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151.
皮氏菊头蝠(Rhinolophus pearsoni)是我国南方典型的洞栖食虫性蝙蝠,具有重要的生态意义。近年于湘西州及张家界市的25个溶洞中共记录到该蝠450只次,对其栖息生态特征(空间分布、姿势、体温、栖点温度和栖点安全性等)进行了较为系统的观测。结果表明:该蝠的栖点主要集中分布于离洞口440 m之内的洞段(占99.3%),栖点高度通常介于2—10 m之间(84%),主要采取双足倒挂的姿势栖息于洞顶壁或侧壁,但单足倒挂的栖息姿势也较为常见(36.2%)。体温介于10.7—25.2℃,体温总是稍高于栖点温度,但两者之间无显著性差异(P0.05),且两者呈线性正相关。约64%的栖点"安全性高",而"安全性低"和"安全性中"的栖点分别占17.6%和18.4%。减少对洞穴的人为干扰是保护该物种的有效途径。 相似文献
152.
Wesley W. Ingwersen 《Journal of Industrial Ecology》2011,15(4):550-567
Founded in thermodynamics and systems ecology, emergy evaluation is a method to associate a product with its dependencies on all upstream environmental and resource flows using a common unit of energy. Emergy is thus proposed as an indicator of aggregate resource use for life cycle assessment (LCA). An LCA of gold mining, based on an original life cycle inventory of a large gold mine in Peru, is used to demonstrate how emergy can be incorporated as an impact indicator into a process‐based LCA model. The results demonstrate the usefulness of emergy in the LCA context. The adaptation of emergy evaluation, traditionally performed outside of the LCA framework, requires changes to the conventional accounting rules and the incorporation of uncertainty estimations of the emergy conversion factors, or unit emergy values. At the same time, traditional LCA boundaries are extended to incorporate the environmental processes that provide for raw resources, including ores. The total environmental contribution to the product, doré, is dominated by mining and metallurgical processes and not the geological processes forming the gold ore. The measure of environmental contribution to 1 gram (g) of doré is 6.8E + 12 solar‐equivalent Joules (sej) and can be considered accurate within a factor of 2. These results are useful in assessing a process in light of available resources, which is essential to measuring long‐term sustainability. Comparisons are made between emergy and other measures of resource use, and recommendations are made for future incorporation of emergy into LCA that will result in greater consistency with existing life cycle inventory (LCI) databases and other LCA indicators. 相似文献
153.
Pere Fullana i Palmer Rita Puig Alba Bala Grau Baquero Jordi Riba Marco Raugei 《Journal of Industrial Ecology》2011,15(3):458-475
Life cycle assessment (LCA) is a widely accepted methodology to support decision‐making processes in which one compares alternatives, and that helps prevent shifting of environmental burdens along the value chain or among impact categories. According to regulation in the European Union (EU), the movement of waste needs to be reduced and, if unavoidable, the environmental gain from a specific waste treatment option requiring transport must be larger than the losses arising from transport. The EU explicitly recommends the use of LCA or life cycle thinking for the formulation of new waste management plans. In the last two revisions of the Industrial Waste Management Programme of Catalonia (PROGRIC), the use of a life cycle thinking approach to waste policy was mandated. In this article we explain the process developed to arrive at practical life cycle management (LCM) from what started as an LCA project. LCM principles we have labeled the “3/3” principle or the “good enough is best” principle were found to be essential to obtain simplified models that are easy to understand for legislators and industries, useful in waste management regulation, and, ultimately, feasible. In this article, we present the four models of options for the management of waste solvent to be addressed under Catalan industrial waste management regulation. All involved actors concluded that the models are sufficiently robust, are easy to apply, and accomplish the aim of limiting the transport of waste outside Catalonia, according to the principles of proximity and sufficiency. 相似文献
154.
Anna Hillbricht-Ilkowska 《Hydrobiologia》1993,251(1-3):257-268
Two river-lake systems in a mosaic, lowland postglacial landscape (Masurian and Suwalskie Lakelands, northeastern Poland) of different length and flow were studied. The concentration of total and dissolved phosphorus (in water and in seston) and the retention of these two forms of P were analysed at several hydrological occasions in lakes of various morphometry and trophy, and in several stream fragments. The concentration and retention is equally highly variable in lake (lentic patches) and stream fragments (lotic patches) of the system. The polluted stream fragments at all occassions as well as the lakes in summer, are mainly exporting phoshorus. The patches which act as sources occur alternatively with patches which are P-sinks. This makes the whole system more or less balanced with respect to P movement in the landscape. 相似文献
155.
