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1.
珊瑚礁区的生物多样性及其生态功能   总被引:14,自引:0,他引:14  
珊瑚礁区生物多样性程度可以与陆地热带雨林相提并论,目前关于珊瑚礁物种多样性及其空间分布特征方面研究进展迅速,是生物多样性研究的重要基地。作为一种生态资源,珊瑚礁还具有重要的生态功能,近年来由于全球气候逐渐变暖、人类活动影响不断加剧,导致其生物多样性缩减、生态功能严重退化。珊瑚礁生态系统多样性、遗传多样性已成为珊瑚礁研究热点,珊瑚礁生态环境效应和保护管理方面的研究也越来越受到重视。我国珊瑚礁主要分布在广阔的南海海域和海南岛、台湾岛、香港和广东广西沿岸,礁区生物种类繁多,多样性程度较高,以往研究主要涉及地质、地貌、生物、环境等方面,现今和今后一段时间里迫切需要加强生物多样性和生态功能研究,以确保更有效地保护和管理珊瑚礁。  相似文献   

2.
生态遗传学在生物多样性保护中的作用   总被引:4,自引:0,他引:4  
本文就生态遗传学在生物多样性保护中的作用问题谈了几点看法。首先陈述了生态遗传学的性质,它是种群生态学和种群遗传学的结合,研究种群层次上正在进行着的进化;其次列举了生态遗传学的基本内容,说明生态遗传学是生物多样性研究和保护不可缺少的基本知识。最后举两个实例阐明生态遗传学在生物多样性保护中的具体应用。  相似文献   

3.
吴舒尧  黄姣  李双成 《生态学报》2017,37(20):6986-6999
全球范围内关键生态系统服务的减少使人类社会面临巨大的威胁,生物多样性是生态系统提供各种产品和服务的基础。生态恢复工程对退化的生态系统服务和生物多样性进行修复,对于缓解人类环境压力具有非常重要的意义。长期的理论和实践工作形成了多种生态恢复措施:(1)单纯基于生态系统自我设计的自然恢复方式,(2)人为设计对环境条件进行干预,反馈影响生态系统的自我设计,(3)人为设计对目标种群和生态系统进行直接干预和重建。这3类恢复方式可以在不同程度上定向的影响生态系统的恢复进程,反映了人类对生态系统的低度、中度和高度介入。哪种恢复方式和介入程度能够实现更好的恢复效果,是生态恢复学中的一个关键问题,但到目前为止,虽广有争议,却无定量的分析和结论。针对这个空白,通过对ISI Web of Knowledge数据库中生态恢复相关文献的整合分析,基于数学统计的方法定量比较在不同条件下低度介入(自然恢复)、中度介入(环境干预)和高度介入(直接干预)3种恢复方式对生态系统服务与生物多样性的恢复效果。论文从4个方面展开研究:(1)低度、中度、高度介入生态恢复方式的划分,(2)比较3大类介入方式对生态系统服务和生物多样性恢复效果的差异,(3)不同气候条件、生态系统类型和恢复时间等背景因素的影响,(4)生物多样性恢复和生态系统服务恢复之间的关系。研究结果揭示了不同生态恢复方式的适用条件,以及对生物多样性和生态系统恢复相互关系的作用,对生态恢复实践中恢复方式的选择有指导作用。对未来的研究也有启示意义,如针对特定生态系统服务或具体研究问题进一步探索低度、中度和高度介入生态恢复方式的作用规律和机制;将地区的社会经济水平、生态系统的受损程度等因素纳入生态恢复方式的考察,以最优化生态恢复成本-效率等。  相似文献   

4.
Conservation of biodiversity can generate considerable indirect economic value and this is being increasingly recognized in China. For a forest ecosystem type of a nature reserve, the most important of its values are its ecological functions which provide human beings and other living things with beneficial environmental services. These services include water conservancy, soil protection, CO2 fixation and O2 release, nutrient cycling, pollutant decomposition, and disease and pest control. Based on a case study in Changbaishan Mountain Biosphere Reserve in Northeast China, this paper provides a monetary valuation of these services by using opportunity cost and alternative cost methods. Using such an approach, this reserve is valued at 510.11 million yuan (USD 61.68 mill.) per year, 10 times higher than the opportunity cost (51.78 mill. yuan/ha.a) for regular timber production. While China has heeded United Nations Environmental Program (UNEP)'s call for economic evaluation of ecological functions, the assessment techniques used need to be improved in China and in the West for reasons mentioned.  相似文献   

