农业景观步甲多样性时间格局及其与景观结构的关系

于2009年5-9月在北京密云县采用陷阱法对玉米地、花生地、果园和林地4种生境中步甲群落进行取样,并采用逐步线性回归分析了景观中优势生境类型——玉米地中步甲群落及其捕食性步甲功能群多样性的季节分布,及其与周围100、250和500 m半径范围内景观格局指数的关系.结果表明:不同生境下,8月步甲群落、捕食性步甲类群的个体数和物种数均达到最大;5月玉米地中步甲群落的物种数与取样点100 m半径范围内的景观连接度呈正相关,8月步甲群落个体数和500 m半径范围内的景观连接度呈负相关;5月玉米地中捕食性步甲群落不论是个体数还是物种数均与取样点100 m半径范围内景观连接度呈正相关,而8月捕食性步甲的物种数则与100 m尺度范围内的半自然生境的类型数呈负相关.可见,景观连接度、半自然生境的类型数对步甲及其中捕食性步甲群落动态的关键季节的多样性状况有显著影响,合理规划农田半自然用地类型组成、增加景观连接度可促进步甲群落多样性保护及其害虫生物控制功能的发挥.     

半自然农田边界与相邻农田步甲和蜘蛛的时空分布

分别于小麦、玉米收获前后,采用陷阱法调查了华北地区典型农业景观中具有不同植被结构的农田边界及其相邻农田中两类重要天敌类群步甲和蜘蛛的多样性.通过比较农田生境及相邻农田边界间两类天敌群落的时空分布格局及其与相邻半自然生境植被群落的相关关系,探讨半自然农田边界对两类天敌类群的保护作用.结果表明: 整个取样季节农田边界处蜘蛛的多度显著高于农田内部;而步甲多样性在农田与边界间无显著性差异,仅呈现不同的群落结构;作物收获后蜘蛛分科数在边界处的增加以及在农田的减少,显示了蜘蛛在农田和边界之间的迁移活动.边界植被结构对蜘蛛和步甲多样性有不同影响:边界较高的草本层盖度和较低的乔木层盖度有利于增加农田中某些步甲优势种的多样性;而较高的草本层盖度有利于增加皿蛛科蜘蛛的多样性.因此,半自然生境的存在可以通过天敌在农田和边界之间的迁移运动促进农田天敌多样性的维持;但不同类型半自然生境植被群落结构可能影响其对不同天敌群落多样性的维持和保护作用.为促进农业景观对天敌的保护作用,提高其害虫控制功能,需要深入了解不同天敌的生境需求及食物需求,精心设计有利于天敌多样性维持的半自然生境.     

坝上地区不同海拔农田和恢复半自然生境下尺蛾多样性

为研究生境恢复及地形变化导致的景观异质性对退化景观中生物多样性的影响,于2006和2007年对河北坝上3个不同海拔村庄的农田生境与恢复中的禁牧草地或再造林等半自然生境的尺蛾群落采用灯诱法进行取样调查,比较不同生境的尺蛾多样性.结果表明： 两种生境类型间物种数和个体数存在显著差异、不同海拔村庄物种数也存在显著差异,但不同海拔村庄间个体数差异不显著,不同海拔村庄间以及各村庄内农田和半自然生境稀疏标准化物种数和Fisher α指数无显著差异;非度量多维标度法(NMDS)显示不同海拔的不同生境下尺蛾群落结构显著不同.地形变化导致的景观异质性对坝上地区尺蛾群落组成及多样性影响显著,而无论是恢复中的草地、再造林等半自然生境还是农田生境均是维持尺蛾多样性的重要生境.注重不同地形条件下农田生境和半自然生境景观镶嵌体的保护对维持尺蛾群落γ多样性具有重要意义,但生境恢复能否促进尺蛾群落多样性恢复尚需长期监测.     

