Benthic Invertebrate Community Structure Research Articles

The effect of oil pollution on community structure of benthic macro ‎invertebrates in the northwest of the Persian Gulf ‎ ‎(Case study: Jafari creek)‎

<p>This study evaluates the contamination levels of heavy metals and petroleum hydrocarbons in Jafari ‎Creek sediments and the effect of these pollutions on Macrobenthos in 2017. Studies to understand ‎the effect of heavy metal Cadmium, Chromium, Nickel, Lead, Selenium, Zinc, Copper, and ‎Vanadium, and 16 hydrocarbon compounds, organic material, and soil texture on the population of ‎Jafari Creek Macrobenthos in five stations along the estuary and analyzed using standard ‎procedures. The 4 identified Macrobenthos included Bivalvia with 9 species, Gastropoda with 8 ‎species, Crustacea with 7 species, and Polychaeta with 6 species totaling Macrobenthos 3645.14 per ‎square meter. The dominant class was Polychaetes (53.9%), followed by Bivalvia (23.2%), ‎Gastropoda (9.93%), and Crustaceans (15.8%), with slightly different (P<0.05), were in the second ‎and third class. Among the studied metals, zinc, chromium, and nickel had the highest ‎concentration. Among the hydrocarbons, Anthracene at station 1, Fluorene at station 2, ‎Phenanthrene and Dibenzo [A, H] Anthracene at station 3, and Fluoranthene at station 4 with a ‎concentration between <0.01- 0.091 ppm had the highest value. The highest and lowest heavy metal ‎concentrations were measured at station 4 (215.54 ± 14.58 ppm) and station 1 (102.39 ± 24.15 ‎ppm), respectively. In return, stations 1 (0.339 ± 0.074 ppm) and 4 (0.196 ± 0.078 ppm) had the ‎highest and lowest concentration of hydrocarbons, respectively. Regarding the number of identified ‎Macrobenthos, stations 3 and 2, with 1738.64 and 333.28 n/m2 had the highest and lowest numbers, ‎respectively. The class of Crustacea had a positive correlation with zinc, copper, and lead metal and ‎a negative correlation with Selenium. Polychaeta was positively correlated with cadmium and ‎vanadium. Gastropoda had a negative correlation with vanadium and chromium, a positive ‎correlation with lead and hydrocarbons, and Bivalvia correlated negatively with lead and zinc and ‎had a correlation with vanadium. Considering that the areas around Jafari Creek are an industrial, ‎petrochemical, and economic region considered one of the important catchments in the province of ‎Khuzestan, the sediments, water, and animal tissues must be periodically the analysis of heavy ‎metals and oil hydrocarbons should be considered.‎</p>

Impacts of dyke systems on the distribution of benthic invertebrate communities and physicochemical characteristics of surface water in An Giang, Vietnam.

The dyke system plays a vital role in cultivating rice intensively in the Vietnamese Mekong Delta, which protects rice paddy fields from annual floods. This study aimed to examine whether the full-dyke system (FD, which restricts water exchange for a long time) can cause degradation of surface water quality and reduction in benthic invertebrate biodiversity. The surface water quality and benthic invertebrate community were compared between the FD and semi-dyke systems (SD, which permits water exchange during flooding season) using a large number of samples collected seasonally in 2019. The results showed that the surface water quality within the FD system had significantly higher concentrations of TSS, COD, BOD5, N-NO3-, N-TKN, P-PO43-, and TP than compared to the SD system (p < 0.05), indicating greater pollution levels. The benthic invertebrate community was less diverse in the FD system than in the SD system. Only 17 species (belonging to 4 families) were detected in the FD system, and 30 species (belonging to 5 families) were detected in the SD system. The benthic invertebrate community structure changes and biodiversity loss were associated with degraded water quality. The P-PO43- and TP parameters were negatively correlated with the number of species, density, and biomass in the FD system and with the Shannon-Wiener (H') index in the SD system. In conclusion, the FD system has been degrading water quality and causing biodiversity loss.