5.
1. In this issue we aimed to answer the questions: (i) under what circumstances are functional variables better than structural ones for assessing ecosystem health? and (ii) are there good indicators of change in ecological functioning along perturbation gradients?
2. Of the numerous functional indicators tested in this issue, several show a response to anthropogenic stress and could be included in assessments of ecosystem health and integrity in running waters.
3. In three of eight studies, function showed a stronger response to anthropogenic stress than structure, whereas one study showed a response in structure and not function, and four studies showed responses in both structure and function. Thus structure alone could not detect all types of impairment and functional aspects should also be included and further developed for assessing running-water ecosystem health and integrity. Functional variables may be especially useful in situations where there is a stronger response among organisms not usually included in stream assessment (e.g. fungi and bacteria) than the commonly used invertebrate, macrophytes and fish indicators.
4. Leading research questions related to the use of functional indicators in running waters include: (i) how large is natural and operator-induced variation for functional indicators? (ii) how small of an effect size (delta) can be detected using structural versus functional indicators? and (iii) how do we efficiently improve theories as well as predictive ability for functional measures to assess the effects of anthropogenic stressors?
5. To advance the use of functional indicators in applied running-water studies, we need to supplement the approach of using large-scale datasets and correlation with ecosystem manipulations.  相似文献   

6.
7.
李爱民  邓合黎  马琦 《生态学报》2012,32(15):4869-4889
以重庆市生态功能区为基本单元,用1998—2010年间重庆市蝴蝶群落调查的成果,总结、分析与物种多样性相关的数据与参数,报道了重庆市生态功能区蝴蝶多样性参数。采用路线法的调查方法,设置调查样带14503条,获知重庆市分布蝶类492种,隶属于12科,187属,其中,优势种36个,占总数的7.3%,常见种182个(37.0%),少见种155个(31.5%),罕见种119个(24.2%)。依据生态服务功能重要性,划分为14个功能区。其中,1、10功能区物种数在250种以上,物种丰度在30以上,种类优势度低于0.10;2、5、9功能区150种以上,物种丰度20—30之间,种类优势度0.10—0.14间;8、11、12、13功能区低于60种,物种丰度低于10,种类优势度0.17—0.32间。但是,物种多样性指数是6、7两个功能区最高(>1.8),4、5、8、14功能区在1.70—1.76间,2、3、11、12功能区最低;均匀度则是4、8、11三个功能区高于0.4,6、7、14功能区在0.35—0.4间,1、2、12功能区最低。最高的相对多度出现在功能区13,是33.55×10-3,功能区12居第二位(11.54×10-3),第三位是功能区1(6.59×10-3);最低的相对多度出现在功能区12(0.67×10-3),倒数第二位是功能区7(1.02×10-3),倒数第三位是功能区11。按照监测种类和类群选择的原则,选出监测种类24个,其中,甲等监测种类8个,乙等8个,丙等8个;类群12个,其中I类6群,Ⅱ类6群。  相似文献   

