科尔沁沙地人工固沙群落草本植物种群生态位特征   总被引：4，自引：0，他引：4  

李明  蒋德明  押田敏雄  周全来  骆永明 《草业科学》2009,26(8):10-16

运用Levins生态位宽度和Pianka生态位重叠公式,计测分析了科尔沁沙地流动沙丘以及山竹子Hedysarum fruticosum、柠条锦鸡儿Caragana korshinskii、黄柳Salix gordejevii和小叶锦鸡儿C. microphylla人工固沙群落内草本植物种群的生态位宽度和生态位重叠。研究结果表明：在不同的生境条件下物种的生态位宽度存在差异,沙蓬Agriophyllum squarrosum在流动沙丘上的生态位宽度最大,狗尾草Setaria viridis、毛马唐Digitaria ciliaris分别在山竹子群落和黄柳群落中的生态位宽度最大,烛台虫实Corispermum candelabrum在柠条锦鸡儿群落和小叶锦鸡儿群落中占据着最宽的生态位。各群落中生态位宽的物种对生态位重叠值较大,但有些较窄的生态位物种对之间也出现较大的生态位重叠,这种现象从另外的角度表明各群落内环境资源存在一定的空间异质性。不同固沙群落中相同物种的生态位宽度和生态位重叠的差异在一定程度上反映了各群落内不同的区域环境特征。  相似文献   

生态位   总被引：3，自引：0，他引：3  

宋丁全 《金陵科技学院学报》2006,22(3):1-4

生态位是生态学中的一个重要概念.阐述了生态位的基本概念,综述了生态位理论形成与发展的过程,给出并分析了生态位宽度、生态位重叠及生态位分离的常用度量公式,为完整的理解和应用生态位理论提供了捷径.  相似文献   

Analysis of food preference and competition based on stomach contents of fish species inhabiting fresh and brackish waters in South Korea     

Chang Woo Ji  Dae-Seong Lee  Da-Yeong Lee  Young-Seuk Park  Ihn-Sil Kwak 《Ecology of Freshwater Fish》2023,32(1):64-79

We analysed the stomach contents of fish species inhabiting fresh and brackish waters of South Korea to improve our understanding of feeding preferences and competition among them. The stomach contents of 54 fish species contained 237 genera, 187 families, 84 orders, 37 classes and 25 phyla. Faunal food items included 164 genera, 129 families, 47 orders, 23 classes and 16 phyla. Floral food items were relatively limited, comprising 73 genera, 58 families, 37 orders, 14 classes and nine phyla. The most consumed faunal food item was Chironomidae (Diptera), whereas the most consumed floral food item was Fragilariaceae (Fragilariales). The 54 fish species were classified into six groups using hierarchical and nonmetric multidimensional analysis based on their food preferences: Group 1 (G1) fishes were zooplanktivores; group 2 (G2) fishes mainly consumed Malacostraca, Maxillopoda and other fishes (e.g. Osmeriformes); groups 3 (G3) and 4 (G4) consumed Chlorophyta, Cyanobacteria and Bacillariophyta; and groups 5 (G5) and 6 (G6) consumed macroinvertebrates. Network analysis was used to link fishes with their food items. The highest hub score for food items was for macroinvertebrates, including Diptera (13.9), Ephemeroptera (11.1) and Trichoptera (8.2). Niche breadth analysis represented the diversity of food items among the feeding groups (G1–G6). Food item diversity was high for planktivores (G1 and G3) and omnivores (G4). Conversely, the dietary diversity of carnivores (G2) and insectivores (G5) was limited. Competitive relationships between fishes, as represented by the niche overlap in G5 (insectivores), were higher than those between other groups.  相似文献   

Do fish isotopic niches change in an Amazon floodplain lake over the hydrological regime?     

Lucas Silva Azevedo  Incio Abreu Pestana  Marcelo Gomes Almeida  Wanderley Rodrigues Bastos  Cristina Maria Magalhes Souza 《Ecology of Freshwater Fish》2022,31(1):72-80

Floodplain lakes are ecosystems characterised by annual flood and dry cycles. Fish ecology is influenced by the flood pulse due to the large influx of allochthonous food resources and diversification of habitats during the flood cycle, while during the dry cycle, fishes tend to be confined in reduced habitat. The aim of this study was to evaluate the seasonal variation in trophic niche width and overlap of four species—Mylossoma duriventre, Prochilodus nigricans, Cichla.pleiozona and Serrasalmus rhombeus—in an Amazonian floodplain lake. Stable isotope analyses were used to estimate trophic niche width and overlap during the flood and dry seasons. We hypothesised broader niche width for all species during the flood cycle and a higher degree of overlap between the two piscivorous fishes during the dry cycle. Isotopic niche width was 72% broader for P. nigricans, 61% for S. rhombeus and 54% for C. pleiozona during the dry cycle, which did not support our hypothesis. Core niche width overlaps were not observed between piscivorous species in either flood or dry cycle. The results indicate that seasonal variation in isotopic niche width is specific to feeding habit. Understanding how fish trophic ecology responds to changes in the hydrological regime during the seasons is crucial for sustainable fishery management in a region where many people rely heavily on fish for nutritional and economic purposes.  相似文献   