黄河下游平原农业景观中非农生境植物多样性

农业景观中的自然、半自然生境及其上的植物群落对维持农业生态系统功能意义重大。为了解黄河下游典型平原农业景观中非农生境植物多样性特征,在对研究区景观格局分析的基础上,使用典型样地法对区域内农业景观中主要自然、半自然生境(包括林地、树篱、田间道路、沟渠等)进行调查。结果显示:研究区总体上为农业景观,居民点和林地斑块散布其间;区内植物科的地理分布以世界分布和泛热带分布为主,属的地理成分复杂,具有中国15个种子植物属分布区类型中的13个,以温带分布、世界分布和泛热带分布为主,总体上以广布种为主,优势科属明显,缺少特有种;林地和树篱具有较高的物种丰富度和多样性,沟渠和林地的物种均匀度和群落盖度最高,田间道路上群落组成的变化幅度和分化程度最大(β多样性指数最高);林地、树篱和田间道路等生境间的群落相似性极高,但其群落盖度和优势种组成具有显著差异,沟渠作为一种特殊生境与其他生境间相似性较低。研究表明,在黄河下游平原农业景观中,林地和树篱在物种多样性维持中作用较大,沟渠为水生和湿生植物提供了庇护所,不同生境间极高的群落相似性仅是物种组成名录的反映,而其生态功能存在显著差异。未来区内的生物多样性保护应重在生态系统功能和服务的维持及提高,而如何进行景观要素配置,才能兼顾农业生产力的可持续性和生态系统功能维持,尚需进一步探讨。     

不同农业景观背景下传粉昆虫群落的分布差异

农业景观中的自然、半自然生境等非农生境可为传粉昆虫提供丰富的食物来源、栖息地、繁殖地、避难所等,对维持生物多样性的稳定起着不可替代的作用。以巩义典型的山地-丘陵-河川混杂的复杂景观和民权的平原农业简单景观为研究区,分析不同景观背景下传粉昆虫群落的物种组成及其在不同生境中的分布特征。结果表明:(1)巩义研究区内累计捕获传粉昆虫18582头,民权研究区内累计捕获传粉昆虫18518头,优势传粉昆虫功能群为双翅目、膜翅目、鞘翅目和鳞翅目等;(2)景观复杂度更高的巩义研究区的传粉昆虫多样性、丰富度以及均匀度均显著高于民权研究区;存在大面积农田斑块的平原景观中则有更多的优势传粉昆虫个体;(3)农田斑块中具有更高的物种丰富度,但林地物种的多样性和均匀度则相对稍高些。农田斑块在作物花期能有效的提高传粉者种群密度,但林地等自然、半自然生境对于维持传粉者多样性和食物缺乏期种群的稳定具有重要作用。因此在未来为确保农业景观中传粉者的多样性与传粉服务的稳定,一方面要关注自然、半自然生境的作用,同时也要考虑不同景观背景下异质性特征对不同生物类群的影响差异。     

农业景观生物多样性与害虫生态控制

现代农业的一个重要特征就是人类对农田生态系统的干扰强度及频率不断增加,严重影响农业景观的结构及其生物多样性.农业景观结构的变化及其生物多样性的丧失,必然引起生态系统服务功能的弱化,不利于实施以保护自然天敌为主的害虫生态控制.农业的集约化经营导致自然生境破碎化,减少了农业景观的复杂性,使得作物和非作物变成一种相对离散化的生境类型和镶嵌的景观格局;破碎化的生境不仅会减少某些物种的丰度,还会影响物种之间的相互关系及生物群落的多样性和稳定性.非作物生境类型如林地、灌木篱墙、田块边缘区、休耕地和草地等,是一种比较稳定的异质化环境.非作物生境较少受到干扰,可以为寄生性和捕食性节肢动物提供适宜的越冬或避难场所以及替代猎物、花粉和花蜜等资源,因此,非作物生境有利于自然天敌的栖息和繁衍,也有利于它们迁入邻近的作物生境中对害虫起到调节和控制作用.景观的格局-过程-尺度影响农田生物群落物种丰富度、多度、多样性以及害虫与天敌之间的相互作用.从区域农业景观系统的角度出发,运用景观生态学的理论和方法来研究作物、害虫、天敌等组分在不同斑块之间的转移过程和变化规律,揭示害虫在较大尺度和具有异质性的空间范围内的灾变机理,可为利用农业景观生物多样性来保护农田自然天敌,实施害虫的区域性生态控制提供新的研究思路和手段.     

