共查询到18条相似文献，搜索用时 46 毫秒
1.
2.
随着人们对资源的加速利用,生境丧失和破碎化导致物种濒危问题日益严重.以岛屿生物地理学为理论起源的种群生存力分析（PVA）,通过分析和模拟种群动态过程并建立灭绝概率与种群数量之间的关系,为濒危物种保护提供了重要的理论依据和研究途径.在过去的几十年中,种群生存力分析已成为保护生物学中一项重要的研究内容.目前种群生存力分析发展稳定,但对其实际预测能力和准确性尚存质疑,应用方面也有待进一步发展.种群生存力分析的进一步完善还需要在理论和方法上的创新,特别是籍于景观生态学和可持续性科学的理念,将空间分析手段、经济社会因素纳入到物种和种群的预测和管理上,从而使其具有更完整的理论基础和更高的实用价值.为此,本文对种群生存力分析的历史、基本概念、研究方法、模型应用和准确性进行了综述,并提出了有关的研究展望. 相似文献
3.
4.
秀丽高原鳅种群生存力分析及最小可存活种群数估算 总被引：1，自引：0，他引：1
秀丽高原鳅(Triplophysa venusta)系金沙江的土著种, 是云南省重要保护鱼类; 由于其栖息水域建设水电站, 加之云南连年干旱, 导致其种群数量锐减。采用漩涡模型对不同生境下的秀丽高原鳅种群生存力进行了模拟分析, 并估算了其最小可存活种群数。结果表明: 灾害是影响种群长期存活的关键因子, 种群繁殖率和性未成熟个体死亡率对种群生存力影响较大, 而种群的环境容纳量大小则无显著影响; 若连续进行40年的成鱼捕获(2000尾/年), 可使种群在100年内的灭绝概率增至100%, 而若连续进行20年的人工增殖放流(1000尾1龄鱼/年), 可使100年内的灭绝概率降至35.8%。通过模拟计算, 使种群在当前生境下以95%的概率存活100年所需的最小种群数为16000尾。由此可见, 减少灾害发生频率、降低性未成熟个体死亡率、增加繁殖率以及进行人工增殖放流是秀丽高原鳅种群保护与恢复的有效措施。研究为秀丽高原鳅种群保护、渔政管理与人工增殖放流提供了理论依据。 相似文献
5.
缪泸君;李言阔;叶晶;李佳;谢光勇;袁芳凯 《四川动物》2015,34(1):133-140
鄱阳湖区的獐种群是一个孤立的种群,近年来其数量急剧减少。本研究应用种群生存力分析的原理和方法,利用漩涡模型预测了鄱阳湖区獐种群在未来100 a内的种群变动趋势,并分析了不同场景下獐种群的变化趋势。结果表明:鄱阳湖区獐种群在未来100 a灭绝的概率是0.37。如果鄱阳湖区獐的栖息地进一步被破坏,獐种群的灭绝概率将大幅度增加;高概率的幼仔死亡率会使獐种群在未来100 a出现灭绝的概率为100%;灾害对种群的影响也很大,在洪灾和狩猎的双重作用下,洪灾发生频率增加将使獐种群灭绝概率增大。通过本次对鄱阳湖区獐的种群生存力分析,发现幼仔的死亡率和栖息地的破碎化是鄱阳湖区獐种群的重要制约因素,建议在獐栖息地之间设立生态走廊,加大对偷猎的打击力度,将有利于该地区獐种群的长期发展。 相似文献
6.
