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1.
准噶尔盆地柽柳科植物生物多样性及保护对策 总被引：2，自引：1，他引：1
从遗传、物种、群落、生态系统四个层次讨论了新疆准噶尔盆地柽柳科植物生物多样性特征、组成、结构、空间分布规律 ,分析了准噶尔盆地柽柳科植物多样性受破坏的自然因素和人为因素。以现代保护生物学理论为根据 ,提出新疆准噶尔盆地柽柳科植物生物多样性的保护战略和措施。 相似文献
2.
种子是保存物种遗传信息的载体,保护种子资源是植物保护和生物多样性保护的重要内容。种子传播不仅对保护植物自身的繁殖和生存至关重要,而且对群落稳定甚至生态系统功能具有重要意义。该文综述了种子传播的方式、干扰因素以及种子传播通过提高生物多样性来促进植物保护的机制,即丰富的生物多样性降低了病虫害对植物的危害。种子传播易受人为活动和气候变化等因素干扰传播媒介和破坏生境;需要采取构建廊道等措施来降低因生境破碎化引起的负面影响。种子传播提高生物多样性的机制主要通过增加基因交流来提高遗传多样性,通过增加种子扩散效率和存活率等来提高物种多样性、稳定群落结构和通过连通生境斑块来提高生态系统多样性。因此,构建基于生态系统的种子传播网络对保护生物多样性具有重要意义。 相似文献
3.
论三江源自然保护区生物多样性保护 总被引：8，自引：1，他引：7
经过我们的多次科考调查:三江源保护区地理位置和生态环境独特、地形地貌复杂,自然环境类型多样,是生物多样性最丰富、最集中的地区,动植物中有许多保护种和特有种;同时,三江源保护区也是生态系统最敏感的地区,近几十年来,由于自然和人类活动的双重作用,生态环境逐渐退化,生物多样性种类和数量锐减,生物多样性保护刻不容缓。只有加强科学管理和生态建设,恢复和重建三江源保护区生态系统和栖息地环境,才能使三江源区生物多样性得到有效保护。 相似文献
4.
大青山山地植物区系及生物多样性研究 总被引：3，自引：0，他引：3
生物多样性空间分布格局及其成因一直是生态学和保护生物学研究的热点。文中以大青山山地为研究对象,基于植物群落调查,通过物种和功能群层次多样性指数的计算,及其与环境因子的相关性、典范对应分析,旨在揭示山地生物多样性的空间分布格局及其成因。研究结果表明:(1)大青山具有丰富的植被类型,植被型包括森林、灌丛和草原三种;(2)大青山植被物种多样性分布格局具有垂直特征;(3)坡向是导致植物群落物种多样性差异的主要影响因子;(4)水热因子共同作用的环境条件是决定山地植被生物多样性分布格局的主要原因。 相似文献
5.
在天山西部根据生境特点设置90个1m×1m草本样方,研究了天山云杉林草本植物的物种多样性季节动态。结果表明:共调查到162种草本植物,隶属于34科、110属。草本植物多样性季节变化明显,生长季内物种数、Gleason丰富度指数、Simpson和Shannon-Wiener多样性指数均呈单峰型分布,即6、7月最高,4、9月最低。不同生境草本植物多样性变化明显,阴坡和林缘生境草本植物多样性最高,林冠干扰明显的生境中物种多样性最低。因此,草本植物多样性季节变化受微生境和人为干扰影响。 相似文献
6.
