The relative importance of natural and anthropogenic effects on community composition of aquatic macrophytes in Mediterranean ponds

2011 ◽  
Vol 62 (2) ◽  
pp. 101 ◽  
Author(s):  
Rocío del Pozo ◽  
Camino Fernández-Aláez ◽  
Margarita Fernández-Aláez
Keyword(s):  
Community Composition ◽  
Submerged Macrophytes ◽  
Anthropogenic Impacts ◽  
Natural Habitat ◽  
Ecological Status ◽  
Variance Partitioning ◽  
Anthropogenic Effects ◽  
Relative Importance ◽  
Study Support ◽  
Variation Explained

To detect when changes in response to stressors are occurring, biomonitoring programs require an understanding of shifts in biota that occur in response to anthropogenic and natural effects. Aquatic plants are expected to reflect the environmental conditions of ponds and, according to the European Water Framework Directive, macrophytes should be considered in ecological status assessments of inland surface waters. We assessed the relative importance of natural and anthropogenic impacts on submerged, emergent and floating-leaved macrophytes in 44 ponds in Duero river basin (North Iberian Plateau). Constrained canonical ordinations included 15 taxa of submerged macrophytes and 24 species of emergent and floating-leaved macrophytes. Although the proportion of variation explained by all selected variables was relatively low (37%), we found that submerged community composition reflected the influence of natural (habitat and biotic variables) and anthropogenic effects. However, emergent and floating-leaved macrophytes were not influenced by biotic variables. Variance partitioning showed that degradation category was the best predictor of both submerged macrophytes and emergent and floating-leaved macrophyte composition. However, submerged macrophytes were more affected by chemical variables, whereas emergent and floating-leaved macrophyte composition was best explained by land-use variables. The results of this study support the use of macrophyte communities as effective indicators of the ecological status of Mediterranean ponds.

scholarly journals Monitoring Skeletal Anomalies in Big-Scale Sand Smelt, Atherina boyeri, as a Potential Complementary Tool for Early Detection of Effects of Anthropic Pressure in Coastal Lagoons

Water ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 159
Author(s):  
Chiara Leone ◽  
Francesca De Luca ◽  
Eleonora Ciccotti ◽  
Arianna Martini ◽  
Clara Boglione
Keyword(s):  
Early Detection ◽  
Habitat Degradation ◽  
Anthropogenic Impacts ◽  
Coastal Lagoons ◽  
Ecological Status ◽  
Detection Methods ◽  
Anthropogenic Pressures ◽  
Morphological Examination ◽  
Skeletal Anomalies

Mediterranean coastal lagoons are increasingly affected by several threats, all concurrently leading to habitat degradation and loss. Methods based on fish for the assessment of the ecological status are under implementation for the Water Framework Directive requirements, to assess the overall quality of coastal lagoons. Complementary tools based on the use of single fish species as biological indicators could be useful as early detection methods of anthropogenic impacts. The analysis of skeletal anomalies in the big-scale sand smelt, Atherina boyeri, from nine Mediterranean coastal lagoons in Italy was carried out. Along with the morphological examination of fish, the environmental status of the nine lagoons was evaluated using a method based on expert judgement, by selecting and quantifying several environmental descriptors of direct and indirect human pressures acting on lagoon ecosystems. The average individual anomaly load and the frequency of individuals with severe anomalies allow to discriminate big-scale sand smelt samples on the basis of the site and of its quality status. Furthermore, a relationship between skeletal anomalies and the environmental quality of specific lagoons, driven by the anthropogenic pressures acting on them, was found. These findings support the potentiality of skeletal anomalies monitoring in big-scale sand smelt as a tool for early detection of anthropogenic impacts in coastal lagoons of the Mediterranean region.

scholarly journals Assembly processes of gastropod community change with horizontal and vertical zonation in ancient Lake Ohrid: a metacommunity speciation perspective

2016 ◽  
Vol 13 (10) ◽  
pp. 2901-2911 ◽  
Author(s):  
Torsten Hauffe ◽  
Christian Albrecht ◽  
Thomas Wilke
Keyword(s):  
Community Composition ◽  
Community Assembly ◽  
Environmental Filtering ◽  
Dispersal Limitation ◽  
Species Interaction ◽  
Relative Importance ◽  
Lake Depth ◽  
Ancient Lake ◽  
Lake Ohrid ◽  
Speciation Model

