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101.
Conservation genetics is a well‐established scientific field. However, limited information transfer between science and practice continues to hamper successful implementation of scientific knowledge in conservation practice and management. To mitigate this challenge, we have established a conservation genetics community, which entails an international exchange‐and‐skills platform related to genetic methods and approaches in conservation management. First, it allows for scientific exchange between researchers during annual conferences. Second, personal contact between conservation professionals and scientists is fostered by organising workshops and by popularising knowledge on conservation genetics methods and approaches in professional journals in national languages. Third, basic information on conservation genetics has been made accessible by publishing an easy‐to‐read handbook on conservation genetics for practitioners. Fourth, joint projects enabled practitioners and scientists to work closely together from the start of a project in order to establish a tight link between applied questions and scientific background. Fifth, standardised workflows simplifying the implementation of genetic tools in conservation management have been developed. By establishing common language and trust between scientists and practitioners, all these measures help conservation genetics to play a more prominent role in future conservation planning and management.  相似文献   
102.
Nest box supplementation is widely used to increase nest‐site availability for cavity nesting animals but the analysis of its effects on individuals breeding in natural cavities is often neglected. This study offers a novel restoration technique to revert abandonment of natural breeding sites by a secondary cavity avian bird, the European roller (Coracias garrulus), and other ecologically similar species. We found that, after a program of nest box supplementation with ensuing monitoring, rollers gradually abandon nesting in natural and seminatural cavities in favor of nest boxes because the latter are of higher quality. We examine whether reducing the entrance size of natural and seminatural cavities improves their suitability for rollers. A 6‐year program reduced the diameter of the entrance of sandstone cavities and cavities in bridges. This led to a high occupancy (59%) of manipulated nest‐sites. Manipulated sites were most frequently occupied by rollers and little owls (Athene noctua) (31 and 18% of sites, respectively). Manipulation did not affect clutch size or fledgling success. We suggest that nest‐site diversity and nesting in natural cavities should be preserved to reduce nest box dependence. Our study illustrates the value of nest boxes when used alongside restoration of natural breeding sites and provides insights for the management of natural cavities.  相似文献   
103.
Climate change threatens organisms in a variety of interactive ways that requires simultaneous adaptation of multiple traits. Predicting evolutionary responses requires an understanding of the potential for interactions among stressors and the genetic variance and covariance among fitness‐related traits that may reinforce or constrain an adaptive response. Here we investigate the capacity of Acropora millepora, a reef‐building coral, to adapt to multiple environmental stressors: rising sea surface temperature, ocean acidification, and increased prevalence of infectious diseases. We measured growth rates (weight gain), coral color (a proxy for Symbiodiniaceae density), and survival, in addition to nine physiological indicators of coral and algal health in 40 coral genets exposed to each of these three stressors singly and combined. Individual stressors resulted in predicted responses (e.g., corals developed lesions after bacterial challenge and bleached under thermal stress). However, corals did not suffer substantially more when all three stressors were combined. Nor were trade‐offs observed between tolerances to different stressors; instead, individuals performing well under one stressor also tended to perform well under every other stressor. An analysis of genetic correlations between traits revealed positive covariances, suggesting that selection to multiple stressors will reinforce rather than constrain the simultaneous evolution of traits related to holobiont health (e.g., weight gain and algal density). These findings support the potential for rapid coral adaptation under climate change and emphasize the importance of accounting for corals’ adaptive capacity when predicting the future of coral reefs.  相似文献   
104.
城市建设中的矿物质材料开发利用活动不仅导致大量碳排放,也产生了碳吸收.以往建筑矿物质材料的碳吸收过程一直没有得到重视和科学量化.本研究采用遥感影像阴影高度反演技术,提取地块的建筑容量,识别建筑类型,以此为依据确定矿物材料用量及碳含量参数,采用热重分析法测定碳化率,基于以上步骤构建城市建筑碳汇量的核算方法,并选取沈阳市蒲河新来测试这一核算方法,同时进行不确定性分析.结果表明: 1996—2016年,沈阳市蒲河新城各类型建筑产生的碳汇总量依次为:居住建筑>公共服务建筑>其他类建筑>商业金融建筑>工业建筑;各类建筑用地的碳汇容积率依次为:商业金融建筑>居住建筑>公共服务建筑>其他类建筑>工业建筑.本研究构建的基于建筑容量提取的城市尺度的建筑碳汇量核算方法,可以快速准确地估算不同类型城市建设用地无机材料产生的碳汇量.在城市自然碳汇有限条件下,利用建筑碳汇增加城市碳汇量,能够为我国城市低碳发展提供新的思路.  相似文献   
105.
