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1.
沧州市郊区蝗虫的初步调查   总被引:3,自引:0,他引:3  
孟德荣  金世雄 《昆虫知识》2002,39(2):120-122
作者于 1 998~ 2 0 0 0年对沧州市郊区的蝗虫资源进行了调查 ,结果显示蝗亚目昆虫 1 9种 ,分隶于 2总科 7科 1 7属 ,分布于芦苇湿地、碱荒地和农耕旱地 3种生态环境。明确了各种生态环境的优势种、常见种和稀少种类 ,其区系为古北界与东洋界过渡地带 ,以古北界为主  相似文献   

2.
田方文  李金枝 《昆虫知识》2010,47(5):1006-1010
通过1989—2008年的系统普查与探讨,查明滨州市蝗虫种类总科共18种,隶属于6科15属;分布于农田、夹荒、荒洼、特殊环境4个生态环境;明确了各生态环境、各个时期的优势种,常见种和少见种,及各蝗种的区系性质;明确了7种优势蝗种和2种少见种的生活史及习性。  相似文献   

3.
长薄鳅人工繁殖技术的研究   总被引:9,自引:1,他引:8  
长薄鳅Leptobotiaelongata (Bleeker)隶属鳅科、薄鳅属 ,分布于长江中上游江段及其支流 ,是鳅科鱼类中生长最快、个体最大的一种。 2 0世纪 70年代 ,常见个体 0 2 0— 0 40kg,最大个体达 3 0kg。其体两侧及鳍条上具鲜艳夺目的花斑 ,具有极高的观赏价值 ,在国内、国际市场上享有盛誉 ,是一种既可观赏又可作食用鱼养殖的名优经济鱼。然而 ,近 2 0多年来 ,人为过度捕捞、生态环境破坏等原因 ,在长江中游已很难捕到此鱼 ,长江上游的资源也在急速下降。近 1 0年来 ,鉴于长薄鳅急剧下降的资源和良好的开发利用前景…  相似文献   

4.
菏泽市蝗虫调查初报   总被引:2,自引:0,他引:2  
近年对山东省菏泽市的蝗虫资源进行了调查,结果显示蝗亚目昆虫23种,分隶于2总科7科20属,分布于黄河滩地、库洼地、缓平坡地、低山残丘四种生态环境。明确了各种生态环境的优势种、常见种和稀少种,其区系为古北与东洋界过渡地带,古北种、东洋种均占相当比例,广布种具明显优势。  相似文献   

5.
以蛛治虫对优化稻田生态系统的作用   总被引:6,自引:0,他引:6  
我国稻田蜘蛛已知有 2 3科 1 0 9属 373种 ,其中东南、西南、华中、西北和东北稻区分别为 2 2 8、2 2 0、2 0 7、1 2 6和 97种 .田间优势种群较其它天敌相对稳定 ,蜘蛛与稻飞虱的种群数量季节消长和生态分布相关性强 ,彼此制约关系明显 .以蛛治虫 ,创造有利于蜘蛛发生发展的生态环境 ,大幅度减少了化学农药的用量 ,保护了其它天敌 ,发挥多种天敌对稻虫的自然控制力 ,减少了环境污染 ,优化了稻田生态系统 ,使之呈良性循环  相似文献   

6.
长薄鳅仔稚鱼发育和生长的研究   总被引:10,自引:0,他引:10  
长薄鳅Leptobotiaelongata(Bleeker)隶属鳅科、薄鳅属 ,分布在长江中上游江段及其支流 ,是鳅科鱼类中生长最快、个体最大的一种 ,最大个体达 3 .0kg[1]。然而近 2 0多年来 ,人为过度捕捞、生态环境破坏等原因 ,在长江中游已很难捕到此鱼 ,长江上游也正面临着生存环境的破坏而资  相似文献   

7.
山东嘉祥县土蝗种类组成、分布和区域防治   总被引:1,自引:0,他引:1  
连续 2年普查结果表明 ,嘉祥县共有土蝗 1 7种 ,分属 2总科 6科 1 5属 ,同时还摸清了土蝗的优势种类、分布区域范围及发生规律。不同生态环境条件下其优势种分布有明显不同 ,地形地貌及植被覆盖度对土蝗发生有明显的影响  相似文献   

