Wide corridors with much environmental heterogeneity best conserve high dung beetle and ant diversity

Landscape ecological networks (ENs) consist of landscape-scale conservation corridors that connect areas of high natural value within a production mosaic with protected areas (PAs). In South Africa, ENs have been implemented on a large spatial scale to offset the negative impacts of plantation forestry on indigenous grasslands. We focus on corridor width as a factor for conserving dung beetle and ant diversity within an EN. We also investigate the importance of natural environmental heterogeneity (elevation, vegetation type) and habitat quality (soil hardness, invasive alien plant density). We sampled dung beetles and ants in 30 corridors of different sizes, and at ten sites in a nearby PA. In addition, we also analysed dung beetles according to their feeding guild. Tunnelling dung beetle species richness increased with corridor width. Rolling dung beetle species richness was higher in the PA than in the corridors of the EN. The dung beetle assemblage within the EN differed from that within the PA. Corridors of various widths differed in ant composition but not in species richness. Furthermore, the PA and the EN differed in environmental variables, which contributed to differences in dung beetle species richness and assemblage composition. Within the EN, environmental heterogeneity across the landscape was more important than corridor width for driving species diversity of both dung beetles and ants. When planning future ENs, wide corridors (>280 m) that encompass as much natural heterogeneity across the landscape as possible will best conserve the range of local insect species.     

Equivalence of grasslands in an ecological network and a World Heritage Site

Ecological networks (ENs) of indigenous vegetation among commercial forestry plantations have been implemented to offset the negative effects of the alien plantation trees on local biodiversity. However, it is not known whether these ENs are equivalent to protected areas (PAs) in terms of their grassland biodiversity. To address this knowledge gap, we investigated how well grassland plant species richness and composition in an EN corresponds to similar habitats in an adjacent PA. This took place in grasslands on the east coast of South Africa, and was done at four paired sites using ten replicates at each of the eight sites. Pairwise comparisons (EN vs. PA) of plant species composition yielded statistically smaller differences than comparisons between different pairs of sites within either the EN or PA, illustrating considerable turnover of species whether or not they were in an EN or PA. Overall, there were fewer plant species in the EN for three of the four pairs of sites. Nevertheless, plant species composition was similar in each pair of sites. The grassland EN was also characterized by greater maximum vegetation height and less green vegetation cover. When differences between the EN and a PA were viewed against the natural variation of abiotic and biotic conditions across the landscape, they were small. We conclude that ENs of natural habitat contribute substantially to biodiversity conservation in transformed, commercially-productive landscapes, are almost as good as PAs for maintaining grassland plant diversity.     

How to construct a coordinated ecological network at different levels: A case from Ningbo city,China

Constructing ecological networks (ENs) is an essential means to set up ecological cities and deliver sustainable development. However, there is a pressing need to address the lack of linkage between ENs at different administrative levels. Therefore, this paper takes Ningbo city as the study area and constructs ENs at the city and county levels with different indices and research methods. It explores the linkages between ecological source areas and corridors at various administrative levels, finally forming an EN that links multiple levels. The results of the study show that 19 ecological source areas of approximately 1534.18 km² and 22 ecological corridors of 455.85 km were identified in the city of Ningbo. Furthermore, 12 ecological source areas, 16 natural ecological corridors, and 10 cultural landscape corridors were identified in Ningbo's Zhenhai District. After the superposition of municipal ecological sources, Zhenhai's ecological source areas increased in the west, north and southeast, adding approximately 12.81 km². Based on the comprehensive resistance surface, 18 composite ecological corridors were extracted, occupying approximately 74.21 km. After joining different administrative levels, the overall connectivity increased, promoting the circulation of ecosystem services. This study can accurately identify the spaces with critical ecological roles at different administrative levels and provide a reference for designing the whole ecological space and carrying out top-down ecological restoration projects.     

