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Relative influence of variables at multiple spatial scales on stream macroinvertebrates in the Northern Lakes and Forest ecoregion, U.S.A. 总被引：4，自引：0，他引：4
Brian M. Weigel Lizhu Wang Paul W. Rasmussen Jason T. Butcher Paul M. Stewart Thomas P. Simon Michael J. Wiley 《Freshwater Biology》2003,48(8):1440-1461
- 1 We used 94 sites within the Northern Lakes and Forests ecoregion spanning Minnesota, Wisconsin and Michigan to identify environmental variables at the catchment, reach and riparian scales that influence stream macroinvertebrates. Redundancy analyses (RDA) found significantly influential variables within each scale and compared their relative importance in structuring macroinvertebrate assemblages.
- 2 Environmental variables included landcover, geology and groundwater delivery estimates at the catchment scale, water chemistry, channel morphology and stream habitat at the reach scale, and landcover influences at three distances perpendicular to the stream at the riparian scale. Macroinvertebrate responses were characterised with 22 assemblage attributes, and the relative abundance and presence/absence of 66 taxa.
- 3 Each scale defined macroinvertebrates along an erosional to depositional gradient. Wisconsin's macroinvertebrate index of biotic integrity, Ephemeroptera–Plecoptera–Trichoptera taxa and erosional taxa corresponded with forest streams, whereas organic pollution tolerant, Chironomidae and depositional taxa corresponded with wetland streams. Reach scale analyses defined the gradient similarly as dissolved oxygen and wide, shallow channels (erosional) opposed instream macrophytes and pool habitats (depositional). Riparian forests within 30 m of the stream coincided with an erosional assemblage and biotic integrity.
- 4 Next, we combined all significant environmental variables across scales to compare the relative influence of each spatial scale on macroinvertebrates. Partial RDA procedures described how much of the explained variance was attributable to each spatial scale and each interrelated scale combination.
- 5 Our results appeared consistent with the concept of hierarchical functioning of scale in which large‐scale variables restrict the potential for macroinvertebrate traits or taxa at smaller spatial scales. Catchment and reach variables were equally influential in defining assemblage attributes, whereas the reach scale was more influential in determining relative abundance and presence/absence.
- 6 Ultimately, comprehending the relative influence of catchment and reach scale properties in structuring stream biota will assist prioritising the scale at which to rehabilitate, manage and derive policies for stream ecosystem integrity.
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- Understanding changes in macroinvertebrate communities is important because they play a large role in stream ecosystem functioning, and they are an important food resource for fish. Beaver-induced changes to stream morphology could alter macroinvertebrate communities, which in turn could affect food webs and ecosystem function. However, studies investigating the effects of North American beaver activities on macroinvertebrates are rare in the inter-mountain west, an area with high potential for beaver-assisted restoration.
- The aim of this study was to quantify differences in the macroinvertebrate community between unaltered segments of streams and within beaver ponds in north-eastern Utah, U.S.A. We assessed macroinvertebrate species richness, biomass, density, functional feeding group composition, mobility group composition, and macroinvertebrate habitat characteristics to test the hypothesis that macroinvertebrate communities will differ among habitat types (undammed stream segments and beaver ponds) in beaver-occupied streams.
- Beaver pond communities significantly differed from lotic reach communities in many ways. Beaver ponds were less diverse with 25% fewer species. Although there was variability among streams, in general, beaver ponds had 75% fewer individuals and 90% lower total macroinvertebrate biomass compared to lotic reaches.
- Regarding functional feeding groups, beaver ponds contained more engulfers, while lotic reaches contained more scrapers, filterers, and gatherers. For mobility groups, beaver ponds had more sprawlers, while lotic reaches had more clingers. Swimmers were also more prevalent in lotic reaches, although this is probably due to the abundance of Baetis within lotic reaches. More beaver pond taxa were classified as lentic-dwelling insects, while more lotic reach taxa were categorised as preferring lotic habitats.
- The creation of ponds by beavers fundamentally altered the macroinvertebrate community in north-eastern Utah streams. Such changes to stream macroinvertebrate communities suggest that recolonisation of beavers across North America may be altering stream functioning and food webs. Our study highlights the need to further investigate the effects of beaver recolonisation on stream communities.
