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341.
Ears evolved in many groups of moths to detect the echolocation calls of predatory bats. Although the neurophysiology of bat detection has been intensively studied in moths for decades, the relationship between sound-induced movement of the noctuid tympanic membrane and action potentials in the auditory sensory cells (A1 and A2) has received little attention. Using laser Doppler vibrometry, we measured the velocity and displacement of the tympanum in response to pure tone pulses for moths that were intact or prepared for neural recording. When recording from the auditory nerve, the displacement of the tympanum at the neural threshold remained constant across frequencies, whereas velocity varied with frequency. This suggests that the key biophysical parameter for triggering action potentials in the sensory cells of noctuid moths is tympanum displacement, not velocity. The validity of studies on the neurophysiology of moth hearing rests on the assumption that the dissection and recording procedures do not affect the biomechanics of the ear. There were no consistent differences in tympanal velocity or displacement when moths were intact or prepared for neural recordings for sound levels close to neural threshold, indicating that this and other neurophysiological studies provide good estimates of what intact moths hear at threshold.  相似文献   
342.
By means of a theoretical model, bootstrap resampling and data provided by the International Commission On Large Dams (ICOLD (2003) World register of dams. http://www.icold-cigb.org) we found that global large dams might annually release about 104 ± 7.2 Tg CH4 to the atmosphere through reservoir surfaces, turbines and spillways. Engineering technologies can be implemented to avoid these emissions, and to recover the non-emitted CH4 for power generation. The immediate benefit of recovering non-emitted CH4 from large dams for renewable energy production is the mitigation of anthropogenic impacts like the construction of new large dams, the actual CH4 emissions from large dams, and the use of unsustainable fossil fuels and natural gas reserves. Under the Clean Development Mechanism of the Kyoto Protocol, such technologies can be recognized as promising alternatives for human adaptations to climate change concerning sustainable power generation, particularly in developing nations owning a considerable number of large dams. In view of novel technologies to extract CH4 from large dams, we estimate that roughly 23 ± 2.6, 2.6 ± 0.2 and 32 ± 5.1 Tg CH4 could be used as an environmentally sound option for power generation in Brazil, China and India, respectively. For the whole world this number may increase to around 100 ± 6.9 Tg CH4.  相似文献   
343.
The estrogenic potency of a wastewater treatment plant(WWTP) was evaluated using chemical and biological analyses,which showed that after the station treatment processes some of the selected endocrine disruptor compounds(EDCs) were still present in the treated effuent(e.g.,bisphenol A,alkylphenols,estrone) .Thus,the most common endocrine EDCs were identified and quantified and the overall estrogenicity of the treated effuent assessed by integrating the results.Male goldfish(Carassius auratus) were used as biological indicators in a 28-day experiment.Vitellogenin(Vtg) ,gonadosomatic and hepatosomatic indices,steroids(17β-estradiol and 11-ketotestosterone) and histopathology were biomarkers used in fish to evaluate WWTP treated effuent estrogenicity,in combination with instrumental analyses.The results showed a significant increase(P0.01) in plasma and liver Vtg,which were significantly correlated(r=0.66;P0.01) .The gonadosmatic index was significantly(P0.01) reduced in exposed fish.The steroid analyses revealed significant elevations in 17β-estradiol and depressed 11-ketotestosterone concentrations.The histological examinations show changes in exposed fish gonads,such as regressed testes and in some cases(43%to 75%) the development of ovo-testis in fish exposed to 50% and 100% treated effuent.  相似文献   
344.
Vamosi SM  Mazer SJ  Cornejo F 《Ecology》2008,89(9):2461-2472
A well-known, but largely untested, prediction in plant reproductive ecology is that dioecious taxa should produce larger, more, higher-quality, or better-defended seeds than cosexual taxa. Using a data set composed of 972 species in 104 families, representing the flora of the Tambopata Wildlife Reserve (Madre de Dios, Peru), we evaluated the first component of this prediction, examining ecological and evolutionary relationships between breeding system and mean seed size with two kinds of tests. First, we conducted cross-species analyses to determine whether species with different breeding systems differed significantly with respect to mean individual seed size. Second, we used a hypothesized phylogeny to identify pairs of the most closely related taxa or clades within the Tambopata community that differed with respect to breeding system. Comparing pair members allowed us to determine whether evolutionary divergence in breeding system (between taxa with unisexual vs. cosexual individuals) was consistently associated with evolutionary change in seed size. In both analyses, we controlled for potentially confounding effects of growth form by examining these relationships within woody and nonwoody taxa. Cross-species analyses revealed that dioecious species produced larger seeds than cosexual species among woody species, shrubs, lianas (each growth form analyzed separately), and all species pooled, but not among trees. Phylogenetically independent contrasts upheld the significant association between breeding system and seed size among woody taxa, lianas, and all taxa pooled, but not among shrubs. We discuss the implications of our findings for evolutionary hypotheses regarding associations between dioecy and seed size.  相似文献   
345.
This paper includes the proposals made in the report “Basis for a National Strategy for Coastal Zone Management” prepared for the Portuguese Ministry of Environment, Territorial Planning and Regional Development. The final version of that report was presented in June 2006. This paper describes a theme framework followed by a discussion of concepts. Nine Primary Principles, eight Principal Objectives, and 37 Strategic Options for an Integrated Coastal Zone Management are then presented. These Strategic Options are set hierarchically according to their sequential priority, identifying the dominant types of Associated Measures. The analysis of these arrives at a set of Structural Measures, which interlink and aggregate various actions and propose a new method of integrated management for the coastal zone, which includes the “Legal Basis of Coastal Zone”; the Organization System; the Action Plan and Monitoring.  相似文献   
346.
