Study on zooperiphyton and zoobenthos of a small river

The special traits of zooperiphyton and zoobenthos structures in a small river were studied. Under conditions of maximal proximity of niches, these groups of invertebrates retain taxonomic and ecological heterogeneity. Differences in zooperiphyton and zoobenthos taxonomic structures are most pronounced in terms of presence of dipterans, oligochetes, and mollusks. In the periphyton, the dominant groups are chironomid (orthocladines, chironomines, and tanitarsines) larvae, oligochetes of fam. Naididae and mollusks of fam. Limnaeidae. In the benthos chironomid (chironomines and tanirodines), oligochetes of fam. Tubificidae, and mollusks of fam. Pisidiidae are dominant. On average, the bottom invertebrates are considerably larger than fouling organisms. At similar abundance values, the biomass of benthos is by an order of magnitude higher compared to zooperiphyton. Ranging of average biomasses of zooperiphyton and zoobenthos revealed that the leader common for both communities is the large and mobile predatory leech, Erpobdella octoculata (Linnaeus). The anthropogenic impact and zoogenic (beavers) impact upon the river biota are comparable to each other.     

Phytophilous zoocoenoses of Lake Teletskoye

The composition, structure, and spatial distribution of zoobenthos and zooperiphyton at plantfilled regions of the littoral of Lake Teletskoye have been analyzed. The dependence of the taxonomic composition, number, and biomass of zoobenthos on vegetation type has been discovered. A multilevel character of the distribution of invertebrates in macrophyte overgrowths has been shown. An analysis of the trophic structure of the communities of macroinvertebrates revealed the predominance of algodetritophagous animals in zooperiphyton. The role of plant overgrowth as a “life concentrator” in an oligotrophic lake has been revealed.     

On the interrelation of diversity and structural and functional indicators of hydrobiont communities

Empirically derived relationships between indicators of diversity of zoobenthos, zooperiphyton, and zooplankton and the structural characteristics of communities in reservoirs of various types are presented. The relationships between indicators of diversity, the biomass of communities, the spatial structure, and the ratio of energy stored in biomass and scattered energy have been elicited.     

Spatial structure of zooperiphyton in a small river (West Siberia)

Basic quantitative characteristics of zooperiphyton from the Uk River are presented. Factors effecting the composition and structure of invertebrates have been found. The effect that the current velocity, water level, and different types of pollution have on zooperiphyton in the small river is shown. The pollution of the river reduces taxonomic diversity. The maximum effect is caused by the discharge of mineralized waters. In clean portions of the river, Trichoptera dominate in biomass; in polluted parts, their role decreases and the larvae of chironomids and leeches prevail in zooperiphyton.     

Spatial structure of zooperiphyton from the Ob River

Data on the qualitative and quantitative composition of zooperiphyton in the middle and lower reaches of the Ob River are reported, revealing the basic factors affecting its growth. Along most of the river, the zooperiphyton forms a continuum, which is disturbed at sites exposed to pollution. It is found that communities dominated by caddisworms prevail over most of the river; a decrease in the river stream velocity causes a change in the communities, with the replacement of Trichoptera by gastropod communities.     

Changes in the zooperiphyton structure in a small river along the spatial gradient

A total of 165 taxa have been recorded in the zooperiphyton of the Sestra River, among which larvae of chironomids (40), nematodes (24), and oligochaetes (21) have the highest species richness. The increase in the taxonomic richness of zoocenoses from the river head to its mouth is weakly expressed. The highest diversity of zoocenoses is characteristic for the contact zones of the river water with its tributaries and receiving waters. The discreteness of spatial characteristic of the taxonomic composition of zooperiphyton reflects the heterogeneity and diversity of habitat conditions of invertebrates. In regards to its effect on zoocenoses, anthropogenic pollution can exceed the impact of many environmental factors (including the current velocities) which affect the formation of rheophilic communities in river ecosystems. The dominant complexes of zooperiphyton include all trophic groups of invertebrates, among which the group of detritophages-collectors has the highest taxonomic diversity. The group of phytodetritophages-filterers + collectors mainly includes chironomid larvae of the genus Chironomus, which are associated with strongly polluted zones. Invertebrate filterers, sponges, and bryozoans prevail mainly in zooperiphyton in the lower reaches of the river, which are not subjected to the pollution.     