Conservation of Flower-arthropod Associations in Remnant African Grassland Corridors in an Afforested Pine Mosaic

While there has been much debate on the role of landscape corridors or linkages for animal movement and residency, there is little information on their role in maintaining ecological associations. We assess here the arthropod assemblages on flowers, seed heads and leaves of indigenous plants in a network of remnant grassland corridors across an alien pine-planted landscape in southern Africa. The results showed that the arthropod-plant (flowers, seed heads and leaves) associations remained, and were mostly quantitatively similar throughout the network of corridors. Narrow corridors (20–100 m wide) deep within the plantation-grassland mosaic still had high biodiversity value. The most threatening factor to flower-arthropod associations was disturbance, particularly cattle grazing. That the host plants were actually present was, in itself, an indicator that disturbance nevertheless was low. The associations are only lost when the plants are lost, and not when the plants are present but under some disturbance pressure. Although these corridors, which amount to about a third of the total area, mitigate the effects of pine afforestation, they can also be conduits for heavy human impact. This means that these corridors, even narrow and deep ones, are only of maximum value when there is minimal anthropogenic impact.     

Multiple facets of stream macroinvertebrate alpha diversity are driven by different ecological factors across an extensive altitudinal gradient

Environmental filtering and spatial structuring are important ecological processes for the generation and maintenance of biodiversity. However, the relative importance of these ecological drivers for multiple facets of diversity is still poorly understood in highland streams. Here, we examined the responses of three facets of stream macroinvertebrate alpha diversity to local environmental, landscape‐climate and spatial factors in a near‐pristine highland riverine ecosystem. Taxonomic (species richness, Shannon diversity, and evenness), functional (functional richness, evenness, divergence, and Rao's Quadratic entropy), and a proxy of phylogenetic alpha diversity (taxonomic distinctness and variation in taxonomic distinctness) were calculated for macroinvertebrate assemblages in 55 stream sites. Then Pearson correlation coefficient was used to explore congruence of indices within and across the three diversity facets. Finally, multiple linear regression models and variation partitioning were employed to identify the relative importance of different ecological drivers of biodiversity. We found most correlations between the diversity indices within the same facet, and between functional richness and species richness were relatively strong. The two phylogenetic diversity indices were quite independent from taxonomic diversity but correlated with functional diversity indices to some extent. Taxonomic and functional diversity were more strongly determined by environmental variables, while phylogenetic diversity was better explained by spatial factors. In terms of environmental variables, habitat‐scale variables describing habitat complexity and water physical features played the primary role in determining the diversity patterns of all three facets, whereas landscape factors appeared less influential. Our findings indicated that both environmental and spatial factors are important ecological drivers for biodiversity patterns of macroinvertebrates in Tibetan streams, although their relative importance was contingent on different facets of diversity. Such findings verified the complementary roles of taxonomic, functional and phylogenetic diversity, and highlighted the importance of comprehensively considering multiple ecological drivers for different facets of diversity in biodiversity assessment.     

湖南省城市群生态网络构建与优化

大型生境斑块为区域生物多样性保护提供了重要的空间保障。然而,快速城市化使得大型生境斑块变得日益破碎化、岛屿化,连接性不断下降,且日益受到周边土地利用变化的强烈影响,已严重威胁着区域生物多样性的保护。通过生态廊道建立或修复破碎生境斑块之间的连接,将非常有利于生态网络生态服务功能的有效发挥。基于景观生态学和保护生物学的相关原理,以湖南省城市群为例,在RS和GIS技术的支撑下,采用最小费用路径和情景分析方法,定量模拟了研究区的潜在生态廊道,基于重力模型对重要生态廊道进行了识别与提取,并就消费面模型对潜在生态网络结果产生的影响进行了分析,在此基础上有针对性地提出了生态网络优化的对策。研究结果表明,林地和耕地是组成研究区生态网络的优势景观要素类型;不同生境斑块间的相互作用强度差异显著,总体上西高东低,南高北低;消费面模型能够在较大程度上影响到生态网络的分析结果,因而进行情景分析十分重要和必要。研究结果可为研究区生态网络的构建和优化提供科学依据,同时可为其他城市群区域生态网络的构建提供参考和借鉴。     

基于生态供需视角的生态安全格局构建与优化——以长三角地区为例

生态安全格局构建是保障区域生态安全与提升人类福祉的基本途径之一。以长三角地区为案例区,通过生境质量评估、生态系统服务重要性评价和景观连通性分析识别区域生态源地,在利用生态系统服务价值化方法辨别高生态需求区的基础上,运用最小累积阻力模型提取源地与高需求地之间的生态廊道,以构建并优化区域生态安全格局。研究结果表明:长三角地区生态源地总面积64911km~2,占全区的32.51%,主要分布于皖南和浙中;区域中高与较高生态需求斑块总面积占全区46.60%,主要位于上海市和江苏省;区域生态廊道总长度11188.85km,源间廊道主要分布于长江沿岸和区域南部,需求廊道主要位于区域东中北部。研究首次将生态需求评价纳入生态廊道建设框架,为生态安全格局构建提供新思路,结果可为生态空间保护规划提供参考。     