A marine protected area network does not confer community structure resilience to a marine heatwave across coastal ecosystems.

Marine protected areas (MPAs) have gained attention as a conservation tool for enhancing ecosystem resilience to climate change. However, empirical evidence explicitly linking MPAs to enhanced ecological resilience is limited and mixed. To better understand whether MPAs can buffer climate impacts, we tested the resistance and recovery of marine communities to the 2014-2016 Northeast Pacific heatwave in the largest scientifically designed MPA network in the world off the coast of California, United States. The network consists of 124 MPAs (48 no-take state marine reserves, and 76 partial-take or special regulation conservation areas) implemented at different times, with full implementation completed in 2012. We compared fish, benthic invertebrate, and macroalgal community structure inside and outside of 13 no-take MPAs across rocky intertidal, kelp forest, shallow reef, and deep reef nearshore habitats in California's Central Coast region from 2007 to 2020. We also explored whether MPA features, including age, size, depth, proportion rock, historic fishing pressure, habitat diversity and richness, connectivity, and fish biomass response ratios (proxy for ecological performance), conferred climate resilience for kelp forest and rocky intertidal habitats spanning 28 MPAs across the full network. Ecological communities dramatically shifted due to the marine heatwave across all four nearshore habitats, and MPAs did not facilitate habitat-wide resistance or recovery. Only in protected rocky intertidal habitats did community structure significantly resist marine heatwave impacts. Community shifts were associated with a pronounced decline in the relative proportion of cold water species and an increase in warm water species. MPA features did not explain resistance or recovery to the marine heatwave. Collectively, our findings suggest that MPAs have limited ability to mitigate the impacts of marine heatwaves on community structure. Given that mechanisms of resilience to climate perturbations are complex, there is a clear need to expand assessments of ecosystem-wide consequences resulting from acute climate-driven perturbations, and the potential role of regulatory protection in mitigating community structure changes.

Experimental warming and browning influence autumnal pelagic and benthic invertebrate biomass and community structure

Abstract Globally, lakes are warming and browning with ongoing climate change. These changes significantly impact a lake's biogeochemical properties and all organisms, including invertebrate consumers. The effects of these changes are essential to understand, especially during critical periods after and before the growing season, that is, autumn and spring, which can determine the composition of the invertebrate consumer community. In this study, we used a large‐scale experimental pond system to test the combined effect of warming (+3°C) and increased input of terrestrial and coloured dissolved organic carbon (gradient of 1.6–8.8 mg/L in the ambient and 1.6–9.3 mg/L in the warm)—which causes browning—on zooplankton and benthic macroinvertebrate biomass and composition during the autumn and the following spring. Total zooplankton biomass decreased with warming and increased with browning, while total zoobenthos did not respond to either treatment. Warming and browning throughout the autumn had no overall interactive effects on zooplankton or zoobenthos. Autumnal warming decreased total pelagic consumer biomass, caused by a decrease in both Rotifera and Copepoda. In contrast, there was no effect on overall benthic consumer biomass, with only Asellus sp. biomass showing a negative response to warming. An autumnal increase in dissolved organic carbon led to increased total pelagic consumer biomass, which was related to increases in Daphnia sp. biomass but did not affect zoobenthos biomass. While we expected zooplankton and zoobenthos biomass to follow responses in primary and bacterial production to treatments, we did not find any relationship between consumer groups and these estimates of resource production. Our results suggest that consumer responses to warming and browning during autumn may lead to less overarching general changes in consumer biomass, and responses are mostly taxon‐specific. This study gives novel insights into the effects of warming and browning on consumer biomass during autumn and spring and increases the understanding of the effects of climate change on invertebrate community biomass in the different habitats.