黄河下游平原不同非农生境中植物多样性

自然、半自然等非农生境是区域农业景观的重要组成部分,对区域生物多样性保护具有重要意义。黄河下游平原区是典型的农业景观,农田是最主要的景观类型,林地、树篱等景观要素散布其中,为研究区内非农生境中生物多样性及其生态效应,采用典型样地法对区内典型农业景观中林地、树篱、田间道路和沟渠等主要非农生境中的植物群落进行调查研究。结果显示:区内植物组成以菊科、禾本科等为主;区内植物科的地理成分以世界分布和泛热带分布为主,各生境间有一定的差异,属的地理成分复杂,具有中国15个种子植物属分布型中的13个,以温带分布、世界分布和泛热带分布为主,总体上区内的植物组成以广布种为主,优势科属明显,特有种缺乏;各非农生境中的植物多样性存在一定的差异,林地和树篱生境具有较高的物种丰富度和多样性,显著高于田间道路,沟渠、林地和树篱生境中的物种均匀度和群落盖度均显著高于田间道路;β多样性分析表明田间道路生境中的群落组成分化程度在各样点间最大(β多样性指数最高);树篱、林地和田间道路等生境间群落相似性均较高,但其群落结构和优势种组成方面却存在显著的差异,沟渠作为一种特殊生境与其它生境间的群落相似性相对较低。研究表明,在黄河下游平原典型农业景观中,作为非农生境存在的林地和树篱在物种多样性维持中具有重要地位,沟渠为水生和湿生植物提供了庇护所,意义重大;各生境间高的群落相似性仅是物种组成名录相似性的反映,其空间格局和优势种群间差异明显,各生境植物群落的生态功能差异巨大。未来区内生物多样性的保护应重在生态系统过程、功能的加强以及生态系统服务的维持和提高,且需进一步在景观水平上探讨各非农景观要素的空间构型对其生态效益的影响机制及其调控和管理策略。     

坝上地区农田和恢复生境地表甲虫多样性

研究采用陷阱法对河北坝上崇礼县农田、禁牧草地及再造林地3种常见生境中地表甲虫进行了取样调查,分别从鞘翅目分科、步甲分种两个分类水平比较分析了不同生境中的生物多样性状况以评估生境恢复状况及其对生物多样性的影响,并探索在以生物多样性为指标评估生境恢复状况过程中,研究结论是否受分类水平的影响。结果显示,草地和林地具有较为相似鞘翅目和步甲的结构组成,但均显著不同于农田。农田较再造林地和禁牧草地具有更多的鞘翅目科数及步甲物种数,且均显著高于林地;农田中步甲群落的Fisher's α多样性指数也显著地高于林地,但鞘翅目分科水平上的Fisher's α多样性指数在各生境中没有差异。结果说明:(1)再造林和草地禁牧的生境修复活动在当前状态下对生物多样性恢复的作用尚不明显,仅是表现出促进了景观尺度上较高的Beta和Gamma多样性,而农田则在维持当地较高的生物多样性中扮演重要角色;(2)在鞘翅目分科和步甲科分种研究数据所反映的不同生境条件下的多样性和组成状况基本相同,因此在需要快速评估生境恢复状况且物种水平鉴定存在困难的时候,可以采用鞘翅目分科的数据替代指示生境恢复的状况并反映生境恢复对生物多样性影响的趋势,从而减少分类的难度并提高工作效率。但是物种水平的多样性状况更能显著反映生境间的差异。     

植被边界带对相邻麦田地表步甲和蜘蛛分布及蚜虫发生的影响

通过管理半自然生境提高农田中天敌多样性及农田害虫的生物控制效率是当前生态农业研究的基本问题之一。为探讨不同类型半自然植被边界带对相邻麦田地表天敌的发生以及对小麦蚜虫生物控制潜力的影响,在北京顺义区赵全营镇采用陷阱法调查了不同类型植被边界带（人工林地、人工种植草带、自然演替草带）相邻的小麦田中,距离边界0,15 m和30 m处步甲和蜘蛛两类重要地表天敌的多度分布及小麦田蚜虫发生情况,同时分析了边界带植被群落结构对步甲和蜘蛛群落分布的影响。结果表明：人工林地相邻的小麦田中维持了显著较高的步甲、蜘蛛和蚜虫发生密度;不同类型植被边界带相邻小麦田中步甲和蜘蛛群落组成显著不同,植被边界带宽度以及乔木层盖度是影响相邻麦田步甲和蜘蛛群落分布的主要因子;距离植被边界带不同取样界面处,不同迁移方向的步甲和蜘蛛的活动密度无显著性差异;与林地相邻的麦田中,蜘蛛活动密度从农田边界向农田内部处依次降低,与人工种植草带以及自然演替草带相邻的麦田中,农田边界处蜘蛛的活动密度显著高于农田内部。研究显示,半自然植被边界带与麦田交界处维持了较高的蜘蛛活动密度,并具有向农田内部扩散的趋势,然而,并非高天敌密度就意味着低害虫发生率,深入研究天敌群落与害虫发生关系及其影响因素是未来天敌保护和害虫生物防治的重要方面。同时,因为不同类型植被边界带维持的天敌群落具有高度异质性,未来的研究需要充分考虑不同类型植被边界带对天敌维持的作用,以及不同类型生境界面地表天敌的活动规律。     

