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1.
Extirpated organisms are reintroduced into their former ranges worldwide to combat species declines and biodiversity losses. The growing field of reintroduction biology provides guiding principles for reestablishing populations, though criticisms remain regarding limited integration of initial planning, modeling frameworks, interdisciplinary collaborations, and multispecies approaches. We used an interdisciplinary, multispecies, quantitative framework to plan reintroductions of three fish species into Abrams Creek, Great Smoky Mountains National Park, USA. We first assessed the appropriateness of habitat at reintroduction sites for banded sculpin (Cottus carolinae), greenside darter (Etheostoma blennioides), and mottled sculpin (Cottus bairdii) using species distribution modeling. Next, we evaluated the relative suitability of nine potential source stock sites using population genomics, abundance estimates, and multiple‐criteria decision analysis (MCDA) based on known correlates of reintroduction success. Species distribution modeling identified mottled sculpin as a poor candidate, but banded sculpin and greenside darter as suitable candidates for reintroduction based on species‐habitat relationships and habitats available in Abrams Creek. Genotyping by sequencing revealed acceptable levels of genetic diversity at all candidate source stock sites, identified population clusters, and allowed for estimating the number of fish that should be included in translocations. Finally, MCDA highlighted priorities among candidate source stock sites that were most likely to yield successful reintroductions based on differential weightings of habitat assessment, population genomics, and the number of fish available for translocation. Our integrative approach represents a unification of multiple recent advancements in the field of reintroduction biology and highlights the benefit of shifting away from simply choosing nearby populations for translocation to an information‐based science with strong a priori planning coupled with several suggested posteriori monitoring objectives. Our framework can be applied to optimize reintroduction successes for a multitude of organisms and advances in the science of reintroduction biology by simultaneously addressing a variety of past criticisms of the field.  相似文献   

2.

We recently reported that a genetic transformation of the RNA-Binding-Protein (McRBP), an RNA chaperone gene derived from common ice plant (Mesembryanthemum crystallinum), alleviated injury and loss of biomass production by salt stress in Eucalyptus camaldulensis in a semi-confined screen house trial. In this study, we assessed the potential environmental impact of the transgenic Eucalyptus in a manner complying with Japanese biosafety regulatory framework required for getting permission for experimental confined field trials. Two kinds of bioassays for the effects of allelopathic activity on the growth of other plants, i.e., the sandwich assay and the succeeding crop assay, were performed for three transgenic lines and three non-transgenic lines. No significant differences were observed between transgenic and non-transgenic plants. No significant difference in the numbers of cultivable microorganisms analyzed by the spread plate method were observed among the six transgenic and non-transgenic lines. These results suggested that there is no significant difference in the potential impact on biodiversity between the transgenic McRBP-E. camaldulensis lines and their non-transgenic comparators.

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3.
Purpose

The biosphere is progressively subjected to a variety of pressures resulting from anthropogenic activities. Habitat conversion, resulting from anthropogenic land use, is considered the dominant factor driving terrestrial biodiversity loss. Hence, adequate modelling of land use impacts on biodiversity in decision-support tools, like life cycle assessment (LCA), is a priority. State-of-the-art life cycle impact assessment (LCIA) characterisation models for land use impacts on biodiversity translate natural habitat transformation and occupation into biodiversity impacts. However, the currently available models predominantly focus on total habitat loss and ignore the spatial configuration of the landscape. That is, habitat fragmentation effects are ignored in current LCIAs with the exception of one recently developed method.

Methods

Here, we review how habitat fragmentation may affect biodiversity. In addition, we investigate how land use impacts on biodiversity are currently modelled in LCIA and how missing fragmentation impacts can influence the LCIA model results. Finally, we discuss fragmentation literature to evaluate possible methods to include habitat fragmentation into advanced characterisation models.

Results and discussion

We found support in available ecological literature for the notion that habitat fragmentation is a relevant factor when assessing biodiversity loss. Moreover, there are models that capture fragmentation effects on biodiversity that have the potential to be incorporated into current LCIA characterisation models.

Conclusions and recommendations

To enhance the credibility of LCA biodiversity assessments, we suggest that available fragmentation models are adapted, expanded and subsequently incorporated into advanced LCIA characterisation models and promote further efforts to capture the remaining fragmentation effects in LCIA characterisation models.