MANUEL B. CRESPO LUIS SERRA 《Botanical journal of the Linnean Society. Linnean Society of London》1993,111(1):37-46
The name Ononis rentonarensis is proposed for a new Spanish species belonging to Ononis section Matrix subsection Rhodanlhae, whose distribution is restricted to a few localities in northeastern Alicante Province (E.Spain). Its morphological features, ecology and main relationships and differences with other Spanish species in the subsection are discussed. 相似文献
156.
Shannon M. Beston Jeffry L. Dudycha David M. Post Matthew R. Walsh 《Evolution; international journal of organic evolution》2019,73(4):792-802
Variation in eye size is ubiquitous across taxa. Increased eye size is correlated with improved vision and increased fitness via shifts in behavior. Tests of the drivers of eye size evolution have focused on macroevolutionary studies evaluating the importance of light availability. Predator‐induced mortality has recently been identified as a potential driver of eye size variation. Here, we tested the influence of increased predation by the fish predator, the alewife (Alosa pseudoharengus) on eye size evolution in waterfleas (Daphnia ambigua) from lakes in Connecticut. We quantified the relative eye size of Daphnia from lakes with and without alewife using wild‐caught and third‐generation laboratory reared specimens. This includes comparisons between lakes where alewife are present seasonally (anadromous) or permanently (landlocked). Wild‐caught specimens did not differ in eye size across all lakes. However, third‐generation lab reared Daphnia from lakes with alewife, irrespective of the form of alewife predation, exhibited significantly larger eyes than Daphnia from lakes without alewife. This genetically based increase in eye size may enhance the ability of Daphnia to detect predators. Alternatively, such shifts in eye size may be an indirect response to Daphnia aggregating at the bottom of lakes. To test these mechanisms, we collected Daphnia as a function of depth and found that eye size differed in Daphnia found at the surface versus the bottom of the water column between anadromous alewife and no alewife lakes. However, we found no evidence of Daphnia aggregating at the bottom of lakes. Such results indicate that the evolution of a larger eye may be explained by a connection between eyes and enhanced survival. We discuss the cause of the lack of concordance in eye size variation between our phenotypic and genetic specimens and the ultimate drivers of eye size. 相似文献
157.
Jeremy M. Cohen David J. Civitello Matthew D. Venesky Taegan A. McMahon Jason R. Rohr 《Global Change Biology》2019,25(3):927-937
Climate change might drive species declines by altering species interactions, such as host–parasite interactions. However, few studies have combined experiments, field data, and historical climate records to provide evidence that an interaction between climate change and disease caused any host declines. A recently proposed hypothesis, the thermal mismatch hypothesis, could identify host species that are vulnerable to disease under climate change because it predicts that cool‐ and warm‐adapted hosts should be vulnerable to disease at unusually warm and cool temperatures, respectively. Here, we conduct experiments on Atelopus zeteki, a critically endangered, captively bred frog that prefers relatively cool temperatures, and show that frogs have high pathogen loads and high mortality rates only when exposed to a combination of the pathogenic chytrid fungus (Batrachochytrium dendrobatidis) and high temperatures, as predicted by the thermal mismatch hypothesis. Further, we tested various hypotheses to explain recent declines experienced by species in the amphibian genus Atelopus that are thought to be associated with B. dendrobatidis and reveal that these declines are best explained by the thermal mismatch hypothesis. As in our experiments, only the combination of rapid increases in temperature and infectious disease could account for the patterns of declines, especially in species adapted to relatively cool environments. After combining experiments on declining hosts with spatiotemporal patterns in the field, our findings are consistent with the hypothesis that widespread species declines, including possible extinctions, have been driven by an interaction between increasing temperatures and infectious disease. Moreover, our findings suggest that hosts adapted to relatively cool conditions will be most vulnerable to the combination of increases in mean temperature and emerging infectious diseases. 相似文献
158.
