首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
基于生境等价分析法的胶州湾围填海造地生态损害评估   总被引:3,自引:0,他引:3  
李京梅  刘铁鹰 《生态学报》2012,32(22):7146-7155
围填海造地的生态损害是指围填海造地所引致的海洋生态系统服务功能的下降,包括生物资源消失、生态调节功能减弱以及生物栖息地破坏等。针对胶州湾围填海造地规模及其生态影响,使用生境等价分析法,对围填海造地的资源和生态服务功能的受损程度和补偿规模进行了评估。结果表明,1988-2005年胶州湾填海造地的资源生态受损程度为41.33%,以退田还海作为修复工程,修复期为8a,在5%的折现率水平下,修复工程的规模应为22.47 km2,才能使被填海域的生态服务功能恢复到初始水平。这一结论可作为地方政府对胶州湾围填海造地实施生态修复建设和生态补偿管理的技术依据。  相似文献   

2.
基于生境质量的唐县生态安全格局构建   总被引:3,自引:0,他引:3  
生态安全格局作为景观生态学的重点及热点,其识别与构建对维持区域生态安全及实现区域可持续发展具有重要作用.本研究以河北省唐县为研究区,基于2016年土地利用现状数据,利用InVEST模型评估生境质量,确定生态源地;然后选取土地利用类型、生境质量指数、植被覆盖度、距水域距离、距居民点距离、距道路距离等阻力因子构建阻力表面,并采用阻力阈值法进行生态安全分区;最后运用最小累积阻力模型(MCR)判定生态廊道,从而综合构建唐县生态安全格局.结果表明: 唐县生态源地占总面积的3.3%,主要分布在斑块面积较大的林地和水域中,河北省四大水库之一的西大洋水库也位于生态源地范围内;根据耗费阻力突变点,将研究区划分为禁止开发区、限制开发区、优化开发区和重点开发区,各区占地百分比分别为18.9%、43.6%、27.6%和9.9%;唐县潜在生态廊道总长度为333.52 km,优化后生态廊道总长度为263.91 km,有助于各种生态交流.研究结果对唐县土地资源的合理可持续利用具有重要指导意义,可为唐县土地规划布局决策提供理论和技术支撑.  相似文献   

3.
While it is generally assumed that specialist species are more vulnerable to disturbance compared with generalist counterparts, this has rarely been tested in coastal marine ecosystems, which are increasingly subject to a wide range of natural and anthropogenic disturbances. Habitat specialists are expected to be more vulnerable to habitat loss because habitat availability exerts a greater limitation on population size, but it is also possible that specialist species may escape effects of disturbance if they use habitats that are generally resilient to disturbance. This study quantified specificity in use of different coral species by six coral‐dwelling damselfishes (Chromis viridis, C. atripectoralis, Dascyllus aruanus, D. reticulatus, Pomacentrus moluccensis, and P. amboinensis) and related habitat specialization to proportional declines in their abundance following habitat degradation caused by outbreaks of the coral eating starfish, Acanthaster planci. The coral species preferred by most coral‐dwelling damselfishes (e.g., Pocillopora damicornis) were frequently consumed by coral eating crown‐of‐thorns starfish, such that highly specialized damselfishes were disproportionately affected by coral depletion, despite using a narrower range of different coral species. Vulnerability of damselfishes to this disturbance was strongly correlated with both their reliance on corals and their degree of habitat specialization. Ongoing disturbances to coral reef ecosystems are expected, therefore, to lead to fundamental shifts in the community structure of fish communities where generalists are favored over highly specialist species.  相似文献   

4.

Aims

Climate change is expected to have profound effects on species' distributions into the future. Freshwater fishes, an important component of freshwater ecosystems, are no exception. Here, we project shifts in suitable conditions for Australian freshwater fishes under different climate change scenarios to identify species that may experience significant declines in habitat suitability.

Location

Australia.

Methods

We use MAXENT bioclimatic models to estimate the effect of climate change on the suitable conditions for 154 species of Australian freshwater fishes, of which 109 are endemic and 29 are threatened with extinction. Suitable conditions for freshwater fish species are modelled using three different Earth System climate models (ESMs) under two different emission scenarios to the year 2100. For each species, we examine potential geographic shifts in the distribution of suitable conditions from the present day to 2100 and quantify how habitat suitability may change at currently occupied sites by the end of this century.