8.
Current editorial policies of scientific journals in combination with modern technology used for the search of scientific literature intensify the tendency that ecologists lose connections with the knowledge of the past. This is unfortunate because the older ecological literature provides elements for a comparative approach linking ecological function, biodiversity and habitat of large-scale, high-biodiversity systems. Such a comparative approach, seeking common or diverging properties among larger systems, would be a useful complement to current small-scale experimentation, but would require testable hypotheses. Deriving observations, ideas and views from the older ecological literature, we propose such testable hypotheses, linking Ecological processes (EP), Biodiversity (BD), Habitat complexity (HC), Habitat harshness (HH), Habitat extent (HE), Size of organisms (S) and Longevity of organisms (L) in ecosystems throughEP α BDx1 α HCx2 α HH−x3 α HEx4 α Sx5 α Lx6.This set of allometric relations represents a sort of null model. We use heterotrophic stream ecosystems as an example to illustrate how these hypotheses could be tested, how observed deviations may improve the mechanistic understanding of a system and how our approach could serve to assess scenarios of biodiversity changes. We also briefly discuss how properties of different ecosystem types could be compared with our approach.Gegenwärtige Praktiken von Herausgebern wissenschaftlicher Zeitschriften sowie die Nutzung moderner Technologien bei der Beschaffung wissenschaftlicher Literatur verstärken die Tendenz, dass Ökologen älteres Wissen kaum noch beachten. Dies ist bedauerlich, da die ältere ökologische Literatur Elemente für eine vergleichende Methodik enthält, die ökologische Funktion, Biodiversität und Lebensraum von großräumigen, hochdiversen Systemen verknüpft. Solch eine vergleichende Methodik, die gemeinsame oder divergierende Eigenschaften von Systemen zu ergründen sucht, würde eine nützliche Ergänzung zu gegenwärtigen Experimenten mit kleineren Systemen sein. Allerdings benötigte man zur Anwendung dieser vergleichenden Methodik prüfbare Hypothesen. Wir schlagen solch prüfbare Hypothesen vor, die wir aus Beobachtungen, Ideen und Auffassungen der älteren ökologischen Literatur ableiten. Dafür verknüpfen wir ökologische Prozesse (EP), Biodiversität (BD), Lebensraumkomplexität (HC), Lebensraumrauheit (HH), Lebensraumausdehnung (HE), Körpergröße von Organismen (S) und Lebensdauer von Organismen (L) in Ökosystemen durchEP α BDx1 α HCx2 α HH−x3 α HEx4 α Sx5 α Lx6.Dieser Satz von allometrischen Beziehungen repräsentiert eine Art von Nullmodell. Am Beispiel heterotropher Fließwasserökosysteme zeigen wir, wie diese Hypothesen geprüft werden könnten, wie abweichende Beobachtungen das mechanistische Verständnis eines Systems verbessern könnten und wie unsere Methodik zur Beurteilung von Szenarien veränderter Biodiversität dienen könnte. Zudem diskutieren wir, wie Eigenschaften verschiedener Ökosystemtypen mit unserer Methodik verglichen werden könnten.  相似文献   

9.
Refugia have been suggested as priority sites for conservation under climate change because of their ability to facilitate survival of biota under adverse conditions. Here, we review the likely role of refugial habitats in conserving freshwater biota in arid Australian aquatic systems where the major long‐term climatic influence has been aridification. We introduce a conceptual model that characterizes evolutionary refugia and ecological refuges based on our review of the attributes of aquatic habitats and freshwater taxa (fishes and aquatic invertebrates) in arid Australia. We also identify methods of recognizing likely future refugia and approaches to assessing the vulnerability of arid‐adapted freshwater biota to a warming and drying climate. Evolutionary refugia in arid areas are characterized as permanent, groundwater‐dependent habitats (subterranean aquifers and springs) supporting vicariant relicts and short‐range endemics. Ecological refuges can vary across space and time, depending on the dispersal abilities of aquatic taxa and the geographical proximity and hydrological connectivity of aquatic habitats. The most important are the perennial waterbodies (both groundwater and surface water fed) that support obligate aquatic organisms. These species will persist where suitable habitats are available and dispersal pathways are maintained. For very mobile species (invertebrates with an aerial dispersal phase) evolutionary refugia may also act as ecological refuges. Evolutionary refugia are likely future refugia because their water source (groundwater) is decoupled from local precipitation. However, their biota is extremely vulnerable to changes in local conditions because population extinction risks cannot be abated by the dispersal of individuals from other sites. Conservation planning must incorporate a high level of protection for aquifers that support refugial sites. Ecological refuges are vulnerable to changes in regional climate because they have little thermal or hydrological buffering. Accordingly, conservation planning must focus on maintaining meta‐population processes, especially through dynamic connectivity between aquatic habitats at a landscape scale.  相似文献   

