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1.
洞庭湖底栖动物种类分布及水质生物学评价   总被引:24,自引:0,他引:24       下载免费PDF全文
1 995年枯水、平水、丰水期对洞庭湖设 6个断面进行采样 ,共采到底栖动物 58种 ;其密度变幅为 78~ 544 .5个 /m2 ;1 0种常见种均成聚集分布。采用综合生物污染指数评价水体质量 ,结果显示洞庭湖整体水质受到轻度污染 ,评价结果与化学污染指数评价结果一致 ;各采样断面综合生物污染指数均明显大于 1 981~ 1 982年的测量结果 ,表明水体质量变差  相似文献
2.
长江口底栖动物功能群分布格局及其变化   总被引:23,自引:3,他引:20       下载免费PDF全文
袁兴中  陆健健  刘红 《生态学报》2002,22(12):2054-2062
用功能群方法对长江口南岸潮滩底栖动物与河口环境梯度和生境变化的关系进行了研究。根据底栖动物的取食类型,运动能力和摄食机制进行了功能群的划分。共鉴别出55种栖动物,并将其划分为15种功能群类型,均表现出沿长江口南岸河口梯度的逐渐变化的分布格局,底栖动物物种数和功能群类型数主要表现出与河口盐度梯度呈正相关的动物地理分布格局,沿着河口梯度,不同的采样断面,优势功能群不同。在河口下游,功能群类型多样化,各种食性类型,不同运动能力及各种摄食机制抽功能群皆有;而生境较单一的河口上游和受污染较严重的断面,功能群类型较少,沿着河口梯度,最显著的变化是固着生活和以触手摄食的功能群的迅速消失,底栖动物功能群多样性是对河口环境梯度和生境质量的综合反映。  相似文献
3.
洪湖底栖动物群落结构及其对水质的初步评价   总被引:18,自引:0,他引:18  
作者在1988-1989年对洪湖4次采样中共发现底栖动物71种(属),其中软体动物20种,寡毛类10种,水生昆虫26属,甲壳纳,蛭纲等种15种。洪湖底栖动物现存量在湖内的不同区域间存在较大的差异,其季节波动亦明显。洪湖底栖动物全年平均为502ind,/m^2,35.47g/m^2。作者利用底栖动物群落结构进行水质的生物学评价,认为洪湖水体受到轻一中度程度有机污染。另外,水质的化学测定与生物学评价一  相似文献
4.
火溪河底栖动物现状及水质评价   总被引:14,自引:0,他引:14  
1996年8月,11月各一次调查火溪河的底栖动物。共采集到到底栖动物39种,其数量为87.3ind/m^2,优势种类为方巢石蚕、四节蜉、小蜉、光石蝇和溪在非议 五种。火溪河底栖运行具有明显的山地型、流水型特点、时空分布一致。应用BMWP记分,BBI/FBI生物指数和Syannon多样性指数对脂河水质进行评价,表明水质清洁。作者建议以方巢石蚕70.0ind/m^2作为火溪河水质清洁与轻污的一个界定值  相似文献
5.
河蟹过度放养对湖泊底栖动物群落的影响   总被引:13,自引:0,他引:13  
通过对河蟹养殖的代表湖泊黄湖与参照水体即黄湖围栏外、天然捕捞湖泊龙感湖以及鱼类放养湖泊牛山湖的比较研究 ,探讨河蟹过度放养对湖泊底栖动物群落结构和功能的影响。结果表明 ,河蟹影响底栖动物群落的途径有两条 ,一是直接摄食 ,二是破坏沉水植物的间接作用。在蟹苗放养强度约 1kg·hm-2 的条件下 ,底栖动物的种类多样性明显下降 ,密度和生产量减少 6 0 %以上 ,其中对小型螺类的影响尤甚。作者认为目前最适的养殖模式应是河蟹与非草食性鱼类的轮作经营。  相似文献
6.