How herbivores reshape a macroalgal community on a Little Cayman coral reef: The role of herbivore type and density

Many coral reefs throughout the world continue to decline in health and resilience. In the Caribbean, much of this decline has been attributed to increases in algal cover due to the loss of herbivores such as herbivorous fishes, especially large parrotfish, and the sea urchin Diadema antillarum. In recent years, the combination of protections and natural recovery has helped these herbivores, particularly parrotfishes, to recover in some areas. This recovery has led to questions about how different herbivores affect both the overall benthic cover of macroalgae and the specific composition of algal communities. Toward that end, we designed a caging experiment in Little Cayman to manipulate density and type of grazers. Treatments included full cages (1.27 cm wire mesh) with 4 D. antillarum/m2 added, full cages with 1 D. antillarum/m2, lidless cages (fences) open to herbivorous fishes without D. antillarum, full cages (herbivore exclosures) that excluded most fishes and urchins and open cageless controls. Benthic cover was quantified to assess differences in percent cover and community structure of macroalgae and benthic invertebrates throughout the 5-month study. As the experiment proceeded, both percent algal cover and algal community structure in the full herbivore exclosures, treatments open to fishes (open plots and fences), and treatments with D. antillarum (both densities) diverged. No changes were observed in percent cover of corals or other benthic invertebrates. Overall, reductions in percent algal cover were greater in the high density (4/m2) D. antillarum treatment compared to the low density (1/m2) D. antillarum treatment or those treatments where fishes were allowed access. As expected, greater densities of sea urchins reduced algal cover more quickly. However, these high density treatments also affected the D. antillarum themselves. The condition of the urchins (assessed as ratio of mass to test diameter) at the conclusion of the experiment declined in the 4 D. antillarum/m2 treatment compared to urchins in the 1 D. antillarum/m2 treatment and natural populations. Moreover, high densities of D. antillarum were better able to reduce the abundance of the brown macroalgae Lobophora spp. and Dictyota spp. compared to natural assemblages of herbivorous fishes. These findings suggest that these different types of herbivores, i.e., fishes and D. antillarum, exert different pressures on available algae. Their relative abundances will likely dictate macroalgal community structure on Caribbean coral reefs, and thus the suitability of a reef for the settlement of vital sessile organisms, especially corals.

Effects of arborescent octocoral assemblages on the understory benthic communities of shallow Caribbean reefs

Since about 2000, octocorals on the shallow reefs of St. John, US Virgin Islands, have increased in abundance to form dense stands analogous to terrestrial forests. In this study, the ecology of octocoral forests was explored by testing for an effect of their canopies on the light regime and benthic invertebrate community in the understory habitat. Octocoral forests at five sites (7–13 m depth) were quantified on a spatial scale of meters by the height and density of octocoral colonies. Their effects on the understory habitat were evaluated through measurements of downwelling light, benthic invertebrate community structure, and the photophysiology (i.e., induction time) of the common coral, Porites astreoides (Lamarck, 1816). Octocoral forests composed of dense (> 5 octocorals m−2) and tall (mean height of 42 cm) octocoral colonies created an understory habitat characterized by flashes of bright light (i.e., sunflecking). Within the understory habitat at two of three study sites, the community structure of benthic invertebrates was modified by the octocoral canopy, but it remained unaffected at a third site. A test for the effects of sunflecking on the induction time of P. astreoides found no difference between colonies in the understory versus the open reef habitat. These results do not support the notion that the physiological phenotype of autotrophs in the understory habitat is modified to exploit sunflecking. The analysis of the benthic invertebrates in the understory habitat suggests that octocoral forests can change the community structure of this group of organisms, relative to the open reef. The causes of this change are unclear, but its absence at the most sheltered study site suggests that water motion may be a contributing factor. The strong likelihood that octocoral forests mediate ecologically significant changes in the community structure of invertebrates within their understory habitat warrants further investigation.

