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431.
Workers and fence-line communities have been the first to benefit from the substantial reductions in toxic chemical use and byproducts in industrial production resulting from the Massachusetts Toxics Use Reduction Act (TURA). As TURA motivates reformulation of products as well as retooling of production processes, benefits could extend more broadly to large-scale reductions in everyday exposures for the general population. Household exposure studies, including those conducted by Silent Spring Institute, show that people are exposed to complex mixtures of indoor toxics from building materials and a myriad of consumer products. Pollutants in homes are likely to have multiple health effects because many are classified as endocrine disrupting compounds (EDCs), with the ability to interfere with the body’s hormone system. Product-related EDCs measured in homes include phthalates, halogenated flame retardants, and alkylphenols. Silent Spring Institute’s chemical analysis of personal care and cleaning products confirms many are potential sources of EDCs, highlighting the need for a more comprehensive toxics use reduction (TUR) approach to reduce those exposures. Toxics use reduction targeted at EDCs in consumer products has the potential to substantially reduce occupational and residential exposures. The lessons that have emerged from household exposure research can inform improved chemicals management policies at the state and national levels, leading to safer products and widespread health and environmental benefits.  相似文献   
432.
Blood-sucking leeches have been used for medical purposes in humans for hundreds of years. Accordingly, one of the most prominent species has been named Hirudo medicinalis by Carl Linne in 1758. Feeding on vertebrate blood poses some serious problems to blood-sucking ectoparasites, as they have to penetrate the body surface of the host and to suppress the normal reactions of the host to such injuries (swelling, pain, inflammation) to remain undetected during the feeding period. Furthermore, the parasites have to take measures to inhibit the normal reactions in host tissues to blood vessel damage, namely hemostasis and blood coagulation (platelet aggregation and activation, activation of thrombin and formation of fibrin clots). During evolution, leeches have acquired the ability to control these processes in their hosts by transferring various bioactive substances to the host. These substances are supposedly produced in unicellular salivary gland cells and injected into the wound at the feeding site through tiny salivary ductule openings in the jaws that the leech uses to slice open the host body surface and to cut blood vessels in the depth of the wound. This review summarizes current knowledge about the salivary gland cells and the biological effects of individual saliva components as well as hints to the potential usefulness of some of these compounds for medical purposes.  相似文献   
433.
Groundwater in sufficient amounts and of suitable quality is essential for potable water supplies, crop irrigation and healthy habitats for plant and animal biocenoses. The groundwater resource is currently under severe pressure from land use and pollution and there is evidence of dramatic changes in aquifer resources in Europe and elsewhere, despite numerous policy measures on sustainable use and protection of groundwater. Little is known about how such changes affect groundwater dependent ecosystems (GDEs), which include various aquatic and terrestrial ecosystems above ground and inside the aquifer. Future management must take this uncertainty into account. This paper focuses on multiple aspects of groundwater science, policy and sustainable management. Examples of current management methods and practices are presented for selected aquifers in Europe and an assessment is made of the effectiveness of existing policies such as the European Water Framework Directive and the Habitat Directive in practice and of how groundwaters and GDEs are managed in various conditions. The paper highlights a number of issues that should be considered in an integrated and holistic approach to future management of groundwater and its dependent ecosystems.  相似文献   
434.
A Tier I Sediment Ecological Risk Assessment of profundal lake sediment contaminated by diffuse pollution of heavy metals and POPs deposited from the atmosphere was completed. The concentrations of seven heavy metals and four groups of POPs (OCs, PCBs, PAHs, PBDEs) were determined in the profundal sediment of ten lakes in the United Kingdom and two sediment toxicity tests completed (chironomid survival and emergence and cladoceran survival and reproduction). The results showed that around half the lakes are at least moderately contaminated by Pb, Zn, Cd, As and PAHs deposited from the atmosphere and the toxicity quotient suggests that the contaminants of concern are Pb, As and PAHs, and not the other metals nor OCs and PCBs. There was toxicity in the sediment of four of the lakes. The Probable Effect Concentration Quotient values indicated that metals in the sediments of Scoat Tarn, Agden Reservoir and Llyn Llagi were likely to be responsible for the laboratory toxicity found in these lakes, with PAHs also contributing in Agden Reservoir.  相似文献   
435.
Beeswaxes of honeybee species share some homologous neutral lipids; but species-specific differences remain. We analysed behavioural variation for wax choice in honeybees, calculated the Euclidean distances for different beeswaxes and assessed the relationship of Euclidean distances to wax choice. We tested the beeswaxes of Apis mellifera capensis, Apis florea, Apis cerana and Apis dorsata and the plant and mineral waxes Japan, candelilla, bayberry and ozokerite as sheets placed in colonies of A. m. capensis, A. florea and A. cerana. A. m. capensis accepted the four beeswaxes but removed Japan and bayberry wax and ignored candelilla and ozokerite. A. cerana colonies accepted the wax of A. cerana, A. florea and A. dorsata but rejected or ignored that of A. m. capensis, the plant and mineral waxes. A. florea colonies accepted A. cerana, A. dorsata and A. florea wax but rejected that of A. m. capensis. The Euclidean distances for the beeswaxes are consistent with currently prevailing phylogenies for Apis. Despite post-speciation chemical differences in the beeswaxes, they remain largely acceptable interspecifically while the plant and mineral waxes are not chemically close enough to beeswax for their acceptance.  相似文献   
436.
