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Long-term changes in the plant ecology of an african savanna landscape and the implications for ecosystem theory and conservation management

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Ecological Processes 2021年第1期10卷 213-224页

作者： David Western Victor N.Mose David Maitumo Caroline Mburu african conservation centre P.O.Box 15289-00509NairobiKeny

Background:Studies of the african savannas have used national parks to test ecological theories of natural ecosystems,including equilibrium,non-equilibrium,complex adaptive systems,and the role of top-down and bottom-up physical and biotic *** such studies have excluded the impact of pastoralists in shaping grassland ecosystems and,over the last half century,the growing human impact on the world’s *** mounting human impact calls for selecting indicators and integrated monitoring methods able to track ecosystem changes and the role of natural and human *** study draws on five decades of monitoring the Amboseli landscape in southern Kenya to document the declining role of natural agencies in shaping plant ecology with rising human ***:We show that plant diversity and productivity have declined,biomass turnover has increased in response to a downsizing of mean plant size,and that ecological resilience has declined with the rising probability of extreme shortfalls in pasture *** signature of rainfall and physical agencies in driving ecosystem properties has decreased sharply with growing human *** compare the Amboseli findings to the long-term studies of Kruger and Serengeti national parks to show that the human influence,whether by design or default,is increasingly shaping the ecology of savanna *** look at the findings in the larger perspective of human impact on african grasslands and the world rangelands,in general,and discuss the implications for ecosystem theory and conservation policy and ***:The Amboseli study shows the value of using long-term integrated ecological monitoring to track the spatial and temporal changes in the species composition,structure,and function of rangeland ecosystems and the role of natural and human agencies in the process of *** study echoes the widespread changes underway across african savannas and world’s rangelands,concluding that some level

关键词： Savannas Plants Human dominance Macroecology conservation

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Does the scent of a potential mate prevent the resorption of oocytes by apoptosis in Nauphoeta cinerea？

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Insect Science 2009年第5期16卷 393-398页

作者： Emma L. B. Barrett Allen J. Moore Patricia J. Moore centre for ecology and conservation School of Biosciences University of Exeter Cornwall Campus Penryn Cornwall UK

We expect organisms to have evolved mechanisms to gather and use the information available within their environments, to steer resource investment decisions toward the traits that will give the greatest fitness returns. Pheromones are social signals, a common purpose of which is to act as indicators of mate presence. Consequently, pheromones have the potential to act as signals to increase or maintain reproductive investment over that of competing life-history traits. In the cockroach, Nauphoeta cinerea （Oliver）, females pay costs of maintaining investment in reproduction when there are no males, and males produce pheromones that are known to effect female reproductive outcomes. Whether the pheromones have an influence on resource physiology is unknown. We subjected newly eclosed females to either a synthetic blend of male pheromones or control. We dissected females at 7, 12, 17 or 22 days. We measured apoptosis levels and size of all oocytes within the vitellerium, and measured dry fat body mass. Synthetic male pheromone blend did not have an effect on any measure of female reproductive or somatic resource physiology. Although negative results are always problematic, the success of the synthetic pheromone method in the past suggests that females may be insensitive to male pheromones in the pre-oviposition period, and may rely on mating stimulus rather than pheromone as the cue for oocyte maintenance and growth. Previous studies reporting effects of male pheromones on female reproduction suggest that the period of pheromone sensitivity may be between mating and birth.

关键词： apoptosis environment oocyte ovary pheromone predictable trade-off

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Molecular evolution and deorphanization of bitter taste receptors in a vampire bat

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Integrative Zoology 2021年第5期16卷 659-669页

作者： Qin LU Hengwu JIAO Yi WANG Ngawang NORBU Huabin ZHAO Department of ecology Tibetan Centre for Ecology and Conservation at WHU-TUHubei Key Laboratory of Cell HomeostasisCollege of Life SciencesWuhan UniversityWuhanChina Research Center for ecology College of ScienceTibet UniversityLhasaChina