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This study determined the relative influences of environmental variation versus spatial autocorrelation on benthic macroinvertebrate
community composition of temperate headwater streams. We enumerated fauna in riffle zones of 23 separate (i.e., not tributaries
to each other) but closely grouped from first- to third-order woodland streams surrounding Zoar Valley Canyon, western New
York State, USA, during spring, summer, and fall of 2006. Watershed geomorphology (stream order, catchment area, and forest
cover) and semi-quantitative habitat characteristics, the latter of which were incorporated into a Qualitative Habitat Evaluation
Index (QHEI), were also recorded for each stream. Non-metric Multidimensional Scaling (NMDS) ordination was used to establish
patterns of biotic similarity among these streams. Matrices of biological and environmental Euclidean distances were constructed
for all between-stream pairings. Additionally, a between-stream spatial matrix was constructed based on global position system
coordinates of sampling sites. Non-significant partial Mantel coefficients indicated that biological distances were uncorrelated
with spatial distances both among all 23 study streams and among 12 first-order streams only. In contrast, biological distances
were positively correlated with environmental distances (r
M = 0.375 and 0.289 for all streams and for first-order streams only, respectively; P values < 0.05). Environmental and spatial distances were uncorrelated (partial Mantel P values > 0.05), indicating that the measured environmental characteristics were not spatially structured. Each of the geomorphological
and habitat variables was statistically associated with NMDS community composition axes (stepwise multiple regression, one-factor
MANOVA). These results suggest that environmental filters and niche-based species sorting may operate here between separate
streams, and that study sites appear to be effectively insular in their biota despite close physical proximity.
Handling editor: Sonja Stendera 相似文献
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Macroinvertebrate community response to natural and forest harvest gradients in western Oregon headwater streams 总被引：1，自引：0，他引：1
1. To examine the effects of forest harvest practices on headwater stream macroinvertebrates, we compiled a 167 site database with macroinvertebrate, fish, physical habitat and catchment land cover data from the three forested ecoregions in western Oregon. For our analysis, headwater streams were defined by catchment areas <10 km2 and perennial water during summer low flows. Almost all sites in the database were selected using a randomised survey design, constituting a representative sample of headwater streams in these ecoregions. 2. Macroinvertebrate taxonomic and functional feeding group composition were very similar among the three ecoregions in the study area (Coast Range, Cascades and Klamath Mountains). On average, 55% of the individuals at each site were in the orders Ephemeroptera, Plecoptera or Trichoptera. Dipteran taxa (mostly chironomids) accounted for another 34%. At almost all sites, non‐insects made up <10% of the macroinvertebrate assemblage. Almost half (49%) of the assemblages were collectors; remaining individuals were about evenly divided among scrapers, shredders and predators. 3. There were 189 different macroinvertebrate taxa at the 167 sites with richness at individual sites ranging from 7 to 71 taxa. Ordination by non‐metric multidimensional scaling revealed a strong association between % Ephemeroptera, especially Baetis, and site scores along the first axis. This axis was also strongly related to % coarse substratum and fast water habitat. The second axis was strongly related to % intolerant individuals, site slope and altitude. No strong relationships were evident between any ordination axis and either logging activity, presence/absence of fish, catchment size or ecoregion. 4. Based on macroinvertebrate index of biotic integrity (IBI) scores, 62% of the sites had no impairment, 31% of the sites had slight impairment and only 6% of the sites had moderate or severe impairment. IBI scores were not strongly related to forest harvest history. All four severely impaired sites and five of the seven sites with moderate impairment were lower altitude, shallower slope stream reaches located in the Coast Range with evidence of agricultural activity in their catchment or riparian zone. % sand + fine substratum was the environmental variable most strongly related to macroinvertebrate IBI. 相似文献
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Zi&#x;Ao Yuan Xin&#x;xin Liu Hai&#x;rong Du Ming&#x;Hai Zhang 《Ecology and evolution》2021,11(21):14988
- Many policies and studies globally have highlighted the pivotal role of wetland ecosystems regarding wetland biota and their ecological status. With the strengthening of wetland ecosystem management legislation and policy, wetland restoration should also consider increasing habitat diversity to improve biota. We explore whether the construction of artificial ecological islands can increase the diversity of and macroinvertebrates before assessing the effects of actively constructing islands via human intervention on wetland protection.
- We discuss changes in macroinvertebrate diversity (i) with and without islands, (ii) at different water‐level gradients surrounding the islands, (ⅲ) on different island substrates, and (ⅳ) at different time scales. We used ANOVA, ANOSIM, and cluster analysis to test the differences.
- The macroinvertebrate communities had spatially heterogeneous distributions which changes over time due to both natural and anthropogenic stresses. The establishment of islands significantly increased the community composition and biodiversity of the macroinvertebrate. Water depth and substrate affect community composition of macrozoobenthos. The abundance and diversity of macroinvertebrates can influence the biodiversity of their predators (fish and waterbirds). Potentially, the construction of islands could provide some cobenefits for the conservation of wetland fauna.