拒马河原生动物和底栖动物初步调查及水质分析

2003年3月和4月,对拒马河(北京段)的原生动物及底栖动物群落结构和物种多样性进行了调查分析,并且就其水质现状及水生动物种类和数量变化对环境污染的指示意义加以探讨。共鉴定出原生动物125种,底栖动物17种。结果表明,拒马河水生动物种类较为丰富,物种多样性高,水质生物指标综合评价拒马河水体受到轻度和中度污染。此外,通过对软体动物、环节动物、水生昆虫在不同站点分布的差异分析,表明河流水体污染可导致底栖动物多样性明显降低。从水生生物指示种的变化,可预测水质的变化。     

Allochthonous Organic Matter Supports Benthic but Not Pelagic Food Webs in Shallow Coastal Ecosystems

Rivers transport large amounts of allochthonous organic matter (OM) to the ocean every year, but there are still fundamental gaps in how allochthonous OM is processed in the marine environment. Here, we estimated the relative contribution of allochthonous OM (allochthony) to the biomass of benthic and pelagic consumers in a shallow coastal ecosystem in the northern Baltic Sea. We used deuterium as a tracer of allochthony and assessed both temporal variation (monthly from May to August) and spatial variation (within and outside river plume). We found variability in allochthony in space and time and across species, with overall higher values for zoobenthos (26.2 ± 20.9%) than for zooplankton (0.8 ± 0.3%). Zooplankton allochthony was highest in May and very low during the other months, likely as a result of high inputs of allochthonous OM during the spring flood that fueled the pelagic food chain for a short period. In contrast, zoobenthos allochthony was only lower in June and remained high during the other months. Allochthony of zoobenthos was generally higher close to the river mouth than outside of the river plume, whereas it did not vary spatially for zooplankton. Last, zoobenthos allochthony was higher in deeper than in shallower areas, indicating that allochthonous OM might be more important when autochthonous resources are limited. Our results suggest that climate change predictions of increasing inputs of allochthonous OM to coastal ecosystems may affect basal energy sources supporting coastal food webs.     

Basic characteristics of zooperiphyton in large rivers of Western Siberia (Tyumen oblast)

The data on the qualitative and quantitative composition of zooperiphyton from seven large rivers of Western Siberia are presented. The species similarity of zooperiphyton has been documented in most of the rivers. The biomass in unpolluted parts is mainly formed by the larvae of caddis flies. Factors which effect the composition and structure of zooperiphyton have been determined. Changes in the structure and quantitative development of zooperiphyton are shown.     

Amino acid composition of epilithic biofilm and benthic animals in a large Siberian river

相似文献   

淀山湖周丛动物群落的初步研究

作者于1991年11月至1992年11月对淀山湖水生植物上周丛动物进行了初步研究。共观察到84种周丛动物,以原生动物(38.10%)和轮虫(22.62%)占多数。按个体大小,分为小型周丛动物群落和大型周丛动物群落两种群落类型。小型周丛动物群落的优势种为似钟虫、角突臂尾轮虫等,个体数量受周丛原生动物支配,一年中有两次高峰(3-4月份和11月份),生物量在3月份最大,主要受周丛轮虫控制。大型周丛动物群落的优势种为线虫和螺类,一年只有一次数量高峰(6-8月),生物量中螺类占绝对优势(96.4%)。周丛动物在不同水生植物上的分布数量不同,沉水植物中以金鱼藻最多,大茨藻最少;并且叶上的数量明显高于茎上。漂浮植物上一般多于沉水植物,且根部最多,茎、叶相近。水生植物上周丛动物多为广布种,特有种罕见,主要出现于小型周丛动物群落中。       