乌兰布和沙漠东北部几种白刺群落植物多样性研究 总被引：2，自引：0，他引：2
根据对乌兰布和沙漠东北部4种白刺植物群落的样地调查数据,采用物种丰富度指数S、Shannon-Wiener指数H'、Simpson指数D、Pielou均匀度指数J、Alatalo均匀度指数Ea、Whittaker指数βw、相异性系数CD、群落共有度Jaccard指数CP、Bray-Curtis指数CN等指标研究了该地区4种白刺群落分层的α多样性和β多样性。结果表明:这些α多样性和β多样性测度指标有效表征了干旱沙漠区同属不同植物群落内部在物种组成方面的差异、生境差异、群落间物种组成差异。四种白刺群落的草本层的物种丰富度指数都明显大于灌木层;唐古特白刺群落的物种丰富度指数最小,泡泡刺群落的物种多样性Shannon-Wiener指数H'和Simpson指数D最大,而且其群落均匀度也最大。唐古特白刺植物群落的Whittaker指数βw要比其它三种白刺群落要大,若仅考虑群落间共有物种数目多少,大白刺与泡泡刺在群落、灌木层与草本层间的相异性系数CD都最小,共有度Jaccard指数CP都最大;而西伯利亚白刺群落、灌木层和草本层与其余三种白刺的相异性系数CD都较大,Jaccard指数CP都较小。而数量数据指标Bray-Curtis指数CN变化与上述有所不同。采用植物盖度和相对盖度进行α多样性和β多样性对比分析,能够合理地说明不同白刺植物多样性特征。 相似文献
7.
天山北坡中段草地类型α多样性研究 总被引：4，自引：2，他引：2
定量比较天山北坡中段乌鲁木齐地区各草地植被垂直带中具代表性的16个主要草地类型的植物多样性指数、物种丰富度指数和均匀度指数。从各草地类型多样性指数大小来看,山地草甸>草甸草原>典型草原>荒漠草原>亚高山草甸>高寒草甸>荒漠。其中分布于山地草甸的鸭茅+草原老鹳草+杂类草的草地类型和草原老鹳草+杂类草+禾草的草地类型的物种多样性指数最大,而分布于荒漠带土质生境的散枝猪毛菜+角果藜的草地类型和小蓬草地类型的物种多样性指数最小。其结果反映了生境异质性沿着水、热生态梯度变化的规律;从草地物种多样性的角度,揭示了不同草地类型在组成、结构、功能和动态的差异;通过指数间相关关系的分析,探讨草地类型多样性与草地生产力的相互影响,可为该地区的生物多样性资源保护提供科学依据。 相似文献
8.
海拔是影响地衣物种分布的主要因素之一。文中以地衣的盖度为指标计算天山一号冰川6个不同海拔梯度岩面生地衣的多样性和相似性指数,同时分析了生长型与海拔间的关系。采用主成分分析和相关分析探讨了海拔对岩面生地衣多样性的确定影响。结果显示：分布在天山一号冰川的岩面生地衣共有89种,隶属于15科31属。岩面生地衣物种多样性先随着海拔梯度增加而增高,到了3700m高海拔后开始逐渐下降。地衣的生长型主要由壳状、鳞片状地衣为主的微小型地衣组成,叶状生长型3300m以上的地区均占一定比例;3600m以上的样点缺少枝状生长型,充分体现了岩面生地衣对高山极端环境的适应特征。研究结果阐明了天山一号冰川岩面生地衣的多样性及其分布特征,将可作为该地区进一步研究地衣物种多样性及长期环境监测的基础数据。 相似文献
9.
达尔文提出建立在物竞天择、适者生存、优胜劣汰等主题之上的自然选择理论之后,又提出了物种进化的第二种选择——性选择：雄性为获得交配权而互相竞争,竞争结果是失败者并不像自然选择中的那样是死亡,而是失败者因没有获得交配而不能产生后代。如今,性选择理论已历时150年,随着无数科学家的努力及大量研究的开展,性选择理论已经得到了巨大地拓展和丰富,成为进化生物学领域里最活跃的研究主题。由于昆虫的生物多样性,性选择研究在昆虫学中占据重要地位并取得了丰硕的成果,有些进一步丰富和拓展达尔文的性选择学说和物种进化理论。以昆虫特有形态结构、生理特征和行为习惯等性状的性选择为基础,以分析昆虫性选择的模式和机制为目标,从不同时期性选择的表现形式、不同影响因素造成的性选择等,对昆虫性选择加以综合阐述。 相似文献
10.
在对江西南昌市梅岭景区6个典型景点中的蜘蛛多样性进行调查、鉴定并获得其蜘蛛资源详实分布名录的基础上,结合另文对其多样性的比较研究结果,通过将其39个未确定种的各科属级物种丰富度、景点物种多样性、群落结构多样性和捕食功能多样性共13个指数作为变量对其区域特色种作用因子进行主成分、相关性和聚类等统计分析,揭示其多样性形成原因和方式。结果表明:景点物种均匀度、景点物种丰富度、景点物种优势度、捕食功能均匀度、群落结构丰富度、捕食功能丰富度是区域特色种形成的6个主要作用因子,各因子间普遍相关,且生态和遗传因素各有侧重地作用于区域特色种的形成。 相似文献
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12.