Georg Schiller Alessio Miatto Karin Gruhler Regine Ortlepp Clemens Deilmann Hiroki Tanikawa 《Journal of Industrial Ecology》2019,23(4):796-807
Most anthropogenic material stocks and flows are associated with the building sector. Several recent studies have developed material composition indicators (MCIs) suitable for calculating material stocks and flows of the building sector using bottom‐up approaches, which hold great potential to provide information to support resource efficiency policies. A major limitation is the lack of country‐specific MCIs. This study aims to introduce a concept for a better transferability of MCI across different contexts by proposing requirements for defining MCIs and to discuss options and limits of the transferability. We take existing MCIs for residential buildings in Germany and Japan as case studies and make them comparable by applying harmonization methods. Based on that, similarities and differences are systematically identified and discussed, considering their socioeconomic, cultural, technical, and environmental factors. Our results indicate significant limitations to the transferability of MCIs for detached houses, while bigger apartment complexes show greater homogeneity despite the very different environments in which they are constructed. This indicates that while it is possible to assume foreign MCIs as plausible for large constructions, local coefficients need to be estimated for smaller single‐family homes. 相似文献
159.
2012年和2013年4~8月,在贵州贵定县境内采用定点观察法对黄喉鹀(Emberiza elegans)的繁殖行为进行了初步观察,并测量了雏鸟的体重和体长,第5飞羽、尾长、嘴峰长、跗跖等生长情况,用Logistic方程对体重和体长进行拟合。黄喉鹀常常结成小群活动于山间溪流平缓处的阔叶林间以及山间的草甸和灌丛,极少活动于针叶林带。其种群遇见率为3.13只/km,种群密度为7.82只/km2。繁殖期是4~7月份。共发现17巢,地面巢11个,树上巢6个。营巢期6~8 d(n=9),巢分为外中内3层。巢外径(10.8±0.6)cm×(10.7±0.7)cm,内径(7.2±0.3)cm×(7.0±0.4)cm,巢深(6.1±0.4)cm,巢高(7.4±0.2)cm。卵有褐色斑点,卵重(2.20±0.01)g,卵长径(18.34±0.45)mm,卵短径(15.03±0.05)mm。窝卵数(3.6±0.4)枚(3~6枚)(n=9)。对2巢亲鸟(2♀,2♂)13 d白天坐巢时间统计,雌鸟坐巢时间9.69 h/d,雄鸟3.49 h/d。孵卵期12~14 d(n=8),孵化率84.37%。雏鸟留巢11~12 d(n=6),雏鸟离巢率74.07%。雏鸟的外部器官的生长发育符合雀形目外部器官发育规律。体重和体长生长的Logistic拟合方程分别为W=18.03/1+e3.06-0.27t和L=15.60/1+e1.21-0.17t。 相似文献
160.
Seppo Rytknen Eero J. Vesterinen Coen Westerduin Tiina Levikangas Emma Vatka Marko Mutanen Panu Vlimki Markku Hukkanen Marko Suokas Markku Orell 《Ecology and evolution》2019,9(1):631-639
Diets play a key role in understanding trophic interactions. Knowing the actual structure of food webs contributes greatly to our understanding of biodiversity and ecosystem functioning. The research of prey preferences of different predators requires knowledge not only of the prey consumed, but also of what is available. In this study, we applied DNA metabarcoding to analyze the diet of 4 bird species (willow tits Poecile montanus, Siberian tits Poecile cinctus, great tits Parus major and blue tits Cyanistes caeruleus) by using the feces of nestlings. The availability of their assumed prey (Lepidoptera) was determined from feces of larvae (frass) collected from the main foraging habitat, birch (Betula spp.) canopy. We identified 53 prey species from the nestling feces, of which 11 (21%) were also detected from the frass samples (eight lepidopterans). Approximately 80% of identified prey species in the nestling feces represented lepidopterans, which is in line with the earlier studies on the parids' diet. A subsequent laboratory experiment showed a threshold for fecal sample size and the barcoding success, suggesting that the smallest frass samples do not contain enough larval DNA to be detected by high‐throughput sequencing. To summarize, we apply metabarcoding for the first time in a combined approach to identify available prey (through frass) and consumed prey (via nestling feces), expanding the scope and precision for future dietary studies on insectivorous birds. 相似文献