黔西北铅锌矿废渣场优势草本植物种群生态位及种间关系     

宋红艳  孙彩丽  柴宗政 《草地学报》2022,30(10):2764-2771

本研究以黔西北铅锌矿废渣场为研究区，对矿渣堆及周边区域16种优势草本植物共有种生态位与种间联结性进行对比分析，以期为矿区生态恢复提供科学依据。结果表明：知风草(Eragrostis ferruginea)、狗尾草(Setaria viridis)、细柄黍(Panicum psilopodium)、鼠尾粟(Sporobolus fertilis)和牛筋草(Eleusine indica)等禾本科和艾蒿(Artemisia argyi)等菊科植物有较高的重要值和生态位宽度，分布相对广泛；禾本科植物如知风草、狗尾草、细柄黍、鼠尾粟和牛筋草等，因生态位相似且对重金属适应能力强，故生态位重叠度较高；矿渣堆和周边区域优势草本植物共有种总体均呈显著正联结，但种对间却以负联结为主，表明该矿渣场植物群落演替总体呈现进展演替，但演替进程缓慢，仍处于演替初期阶段。综上，矿渣堆因富集重金属而影响着区域植物群落构建；生态治理中，应将禾本科知风草、狗尾草、细柄黍等植物作为先锋植物，促进植被恢复。  相似文献   

Feeding ecology and coexistence dynamics in a community of fishes in a temperate temporary water body     

Muoz-Campos M. Tessy  Valdez-Carbajal Sharon  Domínguez-Castanedo Omar 《Ecology of Freshwater Fish》2022,31(1):1-16

Temporary water bodies are temporally variable ecosystems supported primarily by rainwater. The biota supported by such water bodies present a range of capacities to remain in this environment for all or part of their life cycles. During floods, temporary pools can connect with permanent streams, promoting changes in trophic networks in the aquatic food webs. The aim of this research was to analyse the feeding ecology of a fish community in a temporary pool near of Tlacotalpan, in the Mexican southeast, in order to understand the dynamics of the feeding habits. First, we identified feeding habits that can be interpreted as guilds of the fishes in the temporary pool: the annual killifish Millerichthys robustus (the only autochthonous species) is planktophagous; Cynodonichthys tenuis and Astyanax aeneus are insectivores; Dormitator maculatus and larvae of amphibians (Lithobates sp.) are mainly detritivorous; and Poecilia mexicana is planktophagous and insectivorous. We then estimated the effect of coexistence on niche breadth and overlap. The niches of M. robustus and P. mexicana evidenced overlap, but the breadth was adjusted inversely, suggesting feeding specialisation in M. robustus in response to competition. We documented the existence of two cohorts of M. robustus; the niche breadth of the first and second cohorts suggesting different strategies probably related to competition under variable conditions. The niche of C. tenuis and A. aeneus, and D. maculatus and tadpoles overlapped, following a pattern of feeding generalisation in response to competition.  相似文献   

基于碳氮稳定同位素的太湖鱼类营养生态位研究          下载免费PDF全文

刘素群  申明华  刘学勤 《水生态学杂志》2023,44(5):76-83

为探究太湖鱼类的营养生态位特征，于2019~2020年开展了太湖鱼类的碳氮稳定同位素调查，分析了鱼类营养生态位大小、生态位重叠度及营养级。研究结果表明，鱼类δ13C值范围为-27.67‰~-17.92‰，δ15N值范围为6.02‰~20.31‰。营养生态位大小（SEAc值）范围为0.14‰2~20.43‰2，其中黄颡鱼的生态位最大，光泽黄颡鱼的生态位最小。短颌鲚、陈氏短吻银鱼和鲢的SEAc值均较小，表明他们利用的食物源和生境范围较窄，鳙的SEAc值较大，表明其利用的食物源和生境范围较广。鱼类的营养生态位重叠度为0~70.6%。大银鱼与翘嘴鲌的生态位重叠度最大（70.6%），其次为鲈与翘嘴鲌（39.9%），其余物种间的生态位重叠度范围为0~38.9%。短颌鲚与其他肉食性鱼类的生态位重叠度较小，表明他们之间的食物资源竞争较弱。陈氏短吻银鱼与鲢、鳙在生态位上存在明显的分离，这与陈氏短吻银鱼专食浮游动物有关。鱼类营养级范围为0.73~3.62，鮠一种的营养级最高，泥鳅的营养级最低。分析表明，鱼类营养生态位的大小与其摄食的食物种类以及对不同生境的利用程度有关；大部分鱼类间生态位重叠度较低，表明鱼类在资源利用上存在较大分离。本研究结果也为太湖鱼类食物网分析及渔业资源管理提供了基础数据。  相似文献   

燕山北部板栗林下杂草群落动态及生态位研究          下载免费PDF全文

李娟  张昱 《水土保持学报》2022,36(3):201-206

为准确掌握燕山北部板栗园杂草的发生现状及群落组成,分别于2017年、2018年、2020年对燕山北部板栗林下杂草的种类、数量等进行调查,并运用Levins生态位指数和Pianka生态位重叠指数分析板栗林下优势杂草的生态位动态及群落对资源的利用情况和种间竞争情况。结果表明:(1)2017年、2018年、2020年燕山北部板栗林下杂草群落中分别有53种(27科48属)、47种(24科43属)和44种(24科41属)植物。其中优势杂草15种。(2)15种优势杂草中,葎草和灰绿藜占据较宽的生态位,它们对环境资源利用的多样性程度比较高。鸭跖草、艾蒿、狗尾草、茜草、苦荬菜、白屈菜、紫花地丁、灰绿藜、毛地黄和野大豆等物种对资源的利用能力在逐步增强。(3)杂草群落中生态位重叠值＜0.2的优势物种种对数明显减少,优势杂草物种在逐渐增加对周边资源环境充分利用的能力,灰绿藜逐渐取代葎草的优势地位,进而导致种间竞争关系更加复杂,群落向更高级更合理利用环境资源的群落方向演替,逐步形成更加复杂的种群结构。因此,准确掌握板栗园杂草的发生现状、优势种群及群落组成,可为燕山北部板栗林下杂草的针对性防治提供理论依据。  相似文献