  相似文献   

4.
Culture collections of microorganisms can still hold undiscovered biodiversity; with molecular techniques, considerable progress has been made in characterizing microalgae which were isolated in the past and misidentified due to a lack of morphological features. However, many strains are still awaiting taxonomic reassessment. Here we analysed the phylogenetic position, morphology and ultrastructure of the strain CCALA 307 previously identified as Coccomyxa cf. gloeobotrydiformis Reysigl isolated in 1987 from field soil in South Bohemia, Czech Republic. Molecular phylogenetic analyses based on SSU rDNA and the plastid rbcL gene revealed that the strain CCALA 307 formed a distinct sister lineage to Neocystis and Prasiola clades within the Trebouxiophyceae. We describe this strain as a new genus and species, Lunachloris lukesovae. Multiple conserved nucleotide positions identified in the secondary structures of the highly variable ITS2 rDNA barcoding marker provide further evidence of the phylogenetic position of Lunachloris. Minute vegetative cells of this newly recognized species are spherical or ellipsoid, with a single parietal chloroplast without a pyrenoid. Asexually, it reproduces by the formation of 2–6 autospores. Since the majority of recent attention has been paid to algae from the tropics or extreme habitats, the biodiversity of terrestrial microalgae in temperate regions is still notably unexplored and even a ‘common’ habitat like agricultural soil can contain new, as yet unknown species. Moreover, this study emphasizes the importance of culture collections of microorganisms even in the era of culture-independent biodiversity research, because they may harbour novel and undescribed organisms as well as preserving strains for future studies.  相似文献   

5.
Biodiversity losses over the next century are predicted to result in alterations of ecosystem functions that are on par with other major drivers of global change. Given the seriousness of this issue, there is a need to effectively monitor global biodiversity. Because performing biodiversity censuses of all taxonomic groups is prohibitively costly, indicator groups have been studied to estimate the biodiversity of different taxonomic groups. Quantifying cross-taxon congruence is a method of evaluating the assumption that the diversity of one taxonomic group can be used to predict the diversity of another. To improve the predictive ability of cross-taxon congruence in aquatic ecosystems, we evaluated whether body size, measured as the ratio of average body length between organismal groups, is a significant predictor of their cross-taxon biodiversity congruence. To test this hypothesis, we searched the published literature and screened for studies that used species richness correlations as their metric of cross-taxon congruence. We extracted 96 correlation coefficients from 16 studies, which encompassed 784 inland water bodies. With these correlation coefficients, we conducted a categorical meta-analysis, grouping data based on the body size ratio of organisms. Our results showed that cross-taxon congruence is variable among sites and between different groups (r values ranging between −0.53 to 0.88). In addition, our quantitative meta-analysis demonstrated that organisms most similar in body size showed stronger species richness correlations than organisms which differed increasingly in size (radj 2 = 0.94, p = 0.02). We propose that future studies applying biodiversity indicators in aquatic ecosystems consider functional traits such as body size, so as to increase their success at predicting the biodiversity of taxonomic groups where cost-effective conservation tools are needed.  相似文献   

6.
ABSTRACT

Background: Invasive plants can negatively impact native communities, but the majority of the effects of these invasions have been demonstrated only for temperate ecosystems. Tropical ecosystems, including the Cerrado, a biodiversity hotspot, are known to be invaded by numerous non-native species, but studies of their impacts are largely lacking.

Aims: Our research aimed at quantifying how Pinus spp. presence and density affected Cerrado plant communities.

Methods: We sampled areas invaded and non-invaded by Pinus spp. to determine if pine invasion affected native tree richness, diversity, evenness, and density. We also evaluated if community composition differed between invaded and non-invaded sites.

Results: We found invaded plots had lower native tree densities than non-invaded plots and that Pinus spp. invasions changed native tree communities by reducing native species abundances.