8.
山西蟒河自然保护区种子植物区系研究   总被引:12,自引:1,他引:11  
蟒河自然保护区位于山西省中条山脉东端的阳城县境内 ,1 1 2°2 2′1 1″~ 1 1 2° 31′35″E ,35°1 2′30″~ 35°1 7′2 0″N ,面积 5 5 73hm2 。蟒河自然保护区有种子植物 866种 ,隶属于 435属 1 0 3科 ,其中裸子植物 3科 5属 6种 ,被子植物 1 0 0科 430属 860种 (双子叶植物 90科 364属748种 ;单子叶植物 1 0科 66属 1 1 2种 )。蟒河自然保护区种子植物科属种的区系地理成分复杂多样。科的分布区类型以热带亚热带温带分布占优势 (共 45科 ,占总科数的 43.69% ) ,其次是温带分布 (共 2 9科 ,占 2 8.1 6% )。属的分布区类型以温带成分占优势 (共 2 64属 ,占总属数的 60 .69% ) ,其中北温带分布型优势明显 ( 1 36属 ,占总属数的 31 .2 6% ) ,反映出该区系明显的暖温带性质。种的分布区类型中国特有分布占有绝对优势 ( 30 5种 ,占总种数的 35 .2 2 % ) ,作为群落建群种或优势种的有油松、白皮松、青杨、红桦、橿子栎、青檀、锐齿槲栎、虎榛子、陕西荚蒾等 ,其次是温带亚洲分布 ( 1 90种 ,35 .2 2 % )、东亚分布 ( 1 5 4种 ,1 7.78% )。保护区内有国家级保护的珍惜濒危野生植物 8种 ,如南方红豆杉、连香树、无喙兰和天麻等。  相似文献   

9.
初步调查统计秦岭南坡中段有种子植物 1 55科 ,81 5属 ,约 2 1 84种 ,分别占秦岭总科数的 96.2 7% ,总属数的 80 .69% ,总种数的 63.32 %。其中有国家保护植物 31种 ,中国种子植物特有属 34属。属的地理分布类型多 ,有 1 5个分布型及 2 1个变型 ,其中温带成分和热带成分分别占该区总属数的 30 .66%和 64.79%。科的组成中含 1 0 0种以上的有 3科 ,50~ 1 0 0种的有 7科 ,5~ 2种的有 4 4科 ,含 1种的有 34科。秦岭南坡中段是生物多样性丰富的区域之一。论述了种子植物物种多样性 ,生活型多样性和属的分布区类型的多样性等。同时对该段生物多样性的保护与持续发展对策进行了探讨。  相似文献   

10.
浙江磐安种子植物区系的特征分析   总被引:5,自引:0,他引:5  
郝朝运  刘鹏  吕思田 《广西植物》2004,24(6):497-502
磐安约有野生种子植物 1 44科 ,62 7属 ,1 2 98种 (包括种以下分类单位 )。其中世界成分的属 67个 ,占总属数的 1 0 .69% ,热带属 2 2 7个 ,占 36.2 0 % ,温带属 32 1个 ,占 5 1 .2 0 % ,中国特有属 1 2个 ,占 1 .91 %。磐安气候温暖湿润 ,植物种类丰富 ,古老、孑遗、珍稀植物多 ,单种属和少种属占有较大比重 ;优势科、优势属明显 ,优势科 34个 ,共含有 393属 ,776种 ,分别占总属数总种属的 62 .7% ,70 .3% ,优势属 1 0个 ,共含有 1 44种 ,分别占总属数总种数的 1 .6% ,1 1 .1 % ,其中樟科、壳斗科等是该区系的表征科 ;植物分布类型多样 ,地理成分复杂 ,温带成分和热带成分占优势 ,是亚热带分布的北缘 ,与世界各地有广泛的联系  相似文献   

11.
The introduction of non-native species represents unprecedented large-scale experiments that allow us to examine ecological systems in ways that would otherwise not be possible. Invasion by novel ecological types into a community can press a system beyond the bounds normally seen and can reveal community interactions, local drivers and limits within systems that are otherwise hidden by coevolution and a long evolutionary history among local players, as well as local adaptation of species. The success of many invaders is attributed to their ability to thrive in a wide range of habitat types and physical conditions, setting the stage for direct examination of ecological impacts of a species across a range of habitat and community contexts. Bivalves are well-known ecosystem engineers, especially oysters, which are the target of wild-caught fisheries and aquaculture. The Pacific oyster, Crassostrea gigas, is grown worldwide for aquaculture, and is presently invading shores on virtually every continent. As a consequence, this non-native species is having large impacts on many systems, but the types of impacts are system specific, and greatly depend on substrate type, how physiologically stressful the environment is for intertidal zone species, and the presence of native engineering species. A novel type of engineering effect is identified for this non-native species, whereby it alters not only the physical environment, but also the thermal environment of the community it invades. The impacts of engineering by this non-native species will depend not only on whether it facilitates or inhibits species but also on the trophic level and ecological role of the species affected, and whether similar ecological types are found within the system.  相似文献   