《Hydrobiologia》1990,(1):241-250
A biomanipulation experiment was carried out in the eutrophic lake, Frederiksborg Slotss? (Denmark). During 1987 and 1988, densities of roach (Rutilus rutilus) and bream (Abramis brama) were reduced, using seine and pounding nets, and large-sized perch (Perca fluviatilis) were added instead. Nutrients, oxygen, phytoplankton, zooplankton, fish and zoobenthos were measured two years after the manipulation and compared with results obtained two years before the manipulation. A total amount of 6524 kg wet weight of roach and bream was removed. Roach and bream constituted 45% of the total fish biomass after the reduction, compared with 78% before the manipulation. Recruitment of roach decreased, and mortality rates of young-of-the-year perch were lower after the fish reduction. After the manipulation, decreases in phytoplankton biomass coincided with increases in zooplankton biomass during spring and autumn periods, although, the mid-summer level of the biomass of cyanobacteria did not change. Inorganic nutrients generally increased, but no significant changes were found, either in the oxygen budget or in the community structure or quantitative distribution of zoobenthos after the fish manipulation. Although the effects of the fish manipulations were not as pronounced as those found in lakes with lower nutrient regimes, the results indicate positive changes in the water quality. Nevertheless, it is probably necessary to continue a fish reduction programme to maintain or further improve the water quality.  相似文献
7.
2003年8月到2004年8月对长江三峡水库香溪河库湾的底栖动物进行了定量研究。共采到底栖动物26种,隶属4门6科,总平均密度为276ind./m2,总平均生物量为0.301g/m2,优势种为霍甫水丝蚓和前突摇蚊幼虫。与其他同类型的水库比较香溪河库湾的现存量相对较低。研究结果同时显示随着蓄水时间的延长,底栖动物的现存量在逐渐增加。霍甫水丝蚓和前突摇蚊幼虫等耐污种发展为优势种,表明水质有恶化的趋势,寡毛类的平缓发展说明目前香溪河库湾的沉积情况尚不严重。  相似文献
8.
9.
Modelling production and biomasses of zoobenthos in lakes   总被引:5,自引:0,他引:5  
This work presents a dynamic model to predict zoobenthos in lakes. The model has been developed within the framework of a more comprehensive lake ecosystem model, LakeWeb, which also accounts for the following functional groups of organisms, phytoplankton, bacterioplankton, two types of zooplankton (herbivorous and predatory), macrophytes, prey fish and predatory fish. This work also presents a new data-base for zoobenthos in lakes. Many of the lakes included in this study are situated in the former Soviet Union. They were investigated during the Soviet period and those results have been largely unknown in the West. Using this data-base, this work also presents new empirical models for zoobenthos. The new dynamic model gives seasonal variations (the calculation time, dt, is 1 week using Euler's method and enough iterations to get stable solutions). The basic aim of the dynamic model is that it should capture general functional and structural patterns in lakes. We have demonstrated by several model tests along limnological gradients (total phosphorus concentrations, pH, lake colour, latitude and lake size) that the dynamic model gives predictions that agree well with the values given by the empirical regressions, and also expected and requested divergences from these regressions when they do not provide sufficient resolution. It would have been very difficult indeed to carry out such tests regarding ecosystem responses using traditional methods with extensive field studies in a few lakes. We have given algorithms for (1) production of zoobenthos from eating macrophytes, benthic algae and sediments, (2) elimination (related to the turnover time of zooplankton), and (3) zoobenthos consumption by prey fish, and the factors influencing these processes/rates. The model is driven by data easily accessed from standard monitoring programs or maps a prerequisite for practical utility in contexts of lake management.  相似文献
10.
Recent sediments of the North American Great Lakes are inhabited by numerous species of macrobenthos which alter the physical and chemical properties of sediments and modify interface transport characteristics. Distributions of such radionuclides as cesium-137, lead-210, and isotopes of plutonium exhibit a zone of constant activity extending down from the sediment-water interface from 1 to 15 cm. Recent studies have confirmed that radiometrically determined mixed depths are consistent with the vertical distribution of oligochaete worms and the amphipod,Pontoporeia hoyi. Generally, 90% of the benthos are contained within the radiometrically defined mixed zone. Where comparisons are possible, rates of sediment reworking by ‘conveyor belt’ species are comparable to or exceed sedimentation rates. Systematic variations in the mixed depth occur within depositional basins with greatest depths tending to be associated with least consolidated, organically rich materials. A quantitative steady-state mixing model accounts satisfactorily for observed radioactivity and heavy metal profiles. Bioturbation appears to be an important process, limiting the resolution with which historical records of particle-associated contaminants may be reconstructed from sediment cores. As bioturbation serves to maintain contact of contaminated sediments with overlying water, this time may also characterize the long-term lake recovery for contaminants removed by burial. As the time varies with location, a mean for an entire lake is not well known, but is on the order of 20 years for Lake Huron. Contribution No. 300 of the Great Lakes Environmental Research Laboratory, Ann Arbor, Michigan.  相似文献
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