首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
何云川  杨贵军  王新谱 《昆虫学报》2018,61(12):1439-1452
【目的】调查和分析银川不同湿地陆生昆虫群落结构组成、功能多样性及其稳定性变化。【方法】2016年5-10月选取银川黄河湿地(HH)、鸣翠湖湿地(MCH)、芦花台湿地(LHT)、水洞沟湿地(SDG)4种湿地生境,采用棋盘式扫网和陷阱捕捉的方法进行昆虫采集。根据调查数据进行昆虫群落结构多样性分析、主成分分析和聚类分析。【结果】4种湿地生境共采集昆虫38 668头,隶属13目97科370种。双翅目、同翅目、膜翅目在4种生境中均为优势类群。植食性(Ph)昆虫功能团的科数和种数在4种生境昆虫群落中占比均最大。植食性-中性昆虫(Ph-Ne)间个体数在4种生境下均存在显著负相关(P<0.01);植食性-捕食性昆虫(Ph-Pr)间个体数在MCH生境下存在显著正相关(P<0.05);中性-捕食性昆虫(Ne-Pr)间个体数在MCH生境下存在显著负相关(P<0.01),在LHT生境下存在显著负相关(P<0.05);4种功能团结构的其他组合的个体数在4种生境下均不存在显著相关性。主成分分析结果表明,捕食性类群是4个类群中影响构成昆虫群落组成的主要成分。同种功能团在4种生境下的多样性分析结果表明,捕食性功能团(Pr)与寄生性功能团(Pa)在4种生境群落中的群落丰富度、均匀程度[辛普森指数(Simpson index)]差异性显著(P<0.05),而植食性功能团(Ph)与中性功能团(Ne)的群落丰富度、均匀程度的差异性不显著(P>0.05);中性功能团(Ne)在4种生境群落中个体出现的不确定程度[香农-维纳指数(Shannon-Wiener index)]差异性不显著(P>0.05),在4种生境的均匀度指数(Pielou evenness index)差异性显著(P<0.05),其余3个功能团在4种生境下的香农-维纳指数均差异性显著(P<0.05),在4种生境下的均匀度指数均差异性不显著(P>0.05)。4种生境昆虫群落特征指数的聚类分析分为2类,永久性湿地HH和MCH为第1类,季节性湿地LHT和SDG为第2类。Ss/SiSa/Sp两个稳定性指标均显示MCH昆虫群落稳定性最高,4种生境昆虫群落最稳定的时期是5和9月。【结论】双翅目和膜翅目昆虫在银川不同湿地生境中均为优势类群,可作为环境指示参考;昆虫群落稳定性最好的湿地类型为永久性湖泊湿地;不同生境昆虫群落多样性随季节时序变化,在银川最稳定的时期是5和9月。气候因子、环境因素如何驱动各湿地昆虫群落多样性及稳定性的变化因素还有待开展研究。  相似文献   

2.
To investigate whether similar physiognomic areas support similar faunas, the richness, similarity, and community structure of the ant fauna attracted to baits in an area of the Brazilian Cerrado sensu stricto at the core of the domain and in two Cerrado 'islands' (one of sensu stricto and another of 'cerradão') were compared. In each locality, four collecting events were performed (two during the day and two at night) capturing ants attracted to 400 sardine baits (200 in soil, 200 in vegetation). Ants of six subfamilies, 33 genera, and 121 species were identified visiting baits in the three areas (180 species estimated). The most speciose genera were Camponotus (27 species), Pheidole (13), Solenopsis (11), and Crematogaster (8). The similarity values between pair sites can be considered medium in relation to other studies. The highest value was recorded for the core area and the 'island' of Cerrado sensu stricto (Morisita-Horn = 0.57). The two Cerrado 'islands' were found to be 0.44 similar and the core area and the 'cerradão' 0.41 similar. The ordination analysis (non-metric multidimensional scaling) revealed discontinuities in species distributions between areas of Cerrado sensu stricto and 'cerradão,' and distinctive ant faunas relative to the temporal (nocturnal and diurnal) and foraging niches (ground and vegetation). The ant fauna at ground level in the 'cerradão' and Cerrado sensu stricto showed the greatest dissimilarity. The data suggest that areas of Cerrado are characterized by relatively high local ant fauna richness, and that community structure is influenced by the distance between sites and the diversity of vegetation.  相似文献   