滆湖底栖动物群落的时空变化及水质生物学评价

2009年5月-2010年2月对滆湖底栖动物群落进行了调查,并根据底栖动物群落结构对水质进行了生物学评价。结果表明:采集到底栖动物共35种,隶属于3门25属;优势种类为中国长足摇蚊(Tanypus chinensis)、霍甫水丝蚓(Limnodrilus hoffmeisteri)、苏氏尾鳃蚓(Branchiura sowerbyi)、克拉泊水丝蚓(L.claparedeianus)、中华河蚓(Rhyacodrilussinicus);滆湖底栖动物的年均密度为374.1ind·m-2,寡毛类对密度的贡献最大,占年均密度的77.4%,最大密度出现在夏季,春季最低,St14年均密度高于其他站点;滆湖底栖动物的年均生物量为17.78g·m-2,软体动物对生物量的贡献最大,占年均生物量的97.4%,夏季生物量最大,冬季最低,St14年均生物量明显高于其他各个站点;底栖动物的密度和生物量随季节变化明显,密度的季节变化表现为夏季>秋季>春季>冬季,生物量变化表现为夏季>春季>秋季>冬季;Shannon-Wiener多样性指数值(H’)、Margalef多样性指数值(D)、Pielou均匀度指数值(J)和BI指数值表明滆湖水体处于中度到重度污染状态。     

The radioactive contamination dynamics of water body ecosystems of different types in the Chernobyl atomic station alienation zone in Belarus

The long-term (1986-2005) gamma-activity dynamics in dominating zoobenthos species and the bottom sediments in the inlet of Pripyat river and the non-flowing Perstok lake within the Chernobyl alienation zone was determined. Immediately after the accident (1986-1987) zoonehthos y-activity achieved the maximal values (up to 300-1100 kBq/kg) and after that began to decline steadily due to natural decay of man-caused radionuclides of "Chernobyl origin". Up to summer 2005 gastropod mollusks gamma-activity (Lymnaea stagnalis, Viviparus viviparus) approached to the natural level (less than 6 Bq/kg) in the inlet of Pripyat river, but it remained at the very high level up to 979-1638 Bq/kg in the Perstok lake. The positive correlation between gamma-activity of mollusks and bottom sediments has been established. In turn, the long-term variations of atmospheric precipitate amounts which wash down radionuclides from surrounding territories to water bodies and the amounts of annual flow of the Pripyat river as well as shoreline position changes in water bodies within the Chernobyl alienation zone influence on these values too.     

Taxonomic and trophic structures of dominants in the zooperiphyton of waterbodies and watercourses of the upper Volga basin

All the main trophic groups of invertebrates are presented in the compositions of dominant assemblages of zooperiphyton in the studied waterbodies and watercourses. The strong pollution of water by suspended solids of anthropogenic origin in the water of the upper Volga reservoirs leads to the suppression of typically sessile filter-feeding invertebrates (sponges, bryozoans, and Dreissena) able to form the highest biomass of zooperiphyton using natural food items. The conditions of the disturbed structure of food resources are favorable for the development of detritivores-gatherers. In small rivers receiving industrial wastewaters, excessive amounts of food in the water column and in the form of sediments on the substrates suppresses invertebrates-biofowlers and facilitates the expansion of the benthic larvae of chironomids of g. Chironomus (combining the filtration and gathering of food particles on the substrates) to the vacant spatial niches. At the same time, the role of nematodes and oligochaetes with prevailing detritophages increases. In the acidified lakes of the Darwinsky National Reserve, the decrease in the total species diversity of zooperiphyton is accompanied by decreases in the role of filter-feeding invertebrates. The chironomid larvae and oligochaetes prevailed in the poor zoocenoses. The roles of predatory caddisfly larvae, black gnats, and nematodes increased. The labile structural characteristics of zooperiphyton with the conservation of the historically formed methods of foraging are the main modern way that biofouling communities adapt to changes in the quality and quantity of food resources upon modern anthropogenic pollution of the aquatic environment.     