黄腹角雉(Tragopan caboti)为我国特有珍稀雉类。目前,其野生种群仅分布于湖南东南部、浙江南部和西南部、江西、福建、广东北部和广西东北部,估计数量约为4000只。湖南省雉类繁殖基地自1997年通过对执法检查中获得的黄腹角雉个体进行收容、救护以及驯养繁殖工作以来,该人工种群已经成功繁殖4年,至2004年年底种群数量为131只。本文利用8年的驯养繁殖过程中获得的种群生态学参数,借助漩涡模型(Vortex9.51)对该种群100年内的动态进行了模拟。结果显示,按照过去8年的生存情况,该种群在100年灭绝的概率为97%。成年雌性的高死亡率和频繁的灾害是影响种群长期存活的两个关键因素。如果成年雌性的死亡率降低到饲养后3年(2002—2004年)时的水平,种群的灭绝概率降低至5%,如果同时控制灾害的发生,其灭绝概率降至0。增加环境容纳量没有降低种群的灭绝概率和增加其增长速度,但增加环境容纳量对100年后的种群数量和基因杂合度有明显的影响。在降低成年雌性死亡率和杜绝灾害发生的情况下,可以考虑对种群进行收获(用作向野外放养),每次收获的数量应该控制在5只成年雄性和5只成年雌,开始收获时间为种群连续繁殖10年以后。降低成年雌性的死亡率、杜绝食物中毒和火灾等灾害的发生以及增加环境容纳量是该人工饲养种群长期存活和发展壮大的重要管理手段。 相似文献
7.
8.
9.
唐家河大熊猫是一个包括3个亚种群的异质种群,借助于游涡模型（vortex 8.21),对唐家河大熊猫未来100a内的种群动态动物了模拟,并分析了不同因子对该种群命运的影响,结果表明,在不考虑近亲繁殖,灾害等因素的情况下,该种群100a内在总体上保持稳定,并略有增长,但种群基因杂合率下降,累积绝灭率增加,尤以薄衣沟亚种群为最,提高环境容纳量,补充外来个体等措施能在不同程度上有利于该种群的长期存活,而近亲繁殖,灾害等因素则大大加速了种群的灭绝步伐,另外,成功的迁移扩散有利于异质种群的稳定与发展,否则对数量稀少的大熊猫种群有害无益,最后提出了针对性的保护与管理建议。 相似文献
10.
盐城獐种群生存力的初步分析 总被引：6，自引：0，他引：6
本文采用Ｖｏｒｔｅｘ６．０计算机程序对盐城獐（Ｈｙｄｒｏｐｔｅｓｉｎｅｒｍｉｓ）种群的生存力进行了分析。结果表明：若无狩猎和海潮侵袭的影响,在能容纳５００头獐的栖息地中,盐城獐可长期生存。如狩猎死亡率达５％和１０％,拥有１００～２００头獐的种群分别在３２～５０年和１５～２７年内灭绝率超过５％;拥有３００～５００头的现存种群分别在９０～９５年和２９～４２年内灭绝率超过５％。在有海潮侵袭的栖息地中,不管现存种群多大,在未来２５年左右的时间内种群灭绝率大于５％,在５０年内种群绝灭的可能性超过５０％。根据该地的实际情况,建议在无海潮侵袭的堤内选择至少能容纳２００头獐的栖息地和在相临的堤外选择能容纳５００头獐的栖息地建立保护区,才能保证盐城獐种群长期生存。 相似文献
11.
Population viability analysis (PVA) has frequently been used in conservation biology to predict extinction rates for threatened or endangered species. In this study, we used VORTEX to model Korean long-tailed goral (Naemorhedus caudatus) using previously collected ecological data. We focused on modelling population extinction, mean population size and heterozygosity. The minimum viable population size was found to be at least 50 gorals for 100 years, regardless of carrying capacity. However, populations with fewer than 50 gorals could not remain successful in the model. Inbreeding depression, catastrophes and supplementation also affected patterns of population extinction, mean population size and heterozygosity. Supplementation with new individuals had the strongest effect on extinction, mean population size and heterozygosity, followed by initial population size, inbreeding, catastrophes and carrying capacity. These results suggest that a supplementation by extra goral individuals from goral proliferation facilities would be the most helpful means for the restoration programme. More Korean goral-specific information regarding demographic and habitat parameters is needed for further PVA of the species. 相似文献
12.
