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331.
Abstract

Acute bioassay tests on the toxic effects of the insect larvicide Abate® (temephos) on the mouth brooder cichlid fish Tilapia melanopleum and the dragonfly larvae (Odonata) Neurocordulia virginiensis were conducted in static non renewal toxicity test set ups. The 96h‐LC50 (95% confidence intervals) was 30.2 (20.5‐ 44.20) mg/L for the fish and 2.0 (1.16–2.0) mg/L for the dragonfly larvae. The dragonfly larvae were 15 times more susceptible to the larvicide than the tilapia. The calculated NOEC (No Observable Effect Concentration) was 14.1 mg/L for the fishand less than 1.0 mg/L for the insect larvae. The estimated ‘safe’ concentration of the pesticide to the fish was 3.0 mg/L and 0.2 mg/L for insect larvae. These figures are far above the concentrations approved for use in the control of mosquito larvae(0.0004–0.01 mg/L). It appears that the application of toxic levels of the insecticide for the elimination of some aquatic invertebrates may be ‘safe’ for normal survival, growth and reproduction offish and some aquatic insect larvae.  相似文献   
332.
Abstract: We examined the efficacy of a translocation program in which large numbers of leopards (Panthera pardus fusca) were trapped in human‐dominated landscapes where livestock attacks were common and human attacks rare and released into adjoining forested areas in an attempt to reduce leopard presence and mitigate conflicts at the capture site. In the year starting in February of 2001, 29 leopards were captured in the human‐dominated rural landscape of the Junnar region (4275 km2, 185 people/km2), Maharashtra, India, and released an average of 39.5 km away in adjoining forests. Eleven leopards were also relocated to the same forests from other districts. Prior to the large‐scale translocation program, an average of four leopard attacks on humans occurred each year between 1993 and 2001. After the translocation program was initiated, the average increased substantially to 17 attacks. Linear and logistic models showed that attack frequency increased in Junnar following nearby releases of leopards and decreased when leopards were removed for releases far away; that attacks became more lethal when the number of leopards introduced from other districts increased; and that attacks were most likely to occur in the regions where the largest number of leopards had been introduced from other areas. These results suggest that leopards did not stay at the release sites and that translocation induced attacks on people. Potential explanations for these results include increased aggression induced by stress of the translocation process, movement through unfamiliar human‐dominated landscapes following release, and loss of fear of humans due to familiarity with humans acquired during captivity. Our results show that reactive solutions to attacks on humans by leopards, such as translocation, could in fact increase human–leopard conflict. Measures to reduce human–carnivore conflicts may include more effective compensation procedures to pay livestock owners for the loss of animals to predation by carnivores, providing better methods of protection for livestock, and encouraging greater social acceptance of the presence of carnivores in human‐dominated landscapes.  相似文献   
333.
Abstract: Social, economic, and ecological criteria contribute to the successful design, implementation, and management of marine protected areas (MPAs). In the context of California's Marine Life Protection Act Initiative, we developed a set of methods for collecting, compiling, and analyzing data about the spatial extent and relative economic importance of commercial and recreational fishing. We interviewed 174 commercial fishers who represented the major fisheries in the initiative's north‐central coast region, which extends from Point Arena south to Pigeon Point. These fishers provided data that we used to map the extent of each of the fishing grounds, to weight the relative importance of areas within the grounds, to characterize the operating costs of each fishery, and to analyze the potential economic losses associated with proposed marine protected areas. A regional stakeholder group used the maps and impact analyses in conjunction with other data sets to iteratively identify economic and ecological trade‐offs in designations of different areas as MPAs at regional, port, and fishery extents. Their final proposed MPA network designated 20% of state waters as MPAs. Potential net economic loss ranged from 1.7% to 14.2% in the first round of network design and totaled 6.3% in the final round of design. This process is a case study in the application of spatial analysis to validate and integrate local stakeholder knowledge in marine planning.  相似文献   
334.
Abstract