10.
Freshwater fishes are an important but relatively little known component of the highly diverse fish fauna of Micronesia. Localities supporting communities of freshwater fishes include large high islands, with considerable habitat complexity, and smaller low islands, such as atolls and raised coral islands, with limited freshwater habitat. Both types of islands may support species with adult life history styles that are (a) amphidromous and catadromous, (b) euryhaline (often estuarine), or (c) marine species which enter freshwater from time to time. We compared patterns of species richness and similarity between Micronesian localities for amphidromous and catadromous, euryhaline and marine species (ACEM) pooled, and for amphidromous and catadromous species (ACFW). Species richness of both ACEM and ACFW fishes was greatest on larger high islands compared to smaller high and all low islands. Cluster analysis of similarity indices for ACEM species between localities revealed two faunal components: high islands and low islands. High islands were further partitioned into a Caroline Islands cluster and a separate Mariana Islands cluster. Cluster analysis of ACFW species was more complex. One cluster consisted of a low island and a small high island, both in the Carolines chain and with limited freshwater habitat. The second cluster was partitioned into high islands and low islands that reflected influences of both size and geographical location.  相似文献   

11.
生物多样性维护生态保护红线划定方法对比   总被引:3,自引:2,他引:3  
科学地评价区域内生物多样性维护功能重要性是生态保护红线划定中的重要环节,目前在生态保护红线划定导则中,推荐了NPP(净初级生产力,Net Primary Productivity)法和物种分布模型法,其中NPP法因其所需因子较少、计算简便得到广泛应用,物种分布模型法因所需因子较多、计算繁琐,应用较少。分别选用NPP法和MaxEnt(最大熵,Maximum Entropy)模型法对盘锦市生物多样性维护功能重要性进行评价,两种方法结果对比表明,NPP法无法覆盖全部的生物多样性重要区域,并且受农作物高NPP值的影响,其划定结果与鸟类实际分布范围不符,而MaxEnt模型法的结果更准确,与鸟类实际分布范围更相符,利用MaxEnt模型法最终得到盘锦市生物多样性维护生态保护红线面积1050.17km~2,占盘锦市陆域面积的25.85%,基本覆盖了境内东方白鹳、丹顶鹤、黑嘴鸥、震旦鸦雀等所有重点珍稀野生物种的栖息地和迁移路径的停歇地。本研究对生态保护红线划定工作具有重要的指导意义,其结果能为盘锦珍稀濒危鸟类的保护与管理提供科学支撑。  相似文献   

12.
刘焱序  傅伯杰  王帅  赵文武 《生态学报》2017,37(23):7761-7768
全球生态区划可以为全球和区域的生态系统保护与管理起到关键的空间指引作用,但当前全球生态区划方案存在重视生物地理分布特征而忽视生态系统服务的问题。系统梳理了全球生态区划研究进展,并总结为萌芽、发展和再认识的3个阶段。Bailey和Olson等的两套全球生态区划方案在近40年来使用最为广泛,但两套以生物多样性保护为区划目标的方案均属于生物地理区划范畴。为实现对区域生态安全保障和人地关系协调的全面支持,有必要开展以功能区划为主的全球生态区划研究,进一步完善生态区划理论体系、探索生态区划方法集成、突出生态系统服务权衡并聚焦人地关系动态演化。  相似文献   

13.
Rapid changes in species composition, also known as ecotones, can result from various causes including rapid changes in environmental conditions, or physiological thresholds. The possibility that ecotones arise from ecological niche construction by ecosystem engineers has received little attention. In this study, we investigate how the diversity of ecosystem engineers, and their interactions, can give rise to ecotones. We build a spatially explicit dynamical model that couples a multispecies community and its abiotic environment. We use numerical simulations and analytical techniques to determine the biotic and abiotic conditions under which ecotone emergence is expected to occur, and the role of biodiversity therein. We show that the diversity of ecosystem engineers can lead to indirect interactions through the modification of their shared environment. These interactions, which can be either competitive or mutualistic, can lead to the emergence of discrete communities in space, separated by sharp ecotones where a high species turnover is observed. Considering biodiversity is thus critical when studying the influence of species–environment interactions on the emergence of ecotones. This is especially true for the wide range of species that have small to moderate effects on their environment. Our work highlights new mechanisms by which biodiversity loss could cause significant changes in spatial community patterns in changing environments.  相似文献   

