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111.
MarÍA JOSÉ Ruiz‐López Natalia Gañan José Antonio Godoy Ana Del Olmo Julian Garde Gerardo Espeso Astrid Vargas Fernando Martinez Eduardo R. S. Roldán Montserrat Gomendio 《Conservation biology》2012,26(6):1121-1129
The relation among inbreeding, heterozygosity, and fitness has been studied primarily among outbred populations, and little is known about these phenomena in endangered populations. Most researchers conclude that the relation between coefficient of inbreeding estimated from pedigrees and fitness traits (inbreeding‐fitness correlations) better reflects inbreeding depression than the relation between marker heterozygosity and fitness traits (heterozygosity‐fitness correlations). However, it has been suggested recently that heterozygosity‐fitness correlations should only be expected when inbreeding generates extensive identity disequilibrium (correlations in heterozygosity and homozygosity across loci throughout the genome). We tested this hypothesis in Mohor gazelle (Gazella dama mhorr) and Iberian lynx (Lynx pardinus). For Mohor gazelle, we calculated the inbreeding coefficient and measured heterozygosity at 17 microsatellite loci. For Iberian lynx, we measured heterozygosity at 36 microsatellite loci. In both species we estimated semen quality, a phenotypic trait directly related to fitness that is controlled by many loci and is affected by inbreeding depression. Both species showed evidence of extensive identity disequilibrium, and in both species heterozygosity was associated with semen quality. In the Iberian lynx the low proportion of normal sperm associated with low levels of heterozygosity was so extreme that it is likely to limit the fertility of males. In Mohor gazelle, although heterozygosity was associated with semen quality, inbreeding coefficient was not. This result suggests that when coefficient of inbreeding is calculated on the basis of a genealogy that begins after a long history of inbreeding, the coefficient of inbreeding fails to capture previous demographic information because it is a poor estimator of accumulated individual inbreeding. We conclude that among highly endangered species with extensive identity disequilibrium, examination of heterozygosity‐fitness correlations may be an effective way to detect inbreeding depression, whereas inbreeding‐fitness correlations may be poor indicators of inbreeding depression if the pedigree does not accurately reflect the history of inbreeding. Correlaciones Heterocigosidad‐ Adaptabilidad y Depresión Endogámica en Dos Especies de Mamíferos Críticamente en Peligro 相似文献
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113.
Nazario D. Ramírez‐Beltran Joan Manuel Castro Eric Harmsen Ramón Vásquez 《Journal of the American Water Resources Association》2008,44(4):847-865
Abstract: A practical methodology is proposed to estimate the three‐dimensional variability of soil moisture based on a stochastic transfer function model, which is an approximation of the Richard’s equation. Satellite, radar and in situ observations are the major sources of information to develop a model that represents the dynamic water content in the soil. The soil‐moisture observations were collected from 17 stations located in Puerto Rico (PR), and a sequential quadratic programming algorithm was used to estimate the parameters of the transfer function (TF) at each station. Soil texture information, terrain elevation, vegetation index, surface temperature, and accumulated rainfall for every grid cell were input into a self‐organized artificial neural network to identify similarities on terrain spatial variability and to determine the TF that best resembles the properties of a particular grid point. Soil moisture observed at 20 cm depth, soil texture, and cumulative rainfall were also used to train a feedforward artificial neural network to estimate soil moisture at 5, 10, 50, and 100 cm depth. A validation procedure was implemented to measure the horizontal and vertical estimation accuracy of soil moisture. Validation results from spatial and temporal variation of volumetric water content (vwc) showed that the proposed algorithm estimated soil moisture with a root mean squared error (RMSE) of 2.31% vwc, and the vertical profile shows a RMSE of 2.50% vwc. The algorithm estimates soil moisture in an hourly basis at 1 km spatial resolution, and up to 1 m depth, and was successfully applied under PR climate conditions. 相似文献
114.
Employment liability is an important check and balance against employee harm at work. In practice, however, an inadvertent consequence of employment liability is a potential shift in power from organizations to employees that affects subsequent managerial decision making. In this Incubator, we discuss behavioral and attitudinal ramifications of employment liability at work. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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116.
A Modeling System to Assess Land Cover Land Use Change Effects on SAV Habitat in the Mobile Bay Estuary 下载免费PDF全文
Maurice G. Estes Jr. Mohammad Z. Al‐Hamdan Jean T. Ellis Chaeli Judd Dana Woodruff Ronald M. Thom Dale Quattrochi Brian Watson Hugo Rodriguez Hoyt Johnson III Tom Herder 《Journal of the American Water Resources Association》2015,51(2):513-536
Estuarine ecosystems are largely influenced by watersheds directly connected to them. In the Mobile Bay, Alabama watersheds we examined the effect of land cover and land use (LCLU) changes on discharge rate, water properties, and submerged aquatic vegetation, including freshwater macrophytes and seagrasses, throughout the estuary. LCLU scenarios from 1948, 1992, 2001, and 2030 were used to influence watershed and hydrodynamic models and evaluate the impact of LCLU change on shallow aquatic ecosystems. Overall, our modeling results found that LCLU changes increased freshwater flows into Mobile Bay altering temperature, salinity, and total suspended sediments (TSS). Increased urban land uses coupled with decreased agricultural/pasture lands reduced TSS in the water column. However, increased urbanization or agricultural/pasture land coupled with decreased forest land resulted in higher TSS concentrations. Higher sediment loads were usually strongly correlated with higher TSS levels, except in areas where a large extent of wetlands retained sediment discharged during rainfall events. The modeling results indicated improved water clarity in the shallow aquatic regions of Mississippi Sound and degraded water clarity in the Wolf Bay estuary. This integrated modeling approach will provide new knowledge and tools for coastal resource managers to manage shallow aquatic habitats that provide critical ecosystem services. 相似文献
117.