以底栖动物评价湘江污染的研究

湘江底栖动物种类较丰富,而上游种类尤多,生物多样性明显。中、下游某些江段因污染等因素影响,多样性有差异。shannon多样性指数反映出了这些变化。上游江段属于清洁水体,中、下游多数江段属于轻污染,少数江段为中污染,而霞湾港江段为重污染。进行了水和底泥中化学毒物的含量与生物主要种类的数量变化的相关分析。       

Prognostic radioecological mathematical model of the Yenisei river

A one-dimensional mathematical model of the Yenisei river ecosystem including hydrological, ecosystem and radioecological blocks has been developed. The model was used to evaluate contribution of different processes (transfer by water masses, dilution, radioactive decay, bioaccumulation) into self-purification of the river water from a radiation pollution and calculate pollution density of ecosystem components (bacteria, phyto-, zooplankton, phyto-, zoobenthos, detritus) with 137Cs and 32P.     

Modelling production and biomasses of zoobenthos in lakes

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.     

Studies of aquatic insects in the Atna River 1987–2002

River Atna is situated in south-eastern Norway and stretches from approx. 1400 m a.s.l. in the Rondane Mountains, through Lake Atnsjøen, at 701 m a.s.l.; to the confluence with River Glomma at 338 m a.s.l. The catchment area is 1323 km², oligotrophic and very susceptible to acid precipitation. The river water is very poor in nutrients and ions, and pH varies from 5.0 to 7.2. Samples were taken each year from 1987 to 2002 at three to five localities from 1280 to 380 m a.s.l. Insect larvae were collected by Surber sampling and by kick sampling. Malaise traps were used to collect adults of Plecoptera, Trichoptera, Chironomidae and Limoniidae. A total of 16 taxa of Ephemeroptera, 24 taxa of Plecoptera, 39 taxa of Trichoptera, 125 taxa of Chironomidae and 52 taxa of Limoniidae, were identified. Our results from Atna provide some support for a zonation of the river based on zoobenthos. The occurrence and abundance of functional groups among the Plecoptera, Trichoptera, and Chironomidae are discussed in relation to the River Continuum Concept (RCC). Our conclusion is that grazers dominate in the zoobenthos in streams in the treeless alpine region in Norway. Natural lakes, which occur in most watercourses in Norway, appear to cause a disturbance in relation to the original RCC concept, as the zoobenthos community in and below the lake outlet is dominated by collectors (filter feeders). The pattern found in the Atna watercourse is probably a general pattern for a northern watercourse in the Holarctic, where the glacial periods created lakes in most watercourses. The results of the long term sampling in Atna are discussed in relation to the practicalities and the cost-benefit of zoobenthos in efficient bio-monitoring in rivers.     

Estimation of transfer of technogenic radionuclides in food chains of the Yenisei river

The efficiency of the transfer of gamma-emitting radionuclides in food chains, including macrophytes, zoobenthos, and bentho- and ichthyophagist fish, was estimated in the radiation-polluted region of the Yenisei river. Significant differences in the efficiency of the transfer of natural and technogenic radionuclides between components of different trophic levels were revealed. Substantial species-related differences in the accumulation of radionuclides in ichthyophagist fish from food were revealed.     

Specific features of the feeding of juvenile atlantic salmon (<Emphasis Type="Italic">Salmo salar</Emphasis> L.) in the subarctic varzuga river and its small tributaries (Kola Peninsula)

An analysis of the spectrum and intensity of salmon parr feeding and the structure and abundance of zoobenthos in the main channel of the river and its small tributaries has been made. It has been shown that young salmon in small tributaries feed more intensively. The biomass of the main food objects of juvenile salmon in the tributaries was significantly higher than in the main channel. In small tributaries, thus, feeding conditions are more favorable for the growth of juvenile salmon.