THE IMPACT OF LOW-HEAD DAMS ON FISH SPECIES RICHNESS IN WISCONSIN, USA

Abstract Shannon’s diversity index H’ = pi log2 pi was calculated for 16 fish species. The index was resolved into its components, species richness and relative abundance, to determine which components played a larger role in the determination of diversity pattern. Changes in diversity were correlated with species richness (r), habitat heterogeneity, and hydrological regimes in a longitudinal stretch of 35 km along the river Giri, a major tributary of the Yamuna River system, in Western Himalayas. Abundance differs with change in habitat structures, habitat preference of fish species and water regimes. The decrease in diversity in the lower stretch of about 3-4 km upstream of the barrage was found to be associated with habitat fragmentation and as well as d/s with loss of biotic integrity of aquatic ecosystem due to water scarcity. Species richness was found to be maximum at upper and middle reaches (elevation 650-800 m, msl) of the river, whereas it was low in lower reaches. Change in water chemistry was also noticed at Jatan barrage-low head dam due to impoundment of river water. It is inferred that the regulation of water has an impact on species richness and relative abundance, and on habitat heterogeneity which has decreased due to the change in environmental condition.

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Empirical characterization factors assessing the effects of hydroelectricity on fish richness across three large biomes

10.1101/678383 ◽

2019 ◽

Cited By ~ 1

Author(s):

Katrine Turgeon ◽

Gabrielle Trottier ◽

Christian Turpin ◽

Cécile Bulle ◽

Manuele Margni

Keyword(s):

Species Richness ◽

Fish Species ◽

Statistical Significance ◽

Steady States ◽

Clear Understanding ◽

List Type ◽

Characterization Factors ◽

Alternative Technologies ◽

The Tropics ◽

The Impact

AbstractHydroelectricity is often presented as a clean, reliable, and renewable energy source, but is also recognized for its potential impacts on aquatic ecosystem biodiversity. We used empirical data on change in fish species richness following impoundment to develop Characterisation Factors (CF) and Impact Scores (IS) for hydroelectricity production for use in Life Cycle Assessment (LCA). We used data collected on 89 sampling stations (63 upstream and 26 downstream of a dam) belonging to 27 reservoirs from three biomes (boreal, temperate and tropical). Overall, the impact of hydroelectricity production on fish species richness was significant in the tropics, of smaller amplitude in temperate and minimal in boreal biome, stressing for the need of regionalisation. The impact of hydroelectricity production was also quite consistent across scales (i.e., same directionality and statistical significance across sampling stations, reservoirs and biomes) but was sensitive to the duration of the study (i.e., the period over which data have been collected after impoundment), highlighting the need for a clear understanding of transient situations before reaching steady states. Our CFs and ISs contribute to fill a gap to assist decision makers using LCA to evaluate alternative technologies, such as hydropower, to decarbonize the worldwide economy.HighlightsThis paper is the first to develop global and empirically based characterization factors of the impact of hydroelectricity production on aquatic ecosystems biodiversity, to be used in LCA;The impact of hydroelectricity production on fish species richness was significant in the tropics, of smaller amplitude in temperate and minimal in boreal biome;The impact of hydroelectricity production on fish richness was consistent across scales - same directionality and statistical significance across sampling stations, reservoirs and biomes;The impact of hydroelectricity production on fish richness was sensitive to the duration of the study, highlighting the need for a clear understanding of transient situations before reaching steady states in LCA.

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Linking fish and crustacean taxonomic composition with seasonal contrasts in the soft-bottom intertidal zone

Brazilian Journal of Biology ◽

10.1590/1519-6984.234129 ◽

2020 ◽

Author(s):

M. A. Gondal ◽

S. Iqbal ◽

U. Atique ◽

N. U. Saher ◽

N. A. Qureshi ◽

...

