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1.
Conservation and development practitioners increasingly promote community forestry as a way to conserve ecosystem services, consolidate resource rights, and reduce poverty. However, outcomes of community forestry have been mixed; many initiatives failed to achieve intended objectives. There is a rich literature on institutional arrangements of community forestry, but there has been little effort to examine the role of socioeconomic, market, and biophysical factors in shaping both land‐cover change dynamics and individual and collective livelihood outcomes. We systematically reviewed the peer‐reviewed literature on community forestry to examine and quantify existing knowledge gaps in the community‐forestry literature relative to these factors. In examining 697 cases of community forest management (CFM), extracted from 267 peer‐reviewed publications, we found 3 key trends that limit understanding of community forestry. First, we found substantial data gaps linking population dynamics, market forces, and biophysical characteristics to both environmental and livelihood outcomes. Second, most studies focused on environmental outcomes, and the majority of studies that assessed socioeconomic outcomes relied on qualitative data, making comparisons across cases difficult. Finally, there was a heavy bias toward studies on South Asian forests, indicating that the literature on community forestry may not be representative of decentralization policies and CFM globally.  相似文献   
2.
A changing climate and increasing urbanisation has driven interest in the use of aquifer storage and recovery (ASR) schemes as an environmental management tool to supplement conventional water resources. This study focuses on ASR with stormwater in a low permeability fractured rock aquifer and the selection of water treatment methods to prevent well clogging. In this study two different injection and recovery phases were trialed. In the first phase ~1380 m(3) of potable water was injected and recovered over four cycles. In the second phase ~3300 m(3) of treated stormwater was injected and ~2410 m(3) were subsequently recovered over three cycles. Due to the success of the potable water injection cycles, its water quality was used to set pre-treatment targets for harvested urban stormwater of ≤ 0.6 NTU turbidity, ≤ 1.7 mg/L dissolved organic carbon and ≤ 0.2 mg/L biodegradable dissolved organic carbon. A range of potential ASR pre-treatment options were subsequently evaluated resulting in the adoption of an ultrafiltration/granular activated carbon system to remove suspended solids and nutrients which cause physical and biological clogging. ASR cycle testing with potable water and treated stormwater demonstrated that urban stormwater containing variable turbidity (mean 5.5 NTU) and organic carbon (mean 8.3 mg/L) concentrations before treatment could be injected into a low transmissivity fractured rock aquifer and recovered for irrigation supplies. A small decline in permeability of the formation in the vicinity of the injection well was apparent even with high quality water that met turbidity and DOC but could not consistently achieve the BDOC criteria.  相似文献   
3.
In this Concepts & Synthesis paper, we expand the definition of chronodisruption in humans by proposing that it can be operationalized as the split nexus of internal and external times. With this premise, we suggest how chronotype may be used as a temporal marker (chronomarker) of exposure to chronodisruption in studies of cancer, and beyond, offer cancer risk predictions for observational research on the basis of a chronotype-related hypothesis and corollary, and point to first empirical data in humans. In an a priori way, we examine possible outcomes and perspectives for preventive measures following from our rationale and the suggested chronobiology-driven studies and close with overall advances of chronodisruption research.  相似文献   
4.
The UK is reportedly an international leader in the application of environmental policy appraisal (EPA). From the late 1980s until 2004, UK central government sought to produce ex ante assessments of the potential environmental impacts of different policy options. Critics maintain that EPA had a very limited impact on policy-making activities in Whitehall departments. However, the empirical basis for these claims is surprisingly thin. This paper seeks to better understand what facilitated or retarded EPA by looking at its use in Whitehall, with the aim being to draw lessons for the UK's new and more integrated appraisal regime, as well as similar systems in the European Union. The paper finds that the implementation of EPA was both weak and highly sectorised, and that there is an underlying resistance to policy appraisal per se in Whitehall. These weaknesses urgently need to be addressed otherwise new systems of integrated appraisal will not deliver what is expected of them.  相似文献   
5.
ABSTRACT

This study investigated spatio-temporal variations of selected pesticide residues in the Kurose River in Higashi-Hiroshima city (Hiroshima Prefecture), Japan. Water samples were collected from the river at seven sites every month for 1 year (March 2016 to February 2017). Pesticide residues were extracted from the samples by a solid phase extraction using Sep Pack C18 cartridges. Once extracted, the samples were analyzed for cyanazine, simetryn, fenarimol, isoprothiolane, and diazinon using a reversed-phase high-performance liquid chromatography ultraviolet visible (HPLC-UV Vis) system. The limits of detection were 3.60, 4.10, 2.80, 6.50, and 7.30 ng L-1 for cyanazine, simetryn, fenarimol, isoprothiolane, and diazinon, respectively. Good recovery rates (88%–102%), and mean percent relative standard deviation range (1.00%–5.70%) (n = 6) were obtained with a spiking at 0.20 µg L-1. The maximum concentrations of 282, 391, 60, 1086, and 1194 ng L-1 were obtained for cyanazine, simetryn, isoprothiolane, fenarimol, and diazinon, respectively. Cyanazine was the most frequently detected pesticide (64% of the samples, n = 84), followed by simetryn (58%), and then diazinon (57%). The highest and lowest pesticide concentrations were measured during the periods May–June, and January–February, respectively. Principal component analysis revealed three principal components in which the pesticides were linked to dissolved organic matter and total suspended solids. The major water quality parameters (electrical conductivity, pH, Na+, K+, Mg2+, Ca2+, NH4+, NO3?, Cl?, SO42?, NO2?, and temperature) showed no clear trends for these pesticides. The presence of simetryn and isoprothiolane was largely attributed to rice paddy farms, whereas diazinon was associated mostly with vegetable farms and orchards. The diazinon and isoprothiolane patterns were consistent with their use of controlling insects and fungi in the prefecture. The maximum diazinon concentration detected was higher than the human safe level specified by the European Union (100 ng L-1) in Council Directive 98/83/EC. This is of concern because of the bioconcentration potential of these residues in fish and other marine animals consumed by humans.  相似文献   
6.