北京东北旺农田景观步甲群落结构的时空动态比较

2000年5～10月在北京海淀区东北旺实验基地,采用陷阱法对林地、农田边界和农田3类生境共14个处理的步甲进行了取样。并在此基础上分析了不同生境和不同季节步甲科昆虫群落的动态分布特征。结果表明,林地和农田边界类生境相对于农田类生境拥有更多的步甲个体数和物种数;无论是优势种还是稀有种都趋向于在林地和边界处生活;边界对相邻农田步甲群落的多样性有积极影响;对边界进行适度的干扰(秋季翻耕)有利于提高步甲群落的个体数量;农田生境中灌溉、施肥和秸秆还田对农田中步甲群落的个体数量和物种数量的空间分布均无显著影响。此外,还结合步甲的时空分布特性对步甲受威胁状况进行了初步的分析。     

The role of various meadow margin types in shaping carabid and staphylinid beetle assemblages (Coleoptera: Carabidae,Staphylinidae) in meadow dominated landscapes

Less intensively managed semi-natural habitats, e.g., field and meadow margins like hedgerows, are thought to be crucial landscape components for maintaining biodiversity in highly disturbed and intensively managed agricultural landscapes. In this study, we focused on the effects of three meadow margin types on activity-density, species richness and species composition of carabid and staphylinid beetles recorded by pitfall traps in Central European landscapes dominated by intensively managed meadows. Carabid activity-density was significantly higher in meadows than in meadow margins and within meadow margins their activity-density increased from grassy meadow margins via shrubby ones to woody meadow margins. We found that recorded species richness of both carabid and staphylinid beetles was not significantly affected by habitat identity (meadow margin or neighbouring meadow) and meadow margin type. Recorded species composition of both investigated taxa was significantly affected by habitat identity and interaction between habitat identity and meadow margin type (i.e. it differed between particular meadow margin types). Assemblages inhabiting various meadow margin types were more dissimilar between each other than assemblages from neighbouring meadows. Meadow margins within grassland dominated landscapes maintain local species richness by hosting different species from those living in surrounding meadows. Dissimilarity of carabid and staphylinid assemblages from meadows neighbouring both sides of particular meadow margin did not differ between meadow margin types. Our results indicate that semi-natural habitats play an important role in maintaining biodiversity not only in agricultural landscapes dominated by arable fields, but also in those dominated by meadows.     

Heterogeneity from increasing crop types: effect on carabid beetles

We investigated the effect of crop type heterogeneity on carabid beetles in intensively managed agricultural landscapes. We compared different crops and habitat type configurations and compositions. In addition we assessed the effect of artificial fragmentation by paved roads and water channels in an agricultural landscape. Crop type heterogeneity negatively affected carabid assemblages. Spatial dissection by artificial structures had an even more negative effect on carabid diversity. The nested structure of the carabid assemblages among crop types was caused by a negative response to heterogeneity in the agricultural landscape. Even though crop types in an intensive agricultural landscape increased, the landscape may tend to fragment habitat. Although artificially fragmented habitats had more unstable carabid assemblages, heterogeneity from different crop types has also been shown to be a characteristic of fragmented landscapes. To produce a positive relationship between biodiversity and heterogeneity in an agricultural landscape, farming intensity should be reduced to allow for the conversion of highly productive lands into more natural habitats.     