Biodegradation of the fatty acylamino acids by Fusarium culmorum, measured in terms of the release of radioactive aspartate and lysine, occurred maximally at pH 6.5 and pH 7.0, respectively in 10 day cultures. Thirty‐six percent and twenty‐four percent of the total radioactivity recovered were in released aspartate and lysine, respectivley at 30°C. Twenty degrees (C) was the minimum temperature for biodegradation of these compounds by F. culmorum. Greater degradation was observed at 15°C and 30°C. The data suggest the activity of hydrolytic isoenzymes, with optima at different pH's and temperatures, operating in the biodegradation process.  相似文献   
335.
Abstract: Habitat loss is silently leading numerous insects to extinction. Conservation efforts, however, have not been designed specifically to protect these organisms, despite their ecological and evolutionary significance. On the basis of species–host area equations, parameterized with data from the literature and interviews with botanical experts, I estimated the number of specialized plant‐feeding insects (i.e., monophages) that live in 34 biodiversity hotspots and the number committed to extinction because of habitat loss. I estimated that 795,971–1,602,423 monophagous insect species live in biodiversity hotspots on 150,371 endemic plant species, which is 5.3–10.6 monophages per plant species. I calculated that 213,830–547,500 monophagous species are committed to extinction in biodiversity hotspots because of reduction of the geographic range size of their endemic hosts. I provided rankings of biodiversity hotspots on the basis of estimated richness of monophagous insects and on estimated number of extinctions of monophagous species. Extinction rates were predicted to be higher in biodiversity hotspots located along strong environmental gradients and on archipelagos, where high spatial turnover of monophagous species along the geographic distribution of their endemic plants is likely. The results strongly support the overall strategy of selecting priority conservation areas worldwide primarily on the basis of richness of endemic plants. To face the global decline of insect herbivores, one must expand the coverage of the network of protected areas and improve the richness of native plants on private lands.  相似文献   
336.
Abstract: Recent literature on systematic conservation planning has focused strongly on economics. It is a necessary component of efficient conservation planning because the question is about effective resource allocation. Nevertheless, there is an increasing tendency toward economic factors overriding biological considerations. Focusing too narrowly on economic cost may lead us back toward solutions resembling those obtained by opportunistic choice of areas, the avoidance of which was the motivation for development of systematic approaches. Moreover, there are many overlooked difficulties in incorporating economic considerations reliably into conservation planning because available economic data and the free market are complex. For instance, economies based on free markets tend to be shortsighted, whereas biodiversity conservation aims far into the future. Although economic data are necessary, they should not be relied on too heavily or considered separately from other sociopolitical factors. We suggest focusing on development of more‐comprehensive ecological‐economic modeling, while not forgetting the importance of purely biological analyses that are needed as a point of reference for evaluating conservation outcomes.  相似文献   
337.
Abstract

Carbofuran was applied over seeded rutabaga cv. York and residues (corrected for recovery) of carbofuran, 3‐hydroxy‐ and 3‐ketocarbofuran in the harvested roots averaged 0.15, 0.23 and 0.07 ppm in peel and 0.09, 0.14 and 0.05 ppm in pulp, respectively. Samples were extracted by hot acid digestion, partitioned in methylene chloride and cleaned up on Florisil. The 3‐hydroxy‐carbofuran was ethoxylated and the compounds were converted into their dinitrophenyl ethers and analysed by electron capture gas chromatography using 3% OV‐3 column.  相似文献   
338.
Yang, Yang, Theodore A. Endreny, and David J. Nowak, 2011. iTree‐Hydro: Snow Hydrology Update for the Urban Forest Hydrology Model. Journal of the American Water Resources Association (JAWRA) 47(6):1211–1218. DOI: 10.1111/j.1752‐1688.2011.00564.x Abstract: This article presents snow hydrology updates made to iTree‐Hydro, previously called the Urban Forest Effects—Hydrology model. iTree‐Hydro Version 1 was a warm climate model developed by the USDA Forest Service to provide a process‐based planning tool with robust water quantity and quality predictions given data limitations common to most urban areas. Cold climate hydrology routines presented in this update to iTree‐Hydro include: (1) snow interception to simulate the capture of snow by the vegetation canopy, (2) snow unloading to simulate the release of snow triggered by wind, (3) snowmelt to simulate the solid to liquid phase change using a heat budget, and (4) snow sublimation to simulate the solid to gas phase via evaporation. Cold climate hydrology routines were tested with research‐grade snow accumulation and weather data for the winter of 1996‐1997 at Umpqua National Forest, Oregon. The Nash‐Sutcliffe efficiency for open area snow accumulation was 0.77 and the Nash‐Sutcliffe efficiency for under canopy was 0.91. The USDA Forest Service offers iTree‐Hydro for urban forest hydrology simulation through http://www.iTreetools.org .  相似文献   
339.
Abstract

Laboratory experiments were conducted to study the degradation of acifluorfen 5‐[2‐chloro‐4‐ (trifluoromethyl)‐phenoxy]‐2‐nitrobenzoic acid by a mixed microbial population.

Concentrations of acifluorfen up to 100 mg/1 had no inhibitory effect on the growth of microbial culture.

The microorganisms degraded acifluorfen through a cometabolic process in presence of 2‐nitrobenzoate.

The degradation rate of acifluorfen, determined by liquid chromatography analysis in batch cultures incubated under oxygen and oxygen‐limited conditions were compared. The degradation was slower under oxygen than oxygen‐limited conditions. Aminoacifluorfen was produced in both conditions.  相似文献   
340.
Cochran, Bobby and Charles Logue, 2011. A Watershed Approach to Improve Water Quality: Case Study of Clean Water Services’ Tualatin River Program. Journal of the American Water Resources Association (JAWRA) 47(1):29‐38. DOI: 10.1111/j.1752‐1688.2010.00491.x Abstract: Over the last five years, Clean Water Services developed and implemented a program to offset thermal load discharged from its wastewater facilities to the Tualatin River by planting trees to shade streams and augmenting summertime instream flows. The program has overcome challenges facing many of the nation’s water quality trading programs to not only gain consensus on the frameworks needed to authorize trading, but also provide a broad range of ecosystem services. This paper compares the Tualatin case study with some of the commonly cited factors of successful trading programs.  相似文献   
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