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101.
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Conservation easements are the fastest growing private conservation strategy in the United States. However, mechanisms to assess private land conservation as well as their support by the general public are not well understood. This study uses the ecosystem services framework for assessing existing private lands in Idaho and identifies areas for future conservation easements. Using conservation targets of the land trust as a guide for selecting ecosystem services, we (a) mapped the spatial delivery of conservation targets across public and private lands, (b) explored public awareness in terms of social importance and vulnerability, and (c) mapped future priority areas by characterizing conservation bundles. We found that public lands provided the highest levels of conservation targets, and we found no difference in conservation target provision between private areas and conservation easements. The spatial characterization of conservation target bundles identified potential future priority areas for conservation easements, which can guide planning of land trust conservation efforts.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01323-x) contains supplementary material, which is available to authorized users.  相似文献   
103.
Squat lobster populations found in the Humboldt Current System over the continental shelf from ~28 to 37°S release pelagic larvae in sub-surface cold (~11 °C) hypoxic waters. Larvae subsequently spread throughout the water column encountering both normoxic and hypoxic conditions. We analyzed some short- and long-term responses of Pleuroncodes monodon larval metabolism to hypoxia at 11 °C. Routine and postprandial aerobic respiration rates were lower in hypoxia than in normoxia for all zoeal stages. Zoea V oxyconformed, while megalopae oxyregulated down to very low oxygen concentrations. Throughout zoea I development, the rate of nitrogen (protein) accumulation in zoea I was lower, and C:N ratios were higher under hypoxic conditions than in normoxia. Citrate synthase (CS) and malate dehydrogenase (MDH) apparent specific activities (as indicators of aerobic and metabolic potentials, respectively) decreased and remained at the same level, respectively, throughout zoea I reared under hypoxic conditions. Anaerobic to aerobic potential (lactate dehydrogenase (LDH)/CS) was higher in organisms reared under hypoxia, and MDH/LDH potential ratios were characteristic of organisms tolerant to hypoxia. In spite of P. monodon zoea endurance and metabolic adaptations to decreasing oxygen tensions, intense hypoxia as such of their release site would affect their overall condition especially toward the end of the molt cycle. Our results indicate the importance of considering the interaction between environmental oxygen variability and recruitment success.  相似文献   
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105.
Advances in surfactants for agrochemicals   总被引:2,自引:0,他引:2  
Pesticide efficacy is improved by surfactants. Increase in the foliar uptake is particularly useful for herbicides, growth regulators and defoliants, because less active compounds are needed, thus decreasing cost and pollution. Therefore, the choice of the adjuvant in an agrochemical formulation is crucial. The surfactants commonly used as adjuvants include anionic, non-ionic, amphoteric and cationic surfactants. This review analyses the role and properties of the new adjuvants for agriculture and the improvement of the ecotoxicity profile of the pesticide formulations in glyphosate formulation.  相似文献   
106.
Environmental Modeling & Assessment - Costa Rica has set a very ambitious Nationally Determined Contribution (NDC). Despite the low-carbon footprint of its power sector, the goal set in its NDC...  相似文献   
107.
Ozone and a Fe2+/TiO2-based catalyst were examined in the degradation of a synthetic solution of benzene toluene and xylene (BTX) in an advanced oxidation process (AOP). The catalyst beads were made from the slurry waste of aluminum production process, by inserting the TiO2 content and subsequent calcination. The reduction of the BTX concentration load was monitored by the reduction of chemical oxygen demand (COD) and BTX concentration. Different levels were used on factors: pH, time of treatment, initial concentration of BTX, and percentage of TiO2. The process was conducted in a bubble column reactor with the insertion of catalyst beads. A response surface methodology technique (CCD) was used to build a model based on COD reduction results. The model was optimized using the normal-boundary intersection (NBI) algorithm to maximize COD reduction and minimize the variance attributed to the process. Optimization led to COD reductions of 80% in 2 h of experiment. Correlation analysis of coefficient models from experimental data R2adj was 0.9966, showing a good fit of model data. In the optimized conditions, the possible increase of the biodegradability ratio of the BTX solution, through the biochemical oxygen demand (BOD) and COD, was also analyzed. Under pre-treatment conditions, the BOD/COD ratio was 0.13. After the treatment, it increased to 0.56.
Graphical abstract ?
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108.
Environmental Science and Pollution Research - The current study has assessed whether the oral and/or dermal exposure of C57Bl/6 J mice to tannery effluent (a complex pollutant consisting of...  相似文献   
109.
Organotin compounds (OTs) were used in antifouling paints for more than four decades. However, due to their widespread intensive use and high toxicity, undesirable effects in non-target marine organisms have been detected since the early 1980s. Consequently, the International Maritime Organization banned new maritime applications of these products on January 1, 2003 and their presence on ship hulls from January 1, 2008. Although extensively studied in Europe, North America, Oceania, and Asia, environmental levels and effects of organotin contamination are still poorly known for South America. Thus, the current review aimed to present the actual status of this problem in South America by summarizing and comparing the available data in the literature. An overview of the OTs concentrations in sediment and biota and their effects, mainly imposex in marine gastropods, are presented. This work showed that in Atlantic coastal areas of South America there are “hot spots” of OTs contamination, similar to that observed in industrialized countries of Northern Hemisphere. On the other hand, the number of accomplished studies in the Pacific coast is extremely low. Despite the limitation on studies about OTs environmental levels and their related effects, the available data pointed out for a widespread TBT contamination along the South American coastal areas. Therefore, the establishment of baselines of organotin contamination in the Pacific coast and the implementation of temporal trend studies in the South American coastal areas is crucial to verify the effectiveness of local regulations and OTs global ban, and to map the most sensitive areas related to present and future antifouling impacts.  相似文献   
110.
Endosulfan is an insecticide which has been widely used in agriculture. The technical grade material consists of two isomers (alpha and beta). Under natural environmental conditions, endosulfan is metabolized through oxidation and the main metabolite in the environment is endosulfan sulfate. Most ecotoxicology research has been conducted with technical grade endosulfan to determine effects on non-target aquatic organisms. Little data on the effects of endosulfan sulfate on aquatic organisms are available in the literature. This study characterizes endosulfan sulfate bioconcentration and depuration in mosquito fish (Gambusia affinis). During the study, G. affinis was exposed to an environmentally relevant endosulfan sulfate concentration of 0.25 μg L−1 for 5 weeks (uptake phase) followed by a 3-week period (depuration phase) in clean water. This study found that G. affinis bioconcentrated endosulfan sulfate. During the exposure phase, fish tissue concentrations of endosulfan sulfate increased with time up to 730 μg kg−1 dw or 215 μg kg−1 ww. The bioconcentration data followed Michaelis-Menten kinetics better than the one-compartment first order kinetics (1-CFOK). Using these models, the bioconcentration factors for endosulfan sulfate-exposed G. affinis were from 687 to 888  L kg−1 in wet weight or 2263 to 2936 L kg−1 in dry weight. During the depuration phase, endosulfan sulfate concentrations in tissue significantly decreased and the data followed first order kinetics. The half-life of endosulfan sulfate in G. affinis was about 9 d. There was no significant difference in standard length or weight between control and exposed fish. The growth data followed the von Bertalanffy growth model. However, the condition factor of exposed fish increased with time during the exposure phase.  相似文献   
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