Changes in carabid beetle diversity within a fragmented agricultural landscape

The distribution of carabid and cicindelid (Coleoptera: Carabidae) beetles in five distinct habitats (riparian, mature orchard, pine windbreak, young orchard, natural veld), within Tambuti Citrus Estate (Swaziland) was examined by pitfall trapping over 18 months. Habitats with high vegetation and litter cover had the highest species diversity and larger specimens, e.g. riparian border and pine windbreak, while the lowest diversity was observed in intensively managed mature citrus orchards. While species such as Tefflus delagorguei Guérin occurred in all the habitats sampled, certain species illustrated habitat specificity; e.g. Dromica ambitiosa Péringuey was observed only in the pine windbreaks while Haplotrachelus sp. Chaudoir occurred mainly in the vegetated riparian and natural veld habitats. Four unidentified carabid beetles were exclusive to the riparian border habitat. This habitat was the only one with a distinct assemblage of species in the agricultural mosaic studied. Multivariate analyses were used to assess the role of soil and environmental variables in relation to the ground beetle diversity within the agricultural mosaic studied.     

Ground beetle (Coleoptera: Carabidae) assemblages associated with a satoyama landscape in Japan: the effects of soil moisture,weed height,and distance from woodlands

Agricultural landscapes generally include not only crop fields but also semi-natural habitats. In Japan, such a mixed rural landscape is called “satoyama.” Although ground beetles are potential predators of pests, the environmental factors that determine their distribution in Japanese rural landscapes have not been fully elucidated. To understand the effects of distance from woodland edges, soil moisture, and weed height on assemblages of carabid beetles, we examined the number of adult beetles in pitfall traps placed in a satoyama landscape in the lowlands of western Honshu, Japan. Our results show that the carabid species could be largely differentiated into woodland, intermediate, and open-land species. The “intermediate species” group includes species that depend on woodland or woodland edges for at least part of their life cycles. Paddy fields must have long provided semi-natural habitats that complement those in natural grasslands and wetlands for open-land beetles that prefer wet conditions. Weeds can also increase the abundance of some intermediate and woodland species; thus, the arrangement of such landscape elements as woodlands and paddies can determine the species richness and abundance of ground beetles in agricultural fields.     

Landscape level processes driving carabid crop assemblage in dynamic farmlands

Landscape heterogeneity has been shown to be a major factor in the maintenance of biodiversity and associated services in agricultural landscapes. Farmlands are mosaics of fields with various crop types and farming practices. Crop phenology creates asynchrony between fields sown and harvested in different periods (winter vs. spring crops). The present study was conducted to examine the influence of such spatio-temporal heterogeneity on biodiversity, with the hypothesis that it would lead to spatio-temporal redistribution (shifting) of species. Species richness and activity-density of carabid beetles in winter cereal (winter) and maize (spring) crops were compared across 20 landscapes distributed along a double gradient of relative area and spatial configuration of winter and spring crops. Maize fields were sampled in spring and late summer for comparison over time. The response of carabid species richness to landscape heterogeneity was weak in spring, but maize field richness benefited from adjacencies with woody habitat, in late summer. In spring, increased length of interfaces between winter and spring crops lowered carabid activity-density in winter cereal fields, suggesting that maize fields acted as sinks. Interfaces between woody habitats and crops increased activity-density in both crop types. We found no evidence of spatio-temporal complementation, but different species benefited from winter cereals and maize in spring and late summer, increasing overall diversity. These findings confirm the role of adjacencies between woody and cultivated habitats in the conservation of abundant carabid assemblage in winter cereals and maize. We conclude that between-field population movement occurs, and advocate for better consideration of farmland heterogeneity in future research.     

Genetic diversity of the subterranean Gansu zokor in a semi-natural landscape

We studied the relationship between genetic diversity of the subterranean Gansu zokor Myospalax cansus and habitat variability in the Loess Plateau, Qinghai Province, China. We used a combination of geographic information systems and molecular techniques to assess the impact of habitat composition and human activities on the genetic diversity of zokor populations in this semi-natural landscape. Although they occurred relatively infrequently in the landscape, woodland and high-coverage grassland habitats were the main positive contributors to the genetic diversity of zokor populations. Rural residential land, plain agricultural land and low-coverage grassland had a negative effect on genetic diversity. Hilly agricultural land and middle-coverage grassland had little impact on zokor genetic diversity. There were also interactions between some habitat types, that is, habitat types with relatively better quality together promoted conservation of genetic diversity, while the interaction between (among) bad habitat types made situations worse. Finally, habitat diversity, measured as patch richness and Shannon's diversity index, was positively correlated with the genetic diversity. These results demonstrated that: (1) different habitat types had different effects on the genetic diversity of zokor populations and (2) habitat quality and habitat heterogeneity were important in maintaining genetic diversity. Habitat composition was closely related to land use thus emphasizing the importance of human activities on the genetic diversity of subterranean rodent populations in this semi-natural landscape. Although the Gansu zokor was considered to be a pest species in the Loess Plateau, our study provides insights for the management and conservation of other subterranean rodent species.     