Combining eDNA and morphological approaches to reveal the impacts of long-term discharges of shale gas wastewaters on receiving waters

The potential threats of shale gas wastewater discharges to receiving waters is of great concern. In this study, chemical analyses and biomonitoring were performed three times in a small river that received treated wastewater over a two-year period. The results of chemical analyses showed that the concentrations of chloride, conductivity, barium, and strontium increased at the discharge site, but their concentrations decreased considerably farther downstream (≥500 m). The concentrations of toxic organic compounds (16 US EPA priority polycyclic aromatic hydrocarbons and 6 priority phthalates), trace metals (strontium, arsenic, zinc, copper, chromium, lead, cadmium, nickel, and neodymium), and natural radionuclides (40K, 238U, 226Ra, and 232Th) were comparable to the corresponding background values or did not exhibit obvious accumulation in sediments with continued discharge. Morphological and environmental DNA approaches were used to reveal the potential effects of wastewater discharges on aquatic ecosystems. The results showed that the community structure of benthic invertebrates was not altered by the long-term discharges of shale gas wastewaters. However, the biodiversity indices (richness and Shannon) from the two approaches showed inconsistencies, which were caused by multiple reasons, and that substrates had a strong influence on the morphological biodiversity indices. A multimetric index was proposed to further analyze morphological and environmental DNA data, and the results showed no significant difference between the upstream and downstream sites. Generally, the chemical and biological results both demonstrated that the discharges of shale gas wastewaters had limited impacts on river ecosystems within two years.

Community structure of marine benthic invertebrates recruited on artificial substrates in the Korean coast

Community structure of marine benthic invertebrates recruited on artificial substrates in the Korean coast

Structural factors driving benthic invertebrate community structure on historical shipwrecks in a large North Atlantic marine sanctuary

Shipwrecks are irreplaceable historical resources and valuable biological habitats. Understanding the environmental and anthropogenic factors affecting shipwrecks is critical for preservation in situ. We used remotely operated vehicles to study the benthic invertebrate communities on four shipwrecks in Stellwagen Bank National Marine Sanctuary (SBNMS, North Atlantic, USA). Shipwrecks included coal schooners and a passenger steamer, all >100 years old. These large, complex structures hosted dense populations of invertebrates (34 species), especially on high-relief and overhanging substrata. Some species that are otherwise rare in the community may proliferate through asexual reproduction and form dense populations on shipwrecks. We also investigated impacts of entangled fishing gear on the invertebrate communities on each shipwreck and found that areas with the most ghost gear have lower species richness and different community structure. Fishing, particularly bottom trawling, damages shipwrecks and poses a threat to these valuable cultural resources and biological habitats in SBNMS.

Восстановление макрозообентоса после дноуглубительных работ на озере Манжерокском (Республика Алтай)

Dredging is the activity of excavating soil and performing other soil operations in order to expand and increase the depth of water bodies. Under conditions of increased pollution, dredging operations may cause certain damage to aquatic ecosystems in general and to particular aquatic species. The changes in the composition and structure of benthic invertebrate communities have been studied in Lake Manzherokskoe in different periods: before dredging (2007), two weeks after the dredging has been started (2018), and 3 years after the dredging activities have been finished (2021). In 2021, there was an increase in species diversity and quantitative indicators of the development of benthic communities comparing to the period of dredging completion. Our data indicated the restoration of macrozoobenthos community in the lake to a certain extent. Later, this process may end in complete restoring with an increase in the water level in the lake and a significant decrease in the technogenic load on bottom communities.

Community structure of benthic invertebrates in the Allipén River basin, North Patagonia, Araucania region (38º S, Chile).

One of the biological indicators most used to determine the health of a fluvial ecosystem are the benthic macroinvertebrates. The presence of recurrent species in a wide gradient of latitudes, dominates the biogeographic pattern of the benthic macroinvertebrates in Chilean fresh waters, nevertheless the knowledge on the communitarian ecology of these in the Chilean rivers continues to be scarce. Null models became a powerful statistical tool for describing the ecological mechanisms that drive the structure of an ecological community and the underlying patterns of diversity. The objective of this study was to determine the community structure of benthic invertebrates in the Allipén River by describing their composition, richness and abundance of species through richness models and null models based on presence/absence. The results reveal a high family richness and low diversity, three phyla, five classes, 11 orders and 28 families were identified in the study area during the four seasons of the year. The Arthropoda phylum was the most representative in abundance and richness. Regarding to richness, Trichoptera (7 families) and Diptera (6 families) followed by Ephemeroptera (3 families) were the orders that showed the greatest diversity of families, however, a low diversity with a H'≤ 1.5 nit was registered in the study area. We demonstrated through the null models, the randomization in the species associations corresponding to the three analyzed sites. The information provided here contributes to the understanding of the ecological patterns of the invertebrate communities in the Allipén River, establishing the basis for more complex ecological studies.