Bats represent the largest dietary radiation in a single mammalian order,and have become an emerging model group for studying dietary *** receptor genes have proven to be molecular signatures of dietary diversification in *** example,all 3 extant species of vampire bats have lost many bitter taste receptor genes(Tas2rs)in association with their dietary shift from insectivory to ***,only 8 full-length Tas2rs were identified from the high-quality genome of the common vampire bat(Desmodus rotundus).However,it is presently unknown whether these bitter receptors are functional,since the sense of taste is less important in vampire bats,which have an extremely narrow diet and rely on other senses for acquiring ***,we applied a molecular evolutionary analysis of Tas2rs in the common vampire bat compared with non-vampire ***,we provided the first attempt to deorphanize all bitter receptors of the vampire bat using a cell-based *** found that all Tas2r genes in the vampire bat have a level of selective pressure similar to that in non-vampire bats,suggesting that this species must have retained some bitter taste *** demonstrated that 5 of the 8 bitter receptors in the vampire bat can be activated by some bitter compounds,and observed that the vampire bat generally can not detect naturally occurring bitter compounds examined in this *** study demonstrates functional retention of bitter taste in vampire bats as suggested by cell-based functional assays,calling for an in-depth study of extra-oral functions of bitter taste receptors.

关键词： bitter taste diet evolution selection vampire bat

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Genomic analysis of Tibetan ground tits identifies molecular adaptations associated with cooperative breeding

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Current Zoology 2023年第5期69卷 620-630页

作者： Yi Wang Chen Wang Wei Hong Shilin Tian Qin Lu Bing-Jun Wang Huaiming Jin Nima Zhuoma Xin Lu Huabin Zhao Department of ecology Tibetan Centre for Ecology and Conservation at Wuhan University—Tibet UniversityHubei Key Laboratory of Cell HomeostasisCollege of Life SciencesWuhan UniversityWuhan 430072China Research Center for ecology College of ScienceTibet UniversityLhasa 850000China

Cooperative breeding is a sophisticated altruistic social behavior that helps social animals to adapt to harsh *** Tibetan ground tit,Pseudopodoces humilis,is a high-altitude bird endemic to the Tibetan ***,it has become an exciting system for studying the evolution of facultative cooperative *** test for molecular adaptations associated with cooperative breeding,we resequenced the whole genome of ground tits from 6 wild populations that display remarkable variation in the frequency of cooperative *** structure analyses showed that the 6 populations were divided into 4 lineages,which is congruent with the major geographical distribution of the sampling *** genome-wide selective sweep analysis,we identified putative positively selected genes(PSGs)in groups of tits that displayed high and low cooperative breeding *** total number of PSGs varied from 146 to 722 in high cooperative breeding rate populations,and from 272 to 752 in low cooperative breeding rate *** enrichment analysis of these PSGs identified several significantly enriched ontologies related to oxytocin signaling,estrogen signaling,and insulin *** involved in these functional ontologies suggest that molecular adaptations in hormonal regulation may have played important roles in shaping the evolution of cooperative breeding in the ground *** together,our study provides candidate genes and functional ontologies involved in molecular adaptations associated with cooperative breeding in Tibetan ground tits,and calls for a better understanding of the genetic roles in the evolution of cooperative breeding.

关键词： cooperative breeding ground tit population genomics social behavior

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Using FTIR spectroscopy to detect sericin on historic silk

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Science China Chemistry 2010年第3期53卷 625-630页

作者： WYETH Paul Textile conservation centre University of Southampton Winchester Campus

Silks represent some of the most precious ancient and historic textile artefacts in collections *** optimum preservation demands an appreciation of their *** important concern,especially with regard to ancient Chinese silks,is whether the fabrics have been *** with remnant sericin gum coating the fibroin fibres would require different conservation *** previous research on aged silks,the presence of sericin has been inferred from amino acid analysis of *** the study reported here,the potential of FTIR spectroscopy to provide a simpler and rapid method of detecting sericin on silk has been *** fibroin and sericin exhibit singular IR *** total reflectance spectroscopy was found to highlight the sericin coating more effectively than transmission and reflectance *** particular peak intensity ratios were identified which might provide a quantitative estimate of the sericin content of new silk,to a sensitivity of 1%-2%.These were also shown to be valid indicators for the presence of sericin on artificially aged and archaeological silks,although quantitation was now not *** the peak intensity ratios,two signature peaks were also seen to be useful markers for silk fibroin,and their presence in a spectrum could be used to infer a degummed silk.