3.
深圳湾福田红树林群落演替   总被引:3,自引:2,他引:3  
对深圳湾福田凤塘河红树林演替过程中的群落结构、物种组成、多样性变化及演替趋势的研究结果表明:(1)演替各阶段群落均由秋茄(Kandelia candel)、木榄(Bruguiera gymnorrhiza)、桐花树(Aegiceras corniculatum)、白骨壤(Avicennia marina)及老鼠簕(Acanthus ilicifolius)5个种类组成。(2)演替早期(4 a)群落高度增长较快,之后继续保持较快增长,至17 a时趋于稳定,之后增长速度缓慢。(3)4 a和17 a的群落立木级均分布在Ⅱ级—Ⅳ级,56 a和73 a的群落立木均达到最高级Ⅴ级,该两群落立木在Ⅱ级—Ⅴ级均有分布。(4)随着演替的进展,除了73 a群落盖度较56 a群落稍有下降外,其它演替群落盖度逐渐增加;群落胸高断面积表现出与盖度一致的变化趋势;群落个体密度则逐渐下降;群落物种多样性和均匀度不断提高,群落优势度则逐渐下降;群落相似性系数的变化表明在演替过程中群落物种组成结构没有发生明显变化。(5)群落变化及演替为:秋茄+桐花树群落→秋茄群落→白骨壤+秋茄群落→白骨壤群落。  相似文献   

4.
Until recently, parameters from microorganisms were generally not included in risk assessment at a comparable level to animals and plants. However, the major part of global biomass, biodiversity, and ecosystem processes is present in the microbial world and microbiological techniques applicable to risk assessment are becoming available. Two microbial indicators are described based on the usage of multiwell plates with different substrates and a redox indicator for monitoring mineralisation. With both techniques autochthonous microbial communities are analysed. Producing functional fingerprints of the microbial community gives insights into the composition of different functions. This is equivalent to observations of ecological abundance and species composition. When lack of reference sites or reference data renders risk assessment difficult, measurement of the pollution-induced community tolerance (PICT) can provide useful information.  相似文献   

5.
大石围天坑群孕育了极为丰富的植物多样性资源。为进一步了解大石围天坑群植物群落特征, 该文在天坑不同位置(坑口、坑腰、坑底)以及坑外共布设25个样地, 采用样方法进行调查, 共鉴定出269种维管植物, 隶属于89科176属, 群落物种组成数量较多的科主要有樟科、蔷薇科、荨麻科等。群落成层现象明显, 各层优势种分布较为均匀, 其中乔木层优势种主要有香木莲(Manglietia aromatica)、南酸枣(Choerospondias axillaris)、掌叶木(Handeliodendron bodinieri)等, 灌木层优势种有异叶梁王茶(Metapanax davidii)、滇鼠刺(Itea yunnanensis)等, 草本层以楼梯草属(Elatostema)占优势。群落季相明显, 以常绿、落叶阔叶混交林为主, 底部有常绿阔叶林分布, 坑口边缘小面积分布有落叶阔叶林; 群落生活型谱: 高位芽植物为55.76%, 地上芽植物为29.74%, 地面芽植物为6.69%, 隐芽植物为5.21%, 一年生植物为2.60%。该文分析了天坑植物群落类型、组成、结构等特征。  相似文献   