The fauna of aquatic invertebrates in the river impacted by wastewaters from the pulp and paper industry (Komi Republic).

BackgroundInvertebrates are important elements of aquatic ecosystems and play a crucial role in the transformation of matter and energy in continental water bodies. Communities of aquatic invertebrates are characterised by high sensitivity to pollution by nutrients and toxic substances and acidification of water bodies; they serve as good bioindicators of the quality of the aquatic environment and impacts on hydroecosystems. All hydrobionts participate in the processes of self-purification of water bodies.The presented dataset provides information on the aquatic invertebrate community of a large northern river. During 2018-2020, we collected data on changes in the quantitative indicators of the development of benthic and planktonic communities, as well as the species diversity of their fauna. The dataset combines information about the occurrence and abundance of benthic and planktonic invertebrates and summarises data of aquatic invertebrate species found in the Vychegda River in the zone of influence from the pulp and paper mill.New informationThe presented dataset is part of a monitoring programme of the river ecosystems in the production area of Mondi Syktyvkar JSC (the European North-East of Russia, Komi Republic). The dataset describes the structure of benthic invertebrate and plankton communities in the Northern Dvina River Basin. The data on the finding and abundance of large taxa of aquatic invertebrates and species of some groups: Oligochaeta, Cladocera, Copepoda, Rotifera, Ephemeroptera, Plecoptera and Trichoptera are presented. In total, the resource includes 8720 findings of invertebrates, of which 6041 are for zoobenthos organisms and 2679 for zooplankton organisms.

Freshwater Releases Into Estuarine Wetlands Change the Determinants of Benthic Invertebrate Metacommunity Structure

In recent years, the relative importance of the processes driving metacommunity composition has aroused extensive attention and become a powerful approach to identify community patterns and their regulatory mechanisms. We investigated variations in the composition of benthic community in restored wetlands and natural wetlands in the Yellow River Delta (Shandong Province, China). First, spatial structures within each wetland were modeled with Moran eigenvector maps. Next, the variation in community structure among local environmental and spatial variables was partitioned using constrained ordination, and the “elements of metacommunity structure” analysis was used to determine the patterns of best fit for species distributions within metacommunities. Finally, the null model was used to analyze non-random patterns of species co-occurrence. The community structure of benthic invertebrates in restored wetlands and natural wetlands differed significantly. The benthic invertebrate metacommunity structure showed a nested distribution in restored wetlands and a quasi-Clementsian structure in natural wetlands. Pure environmental fractions and pure spatial fractions were critical in regulating benthic invertebrate metacommunities of restored wetlands. In natural wetlands, pure spatial fractions and the interaction between environmental and spatial factors (shared fractions) played a major role in the metacommunity. A species co-occurrence analysis showed that species co-occurred more frequently than expected by chance, demonstrating that biotic interactions were not the main driver of metacommunity structures in both wetland types. Accordingly, the benthic invertebrate metacommunity in estuarine wetlands following freshwater releases was mostly determined by environmental and spatial effects, which resulted in a metacommunity with nested distribution. These results are important for biodiversity protection and ecosystem management of estuarine wetlands in the Yellow River Delta.