14.
Increasing anthropogenic impacts on biodiversity has been a cause for concern in Australia in recent years. Areas that hold high levels of endemic species and also face exceptional threats of destruction have been described as biodiversity hotspots. Ecological research focused on biodiversity hotspots will provide a better understanding of the flora and fauna of these regions and thus inform conservation strategies. Consequently, it is important to understand where biodiversity hotspots are located and how well they have been researched in the past. However, the choice of ecological research sites may be influenced by a variety of factors such as proximity to research institutions. This study utilized a geographic information system to investigate the spatial distribution of ecological research field sites in Australia and its territorial waters, the hotspots of the field sites around research institutions and the proximity of ecological research field sites from the main campus of the research institutions. Furthermore, these hotspots of ecological research were linked to biodiversity hotspots to identify the regions that were commonly depicted in the ecological literature and to identify others that may need more attention. We demonstrated that hotspots of ecological research were concentrated around research institutions, with a large number of field sites being located between 0 km and 500 km from the nearest institution, especially along the eastern coast. This study highlighted areas that have been the focus of much ecological research as well as areas that need more attention from ecologists to add new knowledge to Australian ecological science.  相似文献   

15.
粘液繁殖体及其生态功能   总被引:5,自引:0,他引:5  
马君玲  刘志民 《生态学杂志》2006,25(11):1400-1404
对粘液繁殖体的概念、粘液性质、粘液繁殖体的研究现状及粘液繁殖体研究中存在的问题进行了论述。分布在干旱区的十字花科、爵床科、菊科等植物具有粘液繁殖体。有关粘液繁殖体的研究集中在具有粘液繁殖体植物的识别、粘液形态结构及成分、粘液溶出机制及过程、粘液繁殖体的生态功能等几个方面。尽管已有研究表明,粘液繁殖体具有促进种子远距离传播、促进繁殖体的萌发及苗的发育、使种子免受摩擦损害和动物捕食等生态功能,但目前人们对粘液繁殖体的生态意义尚不十分清楚,从多物种比较研究中阐明粘液繁殖体生态意义的研究尚很少见。继续识别具有粘液繁殖体的植物,改善现有的研究手段,加强粘液繁殖体对植被恢复价值的研究是目前粘液繁殖体研究面临的挑战。  相似文献   

16.
姚保民  曾青  张丽梅 《生物多样性》2022,30(12):22353-254
原生生物广泛分布在土壤和不同生境中, 其数量庞大、种类繁多, 在生态系统物质循环和能量流动以及维持土壤和植物健康中起着举足轻重的作用。与土壤其他生物类群相比, 原生生物分类体系和生态类型复杂, 分类鉴定困难且分子检测技术不够成熟, 目前对原生生物的认识相对不足。本文对当前原生生物的相关研究进展进行了总结和梳理, 系统阐述了原生生物的分类系统和营养功能群特征、土壤原生生物的多样性分布特征及影响因子, 重点介绍了原生生物群落在参与土壤养分循环、维持土壤和植物健康等中的功能作用, 并对未来的研究方向与应用前景进行了展望。对土壤原生生物的研究有助于我们深入认识土壤生物多样性资源, 并进行保护性地开发和利用, 维护土壤和生态系统健康。  相似文献   

17.

Aim

Freshwater megafauna remain underrepresented in research and conservation, despite a disproportionately high risk of extinction due to multiple human threats. Therefore, our aims are threefold; (i) identify global patterns of freshwater megafauna richness and endemism, (ii) assess the conservation status of freshwater megafauna and (iii) demonstrate spatial and temporal patterns of human pressure throughout their distribution ranges.

Location

Global.

Methods

We identified 207 extant freshwater megafauna species, based on a 30 kg weight threshold, and mapped their distributions using HydroBASINS subcatchments (level 8). Information on conservation status and population trends for each species was extracted from the IUCN Red List website. We investigated human impacts on freshwater megafauna in space and time by examining spatial congruence between their distributions and human pressures, described by the Incident Biodiversity Threat Index and Temporal Human Pressure Index.