自然保护区设计的主要原理和方法 总被引：13，自引：0，他引：13
本文回顾了自然保护区设计的主要原理和方法。建立自然保护区的目的是防止物种绝灭和生物多样性消失。岛屿生物地理学的“平衡理论”的设计原则未涉及到物种绝灭的中心问题———种群生存力,所以该理论对保护实践贡献较小。种群生存力分析和最小可存活种群的理论及模型用于物种绝灭问题的研究,同时关键种的生存力用于确定生态系统的生存力,因而该理论和模型成为自然保护区设计的理论基础。保护评估方法已应用于自然保护区的选择和检验中。走廊辩论取代了ＳＬＯＳＳ辩论,成为自然保护区设计争论的热点 相似文献
13.
Brian Folt Jeffrey M. Goessling Anna Tucker Craig Guyer Sharon Hermann Ericha Shelton-Nix Conor McGowan 《The Journal of wildlife management》2021,85(4):617-630
Population viability analyses are useful tools to predict abundance and extinction risk for imperiled species. In southeastern North America, the federally threatened gopher tortoise (Gopherus polyphemus) is a keystone species in the diverse and imperiled longleaf pine (Pinus palustris) ecosystem, and researchers have suggested that tortoise populations are declining and characterized by high extinction risk. We report results from a 30-year demographic study of gopher tortoises in southern Alabama (1991–2020), where 3 populations have been stable and 3 others have declined. To better understand the demographic vital rates associated with stable and declining tortoise populations, we used a multi-state hierarchical mark-recapture model to estimate sex- and stage-specific patterns of demographic vital rates at each population. We then built a predictive population model to project population dynamics and evaluate extinction risk in a population viability context. Population structure did not change significantly in stable populations, but juveniles became less abundant in declining populations over 30 years. Apparent survival varied by age, sex, and site; adults had higher survival than juveniles, but female survival was substantially lower in declining populations than in stable ones. Using simulations, we predicted that stable populations with high female survival would persist over the next 100 years but sites with lower female survival would decline, become male-biased, and be at high risk of extirpation. Stable populations were most sensitive to changes in apparent survival of adult females. Because local populations varied greatly in vital rates, our analysis improves upon previous demographic models for northern populations of gopher tortoises by accounting for population-level variation in demographic patterns and, counter to previous model predictions, suggests that small tortoise populations can persist when habitat is managed effectively. © 2021 The Wildlife Society. 相似文献
14.
Line Holm Andersen Peter Sunde Irene Pellegrino Volker Loeschcke Cino Pertoldi 《Ecology and evolution》2017,7(24):10987-11001
The agricultural scene has changed over the past decades, resulting in a declining population trend in many species. It is therefore important to determine the factors that the individual species depend on in order to understand their decline. The landscape changes have also resulted in habitat fragmentation, turning once continuous populations into metapopulations. It is thus increasingly important to estimate both the number of individuals it takes to create a genetically viable population and the population trend. Here, population viability analysis and habitat suitability modeling were used to estimate population viability and future prospects across Europe of the Little Owl Athene noctua, a widespread species associated with agricultural landscapes. The results show a high risk of population declines over the coming 100 years, especially toward the north of Europe, whereas populations toward the southeastern part of Europe have a greater probability of persistence. In order to be considered genetically viable, individual populations must count 1,000–30,000 individuals. As Little Owl populations of several countries count <30,000, and many isolated populations in northern Europe count <1,000 individuals, management actions resulting in exchange of individuals between populations or even countries are probably necessary to prevent losing <1% genetic diversity over a 100‐year period. At a continental scale, a habitat suitability analysis suggested Little Owl to be affected positively by increasing temperatures and urban areas, whereas an increased tree cover, an increasing annual rainfall, grassland, and sparsely vegetated areas affect the presence of the owl negatively. However, the low predictive power of the habitat suitability model suggests that habitat suitability might be better explained at a smaller scale. 相似文献
15.