Surface oil is the primary driver of macroinvertebrate impacts following spills of diluted bitumen in freshwater

The response of freshwater invertebrates following accidental releases of oil is not well understood. This knowledge gap is more substantial for unconventional oils such as diluted bitumen (dilbit). We evaluated the effects of dilbit on insect emergence and benthic invertebrates by conducting experimental spills in limnocorrals (10-m diameter; ~100-m3) deployed in a boreal lake at the IISD-Experimental Lakes Area, Canada. The study included seven dilbit treatments (spill volumes ranged from 1.5 L [1:66,000, oil:water, v/v] to 180 L [1:590, oil:water, v/v]), two controls, and additional lake reference sites, monitored for 11 weeks. Invertebrate emergence declined at the community level following oil addition in a significantly volume-dependent manner, and by 93–100 % over the 11 weeks following the spill in the highest treatment. Dilbit altered community structure of benthic invertebrates, but not abundance. One-year post-spill and following oil removal using traditional skimming and absorption techniques, benthic richness and abundance were greater among all treatments than the previous year. These results indicate that recovery in community composition is possible following oil removal from a lake ecosystem. Research is needed concerning the mechanisms by which surface oil directly affect adult invertebrates, whether through limiting oviposition, limiting emergence, or both. The response of benthic communities to sediment tar mats is also warranted.

Assisted colonization of a regionally native predator impacts benthic invertebrates in fishless mountain lakes

AbstractThe intentional introduction of native cold‐water trout into high‐elevation fishless lakes has been considered a tool to build resilience to climate change (i.e., assisted colonization); however, ecological impacts on recipient communities are understudied. The purpose of this study was to inform native cold‐water trout recovery managers by assessing potential consequences of translocating a regionally native trout (westslope cutthroat trout; Oncorhynchus clarkii lewisi) into fishless mountain lakes. This study compared littoral benthic invertebrate richness, diversity, community structure and abundance between three groups of lakes (fishless, native trout, nonnative trout) in the Canadian Rocky Mountains. While richness and diversity were preserved across all lake groups, other lines of evidence suggested that the introduction of native westslope cutthroat trout into fishless lakes can alter littoral benthic invertebrate communities in similar ways as nonnative brook trout (Salvelinus fontinalis). The community structure of cutthroat trout lakes resembled brook trout lakes compared to that of fishless lakes. For example, both trout‐lake groups contained a lower density of free‐swimming ameletid mayflies and a higher density of certain burrowing taxa. Risk assessments for trout‐recovery actions should consider the potential for collateral damage to recipient invertebrate communities. Future research should identify possible cascading trophic effects on species subsidized by invertebrate prey.

Hydraulic calculation of fish ladders, Sebesel River, Romania

Sebesel 1 hydropower development is located on the Sebesel River, in the outskirts of Borlova, Caraş-Severin County. The realization of the fish ladder will not influence the flow regime of the surface or groundwater in the neighboring area. The fish ladder is dimensioned so as to allow the migration of the ichthyofauna upstream during the spawning period and the partial transit of the alluviums as well as the downstream provision of a servitude flow Q = 0.059 mc / s. The Sebeşel 1 hydroelectric power plant is a hydropower arrangement by shunt without accumulation lake. The plant has two power groups equipped with Pelton turbines. The power delivered by MHC Sebesel 1 is 876.03 kW. The installed flow rate is 0.90 m3 / s; gross fall: 131 m; capture rate 814 mdMN. The fish ladders are of the technical ladder type with pools. The objectives of the studies were: to describe the qualitative and quantitative structure of benthic invertebrate and fish macro communities; assessment of the ecological status of the rivers in the areas of hydropower development; highlighting the presence of fish species of conservative interest and assessing the status of their populations. The methodology was carried out in accordance with the provisions of the Water Framework Directive, Annex V used took into account the following: Assessment of the status of aquatic communities; description of the structure of fish communities; assessment of the ecological status of the river sectors. The study led to obtaining some essential information for the exploitation and maintenance of the micro-hydroelectric plant as well as the fish ladder.