Results

Freshwater megafauna occur in 76% of the world’s main river basins (level 3 HydroBASINS), with species richness peaking in the Amazon, Congo, Orinoco, Mekong and Ganges‐Brahmaputra basins. Freshwater megafauna are more threatened than their smaller counterparts within the specific taxonomic groups (i.e., fishes, mammals, reptiles and amphibians). Out of the 93 freshwater megafauna species with known population trends, 71% are in decline. Meanwhile, IUCN Red List assessments reported insufficient or outdated data for 43% of all freshwater megafauna species. Since the early 1990s, human pressure has increased throughout 63% of their distribution ranges, with particularly intense impacts occurring in the Mekong and Ganges‐Brahmaputra basins.

Main conclusions

Freshwater megafauna species are threatened globally, with intense and increasing human pressures occurring in many of their biodiversity hotspots. We call for research and conservation actions for freshwater megafauna, as they are highly sensitive to present and future pressures including a massive boom in hydropower dam construction in their biodiversity hotspots.
  相似文献   

18.
我国西南喀斯特地区是具有土层薄和土被不连续等特征的生态脆弱区,人为过度干扰和土地不当利用导致了生境退化甚至石漠化的发生。从“九五”规划到“十三五”规划,为了有效抑制并逆转石漠化趋势,生态修复措施得到普遍的推广应用。“十四五”规划进一步提出科学推进石漠化综合治理,提高生态系统自我修复能力和稳定性。从土壤微生物、原生动物、线虫、微节肢动物、蚯蚓和线蚓等方面,综述了喀斯特地区生态修复对土壤生物多样性的影响。研究发现:(1)喀斯特生境细菌和真菌的多样性高于非喀斯特生境,原因是喀斯特具有较高的土壤pH和钙含量;(2)与非喀斯特生境相比,喀斯特生境土壤动物类群数相差不大而个体密度较低;(3)石漠化过程伴随着植被退化,降低了土壤微生物种类和功能多样性,土壤动物的个体密度和类群数也呈现降低趋势;(4)生态修复促进植被正向演替,土壤微生物量和酶类活性逐渐上升,真菌/细菌生物量比值增大,土壤动物个体密度和类群数增加,有利于土壤固碳和生态修复。因此,土壤生物多样性是适合指示喀斯特石漠化的生态修复的生物学指标。研究建议:(1)在传统分类鉴定基础上,结合宏基因组学、宏蛋白质组学和同位素标记等技术,完善生态修复的...  相似文献   

19.
Community ecology and ecosystem ecology provide two perspectives on complex ecological systems that have largely complementary strengths and weaknesses. Merging the two perspectives is necessary both to ensure continued scientific progress and to provide society with the scientific means to face growing environmental challenges. Recent research on biodiversity and ecosystem functioning has contributed to this goal in several ways. By addressing a new question of high relevance for both science and society, by challenging existing paradigms, by tightly linking theory and experiments, by building scientific consensus beyond differences in opinion, by integrating fragmented disciplines and research fields, by connecting itself to other disciplines and management issues, it has helped transform ecology not only in content, but also in form. Creating a genuine evolutionary ecosystem ecology that links the evolution of species traits at the individual level, the dynamics of species interactions, and the overall functioning of ecosystems would give new impetus to this much-needed process of unification across ecological disciplines. Recent community evolution models are a promising step in that direction.  相似文献   

20.
淡水生态系统中的TOP—DOWN效应与生物多样性保护   总被引:5,自引:0,他引:5  
淡水生态系统中高营养级类群可以对低营养级类群产生强烈的影响,最终导致整个生态环境的改变,这一现象被称作下行(topdown)效应。本文对topdown的含义特别是鱼类所产生topdown效应的结果进行了阐述,提出了topdown效应还表现在当原来生态系统中的高营养级类群缺少时,也会造成生态系统结构与功能发生变化的观点。最后,根据淡水生态系统topdown效应的特点,认为在淡水生态系统的生物多样性保护中,应注意高营养级类群的保护和谨慎地对待引种问题  相似文献   

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