Results

Broadscale poleward shifts in suitable conditions are projected for Australian freshwater fishes by an average of up to 0.38° (~180 km) across all species, depending on the emission scenario. Considerable loss of suitable conditions is forecast to occur within currently recognized distributional extents by 2100, with a mean projected loss of up to 17.5% across species. Predicted geographic range shifts and declines are larger under a high-emission scenario. Threatened species are projected to be more adversely affected than nonthreatened species.

Main Conclusions

Our models identify species and geographic regions that may be vulnerable to climate change, enabling freshwater fish conservation into the future.  相似文献   

5.
An assessment of water and habitat quality, based on macroinvertebrate assemblage indices and qualitative habitat scores (QHS), was undertaken in the Honi and Naro Moru rivers, Kenya, in 2011. The two rivers are important as water sources for the local communities and as habitat for organisms such as invertebrates in the national parks there. The Naro Moru upstream site (QHS: 83%) is unmodified, with minimal human influence. The Honi downstream site and the Naro Moru midstream and downstream sites experienced moderate to large modifications in habitat and biota (QHS: 40–80%). South African scoring system (SASS) scores ranged from 43 (Naro Moru downstream) to 165 (Honi upstream), and there was a decrease in SASS scores with distance downstream. Based on the multimetric index (MI), the Honi and Naro Moru upstream and midstream sites have good water quality (MI: 0.6–0.8), whereas the Honi midstream and downstream sites, and the Naro Moru downstream site, have moderate water quality (MI: 0.4–0.6). Human activities had a negative effect on water quality and habitats. Preventive and conservation measures should be taken in the usage of the Naro Moru and Honi rivers.  相似文献   

6.
The lizard family Chameleonidae is one of the most distinctive taxa of all vertebrates. Nonetheless, despite great intrafamilial diversity, little research has been conducted on morphological variation among chameleons. As a first step in this direction, we took morphological measurements on the head, limbs, spines, and tail of 56 species. Our goals were to investigate whether morphological variation correlates with differences in ecology and to examine whether correlations exist among different aspects of morphology. Based on existing information, species were classified either as arboreal or terrestrial, the latter referring to species that are known to use the ground on a regular basis. This study confirms that considerable intrafamilial variation exists among chameleons and that these traits appear to be evolutionarily quite labile. Once the effects of size are removed, functionally related traits tend to covary; however, few correlations are observed between non-functionally related traits. Many differences in the lengths of the limbs and head elements were detected between terrestrial and arboreal species, but the functional and selective significance of these differences is not clear. Further research on chameleon behaviour and ecology is required to understand the factors contributing to chameleon morphological diversity. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 76 , 91–103.  相似文献   

7.
Habitat restoration is vital to ameliorate the effects of anthropogenic disturbances on animal habitats. We reviewed the peer‐reviewed literature to examine where and how habitat restoration is undertaken. Our aim was to identify key knowledge gaps as well as research and monitoring needs that can inform future restoration actions. We found: (1) marine and terrestrial actions focus most commonly on restoring vegetation, and freshwater actions focus on restoring the in‐channel habitat; (2) arthropods are the most common focal group; (3) there is often no collection of pre‐restoration data, so certainty in attributing environmental changes to restoration actions is limited; and (4) population and community measures are most commonly used in monitoring programs, which only show if animals are present at restored sites and not whether they are able to grow, survive, and reproduce. We highlight three important considerations for future restoration actions. First, more integration of knowledge among freshwater, marine, and terrestrial systems will help us to understand how, and why, restoration outcomes might vary in different contexts. Second, where possible, restoration projects should be assessed using before‐after‐control‐impact designs, which will provide the strongest evidence if desired restoration responses occur. Third, if the goal of restoration is to develop self‐sustaining breeding populations of target animals, then measures of fitness (i.e. breeding, survival) should be collected. These recommendations will hopefully help guide more effective restoration practices and monitoring in the future.  相似文献   