关键词： infrared spectroscopy attenuated total reflectance spectroscopy historic silk

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Brown planthopper Nilaparvata lugens was concentrated at the rear of the typhoon Soudelor in Eastern China in August 2015

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Insect Science 2018年第5期25卷 916-926页

作者： Jian Ma Ye-Chen Wang Yan-Yue Hu Ming-Hong Lu Gui-Jun Wan Fa-Jun Chen Wan-Cai Liu Bao-Ping Zhai Gao Hu College of Plant Protection Nanjing Agricultural University Nanjing China Division of Pest Forecasting China National Agro-Tec Extension and Service Centre Beijing China centre for ecology and conservation University of Exeter Penryn Cornwall UK

Sometimes, extreme weather is vital for the population survival of migratory insects by causing sudden population collapse or outbreak. Several studies have shown that rice planthopper migration was significantly influenced by typhoons in eastern Asia. Most typhoons occur in the summer, especially in August. In August, brown planthopper Nilaparvata lugens （Stal） migrates northward or southward depending on wind direc- tion, and thus typhoons can potentially influence its migration process and population distribution. However, this has not yet been studied. This paper reported a case study on the effects of Typhoon Soudelor on the summer migration of N. lugens in eastern China in 2015. The migration pathways of N. lugens were reconstructed for the period under the influence of a typhoon by calculating the trajectories and migration events in eight counties of the Yangtze River Valley region with ancillary information. Trajectory mod- elling showed that most migrants took short distance migrations （less than 200 km） under the influence of the Typhoon Soudelor. Numerous N. lugens migrants were concentrated and deposited at the rear of the typhoon during the last 5 days of Typhoon Soudelor on August 9-13 due to horizontal convergence, and this led to an outbreak population. These results indicated that the N. lugens population was redistributed by the typhoon in the sum- mer and that the population dynamics at the rear of a typhoon should be kept under close surveillance. This study provided insight into migratory organisms adapting to atmospheric features.

关键词： insect migration Nilaparvata lugens trajectory analysis typhoon WRFModel

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Anti-Predator Coloration and Behaviour： A Longstanding Topic with Many Outstanding Questions

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Current Zoology 2015年第4期61卷 702-707页

作者： Martin STEVENS centre for ecology & conservation College of Life & Environmental Sciences University of Exeter Penryn Campus Penryn Cornwall TR10 9FE UK

1 Introduction The study of anti-predator coloration and behaviour has a long and rich history in biology. It has from the very outset of Darwin＇s theory of natural selection provided numerous areas to test mechanisms and function in evolution. While Darwin perhaps concentrated most of his attention regarding animal coloration on his theory of sexual selection （Darwin, 1871）, his contem- poraries placed much greater emphasis and time to explain the variety of ways that coloration and behaviour protected animals from attack from predators.

关键词：反捕食行为自然选择理论色彩保护动物达尔文着色生物学

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Investigating climate change vulnerability and planning for adaptation: Learning from a study of climate change impacts on the Mountain Gorilla in the Albertine Rift

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Natural Science 2013年第5期5卷 10-17页

作者： Daniel John McGahey David Gerard Williams Philip Muruth David Ian Loubser african Wildlife Foundation AWF Conservation Centre Nairobi Kenya african Wildlife Foundation AWF Conservation Centre Nairobi Kenya

Climate change represents an unprecedented challenge for the conservation and management of endangered species and habitats. Effective climate smart conservation will require robust predictions of vulnerability and future changes, along with the design and prioritisation of effective adaptation planning and management responses that are clearly linked to projected climate impacts. To achieve this goal, conservation managers urgently need practical tools and approaches for vulnerability assessment and adaptation planning. This article explores lessons emerging from a recent vulnerability assessment and adaptation planning exercise conducted on the impact of climate change for mountain gorilla (Gorilla beringei beringei). We describe the main findings emerging from this initiative and explore key lessons for climate change vulnerability assessment and adaptation planning for conservation management. Data limitations were a key factor determining the utility of model outputs and we stress the importance of stakeholder engagement and collaboration throughout the vulnerability assessment and adaptation planning cycle. These findings are of relevance to conservation practitioners seeking to incurporate climate change considerations into ongoing management planning for endangered species conservation.

