to promote the sustainability of their efforts. While conducting research, students should create connections to and engage actively with stakeholders in their relevant study areas and disseminate research results both to stakeholders and the broader public. Our recommendations can serve as a template for graduate students wishing to bridge the research–implementation gap, both during their current studies and in their future careers as conservation researchers and practitioners. Recomendaciones Prácticas para Ayudar a Estudiantes a Vencer la Brecha entre Investigación e Implementación y Promover la Conservación  相似文献   
762.
763.
Recently there has been considerable concern about declines in bee communities in agricultural and natural habitats. The value of pollination to agriculture, provided primarily by bees, is >$200 billion/year worldwide, and in natural ecosystems it is thought to be even greater. However, no monitoring program exists to accurately detect declines in abundance of insect pollinators; thus, it is difficult to quantify the status of bee communities or estimate the extent of declines. We used data from 11 multiyear studies of bee communities to devise a program to monitor pollinators at regional, national, or international scales. In these studies, 7 different methods for sampling bees were used and bees were sampled on 3 different continents. We estimated that a monitoring program with 200–250 sampling locations each sampled twice over 5 years would provide sufficient power to detect small (2–5%) annual declines in the number of species and in total abundance and would cost U.S.$2,000,000. To detect declines as small as 1% annually over the same period would require >300 sampling locations. Given the role of pollinators in food security and ecosystem function, we recommend establishment of integrated regional and international monitoring programs to detect changes in pollinator communities. Detección de Declinaciones de Insectos Polinizadores a Escalas Regional y Global  相似文献   
764.
There is a lack of quantitative information on the effectiveness of selective‐logging practices in ameliorating effects of logging on faunal communities. We conducted a large‐scale replicated field study in 3 selectively logged moist semideciduous forests in West Africa at varying times after timber extraction to assess post logging effects on amphibian assemblages. Specifically, we assessed whether the diversity, abundance, and assemblage composition of amphibians changed over time for forest‐dependent species and those tolerant of forest disturbance. In 2009, we sampled amphibians in 3 forests (total of 48 study plots, each 2 ha) in southwestern Ghana. In each forest, we established plots in undisturbed forest, recently logged forest, and forest logged 10 and 20 years previously. Logging intensity was constant across sites with 3 trees/ha removed. Recently logged forests supported substantially more species than unlogged forests. This was due to an influx of disturbance‐tolerant species after logging. Simultaneously Simpson's index decreased, with increased in dominance of a few species. As time since logging increased richness of disturbance‐tolerant species decreased until 10 years after logging when their composition was indistinguishable from unlogged forests. Simpson's index increased with time since logging and was indistinguishable from unlogged forest 20 years after logging. Forest specialists decreased after logging and recovered slowly. However, after 20 years amphibian assemblages had returned to a state indistinguishable from that of undisturbed forest in both abundance and composition. These results demonstrate that even with low‐intensity logging (≤3 trees/ha) a minimum 20‐year rotation of logging is required for effective conservation of amphibian assemblages in moist semideciduous forests. Furthermore, remnant patches of intact forests retained in the landscape and the presence of permanent brooks may aid in the effective recovery of amphibian assemblages. Recuperación de Ensambles de Anfibios en Dos Etapas Después de la Tala Selectiva de Bosques Tropicales  相似文献   
765.
Abstract

A greenhouse experiment was conducted under simulated field conditions using large‐capacity plastic pots, filled each one with 25 kg of air‐dried calcareous soil. Besides the control, four treatments were prepared by applying separately two rates (20 and 80 Mg ha‐1) of municipal solid waste (MSW) compost, and co‐composted municipal solid waste and sewage sludge (MSW‐SS). Lettuce was planted and harvested 2.5 months later. The application of composted urban wastes tended to increase Cu concentration in lettuce with respect to the control, but it was only significant when the higher rate of MSW compost was applied. The control showed values of Zn concentration in plant within a deficient range. In general, composted urban wastes treatments had increased Zn concentration values, which were within the sufficiency range. Both treatments with MSW compost increased Cu and Zn uptake in comparison with MSW‐SS co‐compost treatments. At the postharvest, all composted urban wastes treatments increased significantly DTPA‐extractable Cu content in soil with respect to the control; it was also significant the increase in AAAc‐EDTA‐extractable Cu in soil produced by the addition of the higher rate of MSW compost. The application of composted urban wastes increased significantly DTPA‐extractable and AAAc‐EDTA‐extractable Zn contents in soil versus the control, except for the lower rate of MSW‐SS co‐compost. The values of DTPA‐extractable/total ratio for Cu and Zn were under 10%, except for the treatment applying the higher rate of MSW compost which promoted higher values. The values of AAAc‐EDTA‐extractable/total ratio for Cu were above 10% in all treatments including the control. This tendency was also observed in AAAc‐EDTA‐extractable/total ratio for Zn when applying both rates of MSW compost or the higher rate of MSW‐SS co‐compost.  相似文献   
766.
Abstract