8.
A set of eight simple ecological and social principles is proposed that could enhance the understanding of what constitutes fish 'habitat' and, if implemented, could contribute to improved management and conservation strategies. The habitat principles are a small, interrelated sub‐set that may be coupled with additional ones to formulate comprehensive guidelines for management and conservation strategies. It is proposed that: 1) habitat can be created by keystone species and interactions among species; 2) the productivity of aquatic and riparian habitat is interlinked by reciprocal exchanges of material; 3) the riparian zone is fish habitat; 4) fishless headwater streams are inseparable from fish‐bearing rivers downstream; 5) habitats can be coupled – in rivers, lakes, estuaries and oceans, and in time; 6) habitats change over hours to centuries; 7) fish production is dynamic due to biocomplexity, in species and in habitats; 8) management and conservation strategies must evolve in response to present conditions, but especially to the anticipated future. It is contended that the long‐term resilience of native fish communities in catchments shared by humans depends on incorporating these principles into management and conservation strategies. Further, traditional strategies poorly reflect the dynamic nature of habitat, the true extent of habitat, or the intrinsic complexity in societal perspectives. Forward‐thinking fish management and conservation plans view habitat as more than water. They are multilayered, ranging from pools to catchments to ecoregions, and from hours to seasons to centuries. They embrace, as a fundamental premise, that habitat evolves through both natural and anthropogenic processes, and that patterns of change may be as important as other habitat attributes.  相似文献   

9.
Abstract 1. The ecological circumstances that precipitate speciation remain poorly understood. Here, a community of Heliconius butterflies in lowland Panama was studied to investigate patterns of pollen use, and more specifically the ecological changes associated with the recent divergence of Heliconius melpomene (Linnaeus) and H. cydno (Doubleday).
2. Considering the seven commonest Heliconius species in the community, 32 types of pollen or spore were encountered in pollen loads but only five pollen species were common. Systematic exploitation of pollen was therefore confined to a small proportion of the flowers visited.
3. Most of the variation in pollen load composition between individuals was explained by differences in collecting locality. The exception was Psiguria , which was used in all habitats by the melpomene / hecale clade far more than by the erato / sapho clade. This may suggest an ancestral switch within Heliconius towards increased reliance on Psiguria pollen.
4. Heliconius cydno and H. melpomene differed significantly in pollen load composition for three of the five most commonly collected pollen species. This is most probably explained by differences in habitat preference; H. melpomene and its co-mimic H. erato are found in open habitat while H. cydno and its co-mimic H. sapho are found in closed-canopy forest.
5. As melpomene and cydno are known to hybridise occasionally, such differences in adult microhabitat contribute to pre-mating isolation. Habitat divergence between H. cydno and H. melpomene , which is associated with changes in mimicry, must have played a role in their recent speciation.  相似文献   

10.
樊影  王宏卫  杨胜天  刘勤  衡嘉尧  高一薄 《生态学报》2021,41(19):7614-7626
随着生态文明建设上升为国家战略,生态安全与保护修复格局的识别成为国土空间规划战略中关于生态空间保护的重要内容。为了促进区域生态系统的保护修复及有效管理,从空间尺度上对区域生态安全和修复区域的识别必不可少。利用InVEST模型的Habitat Quality模块分析了阿勒泰地区1995年、2005年和2018年的生境质量变化状况,从生态环境保护的角度出发构建区域生态安全格局,结果发现:(1)1995-2018年阿勒泰地区生境质量处于中等水平,总体呈下降趋势,说明当地生态系统有不断退化趋势;(2)以生态结构系统性和生态过程完整性为目标,通过MSPA分析结合景观连通性识别出15块生态源地,处于阿勒泰北部的山间林地和乌伦古湖区域;利用ArcGIS软件的Cost Distance工具识别出阿勒泰地区有效生态廊道38条,长约2466km,总面积约80.08km2,其中草地和林地是生态廊道穿越的重点区域;识别出最小阻力路径与生态廊道交叉处的生态节点52个,主要分布在草地和林地区域;(3)通过生境质量与最小累积阻力值识别出三类生态保护关键区域,分别为生态涵养区、生态维护区和生态保育区,结合各类生态保护关键区域的存在的生态问题提出不同的生态保护方向。研究结果为阿勒泰地区生态保护修复按照三类生态保护分区分别提出了不同的保护方向,可为阿勒泰地区国土空间生态保护修复关键区域识别和为保障区域生态系统整体保护及可持续发展政策制定提供参考。  相似文献   