Variability in benthic invertebrate community structure near warm water effluents of a power plant in the southern Caspian Sea

Anthropogenic changes to the temperature regime of a water body, including but not limited to climate change and thermal pollution, may influence the community structure of species living therein. Among these, benthic communities, due to their limited movement and long life span, are one of the best biological indicators to reflect the impact of environmental stressors. In this regard, the thermal pollution of Pare-Sar power plant in the southern Caspian Sea was used as a natural laboratory to assess the effects of warming on macrobenthic communities’ biomass, abundance, richness, and structure throughout the year. Water temperature near the effluents of the power plant was on average 1.29 °C higher than the control sites. We observed that warming led to an increase in the abundance and species richness of benthic macroinvertebrates. However, benthos biomass was significantly lower in the impact site rather than the control sites, probably due to the increased proportion of small-bodied taxa and decreased growth rate of biomass determinant taxa. Therefore, our findings may be an indication of potential benthic community response to thermal pollution and may provide a baseline for future projections under global climate change scenarios.

&lt;p class="HeadingRunIn"&gt;&lt;strong&gt;Long-term macrobenthic community structure changes in the Upper Sakarya River System (1995–2015)&lt;/strong&gt;&lt;/p&gt;

The Upper Sakarya River System (USRS) is one of the most important river systems in Turkey. Its primary drainage is provided by the Porsuk Seydi and Bardakçı Rivers and their tributaries. Long term benthic invertebrate community structure in the USRS was investigated from 1995–2015 (with sampling conducted every five years) in order to assess changes in their composition and in relation to water quality. Oligochaete specimens sorted from samples were identified to the species level when possible; all other invertebrate specimens sorted from samples were identified to order and family level. In addition, some environmental parameters (e.g., dissolved oxygen, temperature, and hydrogen ion concentration as pH) were measured in situ. Although Ephemeroptera-Plecoptera-Trichoptera fauna were the most abundant group in fauna of USRS during the years 1995, 2000 and (in part) 2005 (18.80, 17.69, and 14.07%, respectively), this ratio decreased to 7.90% during the more recent years of monitoring. In 1995, 2000 and 2005, Nais bretscheri, Chaetogaster diastrophus, Chaetogaster langi, Pristinella jenkinae, Aulodrilus pigueti, Aulodrilus pluriseta, Potamothrix hammoniensis, and Psammoryctides albicola were the dominant oligochaete taxa. After 2005, tubificine species became more prevalent in samples. While 6 stations had high BMWP (Biological Monitoring Working Party) value in 1995, 2000 and 2005, only 1 station had high value after 2005. Values of Shannon Diversity Indices ranged from 2.00 to 3.05 for the years 1995–2000, 1.87 to 2.24 for the years 2000–2005, 1.06 to 1.85 for the years 2005–2010, and 0.97 to 1.80 for the years 2010–2015. In USRS, while values of dissolved oxygen were measured as 8.00 mg/l and 9.00 mg/l in 1995 and 2000, this high value was measured only at one station in 2015. It was found that numerical and proportional distributions of benthic invertebrates in the USRS have changed considerably between 1995 and 2015. It is obvious that these changes are the result of anthropogenic habitat degradation.