Conclusion: Invasive pines had negative impacts on the native Cerrado tree community by reducing native plant density and changing species abundances. Reduced density and abundance at early invasion stages can result in reduction in biodiversity in the long term.  相似文献   

7.
Abstract

Biodiversity comprises various levels of biological organisation. Global patterns of biodiversity are well established based on species occurrence. However, functional and historical processes underlying biodiversity patterns have been only recently approached. The increasingly active field of phylogenetics has allowed the rise of phylofloristic studies to help in elucidating the historical, evolutionary causes of plant biodiversity in addition to most commonly approached ecological correlates. Here, we review recent phylogeny-based studies disentangling the role of eco-geographic and historical factors on the biodiversity patterns of the Baetic–Rifan range and exemplify the use of barcoding to explore the evolutionary assembly of woody flora in the Spanish Sierra Nevada mountain range super-hotspot. Our species-level DNA barcoding approach resulted in a phylogeny potentially improving refinement of hypotheses in comparison with previous approaches based on phylogenies at genus level, and providing insights into the woody flora of Sierra Nevada subjected to systematic discussion. We show that the roles of elevation and substrate in biodiversity distribution vary according to the biodiversity component considered and also between endemic and non-endemic flora. We aim to illustrate how modern methods can further our understanding of the mechanisms underlying the assemblage of species and, consequently, the conservation of biodiversity.  相似文献   

8.
【目的】筛选油藏内源功能微生物并探究其驱油机理,现场试验以确定油藏内源微生物提高原油采收技术应用的工艺和技术可行性。【方法】采集英东油田样品,利用原油平板筛选驱油功能菌,评价其环境适应性并优化培养条件,通过乳化性能、降黏防蜡和烃转化能力等评估其驱油性能并探索其潜在机制,并在油田现场进行微生物强化驱油试验。【结果】从油水样品中分离到的贝莱斯芽孢杆菌(Bacillus velezensis) B6,其乳化活性指数(emulsifying activity index, EI24)值为100.00%,降黏率为97.20%,防蜡率为86.90%,表明菌株B6具有良好的乳化降黏性能,具有提高原油采收的潜力,并且能够减少原油中的重质组分而增加轻质烃类,改善原油物性,提升原油品质。进一步在英东油田、跃进油田和花土沟油田进行微生物单井吞吐和清防蜡作业,共进行62井次现场试验,累计增油1 460.36 t,平均延长洗井周期47 d,经济效益为342.50万元,投入产出比为1:4。【结论】通过室内研究和现场试验,证实内源微生物Bacillus velezensisB6具有显著提高原油采收和油井清防蜡的效果,应用潜力巨大。  相似文献   

9.
生物多样性与生态系统服务评估指标与方法   总被引:4,自引:0,他引:4  
于丹丹  吕楠  傅伯杰 《生态学报》2017,37(2):349-357
评估、模拟和预测全球生物多样性和生态系统服务的状态、趋势及其对人类福祉的影响,是当前生物多样性和生态系统服务研究领域的重要任务。指标和数据、模型和情景是推动生物多样性与生态系统服务评估研究理论建设和方法集成的重要工具。但是,目前对生物多样性和生态系统服务评估的指标体系和技术方法的综合对比研究相对缺乏。因而,系统评述了生物多样性和生态系统服务评估的概念框架、评估指标以及各类评估模型和方法的最新进展。生物多样性—生态系统功能—生态系统服务—人类福祉的级联框架是极具逻辑性的生物多样性和生态系统服务评估框架。现有的评估指标体系和模型方法还存在很多的问题和挑战,难以充分揭示生态系统服务的形成和影响机制、服务之间的联系和作用机理,有效地指导生态系统服务管理和决策制定。然而,这些评估指标和方法可为构建生物多样性与生态系统服务综合集成模型研究的框架提供重要的切入点。基于此,提出了生物多样性与生态系统服务综合集成模型研究的核心内容:i)目的:基于自然—社会综合特征的情景分析确定所解决的科学问题,输出生态系统服务管理和决策制定方案;ii)内容:尺度、生态系统服务类型、生物多样性的层次结构、组分间相互关系、驱动要素、多源数据的综合分析;iii)方法:对现有的各类模型和模型组合进行比较和不确定性分析,建立符合区域实际需求的生物多样性与生态系统服务综合制图模型库。在此基础上,建议我国应尽快发展适合中国区域特点的标准化指标体系和综合评估模型系统,定期对生物多样性和生态系统服务进行综合评估,掌握生物多样性和生态系统服务的变化趋势,提升我国在生物多样性和生态系统服务研究领域的国际地位和话语权。  相似文献   

