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171.
Caroline Moussy Ian J. Burfield P. J. Stephenson Arabella F. E. Newton Stuart H. M. Butchart William J. Sutherland Richard D. Gregory Louise McRae Philip Bubb Ignacio Roesler Cynthia Ursino Yanqing Wu Ernst F. Retief Jihad S. Udin Ruslan Urazaliyev Lina M. Sánchez-Clavijo Eric Lartey Paul F. Donald 《Conservation biology》2022,36(1):e13721
Species monitoring, defined here as the repeated, systematic collection of data to detect long-term changes in the populations of wild species, is a vital component of conservation practice and policy. We created a database of nearly 1200 schemes, ranging in start date from 1800 to 2018, to review spatial, temporal, taxonomic, and methodological patterns in global species monitoring. We identified monitoring schemes through standardized web searches, an online survey of stakeholders, in-depth national searches in a sample of countries, and a review of global biodiversity databases. We estimated the total global number of monitoring schemes operating at 3300–15,000. Since 2000, there has been a sharp increase in the number of new schemes being initiated in lower- and middle-income countries and in megadiverse countries, but a decrease in high-income countries. The total number of monitoring schemes in a country and its per capita gross domestic product were strongly, positively correlated. Schemes that were active in 2018 had been running for an average of 21 years in high-income countries, compared with 13 years in middle-income countries and 10 years in low-income countries. In high-income countries, over one-half of monitoring schemes received government funding, but this was less than one-quarter in low-income countries. Data collection was undertaken partly or wholly by volunteers in 37% of schemes, and such schemes covered significantly more sites and species than those undertaken by professionals alone. Birds were by far the most widely monitored taxonomic group, accounting for around half of all schemes, but this bias declined over time. Monitoring in most taxonomic groups remains sparse and uncoordinated, and most of the data generated are elusive and unlikely to feed into wider biodiversity conservation processes. These shortcomings could be addressed by, for example, creating an open global meta-database of biodiversity monitoring schemes and enhancing capacity for species monitoring in countries with high biodiversity. Article impact statement: Species population monitoring for conservation purposes remains strongly biased toward a few vertebrate taxa in wealthier countries. 相似文献
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Ina Fickelscher Heike Starke Eberhard Schulze Günther Ernst Nadezda Kosyakova Hasmik Mkrtchyan Kay MacDermont Neil Sebire Thomas Liehr 《黑龙江环境通报》2007,27(8):783-785
A prenatally ascertained case with a de novo small supernumerary marker chromosome (sSMC) derived from chromosome 1 is reported. Due to a fetal heart defect the parents decided in favour of an induced abortion. Postmortem, a molecular cytogenetic study on eleven formalin fixed, paraffin-embedded tissues of the fetus was performed, to further characterize the levels of mosaicism of the sSMC(1). sSMC presence varied between 13 and 62% within different tissues of sSMC carriers. This finding is something common in sSMC carriers and could explain why up to the present no clinical correlations for sSMC mosaicism and clinical outcome in the corresponding carriers could be established. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
174.
Ernst Terhardt 《Die Naturwissenschaften》1989,76(11):496-504
This study is concerned with the role and significance of "hearing out" pure tones in many types of sound. While for decades the phenomenon had played only a secondary role in auditory psychophysics, it is becoming now recognized as a key to auditory information acquisition. It is suggested that the auditory spectral pitches (i.e., the subjective pitches of pure tones) are in several respects analogous to visual contours; that both in visual and auditory perception contours convey most important information on external objects; and that contourization requires a decision process in the peripheral part of the sensory system and such can be regarded as the first step of sensory information processing. Recent experimental results on part-tone synthesis of audio signals are outlined that strongly emphasize the significance of part-tone hearing. 相似文献
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