Keyword(s):

Species Richness ◽

Water Temperature ◽

Fish Species ◽

Diversity Index ◽

Taxonomic Composition ◽

Primary Objective ◽

Negative Effect ◽

Fish Species Composition ◽

One Year ◽

Sw Monsoon

Abstract The primary objective of this study was to investigate the seasonal fish and crustacean variations concerning taxonomic composition, species richness, and diversity in sandy beach habitat. For this purpose, we investigated the Sonmiani Hor lagoon area during four distinct seasons, i.e., northeast (NE) monsoon, pre-monsoon, south-west (SW) monsoon, and post-monsoon for one year. During each haul, the net was pulled about 100m along the beach in 0.5m depth. The results showed a strong linear correlation between the diversity index and equitability in fishes (r = 0.978). The diversity index was strong negatively correlated with the abundance and biomass (r = -0.978, -0.972, respectively). The physical attributes like sea surface water temperature and salinity showed a strong negative effect on species assemblages (r = -0.981 and -0.943, respectively). The mean air and water temperature illustrated approximately 3°C difference during NE and pre-monsoon seasons. However, salinity, pH, and electrical conductivity did not show any significant seasonal variabilities. Under the ecological indices, the fish species displayed higher diversity (H’ = 3.19) during SW monsoon, whereas the lowest diversity was observed during pre-monsoon (H’ = 1.58). The equitability and species richness, however, remained more noticeable during SW monsoon (J’ = 0.81). The total number of individuals of fish and crustaceans reached 4799 with 3813 fish individuals and 986 individuals of crustaceans. A total of 27 families of fish while five crustacean families comprising of 30 genera and 38 fish species while ten genera and 17 species of crustaceans were recorded. Liza subviridis displayed the highest abundance among the sampled fish species. In conclusion, fish species constituted a significant part of the coastal fauna in the study area. The seasonal variations displayed distinct variations in fish species composition and diversity.

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Seasonal feeding plasticity can facilitate coexistence of dominant omnivores in Neotropical streams

Reviews in Fish Biology and Fisheries ◽

10.1007/s11160-021-09648-w ◽

2021 ◽

Author(s):

Mayara P. Neves ◽

Pavel Kratina ◽

Rosilene L. Delariva ◽

J. Iwan Jones ◽

Clarice B. Fialho

Keyword(s):

Seasonal Variation ◽

Fish Species ◽

Resource Availability ◽

Seasonal Changes ◽

Dry Season ◽

Diet Overlap ◽

Isotopic Niche ◽

Neotropical Streams ◽

Feeding Plasticity ◽

The Impact

AbstractCoexistence of ecomorphologically similar species in diverse Neotropical ecosystems has been a focus of long-term debate among ecologists and evolutionary biologists. Such coexistence can be promoted by trophic plasticity and seasonal changes in omnivorous feeding. We combined stomach content and stable isotope analyses to determine how seasonal variation in resource availability influences the consumption and assimilation of resources by two syntopic fish species, Psalidodon aff. gymnodontus and P. bifasciatus, in the Lower Iguaçu basin. We also tested the impact of seasonality on trophic niche breadth and diet overlap of these two dominant omnivores. Seasonal changes in resource availability strongly influenced the consumption and assimilation of resources by the two fish species. Both species exhibited high levels of omnivory, characterized by high diversity of allochthonous resources in the wet season. Terrestrial invertebrates were the main component of diet during this season. However, in the dry season, both species reduced their isotopic niches, indicating diet specialization. High diet overlap was observed in both seasons, but the isotopic niche overlap was smaller in the dry season. Substantial reduction in the isotopic niche of P. bifascistus and a shift toward aquatic invertebrates can facilitate coexistence during this season of resource shortage. Feeding plasticity allows omnivorous fish to adjust their trophic niches according to seasonality, promoting the exploitation of different resources during periods of greater resource diversity. This seasonal variation could be an important mechanism that contributes to the resource partitioning and coexistence of dominant omnivores in Neotropical streams.

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Facilitation Effects of Haloxylon salicornicum Shrubs on Associated Understory Annuals, and a Modified “Stress-Gradient” Hypothesis for Droughty Times

Plants ◽

10.3390/plants9121726 ◽

2020 ◽

Vol 9 (12) ◽

pp. 1726

Author(s):

Nasr H. Gomaa ◽

Ahmad K. Hegazy ◽

Arafat Abdel Hamed Abdel Latef

Keyword(s):