关键词： conservation Planning Endangered Species Mountain Gorilla Climate Change Adaptation Vulnerability Assessment

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Effect of Vachellia tortilis on understory vegetation,herbaceous biomass and soil nutrients along a grazing gradient in a semi-arid african savanna

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Journal of Forestry Research 2018年第6期29卷 1601-1609页

作者： Temesgen Yadeta Elmar Veenendaal Karle Sykora Zewdu K.Tessema Addisu Asefa Plant ecology and Nature conservation Group Centre for Ecosystem StudiesWageningen UniversityDroevendaalsesteeg 3a6708PB WageningenThe Netherlands Rangeland ecology and Biodiversity Program College of Agriculture and Environmental SciencesHaramaya UniversityPO Box 138Dire DawaEthiopia Ethiopian Wildlife conservation Authority PO Box 386Addis AbabaEthiopia

The spatial pattern and abundance of herbaceous vegetation in semi-arid savannas are dictated by a complex and dynamic interaction between trees and grasses. Scattered trees alter the composition and spatial distribution of herbaceous vegetation under their canopies. Therefore, we studied the effect of Vachellia tortilis on herbaceous vegetation composition, biomass and basal area, and soil nutrients on sites with varying grazing intensities in the central rift valley of Ethiopia. Data were collected on species composition, cover and biomass of herbs and grasses, and soil moisture and nutrient contents under light,medium, and heavy grazing pressures, both under the inside and outside of V. tortilis canopies. Species richness was similar in both locations but decreased with increased grazing. Only the overall biomass and herb cover were significantly greater under the canopy than outside, and overall biomass showed significant unchanging decline with increased grazing. However, vegetation cover was significantly greater on moderately grazed sites compared to low and heavily grazed sites. All soil variables were significantly higher under V. tortilis canopies than *** findings suggest that V. tortilis has more effect on composition and diversity of herbaceous vegetation than on species richness, and that V. tortilis promotes the herbaceous layer biomass by reducing soil moisture loss and increasing soil fertility under the inside than outside the canopies. Therefore, we suggest that management practices should be directed on reducing pressure on V. tortilis by regulating grazing. Low to moderate grazing levels(i.e., a stocking rate less than 39.6 TLU ha-1yr-1) seems to be tolerable to ensure sustainable conservation of the species in the study area in particular and in semi-arid savannas in general.

关键词： Basal area cover Grazing pressure Inside/outside canopy Soil moisture

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conservation genetics of a resident population of Greylag Goose(Anser anser) at the southernmost limit of the species' distribution in Europe

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Avian Research 2019年第1期10卷 53-62页

作者： Anastasios Bounas Giorgos Catsadorakis Annita Logotheti Berend Voslamber Antonios Magoulas Dimitris Tsaparis Molecular ecology and conservation Genetics Lab Department of Biological Applications and TechnologyUniversity of Ioannina Society for the Protection of Prespa Sovon Dutch centre for Field Ornithology Institute of Marine Biology Biotechnology and Aquaculture(IMBBC)Hellenic Centre for Marine Research(HCMR)

Background:conservation of small and isolated populations can be challenging since they are prone to loss of genetic diversity due to random genetic drift and ***,information from the assessment of genetic diversity and structure are needed for conservation programs to determine the appropriate management strategy for the *** investigated the levels of genetic variability in a resident Greylag Goose(Anser anser) population,the southernmost breeding population of the species in Europe and the sole viable population of any goose species in ***:A fragment of mtDNA Control Region and a panel of 11 microsatellite markers were used to search for any signs of genetic impoverishment and population substructure and to reveal the underlying processes through the identification of possible past demographic ***:The population was found to be monomorphic in the amplified fragment of the mitochondrial Control Region,with all individuals sharing a single private *** showed a lack of any population substructure indicating a panmictic *** the population seems to have experienced a strong and recent genetic bottleneck and exhibits a small effective population size,we did not find evidence of either extremely low levels of genetic diversity or inbreeding ***:The recent demographic decline we detected and the combined influence of residency and anthropogenic factors have probably shaped the current genetic *** study population does not need emergency conservation actions but should be regarded as a discrete management *** management strategies should focus on population and genetic monitoring and preventing further abundance declines that would increase the risk of genetic impoverishment.

关键词： conservation Genetic variability Inbreeding Isolation Management units Microsatellites mtDNA Nonmigratory population

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