Dispersal is thought to be an important process determining range size, especially for species in highly spatially structured habitats, such as tropical reef fishes. Despite intensive research efforts, there is conflicting evidence about the role of dispersal in determining range size. We hypothesize that traits related to dispersal drive range sizes, but that complete and comprehensive datasets are essential for detecting relationships between species’ dispersal ability and range size. We investigate the roles of six traits affecting several stages of dispersal (adult mobility, spawning mode, pelagic larval duration (PLD), body size, aggregation behavior, and circadian activity), in explaining range size variation of reef fishes in the Tropical Eastern Pacific (TEP). All traits, except for PLD (148 species), had data for all 497 species in the region. Using a series of statistical models, we investigated which traits were associated with large range sizes, when analyzing all TEP species or only species with PLD data. Furthermore, using null models, we analyzed whether the PLD‐subset is representative of the regional species pool. Several traits affecting dispersal ability were strongly associated with range size, although these relationships could not be detected when using the PLD‐subset. Pelagic spawners (allowing for passive egg dispersal) had on average 56% larger range sizes than nonpelagic spawners. Species with medium or high adult mobility had on average a 25% or 33% larger range, respectively, than species with low mobility. Null models showed that the PLD‐subset was nonrepresentative of the regional species pool, explaining why model outcomes using the PLD‐subset differed from the ones based on the complete dataset. Our results show that in the TEP, traits affecting dispersal ability are important in explaining range size variation. Using a regionally complete dataset was crucial for detecting the theoretically expected, but so far empirically unresolved, relationship between dispersal and range size.  相似文献   
106.
The selection of a nest site is crucial for successful reproduction of birds. Animals which re‐use or occupy nest sites constructed by other species often have limited choice. Little is known about the criteria of nest‐stealing species to choose suitable nesting sites and habitats. Here, we analyze breeding‐site selection of an obligatory “nest‐cleptoparasite”, the Amur Falcon Falco amurensis. We collected data on nest sites at Muraviovka Park in the Russian Far East, where the species breeds exclusively in nests of the Eurasian Magpie Pica pica. We sampled 117 Eurasian Magpie nests, 38 of which were occupied by Amur Falcons. Nest‐specific variables were assessed, and a recently developed habitat classification map was used to derive landscape metrics. We found that Amur Falcons chose a wide range of nesting sites, but significantly preferred nests with a domed roof. Breeding pairs of Eurasian Hobby Falco subbuteo and Eurasian Magpie were often found to breed near the nest in about the same distance as neighboring Amur Falcon pairs. Additionally, the occurrence of the species was positively associated with bare soil cover, forest cover, and shrub patches within their home range and negatively with the distance to wetlands. Areas of wetlands and fallow land might be used for foraging since Amur Falcons mostly depend on an insect diet. Additionally, we found that rarely burned habitats were preferred. Overall, the effect of landscape variables on the choice of actual nest sites appeared to be rather small. We used different classification methods to predict the probability of occurrence, of which the Random forest method showed the highest accuracy. The areas determined as suitable habitat showed a high concordance with the actual nest locations. We conclude that Amur Falcons prefer to occupy newly built (domed) nests to ensure high nest quality, as well as nests surrounded by available feeding habitats.  相似文献   
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109.
红火蚁Solenopsis invicta Buren工蚁活动能力与蚁群健康、环境条件等密切相关,对蚁群进行干扰会引起工蚁防卫和攻击行为。本文采用标尺插入法对蚁巢进行干扰破坏,测定了工蚁活动性指数,结果显示在相同干扰程度下活动性指数随蚁巢体积增大而增大,相同蚁巢时随着干扰程度增加而活动性指数先迅速增大后基本保持不变。间隔5 min对蚁巢实施连续干扰后工蚁活动性呈明显连续下降趋势,第5次干扰后工蚁的响应活动变得很弱,工蚁活动性指数与干扰时间之间关系符合二次曲线方程。  相似文献   
110.
红火蚁Solenopsis invicta Buren是国际最具危险性的入侵性物种之一,传播扩散速度快、适生能力强。云南由于其独特的地理和气候环境,给红火蚁的入侵和发生提供了丰富的栖息环境和食物。本研究对云南高海拔冷凉区域人工草坪条件下红火蚁婚飞有翅蚁、工蚁活动规律,以及蚁巢变化规律进行了系统的调查研究。结果表明,在人工草坪条件下,红火蚁婚飞活动主要发生在每年的5-8月,6月初和8月初为婚飞生殖蚁发生高峰期,婚飞生殖蚁数量分别达到390.33头/1 000 m^2和523.33头/1 000 m^2,分别占到全年婚飞生殖蚁总量的25.19%和33.77%;诱集工蚁数量在6月下旬-7月上旬、8月下旬-9月下旬达到两个高峰,合计诱集数量分别为634.66头/1 000 m^2和1 636.00头/1 000 m^2,分别占到全年诱集工蚁总量的44.59%和17.30%;新增蚁巢数量在6月1日-7月1日、8月16日、9月15日-12月16日、次年3月14日-4月15日为4个增长阶段,新增蚁巢数量分别为9.66个/1 000 m^2、4.33个/1 000 m^2、5.67个/1 000 m^2、2.00个/1 000 m^2、分别占到全年新增蚁巢总数的44.62%、20.00%、26.15%、9.23%。综合婚飞年度规律、全年诱集工蚁数量、活动蚁巢数量和新增蚁巢数量方面的结果,人工草坪条件下,6-9月为红火蚁的活动发生高峰期,结合当地的实际情况,建议每年的4-6月和8-9月采用毒饵与粉剂相结合的方式进行防治,在12月份采用低毒农药灌巢进行防治。  相似文献   
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