11.
生态补偿对大熊猫栖息地周边农户生态足迹的影响   总被引:2,自引:0,他引:2  
张玉波  王梦君  李俊清  何洧 《生态学报》2009,29(7):3569-3575
大熊猫栖息地正面临破碎化和人类活动干扰的威胁,如何减少这些威胁成为保护大熊猫这一生态旗舰物种的关键.通过实施生态补偿项目,充分考虑当地弱势群体生存和发展的权利,帮助其进行生计替代和能源替代,以减小生态系统所承受的压力.以120个项目农户作为研究对象,利用生态足迹方法,探讨了生态补偿项目对生活在关键生态区域内农村人口的影响.结果表明,在各种生态生产性土地中,农户对林地和草地生态占用最大,能源替代可以大幅降低农户的薪柴消耗水平,从而降低农户对林地的生态占用.通过调整农户的牲畜养殖模式,减小了放牧对草地资源的压力和对草地的生态占用.农户人均生态足迹由2005年的2.7346hm2减小至2007年的1.6325 hm2,对周边环境的压力降低,有利于保护和恢复珍稀野生动植物栖息地.  相似文献   

12.
Not only can teeth provide clues about diet, but they also can be indicators of habitat quality. Conspecific groups living in different habitats with different kinds of foods may exhibit different rates of dental attrition because their teeth are less well adapted to some foods than to others. Ecological disequilibrium describes the situation in which animals live in habitats to which they are relatively poorly adapted. We test whether dental senescence, the wear-related decrease in dental functionality that is associated with decreased survival of infants born to older Propithecus edwardsi females, can be explained by ecological disequilibrium. Specifically, we compare the rates of dental wear in sifaka groups living in nearby habitats that differ in the degree of anthropogenically induced disturbance. We hypothesize that sifakas living in disturbed areas have an unusual rate of tooth wear compared to those living in a more pristine area, and that dental senescence is a consequence of an atypically high wear rate in a degraded habitat. To test whether habitat quality affects tooth wear more generally, we compare rates of use-wear in two subsets of Microcebus rufus living in either relatively undisturbed or disturbed habitats. Contrary to our predictions, we did not detect different rates of tooth wear in disturbed versus undisturbed habitats for either species and consider that reproductively detrimental dental senescence in P. edwardsi females is unlikely to be a pathological consequence of ecological disequilibrium.  相似文献   

13.
14.
1. Fish and ducks often belong to the same local food web, and several studies indicate that there is a general negative effect of fish on breeding ducks. This pattern has so far been addressed mainly within the framework of competition for common invertebrate prey, while predation by large fish as a force behind settlement and abundance patterns in ducks remains largely unknown. This is the first study to address the effect of fish predation on breeding ducks, isolated from that of competition, and the first experiment to explore the ability of ducks to identify and avoid lakes with high risk of fish predation. 2. We used a before–after control–impact design and 11 naturally fishless lakes. Waterfowl on the lakes were surveyed during the breeding season of 2005. Large adult pike (Esox lucius) were added to two lakes in early spring 2008, and waterfowl surveys were repeated on all 11 lakes. 3. Pike introduction did not affect the number of pairs on lakes during the nesting season in any of three focal duck species (mallard Anas platyrhynchos, teal Anas crecca, and goldeneye Bucephala clangula). During the brood‐rearing season, however, there was a decrease in duck days in teal and goldeneye in lakes with pike, with similar trends observed in mallard. The number of goldeneye ducklings was also significantly lower in lakes with pike. We were unable to determine whether the response was attributable to direct pike predation or to broods leaving experimental lakes, but in either case, our study demonstrates high fitness costs for ducks breeding on lakes with pike. 4. The apparent inability of nesting ducks to detect pike and the clear fitness implications may influence the annual recruitment of ducks on a larger scale as pike are both common and widespread. Vegetation complexity and food abundance are likely to be of overriding importance when breeding ducks are choosing a nesting site. As pike have a strong influence on breeding birds, relying on vegetation and cues of food abundance, while ignoring indicators of predation risk from fish, could lead to lakes with pike acting as an ecological trap.  相似文献   