Abstract. The Balkan Lake Ohrid is the oldest and most diverse freshwater lacustrine system in Europe. However, it remains unclear whether species community composition, as well as the diversification of its endemic taxa, is mainly driven by dispersal limitation, environmental filtering, or species interaction. This calls for a holistic perspective involving both evolutionary processes and ecological dynamics, as provided by the unifying framework of the “metacommunity speciation model”.The current study used the species-rich model taxon Gastropoda to assess how extant communities in Lake Ohrid are structured by performing process-based metacommunity analyses. Specifically, the study aimed (1) to identifying the relative importance of the three community assembly processes and (2) to test whether the importance of these individual processes changes gradually with lake depth or discontinuously with eco-zone shifts.Based on automated eco-zone detection and process-specific simulation steps, we demonstrated that dispersal limitation had the strongest influence on gastropod community composition. However, it was not the exclusive assembly process, but acted together with the other two processes – environmental filtering and species interaction. The relative importance of the community assembly processes varied both with lake depth and eco-zones, though the processes were better predicted by the latter.This suggests that environmental characteristics have a pronounced effect on shaping gastropod communities via assembly processes. Moreover, the study corroborated the high importance of dispersal limitation for both maintaining species richness in Lake Ohrid (through its impact on community composition) and generating endemic biodiversity (via its influence on diversification processes). However, according to the metacommunity speciation model, the inferred importance of environmental filtering and biotic interaction also suggests a small but significant influence of ecological speciation. These findings contribute to the main goal of the Scientific Collaboration on Past Speciation Conditions in Lake Ohrid (SCOPSCO) deep drilling initiative – inferring the drivers of biotic evolution – and might provide an integrative perspective on biological and limnological dynamics in ancient Lake Ohrid.

scholarly journals Using trait data improves correlation between environment and community data only if abundances are considered

2021 ◽  
Author(s):  
Attila Lengyel ◽  
Sándor Barabás ◽  
Boglárka Berki ◽  
Anikó Csecserits ◽  
Adrienn Gyalus ◽  
...  
Keyword(s):  
Explanatory Power ◽  
Seed Mass ◽  
Analysis Data ◽  
Variance Partitioning ◽  
Procrustes Analysis ◽  
Geographical Distance ◽  
Spatial Variables ◽  
Environmental Matching ◽  
Variation Explained ◽  
Analysis Models

AbstractA straightforward way to explore variation between communities is to calculate dissimilarity indices and relate them with environmental and spatial variables. Communities are most often represented by the (relative) abundances of taxa they comprise; however, more recently, the distribution of traits of organisms included in the communities has been shown more strongly related to ecosystem properties. In this study, we test whether taxon- or trait-based dissimilarity is correlated more tightly with environmental difference and geographical distance and how the abundance scale influences this correlation. Our study system is grassland vegetation in Hungary, where we sampled vegetation plots spanning a long productivity gradient from open dry grasslands to marshes in three sites. We considered three traits for vascular plants: canopy height, specific leaf area and seed mass. We obtained field estimates of normalized vegetation difference index (NDVI) as proxy of productivity (water availability) for each plot. We calculated between-community dissimilarities using a taxon-based and a trait-based index, using raw and square-root transformed abundances and presence/absence data. We fitted distance-based redundancy analysis models with NDVI difference and geographical distance on the dissimilarity matrices and evaluated them using variance partitioning. Then, using the pooled data, we calculated non-metric multidimensional scaling ordinations (NMDS) from all types of dissimilarity matrices and made pairwise comparisons using Procrustes analysis. Data analysis was done separately for the three sites.We found that taxonomical dissimilarity matches environmental and spatial variables better when presence/absence data is used instead of abundance. This pattern was mainly determined by the increasing variation explained by space at the presence/absence scale. In contrast to this trend, with trait-based dissimilarity, accounting for abundance increased explained variation significantly due to the higher explanatory power of NDVI. With abundance data, considering traits improved environmental matching to a great extent in comparison with taxonomical information. However, with presence/absence data, traits brought no advantage over taxon-based dissimilarity in any respect. Changing the abundance scale caused larger difference between ordinations in the case of trait-based dissimilarity than with taxonomical dissimilarity.We conclude that considering relevant traits improves environmental matching only if abundances are also accounted for.Supporting informationAdditional graphs supporting the results are presented as appendix.Open researchData used in this research are publicly available from Dryad ###link to be supplied upon acceptance###

scholarly journals Heterogeneity and Anthropogenic Impacts on a Small Lowland Stream

