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11.
HALLEY M. S. DURRANT CHRISTOPHER P. BURRIDGE BRENDAN P. KELAHER NEVILLE S. BARRETT GRAHAM J. EDGAR MELINDA A. COLEMAN 《Conservation biology》2014,28(2):438-445
The global extent of macroalgal forests is declining, greatly affecting marine biodiversity at broad scales through the effects macroalgae have on ecosystem processes, habitat provision, and food web support. Networks of marine protected areas comprise one potential tool that may safeguard gene flow among macroalgal populations in the face of increasing population fragmentation caused by pollution, habitat modification, climate change, algal harvesting, trophic cascades, and other anthropogenic stressors. Optimal design of protected area networks requires knowledge of effective dispersal distances for a range of macroalgae. We conducted a global meta‐analysis based on data in the published literature to determine the generality of relation between genetic differentiation and geographic distance among macroalgal populations. We also examined whether spatial genetic variation differed significantly with respect to higher taxon, life history, and habitat characteristics. We found clear evidence of population isolation by distance across a multitude of macroalgal species. Genetic and geographic distance were positively correlated across 49 studies; a modal distance of 50–100 km maintained FST < 0.2. This relation was consistent for all algal divisions, life cycles, habitats, and molecular marker classes investigated. Incorporating knowledge of the spatial scales of gene flow into the design of marine protected area networks will help moderate anthropogenic increases in population isolation and inbreeding and contribute to the resilience of macroalgal forests. Implicaciones del Aislamiento por Distancia de Macroalgas para Redes de Áreas Marinas Protegidas 相似文献
12.
《Journal of Environmental Economics and Management》2014,67(3):510-522
We develop a biologically correct cost system for production systems facing invasive pests that allows the estimation of population dynamics without a priori knowledge of their true values. We apply that model to a data set for olive producers in Crete and derive from it predictions about the underlying population dynamics. Those dynamics are compared to information on population dynamics obtained from pest sampling with extremely favorable results. 相似文献
13.
RACHEL T. BUXTON CHRISTOPHER JONES HENRIK MOLLER DAVID R. TOWNS 《Conservation biology》2014,28(2):333-344
Eradication of introduced mammalian predators from islands has become increasingly common, with over 800 successful projects around the world. Historically, introduced predators extirpated or reduced the size of many seabird populations, changing the dynamics of entire island ecosystems. Although the primary outcome of many eradication projects is the restoration of affected seabird populations, natural population responses are rarely documented and mechanisms are poorly understood. We used a generic model of seabird colony growth to identify key predictor variables relevant to recovery or recolonization. We used generalized linear mixed models to test the importance of these variables in driving seabird population responses after predator eradication on islands around New Zealand. The most influential variable affecting recolonization of seabirds around New Zealand was the distance to a source population, with few cases of recolonization without a source population ≤25 km away. Colony growth was most affected by metapopulation status; there was little colony growth in species with a declining status. These characteristics may facilitate the prioritization of newly predator‐free islands for active management. Although we found some evidence documenting natural recovery, generally this topic was understudied. Our results suggest that in order to guide management strategies, more effort should be allocated to monitoring wildlife response after eradication. Conductores de la Recuperación de Poblaciones de Aves Marinas en Islas de Nueva Zelanda después de la Erradicación de Depredadores 相似文献
14.
针对辽宁省菱镁矿区资源状况与环境问题,提出菱镁矿区土地生态修复技术对策,包括土壤污染等级分类对策、不同立地条件土地复垦适宜性评价与对策、板结土壤复垦技术与对策和排土场贫瘠土壤肥力改良修复对策,进行适宜性复垦植物筛选与复垦效果评价。 相似文献
15.
Universal two-child policy has been implemented since the end of 2015 in China. This policy is anticipated to bring a significant increase in the total population, with profound influences on the resources and environment in the future. This paper analyzes the changing dynamics of urban and rural population, and forecasts urban and rural population from 2016 to 2030 at national and provincial scale using a double log linear regression model. Drawing upon the results of these two predictions, the impact of the population policy change on Chinese resources consumption and environmental pollution are predicted quantitatively. Given the future total population maintains current levels on resources consumption and environmental emission, the additional demand of resources and environment demand for the new population is forecasted and compared against the capacity on supply side. The findings are as follows: after implementing the universal two-child policy, China’s grain, energy consumption, domestic water demand, and pollutant emissions are projected to increase at different rates across provinces. To meet the needs arising from future population growth, food and energy self-sufficiency rate will be significantly reduced in the future, while relying more on imports. Stability of the water supply needs to be improved, especially in Beijing, Henan, Jiangsu, Qinghai, and Sichuan where the gap in future domestic water demand is comparatively larger. Environmental protection and associated governing capability are in urgent need of upgrade not least due to the increasing pressure of pollution. 相似文献
16.
李宏规 《中国人口.资源与环境》1992,(1)
人口是人口、资源与环境巨系统中最根本的因素。人口增长过快,将直接加大对资源与环境的压力,并影响人口素质的提高。所以,长期坚持实行计划生育这一基本国策是实现人口、资源、环境协调发展的重要保证。为此,必须要统一认识,增强控制人口的危机感和责任感;实施人口和计划生育目标管理责任制;扎实稳妥地做好农村计划生育工作;齐抓共管,保证人口计划的完成。 相似文献
17.
孙颔 《中国人口.资源与环境》1992,(1)
人口增多,耕地减少,部分地区供水不足,是我国人口与资源矛盾的基本格局。由于人口的压力,对资源实行超强度的利用,使较大范围的地区生态环境恶化,严重威胁农业生产,并成为许多地区多灾、低产、贫困的根本原因,较低的食物人均占有水平,将继续成为中国国民经济发展和人民生活水平提高的严重限制因素。增加食物,必须挖掘资源的潜力,开源与节流相结合,以内涵挖潜为主。首先是要立足现有的耕地,致力于提高单产;同时,合理开发水域、山地、草地等资源,广辟食物来源,提高非耕地资源的生产力,提高林牧渔业的发展水平。耕地应以深度开发为主,走资源节约型(节地、节水、节时、节能)的集约化道路。 相似文献
18.
韩新民 《中国人口.资源与环境》1992,(4)
建国40多年来,淄博市的国民经济和社会事业迅速发展,已经成为一个以重工业为主体的重要工业城市。同时,随着经济规模的迅速扩大,人口、资源与环境三大问题越来越突出。面对这样的市情,淄博市采取各种措施,突出重点,集中力量主攻薄弱环节,严格控制人口增长,保护资源,综合整治污染,取得了很大成效,初步走上了经济和社会事业与人口、资源、环境协调发展的轨道。 相似文献
19.
陶战 《中国人口.资源与环境》1994,4(1):62-64
中国农业经历了多种策略阶段,可持续发展策略是新近出现的最先进、最适合现在和将来农业发展的策略。新策略带有系统性原理,其实质是发展与生态环境保护协调的农业。因此,可持续发展措施应同时重视解决农业经济发展与生态环境保护两方面的问题。据此,本文提出了六项措施。 相似文献
20.
李远 《中国人口.资源与环境》1994,4(1):80-84
本文通过对乡镇工业经济发展现状及其环境问题的评价分析,提出乡镇工业环境管理应按本地自然条件、经济发展水平和乡镇企业的特点,实施分区域、按行业、有重点地进行管理的防治战略。并建议我国环境管理在以城市和大工业为重点的同时,及早将乡镇工业污染防治工作放在战略高度加以重视,切实加强乡镇工业环境管理。 相似文献