Effects of landscape connectivity on the spatial distribution of insect diversity in agricultural mosaic landscapes

European agricultural landscapes are mosaics of intensively cultivated areas and semi-natural elements. Although comprising only a small fraction of the total area, semi-natural elements provide habitat for most of the landscape biodiversity. Agricultural intensification has increasingly fragmented semi-natural elements and species numbers are in decline. Insights into the effects of landscape structure on species’ distributions within and among semi-natural habitats are needed to conserve biodiversity in agricultural landscapes more effectively. We investigated the landscape- and habitat-specific diversity partitions of wild bees, true bugs, and carabid beetles in two differently structured agricultural landscapes in Switzerland. In each landscape, we partitioned the total species diversity (γ) into its additive components within (_P) and among patches (β_P) and among habitats (β_H). In the landscape characterized by a patchy, isolated distribution of habitat elements, among-patch diversity (β_P) explained 44% of the total species richness (γ) and was significantly higher than expected under a random distribution of samples among habitat patches; in the landscape with higher habitat connectivity, among-patch diversity (β_P) comprised 32% of the total species richness (γ) and did not differ from the random expectation. Habitat-specific within-patch contributions to species richness were similarly low across habitat types (_P=23–24%) in the patchy landscape, whereas in the more connected landscape within-patch partitions tended to be higher and differed among habitat types (_P=22–38%). Functionally different groups of bees, true bugs, and carabids also responded differently to landscape structure in a manner that was consistent with known differences in resource specialization and dispersal ability. Differences in diversity partitions among landscapes and taxa indicate the need for flexible conservation strategies. Conservation of habitat-specific diversity may require more habitat patches in landscapes that have lower habitat connectivity and low within-patch diversity (_P) than in landscapes with higher within-patch diversity (_P).     

黄河下游农业景观中不同生境类型地表节肢动物优势类群

生物多样性是连接景观异质性与生态系统服务的桥梁。在区域尺度上,以指示类群代替地表节肢动物类群,可以有效的开展生物多样性的保护工作。但是,在黄河下游农业景观中,关于地表节肢动物指示类群的研究报道较少。以黄河下游农业景观中4种生境类型(农田、林地、树篱和沟渠)为研究样地,且在农田生境中划分不同尺度(尺度1,3.6 hm2、尺度2,14 hm2和尺度3,28 hm2),通过调查不同生境中地表节肢动物分布及其多样性,结合地表节肢动物优势类群的辨识,分析了优势类群和地表节肢动物多样性的相关性,确定了研究区内地表节肢动物多样性的指示类群。结果发现:研究区内地表节肢动物优势类群为膜翅目、鞘翅目和蜘蛛目。树篱和林地生境的地表节肢动物多样性指示类群是膜翅目,农田生境中地表节肢动物多样性指示类群是鞘翅目,沟渠生境中地表节肢动物多样性指示类群是蜘蛛目。农田生境中优势类群间无相关性(P0.05);林地、沟渠和树篱生境中鞘翅目与蜘蛛目之间存在显著正相关(P0.01);林地和沟渠生境中,鞘翅目与膜翅目之间存在正相关(P0.05)。在农田生境中优势类群之间的相关性存在尺度依赖性,随着空间尺度的增大,相关性有一定的增强。在尺度2和尺度3上膜翅目和鞘翅目均存在正相关(P0.05),并且随着尺度增加而呈上升趋势。研究表明,黄河下游农业景观中不同生境类型地表节肢动物多样性的指示类群差别较大,其中树篱和林地生境具有较高的相似性,而农田生境地表节肢动物优势类群相关性存在尺度依赖性。在黄河下游农业景观中,以优势类群多样性代替地表节肢动物类群的多样性,可以在条件不足、时间紧迫的情况下更加有效的开展生物多样性的保护工作。