Light,timing of biological rhythms,and chronodisruption in man   总被引:3,自引:2,他引:3  
This paper reviews abundant evidence suggesting that causes and course of aging and cancers can be considered as being both light- and rhythm-related. We define chronodisruption as a relevant disturbance of orderly biological rhythms over days and seasons and years in man. Light is the primary external mediator and melatonin a primary internal intermediary of such disturbances, which can result in earlier deaths via premature aging and cancers. We conclude that experimental and epidemiological research can provide further insights into common denominators of these chronic processes and may offer novel and uniform targets for prevention.  相似文献   
7.
The ontogeny of diving and foraging behavior of northern fur seal pups from a stable population on Bering Island, Russia, was recorded with animal-borne instruments during their first few months at sea, a critical period during their first year at sea. Thirty-five pups were instrumented with satellite-linked time-depth recorders and stomach temperature pills. Diving occurred predominantly at night with deeper and longer dives as the pups matured. Mean dive depths were correlated with lunar illumination, whereas mean dive durations were also correlated with time of day and sex. Foraging success did not differ between sexes, and there was no relationship between meal size (as indicated by feeding event duration and minimum stomach temperature) and lunar illumination fraction or maximum foraging depth. Although most pups were able to successfully forage within 3 days of starting their migration, the number of feeding events recorded each day remained low (mean 1.6 events day?1). There was no indication of an appreciable increase in meal size after the first 2 weeks of the migration despite an increase in dive frequency and depth. The results are consistent with observations that pups do not gain mass during their first year and emphasize the risk of starvation from infrequent foraging in cold water.  相似文献   
8.
We reviewed organophosphorus pesticide use in Japan between 1982 and 2016 using data from the National Institute of Environmental Studies. Organophosphorus pesticide concentrations in river water throughout Japan were taken from the literature, and risk assessments were performed for some organophosphorus pesticides based on risk quotients and hazard quotients. Assessments were performed for 20 common pesticides, including insecticides, fungicides, and herbicides. The amounts used decreased in the order: insecticides?>?herbicides?>?fungicides. Organophosphorus insecticide and fungicide use have decreased over the last four decades, but organophosphorus herbicide use has increased. During this period, annual organophosphorus pesticide use was the highest for chlorpyrifos (105,263?tons/year) and the lowest for glyphosate-sodium (8?tons/year). The ecotoxicological risk assessment indicated that diazinon and fenitrothion posed strong risks to the Japanese aquatic environment, and chlorpyrifos and malathion have moderate risks. None of the pesticides that were assessed posed significant risks to humans. Continued use of organophosphorus pesticides in Japan may cause strong risks to aquatic environments. These risks should be reassessed periodically.  相似文献   
9.
Five studies of the background level of several perfluorocarbon compounds in Europe are here presented together with measurements from the European Tracer Experiment (ETEX). The tracers used during the two ETEX tracer releases were the perfluorocarbons (PFCs); perfluoromethylcyclohexane (C7F14, PMCH) and perfluoromethylcyclopentane (C6F12, PMCP). Their background concentrations were detected by using both passive and active sampling techniques, to define the spatial and temporal variation of the PFCs over Europe. Also the background variations of four isomers of the PFC compound perfluorodimethylcyclohexane (C8F16, PDCH) were studied. The results were compared to other PFC tracer studies in the U.S.A. and Europe. The mean and median values of the measured PFCs were found to vary slightly and randomly in space and time. They were found to be higher and to have a larger standard deviation than the measurements from the American studies. The background concentrations were still found to be low and stable enough for PFCs to be highly suitable for use in tracer studies. The following concentrations were found: PMCP; 4.6±0.3 fl ℓ-1, PMCH: 4.6±0.8 fl ℓ-1, ocPDCH: 0.96±0.33 fl ℓ-1, mtPDCH: 9.3±0.8 fl ℓ-1, mcPDCH: 8.8±0.8 fl ℓ-1, ptPDCH: 6.1±0.8 fl ℓ-1. A study of the correlation between the measured PFC compounds showed a significant correlation between most of the compounds, which indicate that there are no major PFC sources in Europe.  相似文献   
10.
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