10.
Exploring the relationships between the biodiversity of groups of interacting organisms yields insight into ecosystem stability and function (Hooper et al. 2000 ; Wardle 2006 ). We demonstrated positive relationships between host plant richness and ectomycorrhizal (EM) fungal diversity both in a field study in subtropical China (Gutianshan) and in a meta‐analysis of temperate and tropical studies (Gao et al. 2013 ). However, based on re‐evaluation of our data sets, Tedersoo et al. ( 2014 ) argue that the observed positive correlation between EM fungal richness and EM plant richness at Gutianshan and also in our metastudies was based mainly from (i) a sampling design with inconsistent species pool and (ii) poor data compilation for the meta‐analysis. Accordingly, we checked our data sets and repeated the analysis performed by Tedersoo et al. ( 2014 ). In contrast to Tedersoo et al. ( 2014 ), our re‐analysis still confirms a positive effect of plant richness on EM fungal diversity in Gutianshan, temperate and tropical ecosystems, respectively.  相似文献   

11.
【目的】作为典型的荒漠动物,骆驼能够采食其他动物不能够食用的具有强烈气味的或有毒的植物,而不影响其正常生理代谢。研究发现骆驼采食的植物毒素与吡啶、喹啉、吲哚等杂环化合物具有相似的化学结构,所以研究骆驼体内是否存在潜在的杂环化合物降解菌具有重要意义。【方法】本研究采集3头骆驼瘤胃内容物,分别以吡啶、喹啉和吲哚3种含氮杂环化合物为唯一碳源和氮源进行5代富集培养。通过高通量测序技术对瘤胃内容物和5代富集培养细菌进行了测序分析。【结果】骆驼肠道中降解杂环化合物(吡啶、喹啉、吲哚)细菌群体样品中变形菌门、放线菌门、拟杆菌门、浮霉菌门和厚壁菌门等5个门类丰富度最高。骆驼瘤胃内降解吡啶的优势菌可能属于鞘氨醇杆菌属和不动杆菌属,降解吲哚的优势菌主要属于芽孢杆菌属,而降解喹啉的优势菌可能以赖氨酸芽孢杆菌属和鞘氨醇杆菌属为主。【结论】骆驼瘤胃原始样品经过吡啶、喹啉、吲哚富集5代后,与原始样品比较优势菌群发生了较大的改变,这说明骆驼瘤胃内蕴含降解吡啶、吲哚和喹啉的细菌,但对吡啶、吲哚和喹啉的降解过程中发挥降解作用的细菌群落存在差异。  相似文献   

12.
Abstract

Glycosylation is considered to be an important reaction for the chemical modification of compounds with useful biological activities. Glycoside hydrolases are biotechnologically attractive enzymes which can be used in synthetic reactions for assembling glycosidic linkages with absolute stereoselectivity at an anomeric centre. Most of these enzymes are commercially available but there is great interest in the search for new biocatalysts with original catalytic characteristics. The marine environment has shown to be a very interesting source for new glycosyl hydrolases for both hydrolytic and synthetic aspects. In particular, Aplysia fasciata a marine herbivorous mollusc has been shown to be a potent producer of a library of glycoside hydrolases applied to the synthesis of glycosidic bonds. The impressive assortment of glycosidases in marine organisms clearly indicates that the potential biodiversity of these enzymes is still largely unexplored and that potential applications of biocatalysts from the sea will increase in the near future.  相似文献   