中-老交通走廊核心区生态廊道构建与关键节点识别

中-老交通走廊建设在促进中国与东盟国家互联互通的同时,也会对区域生态安全造成巨大压力;构建生态廊道对于修复破碎景观、保护生物多样性具有十分重要的意义。基于"源地-廊道-节点"的研究框架,结合生态系统服务、景观连通性和生态敏感性3个指标划分生态斑块等级,综合考虑生态斑块等级和中-老交通走廊核心区重点保护物种活动特性识别重要生态源地,利用DMSP/OLS夜间灯光数据改进基于地类赋值的基本生态阻力系数,运用最小累积阻力模型判定生态廊道走向,并结合水文分析方法和Google Erath判定关键生态节点。研究表明:①中-老交通走廊核心区生态源地面积为20243.74 km~2,占研究区总面积的14.13%,以林地、灌木为主要土地覆被类型,主要分布在云南省的普洱市以及老挝的琅南塔省和乌多姆塞省。②生态廊道总长度为3645.81 km,其中关键廊道长度为1397.78 km,主要分布在普洱市和乌多姆塞省,生态廊道与生态源地大致构成了一个环形闭合区域,能够有效促进生物物种迁徙和物质能量交流。③关键生态节点中战略点有5处,断裂点有9处,暂歇点有16处。     

Landscape moderation of biodiversity patterns and processes - eight hypotheses

Understanding how landscape characteristics affect biodiversity patterns and ecological processes at local and landscape scales is critical for mitigating effects of global environmental change. In this review, we use knowledge gained from human-modified landscapes to suggest eight hypotheses, which we hope will encourage more systematic research on the role of landscape composition and configuration in determining the structure of ecological communities, ecosystem functioning and services. We organize the eight hypotheses under four overarching themes. Section A: 'landscape moderation of biodiversity patterns' includes (1) the landscape species pool hypothesis-the size of the landscape-wide species pool moderates local (alpha) biodiversity, and (2) the dominance of beta diversity hypothesis-landscape-moderated dissimilarity of local communities determines landscape-wide biodiversity and overrides negative local effects of habitat fragmentation on biodiversity. Section B: 'landscape moderation of population dynamics' includes (3) the cross-habitat spillover hypothesis-landscape-moderated spillover of energy, resources and organisms across habitats, including between managed and natural ecosystems, influences landscape-wide community structure and associated processes and (4) the landscape-moderated concentration and dilution hypothesis-spatial and temporal changes in landscape composition can cause transient concentration or dilution of populations with functional consequences. Section C: 'landscape moderation of functional trait selection' includes (5) the landscape-moderated functional trait selection hypothesis-landscape moderation of species trait selection shapes the functional role and trajectory of community assembly, and (6) the landscape-moderated insurance hypothesis-landscape complexity provides spatial and temporal insurance, i.e. high resilience and stability of ecological processes in changing environments. Section D: 'landscape constraints on conservation management' includes (7) the intermediate landscape-complexity hypothesis-landscape-moderated effectiveness of local conservation management is highest in structurally simple, rather than in cleared (i.e. extremely simplified) or in complex landscapes, and (8) the landscape-moderated biodiversity versus ecosystem service management hypothesis-landscape-moderated biodiversity conservation to optimize functional diversity and related ecosystem services will not protect endangered species. Shifting our research focus from local to landscape-moderated effects on biodiversity will be critical to developing solutions for future biodiversity and ecosystem service management.     