12.
为了减少或避免在农林业生产中因土壤、气候不适宜造成的冻害或其它自然灾害造成的不必要的损失,最大限度地利用洞庭湖水系(湖南地区)区域内的气候资源、水热资源以及土壤资源,本文依据洞庭湖水系(湖南地区)区域内89个样本县(市)气象台(站)30年的气候资料及其地貌、土壤等生态环境特性值,采用主分量(PCA)分析的方法,并结合定性分桥,对洞庭湖水系(湖南地区)进行了生态类型区划分的研究,其结果将该区域划分成5个生态类型区,并结合26个主要经济树种草种分布的气候、水热条件、地貌和土壤等生态环境的差异性,对26个树种草种进行了最适宜、适宜、较适宜栽培的生态类型区的选择研究,相应地对各生态类型区进行了主栽树种和辅栽树种的分析。  相似文献   

13.
王贺新  杨秀清 《植物研究》1994,14(3):292-298
本文通过物种多样性指数、生态优势度、群落均匀度、重要值等指标综合分析了野生人参自然分布的典型椴树阔叶红松林的群落特征.结果认为椴树阔叶红松林内物种数及其个体数量较多,多样性指数及群落的均匀度都较高,物种分布均匀并具有明显的层次,生态优势度较低,具有较稳定的群落结构.这种群落特征给人参的生活和生长创造了适宜的生态条件,是人参这一古老遗植物在这种群落中得以长期保存和生长繁衍的主要因素.  相似文献   

14.
Katherine Mertes  Walter Jetz 《Ecography》2018,41(10):1604-1615
Understanding species’ responses to environmental conditions, and how these ­species–environment associations shape spatial distributions, are longstanding goals in ecology and biogeography. However, an essential component of species–environment relationships – the spatial unit, or grain, at which they operate – remains unresolved. We identify three components of scale‐dependence in analyses of species–environment associations: 1) response grain, the grain at which species respond most strongly to their environment; 2) environment spatial structure, the pattern of spatial autocorrelation intrinsic to an environmental factor; and 3) analysis grain, the grain at which analyses are conducted and ecological inferences are made. We introduce a novel conceptual framework that defines these scale components in the context of analyzing species–environment relationships, and provide theoretical examples of their interactions for species with various ecological attributes. We then use a virtual species approach to investigate the impacts of each component on common methods of measuring and predicting species–environment relationships. We find that environment spatial structure has a substantial impact on the ability of even simple, univariate species distribution models (SDMs) to recover known species–­environment associations at coarse analysis grains. For simulated environments with ‘fine’ and ‘intermediate’ spatial structure, model explanatory power, and the frequency with which simple SDMs correctly estimated a virtual species’ response to the simulated environment, dramatically declined as analysis grain increased. Informed by these results, we use a scaling analysis to identify maximum analysis grains for individual environmental factors, and a scale optimization procedure to determine the grain of maximum predictive accuracy. Implementing these analysis grain thresholds and model performance standards in an example east African study system yields more accurate distribution predictions, compared to SDMs independently constructed at arbitrary analysis grains. Finally, we integrate our conceptual framework with virtual and empirical results to provide practical recommendations for researchers asking common questions about species–environment relationships.  相似文献   

15.
We will elaborate the evolutionary course of an ecosystem consisting of a population in a chemostat environment with periodically fluctuating nutrient supply. The organisms that make up the population consist of structural biomass and energy storage compartments. In a constant chemostat environment a species without energy storage always out-competes a species with energy reserves. This hinders evolution of species with storage from those without storage. Using the adaptive dynamics approach for non-equilibrium ecological systems we will show that in a fluctuating environment there are multiple stable evolutionary singular strategies (ss's): one for a species without, and one for a species with energy storage. The evolutionary end-point depends on the initial evolutionary state. We will formulate the invasion fitness in terms of Floquet multipliers for the oscillating non-autonomous system. Bifurcation theory is used to study points where due to evolutionary development by mutational steps, the long-term dynamics of the ecological system changes qualitatively. To that end, at the ecological time scale, the trait value at which invasion of a mutant into a resident population becomes possible can be calculated using numerical bifurcation analysis where the trait is used as the free parameter, because it is just a bifurcation point. In a constant environment there is a unique stable equilibrium for one species following the “competitive exclusion” principle. In contrast, due to the oscillatory dynamics on the ecological time scale two species may coexist. That is, non-equilibrium dynamics enhances biodiversity. However, we will show that this coexistence is not stable on the evolutionary time scale and always one single species survives.  相似文献   