15.
Biodiversity is declining at a rapid pace and, with it, the ecosystem functions that support ecosystem services. To counter this, ecosystem restoration is necessary. While the relationship between biodiversity and ecosystem functioning has been studied in depth, the relationship between ecosystem restoration and ecosystem functioning is studied less. We performed an observational study in grasslands undergoing restoration management toward Nardus grassland. Eight ecosystem functions, representing flows of energy, matter or information between functional compartments, were measured across five successive restoration phases along the restoration gradient. The levels of functioning were then compared along the gradient for both the individual functions and a multifunctionality index. We hypothesized that plant richness increases when grasslands are more restored and this increase in biodiversity is paralleled by an increase in ecosystem functioning. In our study, the degraded grasslands, generally occurring on more nutrient-rich soils, were dominated by competitive fast-growing species, resulting in higher process rates and thus in higher, faster functioning. Likewise, more restored grasslands exhibited slower process rates and, thus, lower functioning. When studying ecosystem functioning, value judgments are easily made. Especially in a restoration context, high functioning does not necessarily equals well functioning, as this depends on the stakeholder perspective. We need to ask ourselves if a high functioning ecosystem is most desirable, especially in a restoration or conservation context. Policy frameworks will need to balance these goals.  相似文献   

16.
Whether speciation can advance to completion in the face of initially high levels of gene flow is a very controversial topic in evolutionary biology. Extensive gene exchange is generally considered to homogenize populations and counteract divergence. Moreover, the role of introgressive hybridization in evolution remains largely unexplored in animals, particularly in freshwater zooplankton in which allopatric speciation is considered to be the norm. Our work investigates the genetic structure of two young ecological species: the pond species, Daphnia pulex and the lake species, Daphnia pulicaria. Phylogenetic and population genetics analyses were conducted on mitochondrial NADH dehydrogenase 5 (ND5) gene, the nuclear Lactate dehydrogenase (Ldh) gene and 21 nuclear microsatellite markers in 416 individuals from habitats with various degrees of permanence. The strong and consistent phylogenetic discordance between nuclear and mitochondrial markers suggests a complex evolutionary history of multiple independent habitat transition events that involved hybridization and introgression between lake and pond Daphnia. On the other hand, the low level of contemporary gene flow between adjacent populations indicates the presence of effective habitat isolating barriers. The Daphnia system provides strong evidence for a divergence-with-gene flow speciation model that involves multiple habitat transition events.  相似文献   

17.
Sclerophrys perreti is a critically endangered Nigerian native frog currently imperilled by human activities. A better understanding of its potential distribution and habitat suitability will aid in conservation; however, such knowledge is limited for S. perreti. Herein, we used a species distribution model (SDM) approach with all known occurrence data (n = 22) from our field surveys and primary literature, and environmental variable predictors (19 bioclimatic variables, elevation and land cover) to elucidate habitat suitability and impact of climate change on this species. The SDM showed that temperature and precipitation were the predictors of habitat suitability for S. perreti with precipitation seasonality as the strongest predictor of habitat suitability. The following variable also had a significant effect on habitat suitability: temperature seasonality, temperature annual range, precipitation of driest month, mean temperature of wettest quarter and isothermality. The model predicted current suitable habitat for S. perreti covering an area of 1,115 km2. However, this habitat is predicted to experience 60% reduction by 2050 owing to changes in temperature and precipitation. SDM also showed that suitable habitat exists in south-eastern range of the inselberg with predicted low impact of climate change compared to other ranges. Therefore, this study recommends improved conservation measures through collaborations and stakeholder's meeting with local farmers for the management and protection of S. perreti.  相似文献   