Species Richness ◽

Water Availability ◽

Stress Gradient ◽

Growing Season ◽

Annual Species ◽

Negative Effects ◽

Growing Seasons ◽

Dry Seasons ◽

The Impact ◽

Haloxylon Salicornicum

Perennial shrub-annual plant interactions play key roles in desert regions influencing the structure and dynamics of plant communities there. In the present study, carried out in northwestern Saudi Arabia, we examined the effect of Haloxylon salicornicum shrubs on their associated understory annual species across four consecutive growing seasons, along with a record of the seasonal rainfall patterns. We measured density and species richness of all the annual species in permanent quadrats located beneath individual shrubs, as well as in the spaces between shrubs. During wet growing season H. salicornicum shrubs significantly enhanced the density and species richness of sub-canopy species, whereas in the relatively dry seasons they exerted negative effects on the associated species. In all growing seasons, the presence of shrubs was associated with enhanced soil properties, including increased organic carbon content, silt + clay, and levels of nutrients (N, P and K). Shrubs improved soil moisture content beneath their canopies in the wet growing season, while in the dry seasons they had negative effects on water availability. Differences in effects of H. salicornicum on understory plants between growing seasons seem due to the temporal changes in the impact of shrubs on water availability. Our results suggest the facilitative effects of shrubs on sub-canopy annuals in arid ecosystems may switch to negative effects with increasing drought stress. We discuss the study in light of recent refinements of the well-known “stress-gradient hypothesis”.

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Patterns of fish species richness in the Seine River basin, France

Hydrobiologia ◽

10.1007/bf00006595 ◽

1993 ◽

Vol 259 (3) ◽

pp. 157-167 ◽

Cited By ~ 73

Author(s):

Thierry Oberdorff ◽

Eric Guilbert ◽

Jean-Claude Lucchetta

Keyword(s):

Species Richness ◽

River Basin ◽

Fish Species ◽

Seine River ◽

Seine River Basin

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ORIGINAL ARTICLE: Fish species richness decreases with salinity in tropical coastal lagoons

Journal of Biogeography ◽

10.1111/j.1365-2699.2006.01588.x ◽

2006 ◽

Vol 34 (1) ◽

pp. 52-61 ◽

Cited By ~ 46

Author(s):

Atahualpa Sosa-López ◽

David Mouillot ◽

Julia Ramos-Miranda ◽

Domingo Flores-Hernandez ◽

Thang Do Chi

Keyword(s):

Species Richness ◽

Fish Species ◽

Coastal Lagoons

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Sampling efforts for determining fish species richness in megadiverse tropical regions

Environmental Biology of Fishes ◽

10.1007/s10641-021-01184-7 ◽

2021 ◽

Author(s):

Paulo S. Pompeu ◽

Débora R. de Carvalho ◽

Cecília G. Leal ◽

Rafael P. Leitão ◽

Carlos Bernardo M. Alves ◽

...

Keyword(s):

Species Richness ◽

Fish Species ◽

Tropical Regions

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Monitoring of small rock pools reveals differential effects of chronic anthropogenic disturbance on birds and mammals in the Calakmul region, southern Mexico

Journal of Tropical Ecology ◽

10.1017/s0266467421000547 ◽

2021 ◽

pp. 1-10

Author(s):

Carlos M. Delgado-Martínez ◽

Fredy Alvarado ◽

Melanie Kolb ◽

Eduardo Mendoza

Keyword(s):

Species Richness ◽

Anthropogenic Disturbance ◽

Forest Cover ◽

Biosphere Reserve ◽

Bird Diversity ◽

Small Scale ◽

Rock Pools ◽

Southern Mexico ◽

Wildlife Species ◽

The Impact

Abstract Great attention has been drawn to the impacts of habitat deforestation and fragmentation on wildlife species richness. In contrast, much less attention has been paid to assessing the impacts of chronic anthropogenic disturbance on wildlife species composition and behaviour. We focused on natural small rock pools (sartenejas), which concentrate vertebrate activity due to habitat’s water limitation, to assess the impact of chronic anthropogenic disturbance on the species richness, diversity, composition, and behaviour of medium and large-sized birds and mammals in the highly biodiverse forests of Calakmul, southern Mexico. Camera trapping records of fauna using sartenejas within and outside the Calakmul Biosphere Reserve (CBR) showed that there were no effects on species richness, but contrasts emerged when comparing species diversity, composition, and behaviour. These effects differed between birds and mammals and between species: (1) bird diversity was greater outside the CBR, but mammal diversity was greater within and (2) the daily activity patterns of birds differed slightly within and outside the CBR but strongly contrasted in mammals. Our study highlights that even in areas supporting extensive forest cover, small-scale chronic anthropogenic disturbances can have pervasive negative effects on wildlife and that these effects contrast between animal groups.

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