黄河三角洲芦苇湿地底栖无脊椎动物与环境因子的关系研究——以石油开采区与淡水补给区为例

PDF HTML阅读 XML下载 导出引用 引用提醒 黄河三角洲芦苇湿地底栖无脊椎动物与环境因子的关系研究——以石油开采区与淡水补给区为例 DOI: 10.5846/stxb201901100087 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家重点研发计划项目（2017YFC0505901）；国家青年科学基金项目（41801084）；吉林省科技发展计划项目（20180101080JC）；中国博士后科学基金项目（194419） Composition of benthic invertebrate communities in reed (Phragmites australis) wetlands of the Yellow River Delta: Comparisons between oil exploitation and freshwater recharge areas Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:分别于2018年5月和8月对黄河三角洲芦苇湿地19（淡水补给区11处，石油开采区8处）处采样点的底栖无脊椎动物和水体理化指标进行调查采样，运用统计方法分析两个区域物种组成、优势种、多样性、群落结构以及与环境因子的关系。结果表明：两季共采集到底栖无脊椎动物54种，主要以水生昆虫、腹足纲和软甲纲为主，淡水补给区和石油开采区各类群组成差异明显。独立样本T检验表明淡水补给区和石油开采区水体理化指标间差异显著（P<0.05）。双因子方差分析显示，昆虫纲和腹足纲密度在两区域差异显著（P<0.05），软甲纲和腹足纲密度在季节上差异明显（P<0.05）。底栖无脊椎动物优势种共10种，淡水补给区指示物种8种，而石油开采区未发现有指示物种。聚类和非参数多维排序（nMDS）显示，底栖无脊椎动物群落结构相似性较低；RDA结果表明：淡水补给区底栖无脊椎动物群落结构主要受Cond，TDS，Sal，pH，Eh，HCO3-，SO42-等环境因子的影响。石油开采区底栖无脊椎动物群落结构影响较大的环境因子为HCO3-、NH4-N。 Abstract:The benthic invertebrates and environmental factors were sampled and analyzed in May and August, 2018 from 19 sites of reed wetlands (11 freshwater recharge areas and 8 oil exploitation areas) in the Yellow River Delta. Multivariate analysis methods were used to analyze the composition, dominant species, biodiversity, community of benthic invertebrate assemblages, as well as their relationships to the environmental factors. The results showed that 54 taxa collected by two samplings were mainly composed by Aquatic Insect, Gastropoda and Mollusca. There are obvious differences in composition of benthic invertebrates between freshwater recharge and oil exploitation area. Independent-Samples T Test showed that freshwater recharge area and oil exploitation area were significant different in environmental factors (P<0.05). Two-way ANOVA analysis showed that there were significant differences in insect and Gastropoda density between the two regions (P<0.05). The seasonal variations of Mollusca density and Gastropoda density were both significant (P<0.05). Ten species of benthic invertebrates were dominant in the study area. Eight species of benthic invertebrate were tested to be the indicator species in freshwater recharge area, but no indicator species were found in oil exploitation area. Cluster and nMDS analysis indicated the low similarity of the benthic invertebrate community between the freshwater recharge area and oil exploitation area. The RDA results showed that the community structure of benthic invertebrates in freshwater recharge area was mainly affected by Cond, TDS, Sal, pH, Eh, HCO3-, SO42- and the influential environmental factor in oil exploitation areas were HCO3-and NH4-N. 参考文献 相似文献 引证文献

The impacts of hydraulic clamming in shallow water and the importance of incorporating anthropogenic disturbances into habitat assessments

Hydraulic dredging for shellfish is known to create some of the highest levels of disturbance, affecting the benthic microfaunal community and the physical characteristics of the substrate. Properly conducted benthic habitat assessments are complex and time consuming, resulting in assessments not being conducted increasing the uncertainty in post impact studies. Hydraulic dredging for Atlantic surfclams (Spisula soldidissima) took place at Herring Cove, Massachusetts in the winter of 2014–2015 resulting in areas of high impact disturbance of the seafloor. Surveys conducted in the summer of 2015 included hydroacoustics, benthic invertebrate sampling, video, and grain size analysis for the creation of a habitat map of Herring Cove. The four habitats (A–D) identified were a mix of sand, shell, cobble, algae, and eelgrass. Habitat type “D” is a mix of sand, algae and cobble material and occurred at 12 of 18 stations. These 12 stations were distributed across areas of “high” (n = 4), “low” (n = 2), and “no” (n = 6) hydraulic dredge disturbance. Once habitat was accounted for, benthic invertebrate community structure varied significantly (Analysis of similarity; significance level of sample statistic: 0.3%) between areas of “high”, “low” to “no” disturbance. Areas of “low” to “no” dredge track coverage contained high abundances of bivalves, echinoderms, and isopods, whereas highly disturbed areas had highest abundances of polychaetes and oligochaetes. Future mapping efforts, especially surveys with biological components, need to include and quantify the level, type and spatial distribution of anthropogenic alterations. More attention should be given to “reference maps” instead of “baseline maps”. The latter of which omits to acknowledge pre-existing anthropogenic disturbances and has the potential to skew monitoring of restoration and management efforts.