We aimed to identify priority research questions in the field of biodiversity, ecosystem services and sustainability (BESS), based on a workshop held during the NRG BESS Conference for Early Career Researchers on BESS, and to compare these to existing horizon scanning exercises. This work highlights the need for improved data availability through collaboration and knowledge exchange, which, in turn, can support the integrated valuation and sustainable management of ecosystems in response to global change. In addition, clear connectivity among different research themes in this field further emphasizes the need to consider a wider range of topics simultaneously to ensure the sustainable management of ecosystems for human wellbeing. In contrast to other horizon scanning exercises, our focus was more interdisciplinary and more concerned with the limits of sustainability and dynamic relationships between social and ecological systems. The identified questions could provide a framework for researchers, policy makers, funding agencies and the private sector to advance knowledge in biodiversity and ES research and to develop and implement policies to enable sustainable future development.  相似文献   
437.
Kay AD  Mankowski J  Hobbie SE 《Ecology》2008,89(5):1188-1194
Fires can generate spatial variation in trophic interactions such as insect herbivory. If trophic interactions mediated by fire influence nutrient cycling, they could feed back on the more immediate consequences of fire on nutrient dynamics. Here we consider herbivore-induced effects on oak litter quality and decomposition within a long-term manipulation of fire frequency in central Minnesota, USA. We focused on bur oak (Quercus macrocarpa) trees, which are common across the fire frequency gradient and are often heavily infested with either lace bugs (Corythuca arcuata) or aphids (Hoplochaithropsus quercicola). We used targeted exclusion to test for herbivore-specific effects on litter chemistry and subsequent decomposition rates. Lace bug exclusion led to lower lignin concentrations in litterfall and subsequently accelerated decomposition. In contrast, aphid exclusion had no effect on litterfall chemistry or on decomposition rate, despite heavy infestation levels. Effects of lace bug herbivory on litterfall chemistry and decomposition were similar in burned and unburned areas. However, lace bug herbivory was much more common in burned than in unburned areas, whereas aphid herbivory was more common in unburned areas. These results suggest that frequent fires promote oak-herbivore interactions that decelerate decomposition. This effect should amplify other influences of fire that slow nitrogen cycling.  相似文献   
438.
REDD+ remains a critical tool for dealing with increasing levels of atmospheric carbon dioxide. Like other global-level initiatives, REDD+ has strong supporters and critics. Despite the division over its merits, little has been done to understand how a national-level audience responds to the program’s arrival in a partner country and which players drive a program’s implementation. Here we coded the archives of two Guyanese newspapers to identify the policy actors, institutions, and concepts (players) that drove the implementation of the country’s Low Carbon Development Strategy (LCDS). Two groups of players—super-key and key—dictated the direction of the LCDS implementation. Super-key players used the state-owned media to advocate their positions, while players who felt they would be punished by the LCDS implementation published their positions in the privately-owned media. Therefore, like responses to other global-level environmental challenges, views around the LCDS were divided.  相似文献   
439.

The feasibility of using floating treatment wetlands (FTWs) to treat runoff typical of commercial nurseries was investigated using two 8-week trials with replicated mesocosms. Plants were supported by Beemat rafts. Five monoculture treatments of Agrostis alba (red top), Canna × generalis ‘Firebird’ (canna lily), Carex stricta (tussock sedge), Iris ensata ‘Rising Sun’ (Japanese water iris), Panicum virgatum (switchgrass), two mixed species treatments, and an unplanted control were assessed. These plant species are used for ornamental, wetland, and biofuel purposes. Nitrogen (N) and phosphorus (P) removals were evaluated after a 7-day hydraulic retention time (HRT). N removal (sum of ammonium-N, nitrate-N, and nitrite-N) from FTW treatments ranged from 0.255 to 0.738 g·m?2·d?1 (38.9 to 82.4% removal) and 0.147 to 0.656 g·m?2·d?1 (12.9 to 59.6% removal) for trials 1 and 2, respectively. P removal (phosphate-P) ranged from 0.052 to 0.128 g·m?2·d?1 (26.1 to 64.7% removal) for trial 1, and 0.074 to 0.194 g·m?2·d?1 (26.8 to 63.2% removal) for trial 2. Panicum virgatum removed more N and P than any other FTW treatment and the control in both trials. Results show that species selection and timing of FTW harvest impact the rate and mass of nutrient remediation. FTWs can effectively remove N and P from runoff from commercial nurseries.

  相似文献   
440.
In this review paper, we aim to describe the potential for, and the key challenges to, applying PES projects to mangroves. By adopting a “carbocentric approach,” we show that mangrove forests are strong candidates for PES projects. They are particularly well suited to the generation of carbon credits because of their unrivaled potential as carbon sinks, their resistance and resilience to natural hazards, and their extensive provision of Ecosystem Services other than carbon sequestration, primarily nursery areas for fish, water purification and coastal protection, to the benefit of local communities as well as to the global population. The voluntary carbon market provides opportunities for the development of appropriate protocols and good practice case studies for mangroves at a small scale, and these may influence larger compliance schemes in the future. Mangrove habitats are mostly located in developing countries on communally or state-owned land. This means that issues of national and local governance, land ownership and management, and environmental justice are the main challenges that require careful planning at the early stages of mangrove PES projects to ensure successful outcomes and equitable benefit sharing within local communities.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0530-y) contains supplementary material, which is available to authorized users.  相似文献   
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