Jinxue Luo Jinsong Zhang Xiaohui Tan Diane McDougald Guoqiang Zhuang Anthony G.Fane Staffan Kjelleberg Yehuda Cohen Scott A.Rice 《环境科学学报(英文版)》2015,(3):115-123
Biofilm formation, one of the primary causes of biofouling, results in reduced membrane flux or increased transmembrane pressure and thus represents a major impediment to the wider implementation of membrane bioreactor(MBR) technologies for water purification. Most studies have focused on the role of bacteria in membrane fouling as they are the most dominant and best studied organisms present in the MBR. In contrast, there is limited information on the role of the archaeal community in biofilm formation in MBRs. This study investigated the composition of the archaeal community during the process of biofouling in an MBR. The archaeal community was observed to have lower richness and diversity in the biofilm than the sludge during the establishment of biofilms at low transmembrane pressure(TMP). Clustering of the communities based on the Bray–Curtis similarity matrix indicated that a subset of the sludge archaeal community formed the initial biofilms. The archaeal community in the biofilm was mainly composed of Thermoprotei, Thermoplasmata,Thermococci, Methanopyri, Methanomicrobia and Halobacteria. Among them, the Thermoprotei and Thermoplasmata were present at higher relative proportions in the biofilms than they were in the sludge. Additionally, the Thermoprotei, Thermoplasmata and Thermococci were the dominant organisms detected in the initial biofilms at low TMP, while as the TMP increased, the Methanopyri, Methanomicrobia, Aciduliprofundum and Halobacteria were present at higher abundances in the biofilms at high TMP. 相似文献
118.
Jacob Heilmann‐Clausen Elizabeth S. Barron Lynne Boddy Anders Dahlberg Gareth W. Griffith Jenni Nordén Otso Ovaskainen Claudia Perini Beatrice Senn‐Irlet Panu Halme 《Conservation biology》2015,29(1):61-68
Hitherto fungi have rarely been considered in conservation biology, but this is changing as the field moves from addressing single species issues to an integrative ecosystem‐based approach. The current emphasis on biodiversity as a provider of ecosystem services throws the spotlight on the vast diversity of fungi, their crucial roles in terrestrial ecosystems, and the benefits of considering fungi in concert with animals and plants. We reviewed the role of fungi in ecosystems and composed an overview of the current state of conservation of fungi. There are 5 areas in which fungi can be readily integrated into conservation: as providers of habitats and processes important for other organisms; as indicators of desired or undesired trends in ecosystem functioning; as indicators of habitats of conservation value; as providers of powerful links between human societies and the natural world because of their value as food, medicine, and biotechnological tools; and as sources of novel tools and approaches for conservation of megadiverse organism groups. We hope conservation professionals will value the potential of fungi, engage mycologists in their work, and appreciate the crucial role of fungi in nature. Una Perspectiva Micótica de la Biología de la Conservación 相似文献
119.
Impact of payments for environmental services and protected areas on local livelihoods and forest conservation in northern Cambodia 总被引:1,自引:0,他引:1 下载免费PDF全文
The potential impacts of payments for environmental services (PES) and protected areas (PAs) on environmental outcomes and local livelihoods in developing countries are contentious and have been widely debated. The available evidence is sparse, with few rigorous evaluations of the environmental and social impacts of PAs and particularly of PES. We measured the impacts on forests and human well‐being of three different PES programs instituted within two PAs in northern Cambodia, using a panel of intervention villages and matched controls. Both PES and PAs delivered additional environmental outcomes relative to the counterfactual: reducing deforestation rates significantly relative to controls. PAs increased security of access to land and forest resources for local households, benefiting forest resource users but restricting households’ ability to expand and diversify their agriculture. The impacts of PES on household well‐being were related to the magnitude of the payments provided. The two higher paying market‐linked PES programs had significant positive impacts, whereas a lower paying program that targeted biodiversity protection had no detectable effect on livelihoods, despite its positive environmental outcomes. Households that signed up for the higher paying PES programs, however, typically needed more capital assets; hence, they were less poor and more food secure than other villagers. Therefore, whereas the impacts of PAs on household well‐being were limited overall and varied between livelihood strategies, the PES programs had significant positive impacts on livelihoods for those that could afford to participate. Our results are consistent with theories that PES, when designed appropriately, can be a powerful new tool for delivering conservation goals whilst benefiting local people. 相似文献
120.
Immediate behavioural responses to earthquakes in Christchurch,New Zealand,and Hitachi,Japan 总被引:1,自引:0,他引:1 下载免费PDF全文
Michael K. Lindell Carla S. Prater Hao Che Wu Shih‐Kai Huang David M. Johnston Julia S. Becker Hideyuki Shiroshita 《Disasters》2016,40(1):85-111
This study examines people's immediate responses to earthquakes in Christchurch, New Zealand, and Hitachi, Japan. Data collected from 257 respondents in Christchurch and 332 respondents in Hitachi revealed notable similarities between the two cities in people's emotional reactions, risk perceptions, and immediate protective actions during the events. Respondents' physical, household, and social contexts were quite similar, but Hitachi residents reported somewhat higher levels of emotional reaction and risk perception than did Christchurch residents. Contrary to the recommendations of emergency officials, the most frequent response of residents in both cities was to freeze. Christchurch residents were more likely than Hitachi residents to drop to the ground and take cover, whereas Hitachi residents were more likely than Christchurch residents to evacuate immediately the building in which they were situated. There were relatively small correlations between immediate behavioural responses and demographic characteristics, earthquake experience, and physical, social, or household context. 相似文献