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Mirela Serti&#x; Peri&#x; Jens M. Nielsen Carsten J. Schubert Christopher T. Robinson 《Freshwater Biology》2021,66(1):114-129
- Glacial retreat, accompanied by shifts in riparian vegetation and glacier meltwater inputs, alters the energy supply and trophic structure of alpine stream food webs. Our goal in this study was to enhance understanding of dietary niches of macroinvertebrates inhabiting different alpine streams with contrasting glacial and non‐glacial (groundwater, precipitation, snowmelt) water inputs in conjunction with seasonal and habitat‐specific variation in basal resource availability.
- We measured a range of stream physico‐chemical attributes as well as carbon and nitrogen isotopes (δ13C, δ15N) of macroinvertebrates and primary food sources at seven sites across seasons within a Swiss glaciated catchment (Val Roseg) undergoing rapid glacial retreat (1–2 km between 1997 and 2014). Sampling sites corresponded to streams used in a previous (1997/1998) study within the same alpine catchment.
- Physico‐chemical attributes showed wide variation in environmental conditions across streams and seasons. Significant correlation among physico‐chemical proxies of glacier meltwater (phosphate‐P, total inorganic carbon, conductivity, turbidity) and macroinvertebrate δ13C, δ15N, and size‐corrected standard ellipse area (a proxy for feeding niche width) values showed that the extent of glacial water input shapes the energy base among alpine streams. Feeding niche differences among common alpine stream insect taxa (Chironomidae, Baetidae, Heptageniidae) were not significant, indicating that these organisms probably are plastic in feeding behaviour, opportunistically relying on food resources available in a particular stream and season.
- Seasonal trends in macroinvertebrate δ13C largely followed patterns in periphyton δ13C values, indicating that autochthonous resources were the main consumer energy source within the stream network, as shown previously. The overall range in macroinvertebrate δ13C (?33.5 to ?18.4‰) and δ15N (?6.9 to 6.7‰) values also corresponded to values measured in the previous study, suggesting that macroinvertebrates altered diets in line with changes in environmental conditions and food resources during a period of rapid glacial retreat. Our results suggest that environmental changes brought on by rapid glacial retreat have not yet caused a profound change in the trophic structure within these fluvial networks.
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Verónica Crespo-Pérez Olivier Dangles Cristina Ibarra Rodrigo Espinosa Patricio Andino Dean Jacobsen Sophie Cauvy-Fraunié 《Freshwater Biology》2020,65(8):1348-1362
- In many mountainous areas, glaciers feed streams characterised by harsh environmental conditions, such as low water temperature, high turbidity, low channel stability, and high temporal variability in flow. Additionally, in many glacierised catchments, the mixture of streams arising from different water sources (glacier melt, groundwater, rainfall) generates high levels of environmental heterogeneity, which enhance species turnover rates and increase regional diversity.
- Studies from mainly temperate regions have revealed some consistent patterns: a predominance of traits adaptive to harsh environmental conditions and reduced functional diversity with increased glaciality, both strongly related to environmental filtering. Here, we investigated variation in functional structure and diversity between macroinvertebrate communities from 15 stream sites, with different water sources (five glacier-fed, five groundwater-fed, and five mixed source) and level of glacier influence, in a glacierised catchment in the Ecuadorian Andes.
- Our results revealed functional differences between communities inhabiting the different stream types. As found in temperate regions, high levels of glaciality were associated with an increase of small-sized taxa that do not swim but are temporarily attached to or burrow in the substrate, have a flying-adult stage, and feed by collecting–gathering. Similarly, we found a general decrease in functional diversity at sites with higher glacier influence. A null modelling approach suggested that in some of our glacier-fed sites, environmental filtering may be the main driver of community assembly, whereas other mechanisms, mainly regional (such as dispersal), but also local (such as intraspecific competition), may gain importance as glacier influence decreases.
- Assemblage composition in streams in tropical glacierised catchments may be driven by both local and regional processes that generate a gradient of decreasing functional diversity with stronger glacier influence. However, lack of knowledge of relevant traits for taxa in tropical glacierised streams currently poses a substantial obstacle to predicting changes likely to arise from global warming and glacier melt in this region.
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Rachel L. Malison Mark S. Lorang Diane C. Whited Jack A. Stanford 《Freshwater Biology》2014,59(6):1229-1246
Our aim was to determine how beavers affect habitats and food resources for juvenile salmon in the Kwethluk River in western Alaska.
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