16.
莽山自然保护区陆生贝类的种类组成及区系分析   总被引:3,自引:0,他引:3  
首次报道了莽山自然保护区陆生贝类39种,隶属于2亚纲、10科、19属;介绍了莽山的自然概况;对莽山自然保护区陆生贝类的种类组成、区系特点、生态分布与栖息环境之间的关系进行了分析。  相似文献   

17.
鱼类是水域生态系统的重要组成部分, 也是水域生态环境良好的指示类群。为合理评估长江生态环境的现状和变化趋势, 文章提出将土著鱼类物种数和珍稀特有鱼类物种数作为评价指标, 并建立了相关的评价基准和等级划分标准。以2010年和2020年为评价年, 评估了长江干流及代表性重点水域的生态环境质量。结果显示, 当前长江上游干流和下游干流的生态环境质量优于中游; 支流赤水河的生态环境质量良好, 大型湖泊鄱阳湖的生态环境质量中等。从时间上看, 随着长江十年禁渔等一系列保护措施的实施, 长江干流的生态环境质量有不同程度地好转。在此基础上, 提出了进一步改善长江生态环境的对策与建议。  相似文献   

18.

Background  

The growth-rate of an organism is an important phenotypic trait, directly affecting its ability to survive in a given environment. Here we present the first large scale computational study of the association between ecological strategies and growth rate across 113 bacterial species, occupying a variety of metabolic habitats. Genomic data are used to reconstruct the species' metabolic networks and habitable metabolic environments. These reconstructions are then used to investigate the typical ecological strategies taken by organisms in terms of two basic species-specific measures: metabolic variability - the ability of a species to survive in a variety of different environments; and co-habitation score vector - the distribution of other species that co-inhabit each environment.  相似文献   

19.
In ecology, multi-scale analyses are commonly performed to identify the scale at which a species interacts with its environment (intrinsic scale). This is typically carried out using multi-scale species–environment models that compare the relationship between ecological attributes (e.g., species diversity) measured with point data to environmental data (e.g. vegetation cover) for the surrounding area within buffers of multiple sizes. The intrinsic scale is identified as the buffer size at which the highest correlation between environmental and ecological variables occurs. We present the first investigation of how the spatial resolution of remote sensing environmental data can influence the identification of the intrinsic scale using multi-scale species–environment models. Using the virtual ecologist approach we tested this influence using vegetation cover spatial data and a simulated species–environment relationship derived from the same spatial data. By using a simulation model there was a known truth to use as a benchmark to measure accuracy. Our findings indicate that by varying the spatial resolution of the environmental data, the intrinsic scale may be incorrectly identified. In some cases, the errors in the intrinsic scale identified were close to the maximum value possible that could be measured by this experiment. Consequently, multi-scale ecological analyses may not be suitable for distinguishing scale patterns caused by the relationship between an organism and its environment from scale patterns caused by the effect of changing spatial resolution: a phenomenon referred to as the modifiable areal unit problem (MAUP). Thus, observed scale-dependent ecological patterns may be an artefact of the observation of ecological data, not the ecological phenomenon. This study concludes with some suggestions for future work to quantify the effect of the MAUP on multi-scale studies and develop generalisations that can be used to assess when multi-scale analyses have the potential to produce spurious results.  相似文献   

20.
宋础良 《生物多样性》2020,28(11):1345-57
群落内物种间相互作用的结构是高度组织化的。群落结构对多物种共存的影响机制是群落生态学的核心科学问题之一。目前生态学界在这一问题上存在多种不同的观点。一个可能的原因是, 由于环境因子的复杂性, 大部分研究忽略了环境因子对群落结构和物种共存的重要影响。在这一背景下, 近期发展起来的结构稳定性理论系统地联系了群落结构、环境因子和物种共存, 并在此基础上建立了一个和经验数据紧密结合的理论框架。本文首先简要回顾了当前关于群落结构研究的争鸣, 然后介绍了结构稳定性的理论框架和计算方法, 最后详细介绍了结构稳定性理论在不同生态群落和不同生态学问题中的应用。在全球气候变化的背景下, 结构稳定性理论提供了一种新的视角来理解群落层面的生物多样性维持机制。  相似文献   

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