Water ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 2002
Author(s):  
Somlyai ◽  
Berta ◽  
Nagy ◽  
Dévai ◽  
Ács ◽  
...  
Keyword(s):  
Agricultural Land ◽  
Human Impacts ◽  
Anthropogenic Impacts ◽  
Anthropogenic Effects ◽  
Nitrogen And Phosphorus ◽  
Buffer Zones ◽  
Small Surface ◽  
Great Heterogeneity ◽  
Physical And Chemical Variables ◽  
Physical And Chemical

During our work, we investigated the physical and chemical variables of a small surface watercourse to investigate how different anthropogenic effects affect its water quality. Along this small watercourse, there are well-separated areas that are affected by various anthropogenic effects. In addition to its origin and branches, in many places it is surrounded by agricultural land with insufficient buffer zones, which burdens the small watercourse with nitrogen and phosphorus forms. In the lower stages, artificial damming inhibits the natural flow of the Tócó Canal, thereby creating eutrophicated stagnant water areas. This is further strengthened by, in many cases, illegal communal and used water intake that further burdens the small watercourse. Considering the experience of our investigation, it can be stated that the examined small watercourse could barely suffer human impacts, and it could be described with great heterogeneity using physical and chemical variables. We experienced that this heterogeneity caused by anthropogenic effects appeared in all hydrologic states and seasons. Furthermore, our research showed that these small watercourses had such high heterogeneity that their monitoring and examination should be taken just as seriously as when it comes to larger watercourses.

scholarly journals Bio-Ecological Traits of Western Tubenose Goby Proterorhinus semilunaris (Heckel, 1837): A Key to Understand Its Invasion Success

Water ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1247 ◽  
Author(s):  
Gülşah Saç
Keyword(s):  
Standard Length ◽  
Natural Habitat ◽  
Invasion Success ◽  
Biological Traits ◽  
Relative Importance ◽  
Ecological Traits ◽  
Tubenose Goby ◽  
Significant Difference ◽  
Index Of Relative Importance ◽  
Proterorhinus Semilunaris

This study aims to contribute to the limited knowledge on the bio-ecological traits of the native Western tubenose goby, Proterorhinus semilunaris, which is considered to invade many inland waters in Europe and North America. During monthly sampling surveys from March 2012 to June 2013, the species was collected from the four stations in the Istranca River (Turkey) by electrofishing. The standard length and body weight of 310 samples varied between 1.4–6.1 cm and 0.08–7.09 g, respectively. The sex ratio of female to male was found to be 1.7:1.0, with a significant difference. The values of the exponent b in the length–weight relationship were approximately 3 for females, males, and all individuals, indicating an isometric growth. The size at first sexual maturity was 2.44 cm standard length (SL) for females and 2.29 cm SL for males. Absolute fecundity ranged from 56 to 344 eggs with a mean of 164 eggs. The food composition of the species comprised of 8 major groups: Insecta (Diptera, Ephemeroptera, Plecoptera, Odonata, Trichoptera, Coleoptera), Arachnida, Annelida, Gastropoda, Crustacea, Pisces, plant, and detritus. According to the results of modified index of relative importance (MI) and index of relative importance (IRI), insect and Diptera were the most prevalent prey for this fish. The present study has provided baseline information on the basic biological traits of the fish in its natural habitat for further understanding of this species success of invasion.

scholarly journals Protection alone may not promote natural recovery of biogenic habitats of high biodiversity damaged by mobile fishing gears

2018 ◽  
Author(s):  
Jose M. Fariñas-Franco ◽  
A. Louise Allcock ◽  
Dai Roberts
Keyword(s):  
Habitat Restoration ◽  
Anthropogenic Impacts ◽  
Natural Habitat ◽  
Management Strategies ◽  
Keystone Species ◽  
Marine Bivalve ◽  
Natural Recovery ◽  
Protection Measures ◽  
Fishing Gears ◽  
Horse Mussel