6.
陈国贵  王文卿  谷宣  洪伟  林宇枫  王瑁 《生态学报》2021,41(11):4310-4317
在城市化的背景下,探明不同大型底栖动物群落对植物群落变化的响应,对红树林生态系统的健康评价和退化生态系统的修复具有重要意义。以福建漳江口国家级红树林自然保护区为研究对象,揭示红树植物群落周转对不同大型底栖动物群落结构(蟹类和软体动物)的影响,并分析其与环境参数的关联性。结果表明:在1.6 km的地理尺度上,漳江口红树林湿地的环境变化较大,表现出7.19个环境梯度。在此地理尺度的环境梯度上,红树植物群落由5种红树植物组成,其平均周转率为76%;软体动物群落由12种软体动物以模块化和非随机的方式聚集,其平均周转率为83%,并随红树植物群落周转出现显著非线性增加,盐度和老鼠簕(Acanthus ilicifolius)周转是其主要影响因素;蟹类群落则由20种蟹类以更高的模块化和非随机的方式分散,平均周转率为89%,并随红树植物群落周转而呈线性增加,主要受pH和白骨壤(Avicennia marina)周转的影响。研究揭示了大型底栖动物与植物群落和环境之间的关系,为城市化背景下红树林生态系统的保护和恢复提供基础资料。  相似文献   

7.
Field trials were carried out from June to August in 2004 at Wuyishan (Wuyi Mountains), Fujian province, China, to determine the effects of habitat diversification on arthropod communities. Two Chinese cabbage, Brassica chinensis, field 1 (F1) and field 2 (F2) surrounded by diverse vegetable cultivars were selected, while a monoculture of Chinese cabbage served as the control field (CK). The results showed that: (i) when comparing insect abundance of each order between different habitats, significantly higher numbers of lepidopterous insects (39.76% from the each order) and lower densities of Hymenoptera (19.82%) were found in CK than in F1 and F2; (ii) compared with CK, F1 and F2 had a lower percentage of species richness and an abundance of herbivorous insects, but increased richness, abundance and biodiversity of predatory insects; (iii) no differences were observed in neutral insects' guild between different fields; and (iv) the dominant species for each guild depends on the habitat types and sampling dates. This study suggests that intercropping could conceivably be used in these habitats to increase the population of natural predators, thus achieving desirable and ecologically friendly results in vegetable fields.  相似文献   

8.
从植物群落组成和结构的角度研究森林群落的演替规律,是探究森林群落的退化与恢复过程及相关机制的重要途径,对于指导天然林保护和恢复具有重要理论价值和实践意义。2018年,对面积为9.6 hm~2的武夷山亚热带常绿阔叶林样地进行了第2轮调查,并从重要值、物种多度、物种丰富度、Shannon-Wiener多样性指数、Simpson指数、Margalef丰富度指数、Pielou均匀度指数、死亡率、补员率、种群大小变化率、相对适合度、胸径变异系数等角度分析了乔木层群落动态。结果表明:2018年的乔木个体为48科88属174种,较2013年增加了1种。Margalef丰富度指数上升,Shannon-Wiener多样性指数、Simpson指数、Pielou均匀度指数均略有下降。DBH≥1 cm的乔木个体从68336个减少到63897个,共死亡7430个个体,补员2991个个体。群落的年死亡率为2.30%,年补员率为0.96%,种群大小变化率为-1.34%,相对适合度为0.42。群落的平均胸径从5.02(±0.02) cm上升为5.49(±0.03) cm。28个重要值之和由71.92%下降为71.81...  相似文献   

9.
由于气候变化和人类活动的影响, 世界许多海区尤其是近岸海区发生了不同程度的低氧现象, 导致海洋动物大量死亡, 对海洋生态系统产生了不同程度的影响。为明确烟台牟平海洋牧场低氧对大型底栖动物的生态效应, 我们于2016年夏季(6月、8月、9月共3个航次)在该海域进行现场调查, 分析低氧对大型底栖动物群落时空变化的影响。结果表明: 牟平海洋牧场8月低氧事件发生时, 大型底栖动物群落的优势种为短叶索沙蚕(Lumbrinereis latreilli)、不倒翁虫(Sternaspis scutata)和内肋蛤(Endopleura lubrica)。低氧在一定程度上改变了大型底栖动物的群落结构, 表现为物种组成和优势种变化上。例如, 耐受低氧的机会种数量增加, 如短叶索沙蚕; 敏感种数量减少, 如微小海螂(Leptomya minuta)、长吻沙蚕(Glycera chirori)、大蝼蛄虾(Upogebia major)、极地蚤钩虾(Pontocrates altamarimus)、塞切尔泥钩虾(Eriopisella sechellensis)等。同时, 低氧也导致了物种多样性的降低, 但丰度和生物量受其影响不明显, 这主要是由于机会种短叶索沙蚕丰度和生物量的剧增所致。大型底栖动物不同物种耐受低氧的阈值不同。例如, 短叶索沙蚕在溶解氧(DO) < 1.0 mg/L受影响最大, 在DO = 2.0 mg/L时受到的影响不明显, 而其他敏感种如微小海螂、大蝼蛄虾、极地蚤钩虾、塞切尔泥钩虾等在DO < 2.5 mg/L时, 已表现出明显的不适。低氧事件之后, 大型底栖动物群落得到一定程度的恢复, 其恢复程度和需要的时间长短与低氧发生的程度有关。  相似文献   