Environmental Science and Pollution Research - Global consumption of synthetic dyes is roughly 7?×?105 tons per year, of which the textile industry expends about two-thirds....  相似文献   
347.
A greenhouse experiment was carried out in order to investigate the effects of arbuscular mycorrhizal (AM) fungi inoculation and the use of composted olive waste (COW) in the establishment of Tetraclinis articulata and soil properties in a heavy metal-polluted soil. The treatments assayed were as follows: AM?+?0 % COW, AM?+?1 % COW, and AM?+?3 % COW. The higher doses of COW in combination with AM fungi increased shoot and root biomass production of T. articulata by 96 and 60 %, respectively. These treatments trended to improve the soil properties evaluated, highlighting the C compounds and N as well as the microbiological activities. In relation to the metal translocation in T. articulata, doses of COW applied decreased the Cr, Ni, and Pb contents in shoot, as well as Cr and As in root, although the most of them reached low levels and far from phytotoxic. The COW amendment aided Glomus mosseae-inoculated T. articulata plants to thrive in contaminated soil, mainly through an improvement in both nutrients uptake, mainly P and soil microbial function. In addition, the combined use of AM fungi plus COW could be a feasible strategy to be incorporated in phytoremediation programs because it promotes soil properties, a better performance of plants for supporting the stress in heavy metal-contaminated soils derived from the mining process, and also can be a good way for olive-mill waste disposal.  相似文献   
348.
We determined the length, volume, dry biomass, and density in seeds of five castor bean cultivars and verified notable physicochemical trait differences. Seeds were then subjected to different toxic aluminum (Al) concentrations to evaluate germination, relative root elongation, and the role of root apices’ rhizosphere mucilage layer. Seeds’ physicochemical traits were associated with Al toxicity responses, and the absence of Al in cotyledons near to the embryo was revealed by Al-hematoxylin staining, indicating that Al did not induce significant germination reduction rates between cultivars. However, in the more sensitive cultivar, Al was found around the embryo, contributing to subsequent growth inhibition. After this, to investigate the role of mucilage in Al tolerance, an assay was conducted using NH4Cl to remove root mucilage before or after exposure to different Al concentrations. Sequentially, the roots were stained with hematoxylin and a quantitative analysis of staining intensity was obtained. These results revealed the significant contribution of the mucilage layer to Al toxicity responses in castor bean seedlings. Root growth elongation under Al toxicity confirmed the role of the mucilage layer, which jointly indicated the differential Al tolerance between cultivars and an efficient Al-exclusion mechanism in the tolerant cultivar.  相似文献   
349.
The need for understanding the factors that trigger human responses to climate change has opened inquiries on the role of indigenous and local ecological knowledge (ILK) in facilitating or constraining social adaptation processes. Answers to the question of how ILK is helping or limiting smallholders to cope with increasing disturbances to the local hydro-climatic regime remain very limited in adaptation and mitigation studies and interventions. Herein, we discuss a case study on ILK as a resource used by expert farmer-fishers (locally known as Caboclos) to cope with the increasing threats on their livelihoods and environments generated by changing flood patterns in the Amazon delta region. While expert farmer-fishers are increasingly exposed to shocks and stresses, their ILK plays a key role in mitigating impacts and in strengthening their adaptive responses that are leading to a process of incremental adaptation (PIA). We argue that ILK is the most valuable resource used by expert farmer-fishers to adapt the spatial configuration and composition of their land-/resource-use systems (agrodiversity) and their produced and managed resources (agrobiodiversity) at landscape, community and household levels. We based our findings on ILK on data recorded for over the last 30 years using detailed ethnographic methodologies and multitemporal landscape mapping. We found that the ILK of expert farmer-fishers and their “tradition of change” have facilitated the PIA to intensify a particular production system to optimize production across a broad range of flood conditions and at the same time to manage or conserve forests to produce resources and services.  相似文献   
350.
We present a synoptic, participatory vulnerability assessment tool to help identify the likely impacts of climate change and human activity in coastal areas and begin discussions among stakeholders on the coping and adaptation measures necessary to minimize these impacts. Vulnerability assessment tools are most needed in the tropical Indo-Pacific, where burgeoning populations and inequitable economic growth place even greater burdens on natural resources and support ecosystems. The Integrated Coastal Sensitivity, Exposure, and Adaptive Capacity for Climate Change (I-C-SEA Change) tool is built around a series of scoring rubrics to guide non-specialists in assigning scores to the sensitivity and adaptive capacity components of vulnerability, particularly for coral reef, seagrass, and mangrove habitats, along with fisheries and coastal integrity. These scores are then weighed against threat or exposure to climate-related impacts such as marine flooding and erosion. The tool provides opportunities for learning by engaging more stakeholders in participatory planning and group decision-making. It also allows for information to be collated and processed during a “town-hall” meeting, facilitating further discussion, data validation, and even interactive scenario building.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-015-0652-x) contains supplementary material, which is available to authorized users.  相似文献   
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