Forecasting population decline to a certain critical threshold (the quasi-extinction risk) is one of the central objectives of population viability analysis (PVA), and such predictions figure prominently in the decisions of major conservation organizations. In this paper, we argue that accurate forecasting of a population's quasi-extinction risk does not necessarily require knowledge of the underlying biological mechanisms. Because of the stochastic and multiplicative nature of population growth, the ensemble behaviour of population trajectories converges to common statistical forms across a wide variety of stochastic population processes. This paper provides a theoretical basis for this argument. We show that the quasi-extinction surfaces of a variety of complex stochastic population processes (including age-structured, density-dependent and spatially structured populations) can be modelled by a simple stochastic approximation: the stochastic exponential growth process overlaid with Gaussian errors. Using simulated and real data, we show that this model can be estimated with 20-30 years of data and can provide relatively unbiased quasi-extinction risk with confidence intervals considerably smaller than (0,1). This was found to be true even for simulated data derived from some of the noisiest population processes (density-dependent feedback, species interactions and strong age-structure cycling). A key advantage of statistical models is that their parameters and the uncertainty of those parameters can be estimated from time series data using standard statistical methods. In contrast for most species of conservation concern, biologically realistic models must often be specified rather than estimated because of the limited data available for all the various parameters. Biologically realistic models will always have a prominent place in PVA for evaluating specific management options which affect a single segment of a population, a single demographic rate, or different geographic areas. However, for forecasting quasi-extinction risk, statistical models that are based on the convergent statistical properties of population processes offer many advantages over biologically realistic models. 相似文献
16.
Theoretical and empirical work has shown that once reduced in size and geographical range, species face a considerably elevated risk of extinction. We predict minimum viable population sizes (MVP) for 1198 species based on long-term time-series data and model-averaged population dynamics simulations. The median MVP estimate was 1377 individuals (90% probability of persistence over 100 years) but the overall distribution was wide and strongly positively skewed. Factors commonly cited as correlating with extinction risk failed to predict MVP but were able to predict successfully the probability of World Conservation Union Listing. MVPs were most strongly related to local environmental variation rather than a species' intrinsic ecological and life history attributes. Further, the large variation in MVP across species is unrelated to (or at least dwarfed by) the anthropogenic threats that drive the global biodiversity crisis by causing once-abundant species to decline. 相似文献
17.
岛屿生物地理学理论：模型与应用 总被引：17，自引：1，他引：17
前言岛屿有许多显著特征,如地理隔离,生物类群简单。这些特点为重复性研究和统计学分析奠定了基础,从而有利于许多深入而细致的生物学研究。因此,岛屿为发展和检验自然选择、物种形成及演化,以及生物地理学和生态学诸领域的理论和假设,提供了重要的自然实验室。岛屿生物地理学理论(MacArthurwilson学说)即为岛屿生物学研究中所产生的著名理论之一。该理论发展之 相似文献
18.
A. F. De Bont 《Ostrich》2013,84(3):195-199
The global Blue Swallow Hirundo atrocaerulea was classified as Vulnerable in 2010 on account of its small and rapidly declining population estimated at less than 1 500 pairs. We undertook this study to gain a better understanding of the current status and threats facing this migratory species. Three previously unknown areas that might be part of the species' non-breeding range were identified in Kenya and northern Tanzania. Within its breeding range we identified three previously unknown areas of potentially suitable habitat, one in Tanzania and two in Malawi, which require further exploration. Population viability assessment predicted that the Blue Swallow population will decline by 8% in 10 years. The overall probability of extinction of the species in the wild is 3%. Minimum viable population size analysis suggests that a goal for the long-term conservation of the Blue Swallow should be to mitigate current threats that are driving declines such that the population increases to a minimum of 3 600 individuals. This should consist of at least 900 individuals in each of the four clusters identified, along with a minimum of 500 individuals in at least one of the meta-populations per cluster. The four clusters are located in (1) the southeasten Democratic Republic of the Congo, (2) highlands of southern Tanzania and northern Malawi, (3) eastern highlands of Zimbabwe and (4) South Africa and Swaziland. The current proportions of the Blue Swallow population in strictly protected and unprotected areas on their breeding grounds are 53% and 47%, respectively, whereas on their non-breeding grounds the corresponding percentages are 25% and 75%, respectively. Our reassessment of the Blue Swallow's risk of extinction indicates that it continues to qualify as Vulnerable according to the IUCN/SSC criteria C2a(i). 相似文献