13.
Management strategies for the conservation of biodiversity can be developed only with precise information on the spatial distribution of organisms on relevant, mostly regional, spatial scales. Current surrogates for approximating the distribution of biodiversity are habitats mapped within a number of national and international frameworks (e.g., Natura 2000), even though conventional habitat mapping is time consuming and requires well-trained personnel. Here we evaluated the use of light detection and ranging (LiDAR) to map forest habitat types to simplify the process. We used available data of habitat types for the Bavarian Forest National Park as a basis to predict habitat types with LiDAR-derived variables. Furthermore, we compared these results with predictions based on extensive ground-based climate, soil and vegetation data. Using linear and flexible discriminant analyses, we found that LiDAR is able to predict forest habitat types with the same overall accuracy as the extensive ground data for climate, soil and vegetation composition. Subtle differences in the vegetation structure between habitat types, particularly in the vertical and horizontal vegetation profiles, were captured by LiDAR. These differences in the physiognomy were in part caused by changes in altitude, which also influence tree species composition. We propose that the most-efficient way to identify forest habitat types according Natura 2000 is to combine remote-sensing LiDAR data with well-directed field surveys.  相似文献   

14.
Honkanen T  Jormalainen V 《Oecologia》2005,144(2):196-205
In this study, we examined genetic variation in resistance and tolerance to fouling organisms in the brown alga Fucus vesiculosus. We first grew 30 algal genotypes in the field, where we allowed fouling organisms to colonise the genotypes at natural levels. We then conducted a manipulative experiment, where we grew 20 genotypes of algae in aquaria with or without fouling organisms. We measured host resistance as the load of fouling organisms and tolerance as the slope of the regression of algal performance on fouling level. Fouling organisms decreased host growth and contents of phlorotannins and thus have the potential to act as selective agents on algal defenses. We found significant among-genotype variation in both resistance and tolerance to fouling. We did not find a trade-off between resistance and tolerance. We found a marginally significant cost of resistance, but no cost of tolerance. Our results thus indicate that both the tolerance and resistance of F. vesiculosus can evolve as a response to fouling and that the costs of resistance may maintain genetic variation in resistance.  相似文献   

15.
Summary

The ecological dangers of global climatic change are frequently discussed in relation to their threat to biodiversity. Oceanic Scotland, however, differs in many respects from else- where, both in the nature of the current climatic change and the biodiversity of the flora on which it reacts. Scottish habitats, such as those in the more peripheral regions, are rarely rich in species and biodiversity may not be a relevant concept for assessing the impact of environmental change. In species-poor habitats ecosystem health may be a more useful measure of potential survival capacity than species wealth. Examination of the homeo-static properties of plant communities, and their ability to withstand environmental change, could provide a more practical method of predicting which sections of the Scottish flora are at risk from climatic change as well as indicating possible remedial action. Case histories from coastal, wetland, forest and mountain sites are discussed in terms of their present ecological robustness and future potential for surviving expected changes in the Scottish environment.  相似文献   

16.
Entomopathogenic fungi are important natural enemies of insects. However, there is little information on the insect‐suppressive potential of these fungi and possible effects of farming management on this. Meanwhile, changes in natural landscapes due to agricultural intensification have caused considerable biodiversity loss and consequent decay of ecosystem services. However, the adoption of practices such as agroforestry in agroecosystems can foster abiotic and biotic conditions that conserve biodiversity, consequently restoring the provision of ecosystems services. Here, we assessed the effect of management systems (agroforestry or full‐sun) on the pest‐suppressive potential of entomopathogenic fungi in Brazilian coffee plantations. We used the insect bait method coupled with survival analyses to assess the speed of kill by entomopathogenic fungi and their presence in soil samples from both farming systems. We found that insects exposed to agroforestry soils died more quickly than insects exposed to full‐sun soils. Of the fungi isolated from the bait insects, Metarhizium was found most frequently, followed by Beauveria. Meanwhile, Fusarium was frequently isolated as primary or secondary infections. We propose that the differential survival of insects is indicative of a greater suppressive potential by entomopathogenic fungi in agroforestry, and that this could be promoted by the diversified landscape, microclimatic stability, and reduced soil disturbance in agroforestry systems. Furthermore, our results provide a useful demonstration of the potential use of the insect bait method to investigate pest‐suppressive potential through bait insect mortality, and we term this the “bait survival technique.”  相似文献   