The horse mussel Modiolus modiolus (L.) is a large marine bivalve that aggregates to create complex habitats of high biodiversity. As a keystone species, M. modiolus is of great importance for the functioning of marine benthic ecosystems, forming biogenic habitats used to designate Marine Protected Areas (MPAs). The present study investigates the condition of M. modiolus beds historically subjected to intense scallop fishing using mobile fishing gears. The study, conducted seven years after the introduction of legislation banning all forms of fishing, aimed to establish whether natural habitat recovery occurs after protection measures are put in place. Lower biodiversity and up to 80% decline in densities of M. modiolus were recorded across the current dis- tributional range of the species in Strangford Lough, Northern Ireland. The decline in biodiversity in most areas surveyed was consistent with that observed in biogenic reefs impacted by mobile fishing gears elsewhere. Epifauna, including sponges, hydroids and tunicates, experienced the most substantial decline in biodiversity, with up to 64% fewer taxa recorded in 2010 compared with 2003. Higher variability in community composition and a shift towards faunal assemblages dominated by opportunistic infaunal species typical of softer substrata were also detected. Based on these observations we suggest that, for biogenic habitats, the designation of MPAs and the introduction of fishing bans alone may not be sufficient to reverse or halt the negative effects caused by past anthropogenic impacts. Direct intervention, including habitat restoration based on translocation of native keystone species, should be considered as part of management strategies for MPAs which host similar biogenic reef habitats where condition and natural recovery have been compromised.

scholarly journals Ecological status assessment of the Samokovska river: 2018 case study

2021 ◽  
pp. 167-181
Author(s):  
Snežana Simić ◽  
Aleksandra Mitrović ◽  
Nevena Đorđević ◽  
Sanja Radosavljević
Keyword(s):  
Environmental Protection Agency ◽  
Anthropogenic Impacts ◽  
Monitoring Program ◽  
Ecological Status ◽  
Diatom Indices ◽  
Physico Chemical ◽  
Quality Aspects ◽  
Ecological Status Assessment ◽  
Status Assessment

The Samokovska River, as the most important watercourse of the Kopaonik National Park, has been poorly investigated from algological and water quality aspects. This river is not covered by the monitoring program of the Serbian Environmental Protection Agency routine. Our research performed in October 2018 aimed to present an algal diversity, ecological status assessment, and negative anthropogenic impacts threatening this river. For ecological status assessment purposes, the diatom indices phytobenthos and physico-chemical parameters of water were used. The typology and the problem of reliable assessing of the ecological status were also discussed on the example of the Samokovska River.

scholarly journals An attempt to assess the ecological status of a lake based on historical and current maps of submerged vegetation

2017 ◽  
Vol 25 (1) ◽  
pp. 33-42
Author(s):  
Andrzej Hutorowicz ◽  
Marcin Białowąs ◽  
Bronisław Długoszewski ◽  
Lech Doroszczyk
Keyword(s):  
Aquatic Vegetation ◽  
Submerged Macrophytes ◽  
Ecological Status ◽  
Maximum Depth ◽  
Current Status ◽  
Ecological State ◽  
Stratified Lakes ◽  
Analogous Data ◽  
The Status ◽  
Macrophyte Index

Abstract The possibility of doing a back assessment of the ecological status of a lake based on archival bathymetric maps indicating areas overgrown with rushes and aquatic vegetation was verified. This assessment was assumed to be in accordance with that performed with the official Polish macrophyte-based method for lake assessment (Ecological State Macrophyte Index, ESMI). The study was conducted on Lake Dobrąg located in the Warmian-Masurian Voivodeship (surface area - 108 ha, maximum depth - 27.9 m, mean depth - 11.6 m). It included the hydroacoustic distribution of submerged macrophytes along 85 evenly distributed belt transects (perpendicularl to the shore line), creating a bathymetric chart and maps of vegetation occurrence and identifying areas occupied by hydrophytes (Cmax) and the maximum depth of lake colonization (Z). Analogous data were read from archival bathymetric chart dating from 1964-1968. The values obtained were compared with the means (and their confidence intervals) of 83 stratified lakes in Poland in different ecological status classes. Analysis of changes indicated that the ecological status of the lake had deteriorated. In the mid-1960s, the status of the lake was less than “very good” while the current status borders between “good” and “moderate.” The results indicate that the proposed method could be useful when attempting to assess changes in ecological status using archival bathymetric charts showing areas overgrown with vegetation and the distribution of it in lakes.

Sign in / Sign up

Export Citation Format

Share Document