A dynamic model based on the linear systems theory is developed in designing a highly cybernetic farming strategy to efficiently manage residuals generated in farm ecosystems. A linear cybernetic model would be used to describe the dynamic behavior of resource flow in the farm ecosystem in which the state variables are resource quantities, and the control variables are residual quantities. The controlled process is defined as the controlled management strategy change. Cybernetic mechanism shows the application of residuals as control measures have determinate effects on the controlled process as along as the farming system is observable and controllable in the control sense. To illustrate the model algorithm the idea is applied to simulate the dynamic response of residual phosphorus concentrations in an integrated pig/corn farming system located in the south Taiwan region. General results show that the residual phosphorous concentration is influenced by farming activities which are controlled by a system of gross input and net output parameters. This paper demonstrates using input‐output analysis technique that residuals generated in the farming system is the most important cybernetic variable, so that the proper management of residuals alone has the potential to maintain future productivity and sustainability.  相似文献   
767.
Abstract

A laboratory experiment was performed in order to evaluate the extent to which metam sodium (MS) applied at two different recommended rates and its degradation product, methyl isothiocyanate ( MITC ), affect soil respiration. Results suggest that MS degradation to MITC was complete within 4 hours and that MITC decomposed quickly in a few days, except in the soil containing high organic matter where it was still present after 15 days. Following the addition of MS, a lag phase appeared in CO2‐C evolution in the soil. It was longer for the higher dose of MS added and for the two soils with low organic C content. The dynamics of the process was described by the Bonde and Rosswall model and by the Gompertz RS E model for the untreated and the MS‐treated soils, respectively.  相似文献   
768.
This paper examines approaches for local resident participation in community‐based natural resource management (CBNRM); focusing particularly on the potential impacts that local participation imposes on the natural environment. This study used qualitative methods to collect data, and selected Meqmegi, an indigenous community in Taiwan, as a case study. The findings indicate that many opportunities can be created that stimulate a community to participate in natural resource management; moreover, residents are prone to use their own ways to participate. Therefore, although local participation is praised for its people‐oriented way of natural resource management, impacts from the participation process will ultimately be imposed on the environment. We suggest that more consideration be given to the environmental conditions during the process of local participation via CBNRM to make sure that impacts on the environment are positive, and lead to a truly sustainable future.  相似文献   
769.
Abstract: Conservation interventions require evaluation to understand what factors predict success or failure. To date, there has been little systematic investigation of the effect of social and cultural context on conservation success, although a large body of literature argues it is important. We investigated whether local cultural context, particularly local institutions and the efforts of interventions to engage with this culture significantly influence conservation outcomes. We also tested the effects of community participation, conservation education, benefit provision, and market integration. We systematically reviewed the literature on community‐based conservation and identified 68 interventions suitable for inclusion. We used a protocol to extract and code information and evaluated a range of measures of outcome success (attitudinal, behavioral, ecological, and economic). We also examined the association of each predictor with each outcome measure and the structure of predictor covariance. Local institutional context influenced intervention outcomes, and interventions that engaged with local institutions were more likely to succeed. Nevertheless, there was limited support for the role of community participation, conservation education, benefit provision, and market integration on intervention success. We recommend that conservation interventions seek to understand the societies they work with and tailor their activities accordingly. Systematic reviews are a valuable approach for assessing conservation evidence, although sensitive to the continuing lack of high‐quality reporting on conservation interventions.  相似文献   
770.
Perceptions, knowledge and mitigation are factors that might play a role in preventing injury and loss of life during a major earthquake.2 Little is known about the relationships between different demographic and educational parameters and these factors. A national representative sample of 495 adults was investigated in order to determine the relationship between demographic and educational parameters in terms of the perceived threat, perceived coping, knowledge and mitigation of earthquakes in Israel. Compared to females, males perceived the threat of earthquakes to be lower (t=3.183, p=0.002), manifested higher levels of perceived coping (t=2.55, p=0.011), and had higher levels of earthquake related knowledge (t=2.047, p=0.041). We conclude that there are gender differences in perceptions and knowledge regarding earthquakes.  相似文献   
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