17.
Open oceanic calcification is mainly driven by unicellular organisms and in particular by eukaryotes such as coccolithophores and foraminifers. Open ocean microcalcifiers, like most planktonic protists, are characterized by extremely fast generation times and occasional sexual reproduction. Populations can alternate between diploid and haploid stages, which often build different kinds of cell covers. In the most important pelagic calcifiers, the coccolithophores, the diploid and haploid stages, which can self‐replicate and grow independently, display radically different morphologies with different modes of calcification or even with the absence of calcification in at least one life cycle stage. Although life cycle strategies seem likely to fundamentally influence the where and when of open ocean calcification, this issue has yet to be seriously addressed in the natural environment. Here, we introduce a new morphogenetic method, “combined CaCO3 optical detection with fluorescent in situ hybridization,” or COD‐FISH, which is based on a combination of TSAFISH and polarized optical microscopy. This technique allows simultaneous assessment of the taxonomic and life cycle status of single coccolithophore cells collected from the ocean. We demonstrate the application of COD‐FISH using both laboratory culture and field samples and discuss its potential value for assessing the ecology, biodiversity, population structure, and life cycles of coccolithophores and other open ocean unicellular calcifiers.  相似文献   

18.
Background:

The wide availability of genome-scale data for several organisms has stimulated interest in computational approaches to gene function prediction. Diverse machine learning methods have been applied to unicellular organisms with some success, but few have been extensively tested on higher level, multicellular organisms. A recent mouse function prediction project (MouseFunc) brought together nine bioinformatics teams applying a diverse array of methodologies to mount the first large-scale effort to predict gene function in the laboratory mouse.

Results:

In this paper, we describe our contribution to this project, an ensemble framework based on the support vector machine that integrates diverse datasets in the context of the Gene Ontology hierarchy. We carry out a detailed analysis of the performance of our ensemble and provide insights into which methods work best under a variety of prediction scenarios. In addition, we applied our method to Saccharomyces cerevisiae and have experimentally confirmed functions for a novel mitochondrial protein.

Conclusion:

Our method consistently performs among the top methods in the MouseFunc evaluation. Furthermore, it exhibits good classification performance across a variety of cellular processes and functions in both a multicellular organism and a unicellular organism, indicating its ability to discover novel biology in diverse settings.

  相似文献   

19.
ABSTRACT

Subterranean rodents are interesting organisms for communication studies because of their fossorial way of life. Acoustic communication in the South American genus Ctenomys has not yet been studied even though this species is geographically widespread. This paper represents a preliminary survey of Ctenomys vocalizations. Three types of vocal signals were identified: S-, C- and G-signals. Using field, laboratory and literature data, we provide interpretations on the possible functions of these signals. S-signals are harsh and low-pitched putative spatial localization signals that may also encode for sexual identification. C-signals are relatively high-pitched and narrow-banded FM vocalizations that are sexual signals used by females in a copulatory context. Finally, G-signals are harsh and patternless sounds that are aggressive signals used in direct encounters with con- or hetero- specific individuals.  相似文献   

20.
《Plant Ecology & Diversity》2013,6(3-4):355-364
Background: The alpine treeline ecotone is regarded as a sensor of the effects of global change on alpine plant communities. However, little is known about how treeline dynamics influence the diversity and composition of alpine plant communities. Such information is necessary to forecast how ascending montane forests may affect the composition of alpine flora.

Aims: We analysed the temporal variations in tree cover, plant diversity and composition, and the effect of tree cover dynamics on field layer vegetation over a period of 11 years, at two alpine treeline ecotones in the central Pyrenees, Spain.

Methods: Tree and field layer vegetation was sampled in permanent transects in 1998 and 2009, using the point-intercept method. Temporal changes in tree cover, plant species richness and abundance were characterised along the ecotone by using a randomisation approach, rarefaction curves, and a non-parametric multivariate test, respectively.

Results: Tree cover increased significantly at one of the sites, whereas plant species richness only increased at the other site where tree cover had not changed. Vegetation composition changed significantly at both sites, but it was not spatially coupled with changes in tree cover along the ecotone.

Conclusions: A change of tree cover does not necessarily trigger changes in the ground flora at the treeline over relatively short periods (decade scale). The results challenge our ability to infer short-term biodiversity impacts from upslope advance of forests. Integrated tree and field layer monitoring approaches are necessary to produce a better understanding of the impact of ongoing global change on treeline ecotones.  相似文献   

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