新疆各类陆栖脊椎动物近 70 0种 ,占中国这一类动物种数的 32 %,其中鸟兽资源尤其丰富 ,计有 42 5种鸟类和 1 5 5种兽类 (哺乳类 ) ,占中国鸟兽种数的 31 %。本文主要以新疆三大山区———阿尔泰山、天山、昆仑 -阿尔金山地区鸟类和哺乳类动物的多样性及区系分布作综合性介绍和分析。根据实地考察和以往文献资料 ,新疆阿尔泰山区记录在 1 2 4种鸟类 ,其中古北界北方型鸟类 5 1种 (占 41 .1 %) ,中亚型鸟类 31种 (占 2 5 .0 %) ,广布种鸟类 2 7种 (占 2 1 .8%) ,其他类型1 5种 (占 1 2 .1 %) ,显出以北方型泰加林鸟类为主的鸟类区系特征 ;分布的 5 0种兽类 ,区系上以古北界北方泰加林为主 ,即北方型兽类占该山区种数的 5 2 %。天山山区记录的鸟类大约2 81种 ,北方型种类占绝对优势 ,即北方型 1 0 6种 (占 37.72 %) ,北方广布型 76种 (占 2 7.0 4 %) ,中亚型 39种 (占 1 3.88%) ,高地型 1 8种 (占 6.41 %) ,广布型 33种 (占 1 1 .74%) ,东北型 9种 (占 3.2 1 %)。兽类分布有 62种 ,北方型兽类区系占优势 ,有 30种 (占 48.40 %) ,广布型 1 2种 (占 1 9.40 %) ,中亚型 1 1种 (占 1 7.70 %) ,特有种 9种 (占 1 4.5 0 %)。昆仑—阿尔金山地区 96种鸟类中 ,中亚类型成份占 2 8.1 %,高地型成分占 2 6%,北方型成? 相似文献
13.
Species richness and abundance are two important species diversity variables that have attracted particular attention because of their significance in determining present and future species composition conditions.This paper aims to explain the qualitative and quantitative relationships between species diversity pattern and grain size(i.e.size of the sampling unit),and species diversity pattern and sampling area,and to analyze species diversity variability on active sand dunes in the Horqin Sandy Land,northeastern Inner Mongolia,China.A 50 m×50 m sampling plot was selected on the windward slope,where the dominant species was annual herb Agriophyllum squarrosum.Species composition and abundance at five grain sizes were recorded,and the species-area curves were produced for thirteen grain sizes.The range of values for species abundance tended to increase with increasing grain size in the study area,whereas,generally,species richness did not follow this rule because of poor species richness on the windward slope of active sand dunes.However,the homogeneity of species richness increased significantly.With the increase in sampling area,species abundance increased linearly,but richness increased logarithmically.Furthermore,variograms showed that species diversity on the windward slope of active sand dunes was weakly anisotropic and the distribution pattern was random,according to the Moran Coefficient.The results also showed that species richness was low,with a random distribution pattern.This conflicts with the results of previous studies that showed spatial aggregation in lower richness in a sampling area within a community and inferred that the physical processes play a more important role in species diversity than distribution pattern on active sand dunes.Further research into different diversity patterns and mechanisms between active sand dunes and interdune lowlands should be conducted to better understand biodiversity conservation in sand dune fields. 相似文献
14.