Aquatic biodiversity in forests: a weak link in ecosystem services resilience

The diversity of aquatic ecosystems is being quickly reduced on many continents, warranting a closer examination of the consequences for ecological integrity and ecosystem services. Here we describe intermediate and final ecosystem services derived from aquatic biodiversity in forests. We include a summary of the factors framing the assembly of aquatic biodiversity in forests in natural systems and how they change with a variety of natural disturbances and human-derived stressors. We consider forested aquatic ecosystems as a multi-state portfolio, with diverse assemblages and life-history strategies occurring at local scales as a consequence of a mosaic of habitat conditions and past disturbances and stressors. Maintaining this multi-state portfolio of assemblages requires a broad perspective of ecosystem structure, various functions, services, and management implications relative to contemporary stressors. Because aquatic biodiversity provides multiple ecosystem services to forests, activities that compromise aquatic ecosystems and biodiversity could be an issue for maintaining forest ecosystem integrity. We illustrate these concepts with examples of aquatic biodiversity and ecosystem services in forests of northwestern North America, also known as Northeast Pacific Rim. Encouraging management planning at broad as well as local spatial scales to recognize multi-state ecosystem management goals has promise for maintaining valuable ecosystem services. Ultimately, integration of information from socio-ecological ecosystems will be needed to maintain ecosystem services derived directly and indirectly from forest aquatic biota.     

综合模型法评估黄河三角洲湿地景观连通性

景观连通性是区域生态系统功能完整的重要表征。连通性的评估对生态系统管理和保护规划有重要意义。综合常用的景观连通性评估模型,即最小耗费距离模型与电路理论模型,根据生态网络构建的一般范式,采取两种不同阻力面赋值方案,对黄河三角洲的湿地景观连通性进行评估,并对比分析了两种模型的基本原理、工作性能、分析尺度等。结果表明：最小耗费距离模型能够识别最优生态廊道,为景观连通性评估提供基本模式。电路理论则能扩展到潜在生态廊道和关键生态点的量化识别,能确定具有生态功能的“夹点”和障碍区的空间位置。综合两种模型,可以量化评估黄河三角洲湿地景观连通性,空间化三角洲湿地保护恢复的管理目标,即潜在廊道和关键生态节点,为区域生态系统功能评估和管理提供精准的数据支持。     

生物多样性保护廊道构建方法研究进展

生物多样性保护廊道对遏制生态系统退化及生物多样性丧失,改善生态系统服务功能,消除生境破碎化对生物多样性的影响,恢复珍稀濒危物种的种群数量,维护自然生态系统平衡稳定具有极为重要的作用。在近20年(1997—2017)国内外生物多样性保护廊道的相关研究分析的基础上,对廊道的概念、构建理论及方法应用进行了系统总结与探讨,分析了廊道构建理论的发展过程及适用性,分类总结了现有的廊道构建方法和17种廊道构建模型工具。研究分析表明,廊道作为一种新的生物多样性保护模式,已成为目前国际生态领域研究的热点之一,随着对物种景观运动过程认识的加深,廊道构建理论逐渐趋于成熟,与之匹配的廊道构建方法及模型工具进展迅速。借助遥感与地理信息技术,大范围,高精度的获取廊道模拟数据,并集成综合模型实现目标物种廊道的构建、保护和管理是今后生物多样性保护廊道构建研究的发展方向。最后,对当前该领域的研究现状和不足展开讨论并展望了未来发展,为我国生物多样性保护廊道的应用与实践及国家生态廊道体系的建设完善提供借鉴与参考。     

江苏省自然遗产地生态网络的构建与优化

自然遗产地是生物的重要栖息场所,而生态网络是连接自然遗产地的有效途径,如何有效和合理地构建自然遗产地之间的生态廊道,连接破碎生境,对保护自然遗产地生物多样性和区域生态安全具有重要意义。在Arc GIS 9.3的技术支持下,通过合理估算阻力阈值,采用最小耗费距离模型分析方法,构建江苏省省域范围内的自然遗产地生态网络保护体系,并在网络连通性指数分析方法的基础上对生态网络的连通性和有效性进行评价,针对性地提出自然遗产地生态网络的优化措施。研究结果表明:78.28%的林地、88.70%的滩涂滩地、94.37%的草地是自然遗产地生态网络的主要景观组成结构;自然遗产斑块本身对生态网络的构建有较大影响,其中面积较大、长条型的斑块对维持景观连通性的重要性程度贡献较大;研究区现状整体生态连通性指数仅0.001—0.003,连通性水平较差,通过构建生态网络,整体连通性水平可提高到0.044—0.046,可能连通性水平可达到0.074,表明自然遗产廊道的构建可提高景观的连通性水平;在现有生态网络结构的基础上,增加破碎斑块间的生态连接是优化生态网络体系的可行性策略。     