10.
川西亚高山森林作为西南林区主体,是长江上游的生态屏障,该区域植被恢复方式主要为人工恢复和自然恢复,比较不同恢复方式下森林的物种组成和群落结构动态变化,对于川西亚高山森林恢复与重建有重要的意义,可以为制定合理的森林管理策略提供科学依据。基于茂县山地生态系统定位研究站不同恢复模式形成的的华山松人工林、油松人工林和自然恢复的次生林野外调查数据,分析了2005-2020年乔、灌、草三个层次的群落结构特征和多样性。结果表明:(1)不同恢复途径下,乔木层物种数都呈现增加趋势,华山松人工林、油松人工林、自然恢复的次生林乔木层物种数分别增加了11种、7种、8种;(2)华山松人工林中华山松重要值从48.06%降低到31.1%,乡土阔叶树种四川蜡瓣花进入乔木层,2020年重要值增大至21.62%,油松人工林中油松重要值逐渐降低,从43.59%降至29.76%;自然恢复的次生林中,乡土树种锐齿槲栎逐渐成为第一优势种,2020年重要值增至19.9%。(3) 华山松人工林、油松人工林和自然恢复的次生林中,温带区系成分分别占总属数的71.43%,80.77%和84%,温带区系特征明显。(4)华山松人工林和油松人工林乔木层径级结构均为偏正态分布;而自然恢复的次生林径级分布呈倒"J"形,以小径级个体为主。(5)不同林型的乔木层高度在15年间呈现增加的趋势,具体表现为油松人工林>华山松人工林>自然恢复的次生林。(6)乔木层Shannon-wiener指数和 Simpson指数均表现为自然恢复的次生林显著大于两个人工林,丰富度指数和均匀度指数表现为油松人工林最大;灌木层4个多样性指数均表现为油松人工林最大;草本层的丰富度指数、Shannon-wiener 指数和 Simpson 指数均表现为油松人工林较大,均匀度指数没有显著差异。结论:人工林恢复速度大于自然恢复的次生林,但自然恢复的次生林更新能力更强,且更有利于多样性的保存。两个人工林逐渐由常绿针叶林演替为以常绿针叶树为主的针阔混交林,自然恢复的次生林演替为以常绿阔叶树为主的针阔混交林。  相似文献   

11.
蒙古扁桃(Amygdalus mongolica)是中国珍稀濒危保护植物, 对植物区系进化、维持荒漠生态系统多样性与稳定性具有较高的学术价值和诊断意义。在宁夏境内设置14个样地, 利用样地调查法对蒙古扁桃群落组成进行了研究。结果表明: 蒙古扁桃群落记录到物种有74种, 隶属于28科53属; 生长型统计显示乔木2种, 灌木21种, 半灌木11种, 多年生草本36种, 一年生草本4种。依据TWINSPAN等级分类将14个蒙古扁桃样地划分为蒙古扁桃-草本荒漠、蒙古扁桃-半灌木荒漠2个群丛组和蒙古扁桃-戈壁针茅(Amygdalus mongolica - Stipa tianschanica var. gobica)、蒙古扁桃-猫头刺(Amygdalus mongolica - Oxytropis aciphylla)、蒙古扁桃-短花针茅(Amygdalus mongolica - Stipa breviflora)、蒙古扁桃-蓍状亚菊(Amygdalus mongolica - Ajania achilleoides)、蒙古扁桃-阿拉善披碱草(Amygdalus mongolica - Elymus alashanicus)、蒙古扁桃-蓍状亚菊+短花针茅(Amygdalus mongolica - Ajania achilleoides + Stipa breviflora) 6个群丛。该研究结果将为蒙古扁桃的保护和利用以及该群系植被志的编纂提供基础数据。  相似文献   

