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Andrea Mentges Shane A. Blowes Dorothee Hodapp Helmut Hillebrand Jonathan M. Chase 《Conservation biology》2021,35(2):688-698
Estimates of biodiversity change are essential for the management and conservation of ecosystems. Accurate estimates rely on selecting representative sites, but monitoring often focuses on sites of special interest. How such site-selection biases influence estimates of biodiversity change is largely unknown. Site-selection bias potentially occurs across four major sources of biodiversity data, decreasing in likelihood from citizen science, museums, national park monitoring, and academic research. We defined site-selection bias as a preference for sites that are either densely populated (i.e., abundance bias) or species rich (i.e., richness bias). We simulated biodiversity change in a virtual landscape and tracked the observed biodiversity at a sampled site. The site was selected either randomly or with a site-selection bias. We used a simple spatially resolved, individual-based model to predict the movement or dispersal of individuals in and out of the chosen sampling site. Site-selection bias exaggerated estimates of biodiversity loss in sites selected with a bias by on average 300–400% compared with randomly selected sites. Based on our simulations, site-selection bias resulted in positive trends being estimated as negative trends: richness increase was estimated as 0.1 in randomly selected sites, whereas sites selected with a bias showed a richness change of −0.1 to −0.2 on average. Thus, site-selection bias may falsely indicate decreases in biodiversity. We varied sampling design and characteristics of the species and found that site-selection biases were strongest in short time series, for small grains, organisms with low dispersal ability, large regional species pools, and strong spatial aggregation. Based on these findings, to minimize site-selection bias, we recommend use of systematic site-selection schemes; maximizing sampling area; calculating biodiversity measures cumulatively across plots; and use of biodiversity measures that are less sensitive to rare species, such as the effective number of species. Awareness of the potential impact of site-selection bias is needed for biodiversity monitoring, the design of new studies on biodiversity change, and the interpretation of existing data. 相似文献
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Dorothe Ehrich Niels M. Schmidt Gilles Gauthier Ray Alisauskas Anders Angerbjrn Karin Clark Frauke Ecke Nina E. Eide Erik Framstad Jay Frandsen Alastair Franke Olivier Gilg Marie-Andre Giroux Heikki Henttonen Birger Hrnfeldt Rolf A. Ims Gennadiy D. Kataev Sergey P. Kharitonov Siw T. Killengreen Charles J. Krebs Richard B. Lanctot Nicolas Lecomte Irina E. Menyushina Douglas W. Morris Guy Morrisson Lauri Oksanen Tarja Oksanen Johan Olofsson Ivan G. Pokrovsky Igor Yu. Popov Donald Reid James D. Roth Sarah T. Saalfeld Gustaf Samelius Benoit Sittler Sergey M. Sleptsov Paul A. Smith Aleksandr A. Sokolov Natalya A. Sokolova Mikhail Y. Soloviev Diana V. Solovyeva 《Ambio》2020,49(3):786-800
Lemmings are a key component of tundra food webs and changes in their dynamics can affect the whole ecosystem. We present a comprehensive overview of lemming monitoring and research activities, and assess recent trends in lemming abundance across the circumpolar Arctic. Since 2000, lemmings have been monitored at 49 sites of which 38 are still active. The sites were not evenly distributed with notably Russia and high Arctic Canada underrepresented. Abundance was monitored at all sites, but methods and levels of precision varied greatly. Other important attributes such as health, genetic diversity and potential drivers of population change, were often not monitored. There was no evidence that lemming populations were decreasing in general, although a negative trend was detected for low arctic populations sympatric with voles. To keep the pace of arctic change, we recommend maintaining long-term programmes while harmonizing methods, improving spatial coverage and integrating an ecosystem perspective. 相似文献
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Aim and Background
In 1999, under German Presidency, the European Council asked the European Commission to set up an approach with new instruments for a new European strategy on chemicals management. In 2001, the Commission subsequently published a White Paper called ‘Strategy for a future European chemicals policy’. After intensive discussions with all involved parties, a proposal for a new Regulation, called REACH, was brought in to Council and Parliament (co-decision procedure) in October 2003. Different impact assessments concerning the strategy of the White Paper presumed dramatically increasing costs for the chemical industry. Due to these discussions, the Government of North Rhine-Westphalia decided to conduct a pilot project on workability of the new requirements in the second half of 2003. The parties involved were administrations, producers, industrial associations, unions and NGOs. The focus was not to test the entire Regulation, but to analyse the practicability of selected processes, evaluations, and communication processes connected with the registration of substances.Results
Examining the requirements and processes with regard to their realization in practice, resulted in a list of well-founded proposals. These proposals concern modification in the Regulation itself, implementation tools required, and guidelines which will need to be available before the REACH system is launched. The pivot questions of the pilot testing were the acceptance of data of substance-effects and their evaluation in different application areas. The registration Agency (played by the German Competent Authorities) checked the presented documents concerning completeness and plausibility. For all presented papers inquiries were needed In summary, the simulation has provided concrete evidence of where and why REACH may cause problems. Lack of simple instruments and corresponding knowledge for conducting exposition scenarios were noticed. The simulation process facilitated a new communication of all parties along the supply chain. In addition, the development of new networks could be observed to ease co-operation between authorities and those active on the market. These networks continue to exist even after cessation of the pilot trial. 相似文献6.
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Taylor Jason J. Lawler James P. Aronsson Mora Barry Tom Bjorkman Anne D. Christensen Tom Coulson Stephen J. Cuyler Christine Ehrich Dorothee Falk Knud Franke Alastair Fuglei Eva Gillespie Mark A. Heiðmarsson Starri Høye Toke Jenkins Liza K. Ravolainen Virve Smith Paul A. Wasowicz Pawel Schmidt Niels Martin 《Ambio》2020,49(3):833-847
Ambio - This review provides a synopsis of the main findings of individual papers in the special issue Terrestrial Biodiversity in a Rapidly Changing Arctic. The special issue was developed to... 相似文献
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Ehrich Dorothée Schmidt Niels M. Gauthier Gilles Alisauskas Ray Angerbjörn Anders Clark Karin Ecke Frauke Eide Nina E. Framstad Erik Frandsen Jay Franke Alastair Gilg Olivier Giroux Marie-Andrée Henttonen Heikki Hörnfeldt Birger Ims Rolf A. Kataev Gennadiy D. Kharitonov Sergey P. Killengreen Siw T. Krebs Charles J. Lanctot Richard B. Lecomte Nicolas Menyushina Irina E. Morris Douglas W. Morrisson Guy Oksanen Lauri Oksanen Tarja Olofsson Johan Pokrovsky Ivan G. Popov Igor Yu. Reid Donald Roth James D. Saalfeld Sarah T. Samelius Gustaf Sittler Benoit Sleptsov Sergey M. Smith Paul A. Sokolov Aleksandr A. Sokolova Natalya A. Soloviev Mikhail Y. Solovyeva Diana V. 《Ambio》2020,49(3):801-804
Ambio - In the original published article, some of the symbols in figure 1A were modified incorrectly during the typesetting and publication process. The correct version of the figure is provided... 相似文献