Mohamed Neji Mohamed Moncef Serbaji Olivier Hardy Mohamed Chaieb 《Arid Land Research and Management》2018,32(3):291-315
Knowledge about vegetation patterns along disturbance gradients is essential for conservation and management of coastal habitats in arid regions. This study focuses on the floristic diversity and the factors controlling the vegetation structure in the Gulf of Gabès (Tunisia). For this purpose, the floristic diversity of 120 relevés belonging to three coastal sites with different disturbance levels (40 relevés per site) was analyzed in relation with 10 environmental and anthropogenic factors. Therophytes constitute 54% of the 237 plants species belonging to 44 families identified in the present study. The species richness and floristic diversity indices exhibited a similar trend and peaked in the slightly disturbed site (H′?=?3.38; S?=?176). The similarity between sites was relatively low and reached its maximum between the little and the highly disturbed sites. Two-way indicator species analysis and detrended correspondence analysis applied on the floristic data resulted in groups mainly determined by disturbance level by explicitly segregating the three sites. Canonical correspondence analysis (CCA) indicated that the spatial pattern of species composition was mainly influenced by anthropogenic variables. Partial CCA revealed that the effect of anthropogenic variables on floristic composition was thrice higher than the effect of environmental variables (57.5% vs. 18.4%, respectively). Overall, this study provides a broad understanding of the floristic diversity and vascular plant richness in the Gulf of Gabès. The obtained results reflected a disturbance–diversity pattern and thus revealed the obvious importance of maintaining the intermediate disturbance for biodiversity conservation and monitoring. 相似文献
15.
敦煌阳关自然保护区地处我国西北内陆腹地,主要保护对象为湿地、候鸟和荒漠生态系统。2006年3月~2007年4月,对该保护区鸟类的种类、数量、分布和生境等进行了多次科学调查。综合文献记载,得知阳关自然保护区共有鸟类86种,隶属13目,30科,57属,其中留鸟13种,夏候鸟47种,冬候鸟5种,旅鸟21种,国家重点保护鸟类10种。鸟类区系以古北界成分为主,占繁殖鸟总数的70%,而东洋界种类仅2种。生境类型包括湿地、草原、灌丛和居民点等。近年来保护区内珍稀鸟类数量不断减少,主要影响因素是栖息地丧失,人类活动和气候变化等。 相似文献
16.
芦芽山旅游干扰下不同植被景观区物种多样性的比较 总被引：3，自引：0，他引：3
利用12个物种多样性指数,研究了芦芽山不同植被景观区物种多样性的差异。结果表明:1)随着旅游干扰程度的减少,物种的均匀度和综合多样性表现出不断增大的趋势。至于物种丰富度的变化则与其不同,旅游活动的适度干扰有利于物种丰富度的增加,旅游干扰较少或干扰严重均不利于其增加。2)物种丰富度与坡度呈显著正相关,均匀度与海拔和路宽呈显著正相关,与旅游影响系数呈显著负相关,综合多样性与景观重要值呈显著正相关,与旅游影响系数呈极显著负相关。3)在丰富度指数上,Patrick指数和Margalef指数相对较好,而Menhinick指数相对较差。在均匀度指数上,Pielou指数、Sheldon指数和Heip指数属于一组,Hill指数和修正的Hill指数属于另一组。在综合多样性指数上,Shannon-Wiener指数、Hill的多样性指数N1和N2都表现出一致的变化趋势,而Simpson指数由于计算方式和所反映的生态意义特殊,因而其变化趋势与其它指数不同。 相似文献
17.
In Hungary, plant protection and soil conservation are not only believed to be closely related, but are managed in a single, nationwide Service. GIS is used to assist the Service in organising this joint activity by:
- • establishing the infrastructure suitable for coordinating different kinds of data collection, GIS processing, transfer and publication of such data
- • improving the staff capacity by providing training and technical assistance in using GIS, capturing field data, navigating and using thematic maps
- • creating a simple and interactive interface for accessing geographic data produced from activities of controlling use of plant protection products, in plant health, in controlling weeds and in soil conservation
- • providing guidance for designing, monitoring and assessing the impact of particular programmes (e.g. implementing nitrate and sewage sludge directives, ragweed eradication, survey and monitoring for quarantine and other economically important pests)
- • establishing an Agro‐environmental Information and Monitoring System to support environmentally friendly farming.
18.