12.
海南万宁青皮林群落多样性特征研究   总被引:8,自引:0,他引:8  
根据样方调查,对海南万宁青皮林群落的种类组成、外貌、结构特征和物种多样性进行分析。结果表明:(1)海南万宁青皮林自然保护区有维管植物137种,隶属于62科110属,其中热带性分布种达95.5%,群落属于热带雨林植被类型中的海岸单优青皮群落。(2)群落的优势种为青皮,外貌常绿,生活型以小高位芽为主(占35.04%),青皮种群表现为增长趋势。(3)群落的物种丰富度Magarlef指数为34.30,Shannon-Wienner指数为2.31,Simpson指数为0.99,均匀度Pielou指数为1.08。(4)群落各层次的丰富度表现为乔木层>灌木层>藤本植物>草本层,Simpson指数表现为灌木层>草本层>藤本植物>乔木层,Shannon-Wienner指数表现为灌木层>藤本植物>草本层>乔木层,均匀度表现为草本层>灌木层>藤本植物>乔木层,表明乔木层的物种丰富度最高,但分布最不均匀,优势种的优势地位突出。  相似文献   

13.
The diel change in dissolved oxygen concentrations were recorded with an automated incubator containing a pulsed oxygen sensor in Sarasota Bay, Florida. The deployments occurred during a ‘pre-bloom’ period in May to June 2006, and during a harmful algal bloom dominated by Karenia brevis in September 2006. The diurnal (daylight) increase in dissolved oxygen concentrations varied from 16 to 104 μmol O2 l−1 with the corresponding nocturnal decrease in oxygen varying from 16 to 77 μmol O2 l−1. Nocturnal respiration consumed 42–113% of the diurnal net oxygen production with the minimum and maximum during the pre-bloom period. Hourly production rates closely followed fluctuations in irradiance with maximum rates in the late morning. Hourly oxygen utilization rates (community respiration) at night were highest during the first few hours after sunset.  相似文献   

14.
武汉天河机场地区蜘蛛群落及多样性研究   总被引:3,自引:0,他引:3  
刘家武  王国秀 《蛛形学报》2000,9(2):107-111
1999年7月-10月对天河机场地区4种生境的蜘蛛资源进行了调查,蜘蛛群落有12科34属52种。研究结果表明:群落的优势种为三突花蛛、锥腹肖蛸、茶色新园蛛、斜纹猫蛛、食虫沟瘤蛛、纵条蝇狮;不同生境、不同季节,群落结构组成不同;丰富度、多样性指数、均匀度、优势度不同;4种生境中的蜘蛛群落相似性很小。这主要与植被类型、密度等直接有关,另外也受农事活动的影响。  相似文献   