Growing biodiverse carbon‐rich forests

Regrowing forests on cleared land is a key strategy to achieve both biodiversity conservation and climate change mitigation globally. Maximizing these co‐benefits, however, remains theoretically and technically challenging because of the complex relationship between carbon sequestration and biodiversity in forests, the strong influence of climate variability and landscape position on forest development, the large number of restoration strategies possible, and long time‐frames needed to declare success. Through the synthesis of three decades of knowledge on forest dynamics and plant functional traits combined with decision science, we demonstrate that we cannot always maximize carbon sequestration by simply increasing the functional trait diversity of trees planted. The relationships between plant functional diversity, carbon sequestration rates above ground and in the soil are dependent on climate and landscape positions. We show how to manage ‘identities’ and ‘complementarities’ between plant functional traits to achieve systematically maximal cobenefits in various climate and landscape contexts. We provide examples of optimal planting and thinning rules that satisfy this ecological strategy and guide the restoration of forests that are rich in both carbon and plant functional diversity. Our framework provides the first mechanistic approach for generating decision‐makingrules that can be used to manage forests for multiple objectives, and supports joined carbon credit and biodiversity conservation initiatives, such as Reducing Emissions from Deforestation and forest Degradation REDD+. The decision framework can also be linked to species distribution models and socio‐economic models to find restoration solutions that maximize simultaneously biodiversity, carbon stocks, and other ecosystem services across landscapes. Our study provides the foundation for developing and testing cost‐effective and adaptable forest management rules to achieve biodiversity, carbon sequestration, and other socio‐economic co‐benefits under global change.     

Grasshopper and butterfly local congruency in grassland remnants

Grasshoppers could be considered as appropriate ecological indicators for grasslands owing to their sensitive response to environmental features. However, if grasshoppers are a good ecological indicator, they must (i) also represent other taxa, and (ii) provide additional information over straight measurement of environmental variables. To assess this, we compared the congruence of species richness patterns of grasshoppers with butterflies and environmental variables in two areas with extensive ecological networks (ENs). ENs are landscape-scale remnants of corridors and nodes of natural habitat running throughout a transformed, usually agricultural, landscape. Species richness of grasshoppers and butterflies did not differ among reference and EN sites, but guild composition differed significantly. While ENs adequately conserved overall diversity of these two groups, they were utilized preferentially by small-sized grasshoppers and shrub and tree-feeding butterflies. Reference sites had significantly more graminivorous and intermediate-mobility grasshopper species, as well as more butterfly species with widespread distribution, herbaceous dicot feeders and those with no recorded association to forest edges. Nevertheless, grasshopper and butterfly species richness’ were highly correlated. These results were similar across geographic areas, despite the fact that the areas differed significantly in their overall richness and species composition. Although there were some specific significant correlations between environmental variables and diversity, none of the variables could adequately replace use of the insect assemblage for bioindication. We conclude that grasshopper species and guild richness are representative of the butterfly assemblage, and provide information which is not sufficiently clear when utilizing only environmental variables.     

景观生态学与生物多样性保护

景观生态学的发展为生物多样性保护提供了新理论,方法和技术手段,从景观多样性与遗传多样性,物种多样性,生态系统多样性各层次生物多样性之间的相互关系及生物多样性保护的景观规划等方面评述近年来景观生态学应用于生物多样性保护的主要内容及研究进展,阐述了生物多样性动态及反馈,生物多样性保护的地理途径（ＧＡＰ分析）,景观生态安全格局,区域和大陆尺度的生态网络等一些新的概念和方法。     

The fauna of dynamic riverine landscapes

1.  Riverine landscapes are heterogeneous in space (complex mosaic of habitat types) and time (expansion and contraction cycles, landscape legacies). They are inhabited by a diverse and abundant fauna of aquatic, terrestrial and amphibious species.
2.  Faunal distribution patterns are determined by interactive processes that reflect the landscape mosaic and complex environmental gradients. The life cycles of many riverine species rely upon a shifting landscape mosaic and other species have become adapted to exploit the characteristically high turn-over of habitats.
3.  The complex landscape structure provides a diversity of habitats that sustains various successional stages of faunal assemblages. A dynamic riverine landscape sustains biodiversity by providing a variety of refugia and through ecological feedbacks from the organisms themselves (ecosystem engineering).
4.  The migration of many species, aquatic and terrestrial, is tightly coupled with the temporal and spatial dynamics of the shifting landscape mosaic. Alternation of landscape use by terrestrial and aquatic fauna corresponds to the rise and fall of the flood. Complex ecological processes inherent to intact riverine landscapes are reflected in their biodiversity, with important implications for the restoration and management of river corridors.     