18.
基于生境质量和生态响应的莱州湾生态环境质量评价   总被引:10,自引:0,他引:10  
莱州湾沿岸海域未来10a是山东省集约用海规划的重要区域。为了降低和减少用海工程对海洋生态系统可能产生的不利影响,确定集约用海适宜规模和科学选址,应用已构建的集约用海对海洋生态影响评价指标体系和方法,从生境质量和生态响应两方面对莱州湾2004年至2012年的生态环境质量状况进行了评价。结果表明:位于莱州湾西部和南部近岸海域的Ⅰ区和Ⅳ区生态环境质量达到"差"的等级,生境质量总体上处于轻度到中度污染水平,水质和生物质量污染较严重,生态受到中度到严重扰动,其中浮游植物和浮游动物密度偏离标准值较大,大型底栖生物密度和生物量总体偏离标准值不大,但其物种组成已发生了明显变化,鱼卵和仔鱼数量急剧下降。在这两个区域要严格控制集约用海工程规模和新的污染排放,密切关注其对海洋生态的影响。位于莱州湾中部和东部的Ⅱ区和Ⅲ区生态环境质量接近"一般"等级,生境质量总体上处于轻度污染水平,水质受到一定程度污染,生态处于中度扰动状况。总体上,2011年和2012年莱州湾生态环境质量综合指数E值明显高于其他年份,生态环境有明显好转趋势。  相似文献   

19.
基于生态系统的海洋管理采用生态边界而非行政边界来指导管理实践, 海洋生境制图旨在探寻海洋环境与生物群落/物种的分布规律, 从而为生物多样性保护和海洋空间规划等管理行动提供可以依循的生态边界。海洋生境制图是科研监测数据通往管理决策应用的有效途径, 近年来已成为海洋生态保护与管理领域的国际研究热点, 但我国对于海洋生境制图的研究才刚刚起步。本文对海洋生境制图的国内外研究进展进行了综述, 介绍了海洋生境制图的定义和内涵, 明确了海洋生境制图的步骤及其在生态系统管理中的应用; 系统阐述了海洋生境制图的主要研究方法, 从生境分类方案、生境分区和生态特征描述等方面对海洋生境制图的研究过程及采用的分析方法进行了总结; 全面梳理了国内外的代表性海洋生境制图研究案例, 对各国已开发的海洋生境分类分区体系进行了对比和评述, 总结了共性特征; 最后提出研究建议, 对我国开展海洋生境制图研究的前景进行展望, 以期为我国的海洋生态空间管理工作提供科学依据和参考。  相似文献   

20.
Habitat degradation through anthropogenic development is a key driver of biodiversity loss. One way to compensate losses is “biodiversity offsetting” (wherein biodiversity impacted is “replaced” through restoration elsewhere). A challenge in implementing offsets, which has received scant attention in the literature, is the accurate determination of residual biodiversity losses. We explore this challenge for offsetting gas extraction in the Ustyurt Plateau, Uzbekistan. Our goal was to determine the landscape extent of habitat impacts, particularly how the footprint of “linear” infrastructure (i.e. roads, pipelines), often disregarded in compensation calculations, compares with “hub” infrastructure (i.e. extraction facilities). We measured vegetation cover and plant species richness using the line‐intercept method, along transects running from infrastructure/control sites outward for 500 m, accounting for wind direction to identify dust deposition impacts. Findings from 24 transects were extrapolated to the broader plateau by mapping total landscape infrastructure network using GPS data and satellite imagery. Vegetation cover and species richness were significantly lower at development sites than controls. These differences disappeared within 25 m of the edge of the area physically occupied by infrastructure. The current habitat footprint of gas infrastructure is 220 ± 19 km2 across the Ustyurt (total ~ 100,000 km2), 37 ± 6% of which is linear infrastructure. Vegetation impacts diminish rapidly with increasing distance from infrastructure, and localized dust deposition does not conspicuously extend the disturbance footprint. Habitat losses from gas extraction infrastructure cover 0.2% of the study area, but this reflects directly eliminated vegetation only. Impacts upon fauna pose a more difficult determination, as these require accounting for behavioral and demographic responses to disturbance by elusive mammals, including threatened species. This study demonstrates that impacts of linear infrastructure in regions such as the Ustyurt should be accounted for not just with respect to development sites but also associated transportation and delivery routes.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号