15.
Soil degradation has been found in urban forests in Shanghai, especially in the pure plantations. Mixed plantations are considered to improve soil quality because they can stimulate organic matter cycling and increase soil carbon and nutrient content. Although soil microbes play crucial roles in regulating soil biogeochemical processes, little is known about how mixed plantations affect soil microbial communities, including bacteria, archaea, and fungi. Here, we evaluated soil chemical properties, abundances and compositions of soil bacterial, archaeal, and fungal communities, and enzyme activities in pure and mixed Metasequoia glyptostroboides and Bischofia polycarpa plantations, located in Shanghai, China. The results showed that soil available phosphorus content in the mixed plantation of M. glyptostroboides and B. polycarpa was significantly higher than that in pure plantations, while no significant difference was observed in the content of soil organic carbon, total and available nitrogen, total and available potassium among the three studied plantations. We found higher fungal abundance in the mixed plantation, when compared to both pure plantations. Moreover, fungal abundance was positively correlated with the content of soil available phosphorus. No significant difference was found in the abundance and diversity of bacterial and archaeal community among the three studied plantations. A similarity analysis (ANOSIM) showed that mixed plantation significantly altered the community composition of archaea and fungi, accompanied with an increase of alkaline phosphatase activity. However, ANOSIM analysis of bacterial communities showed that there was no significant group separation among different plantations. Overall, results from this study indicated that fungal and archaeal communities were more sensitive to aboveground tree species than bacterial community. Moreover, mixed plantations significantly increased the activity of alkaline phosphatase and the content of soil available phosphorus, suggesting that afforestation with M. glyptostroboides and B. polycarpa is an effective way to alleviate phosphorus deficiency in urban forests in Shanghai, China.  相似文献   

16.
Successional changes of sessile organisms over about 3 years on concrete plates immersed at depths of 1.0, 2.5, 4.0 and 5.5 m in Nabeta Bay, Shimoda, Pacific coast of Japan, were investigated from their species composition, percentage cover, and the structure, metabolism, biomass and maturity of the community for the purpose of verifying the hypothesis of succession by Margalef (1968) and Odum (1969). The process of succession was divided into five stages from a cluster analysis based on Horn's (1966) similarity in community structure. The five stages were characterized from dominant, species and 18 community attributes in terms of structure, metabolism, biomass and maturity. With the advance of stages, two large-sized, long-lived species, the kelpEisenia bicyclis and the oysterCrassostrea nippona, dominated; 18 community attributes showed a directional succession ending in a constant community structure, low community metabolism, accumulation of community biomass except chlorophylla and an enhanced degree of community maturity. This directionality in succession of community attributes was valid for the prediction of Margalef and Odum, despite a tendency for estimated daily energy budget to be more heterotrophic in such an open system. From these results, it was suggested that the definition of succession by Odum (1969) should be interpreted as the regularity in shift of dominant species, not individual species, and as the control of system by feedback mechanism developing with succession rather than community-controlled mechanism.  相似文献   

17.
The Barber's Point, Oahu, Hawaii sewer outfall structure attracts large numbers of fish (500 — 1000 per 336 m2 bottom area) and fish species (23—29) not normally seen over flat, soft bottoms characteristic of the diffuser (66 m) isobath. Except for fish species strictly associated with corals, the adult fish community parameters (species richness, abundance, and composition) were similar to shallower natural Hawaiian reef environments. The adult fish species composition at the diffuser changed significantly during the discharge of heavy flocculated pre-treated sewage (15 mgd). High rates (15 mgd) of pre-treated sewage may cause decreases in total fish abundance and species richness when compared with the discharge of primary effluent with little or no flocculation between 0 and 19 mgd. Two fish species, which were generally abundant in Hawaiian waters during the years of observation, were absent at the outfall during discharge of heavy flocculated pre-treated effluent.  相似文献   

18.
19.
CASP (critical assessment of structure prediction) assesses the state of the art in modeling protein structure from amino acid sequence. The most recent experiment (CASP13 held in 2018) saw dramatic progress in structure modeling without use of structural templates (historically “ab initio” modeling). Progress was driven by the successful application of deep learning techniques to predict inter-residue distances. In turn, these results drove dramatic improvements in three-dimensional structure accuracy: With the proviso that there are an adequate number of sequences known for the protein family, the new methods essentially solve the long-standing problem of predicting the fold topology of monomeric proteins. Further, the number of sequences required in the alignment has fallen substantially. There is also substantial improvement in the accuracy of template-based models. Other areas—model refinement, accuracy estimation, and the structure of protein assemblies—have again yielded interesting results. CASP13 placed increased emphasis on the use of sparse data together with modeling and chemical crosslinking, SAXS, and NMR all yielded more mature results. This paper summarizes the key outcomes of CASP13. The special issue of PROTEINS contains papers describing the CASP13 assessments in each modeling category and contributions from the participants.  相似文献   

20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号