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11.
When approached by males, females of the Amarillo fish (Girardinichthys multiradiatus) perform a behaviour called vibration or they are aggressively challenged. We quantified vibration and assessed whether it compromises the rate of feeding attempts in dyads kept in outdoor enclosures. Male approaches resulted in female vibration and in a reduced feeding rate. Vibration was not evoked by female–female aggression, which was frequent and always ended in the subordinate fleeing from the dominant female. Using a closed respirometer we found that vibration is costly; oxygen consumption of females was greater in the presence of a male (which evoked vibration) than in the presence of a non-familiar female (when no vibration occurred). By recording interactions of females confined in aquaria in the presence and in the absence of males, we confirmed that escaping is the only available response to deal with female aggression. Females kept without males participated in frequent aggressive (even lethal) interactions that did not abate while the subordinate female was in sight of the dominant, and which caused premature births and injuries. Yet in the alternative treatment aggression ceased when a male approached, prompting vibration in both females. Thus, in the Amarillo, in as much as it evokes energetically costly female vibrations, male courtship is an expression of sexual conflict. However, in the absence of males, frequent female aggression potentially annuls the benefits of not vibrating. We propose that a complete appraisal of the consequences of sexual conflict must include an assessment of the costs imposed by intra-sexual interactions.  相似文献   
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Spontaneous combustion and low-temperature oxidation of waste coal and other carbonaceous material at open-cut coal mines are potentially significant sources of greenhouse gas emissions. However, the magnitude of these emissions is largely unknown. In this study, emissions from spontaneous combustion and low-temperature oxidation were estimated for six Australian open-cut coal mines with annual coal production ranging from 1.7 to more than 16 Mt. Greenhouse emissions from all other sources at these mines were also estimated and compared to those from spontaneous combustion and low-temperature oxidation. In all cases, fugitive emission of methane was the largest source of greenhouse gas; however, in some mines, spontaneous combustion accounted for almost a third of all emissions. For one mine, it was estimated that emissions from spontaneous combustion were around 250,000 t CO2-e per annum. The contribution from low-temperature oxidation was generally less than about 1% of the total for all six mines. Estimating areas of spoil affected by spontaneous combustion by ground-based surveys was prone to under-report the area. Airborne infrared imaging appears to be a more reliable method.  相似文献   
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The Arctic is nutrient limited, particularly by nitrogen, and is impacted by anthropogenic global warming which occurs approximately twice as fast compared to the global average. Arctic warming intensifies thawing of permafrost-affected soils releasing their large organic nitrogen reservoir. This organic nitrogen reaches hydrological systems, is remineralized to reactive inorganic nitrogen, and is transported to the Arctic Ocean via large rivers. We estimate the load of nitrogen supplied from terrestrial sources into the Arctic Ocean by sampling in the Lena River and its Delta. We took water samples along one of the major deltaic channels in winter and summer in 2019 and sampling station in the central delta over a one-year cycle. Additionally, we investigate the potential release of reactive nitrogen, including nitrous oxide from soils in the Delta. We found that the Lena transported nitrogen as dissolved organic nitrogen to the coastal Arctic Ocean and that eroded soils are sources of reactive inorganic nitrogen such as ammonium and nitrate. The Lena and the Deltaic region apparently are considerable sources of nitrogen to nearshore coastal zone. The potential higher availability of inorganic nitrogen might be a source to enhance nitrous oxide emissions from terrestrial and aquatic sources to the atmosphere.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01665-0.  相似文献   
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The need for mental health resources to provide care to the community following large‐scale disasters is well documented. In the aftermath of the World Trade Center (WTC) disaster on September 11, 2001, many local agencies and organizations responded by providing informal mental health services, including disaster mental health training for practitioners. The quality of these programmes has not been assessed, however. The National Center for Disaster Preparedness at Columbia University's School of Public Health reviewed disaster mental health training programmes administered by community‐based organizations, professional associations, hospitals, and government agencies after September 11. Results indicate that the quality and the effectiveness of programmes are difficult to assess. A wide range of curricula and a widespread lack of recordkeeping and credentialing of trainers were noted. Most of the training programmes provided are no longer available. Recommendations for improving the quality of disaster mental health training programmes are provided.  相似文献   
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Many vertebrates grow up in the company of same or different-age siblings, and relations among them can be expected to significantly influence individual life histories and the development of individual morphological, physiological, and behavioral phenotypes. Although studies in birds still dominate and have stimulated most theoretical considerations, the increasing number of mammalian studies promises to broaden our understanding of this complex field by enabling interesting comparisons with the rather different bird system. It therefore seems timely to bring together recent studies of sibling relations in mammals and to demonstrate what these can offer in the way of fresh insights. In this brief review, intended to accompany a series of papers on a diverse range of mammals, we outline the current state of sibling research in mammals, comparing it to the better studied birds. Most obviously, in mammals, mother and young are in much closer contact during early life than in birds, and siblings can influence each other’s development as well as the mother’s physiology while still in utero. During nursing, mammalian young also encounter a very different feeding situation to bird siblings. These contrasts should help stimulate further debate, as well as provide further opportunities to study the relative importance of maternal versus sibling effects on individual development. Finally, we discuss the need to balance studies of sibling competition and conflict with a consideration of the benefits accruing to individuals from sibling presence and the need for long-term studies of the influence of early sibling relations on individual development and life histories. This contribution represents the introduction to the special issue “Sibling competition and cooperation in mammals”.  相似文献   
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The Australian environment and agriculture is suffering from land degradation and declining biodiversity. Laws protecting native vegetation are aimed at addressing these problems but have been resisted by farmers, compromising the social agreement necessary for regulatory success. A case study drawing on farmer interviews in central northern New South Wales reveals that the laws are considered to be under-achieving environmental outcomes since they are ill-suited to local conditions. The low feasibility of the rules is also undermining rule and state legitimacy. Regulatory resistance is due to the lack of recognition of place-specifics by government and laws that impose universal requirements. There is an epistemic distance between the bureaucratic knowledge held by government and the vernacular knowledge (place-based knowledge) of heterogeneous environments held by farmers. Incorporating vernacular knowledge so that laws are more geographically sympathetic may close vernacular disjunctures and cure regulatory failure.  相似文献   
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China has made some remarkable achievements in sustainable development,but the constant deterioration of the overall trend of the environment has not yet been effectively curbed.To achieve the goal of sustainable development,we must first ensure coordination and coherence of national development goals in different areas and adhere to green development road.To achieve the objectives related to green development,and to clarify the direction of green development in the next 20years,a road map is needed to guide and coordinate the process.This paper describes the concept of the green development road map,introduces a green development road map for the western region,and further elaborates it The road map clarifies the objectives and guiding principles of green development in the western region,points the areas that deserve more concern and institutional innovation,and builds a green development monitoring and evaluation(M&E)framework.Finally,the paper provides corresponding policy recommendations based on the established road map.  相似文献   
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