THOMAS Jacob 《干旱区科学》2017,9(1):109-121
Shada Mountains in Saudi Arabia, separated by Maleel Wadi into twin mountains(i.e., Shada Alalah and Shada Asfal), are rich in biodiversity. We investigated the diversity of endemics and endangered species of the mountains based on the data collected from 38 stands falling in 8 elevational zones ranging from 500 to 2215 m a.s.l. Results indicated that 495 plant species falling in 314 genera and 76 families occurred in the Shada Mountains, including 19 endemic species and 43 endangered species, and accounting for 22% of the total flora in Saudi Arabia. Canonical correlation analysis indicated that physiographic features, particularly altitude play an important role in the frequency and abundance of species. Endemics were not evenly distributed in the Shada Mountains and mostly restricted in the elevation zone of 1000–1500 or 1500 m a.s.l. When the altitude reached up to 2000 m a.s.l., the endemics decreased substantially due to the significantly low temperature. The endangered species existed three different distribution patterns:(i) most endangered species distributed in the altitudes of 1000–1800 m a.s.l.;(ii) endangered trees, lianas, and shrubs occupied the altitudes 1000–1300 m a.s.l.; and(iii) endangered subshrubs and herbs inhabited the altitudes 1500–2100 m a.s.l. The results demonstrated that the biodiversity of endangered species in the Shada Mountains is high and undisturbed by invasive species, and protective measures should be taken against human disturbances to the small-scale hotspot. 相似文献
19.
The status of regional biodiversity is determined by habitat quality.The effective assessment of habitat quality can help balance the relationship between economic development and biodiversity conservation.Therefore,this study used the InVEST model to conduct a dynamic evaluation of the spatial and temporal changes in habitat quality of the Tarim River Basin in southern Xinjiang Uygur Autonomous Region of China by calc ulating the degradation degree levels for habitat types that were caused by threat factors from 1990 to 2018(represented by four periods of 1990,2000,2010 and 2018).Specifically,we used spatial autocorrelation analysis and Getis-Ord Gi*analysis to divide the study area into three heterogeneous units in terms of habitat quality:cold spot areas,hot spot areas and random areas.Hemeroby index,population density,gross domestic product(GDP),altitude and distance from water source(DWS)were then chosen as the main disturbance factors.Linear correlation and spatial regression models were subsequently used to analyze the influences of disturbance factors on habitat quality.The results demonstrated that the overall level of habitat quality in the TRB was poor,showing a continuous degradation state.The intensity of the negative correlation between habitat quality and Hemeroby index was proven to be strongest in cold spot areas,hot spot areas and random areas.The spatial lag model(SLM)was better suited to spatial regression analysis due to the spatial dependence of habitat quality and disturbance factors in heterogeneous units.By analyzing the model,Hemeroby index was found to have the greatest impact on habitat quality in the studied four periods(1990,2000,2010 and2018).The research results have potential guiding significance for the formulation of reasonable management policies in the TRB as well as other river basins in arid areas. 相似文献
20.
N Colbach L Biju‐Duval A Gardarin S Granger S H M Guyot D Mézière N M Munier‐Jolain S Petit 《Weed Research》2014,54(6):541-555
Weeds are both harmful for crop production and important for biodiversity, while herbicides can pollute the environment. We thus need new cropping systems optimising all cultural techniques, reconciling agricultural production, herbicide reduction and biodiversity conservation. Here, we show how to (i) develop models quantifying the effects of cropping systems on weed dynamics, (ii) integrate interactions between weeds and other organisms, (iii) predict the impact on production and biodiversity and (iv) use the model for multicriteria evaluation and multiobjective design of cropping systems. Among the existing weed dynamics models, we chose the one closest to our requirements to illustrate these different steps, that is, FlorSys which predicts multispecific weed dynamics as a function of cultural techniques and pedoclimate. We have illustrated the development of interaction submodels with the example of a crop pathogen whose propagation is increased when infecting grass weeds. To evaluate the weed flora impact, predicted weed densities were translated into indicators of harmfulness (crop yield loss, technical harvest problems, harvest pollution, field infestation, crop disease increase) and biodiversity (weed species richness and equitability, trophic resources for birds, insects and pollinators). Simulations were run over several years and with different weather scenarios (i) to optimise cultural techniques to control harmful weeds, (ii) to analyse the impact of changing agricultural practices (e.g. simplified tillage and rotations, no‐till, temporary crops) on weed density, species and trait composition and (iii) to evaluate cropping systems for their ability to reconcile agricultural production and biodiversity, thus identifying levers for designing sustainable cropping systems. 相似文献