Riverine landscape diversity

1. This review is presented as a broad synthesis of riverine landscape diversity, beginning with an account of the variety of landscape elements contained within river corridors. Landscape dynamics within river corridors are then examined in the context of landscape evolution, ecological succession and turnover rates of landscape elements. This is followed by an overview of the role of connectivity and ends with a riverine landscape perspective of biodiversity. 2. River corridors in the natural state are characterised by a diverse array of landscape elements, including surface waters (a gradient of lotic and lentic waterbodies), the fluvial stygoscape (alluvial aquifers), riparian systems (alluvial forests, marshes, meadows) and geomorphic features (bars and islands, ridges and swales, levees and terraces, fans and deltas, fringing floodplains, wood debris deposits and channel networks). 3. Fluvial action (erosion, transport, deposition) is the predominant agent of landscape evolution and also constitutes the natural disturbance regime primarily responsible for sustaining a high level of landscape diversity in river corridors. Although individual landscape features may exhibit high turnover, largely as a function of the interactions between fluvial dynamics and successional phenomena, their relative abundance in the river corridor tends to remain constant over ecological time. 4. Hydrological connectivity, the exchange of matter, energy and biota via the aqueous medium, plays a major though poorly understood role in sustaining riverine landscape diversity. Rigorous investigations of connectivity in diverse river systems should provide considerable insight into landscape‐level functional processes. 5. The species pool in riverine landscapes is derived from terrestrial and aquatic communities inhabiting diverse lotic, lentic, riparian and groundwater habitats arrayed across spatio‐temporal gradients. Natural disturbance regimes are responsible for both expanding the resource gradient in riverine landscapes as well as for constraining competitive exclusion. 6. Riverine landscapes provide an ideal setting for investigating how complex interactions between disturbance and productivity structure species diversity patterns.     

Ecosystem services provided by semi-natural and intensified grasslands: Synergies,trade-offs and linkages to plant traits and functional richness

Question

Semi-natural grasslands (SNG) are important for maintaining biodiversity and ecological processes in farmland. Current pasture-based livestock production mainly occurs on intensified grasslands (IG) that have been agronomically improved. Although it is documented that SNG and IG differ in terms of plant diversity, their ability to provide ecosystem services (ES) in farmland is less explored. Here, we review the role of SNG and IG in delivering ES, illustrate their trade-offs and synergies, and examine how ES can be assessed by using plant traits and functional richness.

Results

We found that SNG generate a wider range of ES than IG. Trade-offs exist between ES that appear more pronounced in IG between high biomass production and other ES. SNG are good in providing habitat for biodiversity, supporting pollination and cultural services. SNG also have a significantly wider range of plant functional traits and a higher functional richness, suggesting that the potential to supply ES in SNG is partly driven by higher number of species and their functional diversity.

Conclusion

Clearer trade-offs were found in IG compared with SNG, supported both by the literature and the functional richness. This suggests that functional knowledge could be a good complement to understand the mechanisms behind ES generation and could help with tailoring grassland management to sustain biodiversity, ecological functions and ES. Although both IG and SNG are likely needed for the long-term sustainability of food production, both could aim for a more balanced generation of ES, increasing biodiversity and functional redundancy at the landscape scale.     

中国西南纵向岭谷区外来入侵植物对生物多样性的影响

论述中国西南纵向岭谷区外来入侵植物对生物多样性的影响。中国西南纵向岭谷区是我国生物多样性保护的关键地区。目前,该区域已成为外来植物入侵的重灾区,外来入侵植物种类多达70余种,其中,紫茎泽兰Ageratina adenophora（Eupatoriumadenophorum）、飞机草Chromolaena odorata（Eupatorium odoratum）和肿柄菊Tithonia diversifolia等在该区域危害严重,该区域的生态系统的结构与功能遭受破坏,本地物种面临灭绝,农、林、牧生产乃至区域的生态安全受到威胁。该区域的外来入侵植物的危害居全国之冠。研究该区域的外来入侵植物,揭示其危害规律,遏制其危害速度,最终清除该区域的外来入侵植物,恢复该区域的生态平衡,具有十分重要的现实意义和科学价值。文中详细论述了外来入侵植物对植物物种多样性、植物群落多样性、生态系统多样性、农牧业及林业的影响,最后指出消除和控制外来入侵植物的途径。