Ecological Health Assessment Research Articles

Development of a multi-metric index based on macroinvertebrates for wetland ecosystem health assessment in predominantly agricultural landscapes, Upper Blue Nile basin, northwestern Ethiopia

Developing multi-metric indices (MMIs) as a tool for inland water ecosystem assessment has attracted the attention of the global scientific community. The number of studies, which developed macroinvertebrate-based multi-metric indices for wetlands, however, was very limited. Thus, more work is needed to refine and implement it depending on the ecological contexts of wetlands. On top of this, we developed multi-metric indices based on macroinvertebrate assemblages that could be used for the ecological health assessment of wetlands that are impacted by agricultural activities in North-western Ethiopia. About 20 sampling sites were established in four wetlands along the disturbance gradient to take water and macroinvertebrates samples. The reference sites, which were least disturbed by human intervention, were established for the construction of multi-metric indices. Six core metrics were selected for the development of the final multi-metric indices from fifty-six potential metrics of macroinvertebrate assemblages after passing through sensitivity and statistical tests. The findings demonstrated all reference sites had good or high ecological conditions. On the contrary, the ecological statuses of nearly 70% of the impaired sites were found to be in bad to poor conditions. A significant distinction between reference and impaired sites suggested our index ability to identify the gradient variation in the ecological condition of wetlands. A strong negative relationship of the multi-metric indices model with most of the physicochemical variables and all human disturbance factors also suggested the appropriateness of the developed index in informing the ecological status of wetlands. Thus, we believe that our multi-metric indices could be a useful biomonitoring tool for the assessment and monitoring of wetland ecological conditions in predominantly agricultural landscapes in the Upper Blue Nile basin and beyond.

Assessment of Aquatic Ecological Health Based on the Characteristics of the Fish Community Structures of the Hun River Basin, Northeastern China

Long-term ecological restoration can restore aquatic ecosystems to a certain extent and alleviate the crisis of freshwater fish biodiversity. In order to explore the fish community distribution patterns and key factors after ecological restoration and the health status of the watershed, fish and environmental data were collected from 39 sampling points in the Hun River Basin in the spring and autumn of 2021. A total of 51 fish species belonging to 11 families and 37 genera were collected during the survey, and the dominant species were Rhynchocypris lagowskii, Zacco platypus, Carassius auratus and Pseudorasbora parva. Compared with the results of past studies, the number of fish species has increased. The study found that the distribution of fish along the longitudinal gradient of the watershed showed obvious spatial differences and was divided into two groups. The results of canonical correspondence analysis (CCA) showed that agricultural land, urban land and grassland were the key factors for the spatial variation in fish communities in the Hun River Basin. The results of the F-IBI evaluation showed that the health status of the Hun River was fair or above fair, among which healthy, good, fair, poor and bad points accounted for 5.13%, 30.77%, 33.33%, 25.64% and 5.13%, respectively. The upper and middle reaches of the Hun River Basin were in better health, while the lower reaches were in poorer health, which was mainly affected by the intensity of human activities in different regions. This study will help watershed managers to make targeted restoration and protection measures for different regions.

Assessment of ecosystem health based on landscape pattern in ecologically fragile regions at different spatial scales: A case study of Dianchi Lake basin, China

In the process of urbanization, maintaining ecosystem health in ecologically fragile regions is an inevitable requirement for sustainable development in the future, but the ecological health status varies greatly at different spatial scales. Determining the appropriate spatial scale of ecological health assessment is the basis and premise of ecological management and environmental protection policy making. Taking Dianchi Lake basin as the research area, based on the vigor-organization-resilience (VOR) model and landscape pattern index, this study established an assessment system of ecological health to evaluate the ecosystem health status from quadrat, ecological and administrative scales, with the aim to determine a reasonable evaluation scale and strengthen regional sustainability. The results show that: 1) The suitable spatial grain of landscape pattern analysis in Dianchi Lake basin is 150 m. 2) The average values of ecosystem health indices at quadrat scale, ecological scale and administrative scale are 0.5466, 0.4977 and 0.5373, respectively, demonstrating a sub-health state. 3) The most suitable scale for ecological health assessment of Dianchi Lake basin is ecological scale, because taking sub-watershed as ecological unit can ensure the integrity of the evaluated ecosystem to the greatest extent. Multiscale assessment is helpful for eco-environmental management departments to understand the ecosystem health status at different scales and provide a scientific basis for regional eco-environmental management decisions.

Pollution Status, Source Apportionment, Ecological and Human Health Risks of Potentially (Eco)toxic Element-Laden Dusts from Urban Roads, Highways and Pedestrian Bridges in Uganda

The occurrence of potentially (eco)toxic elements (PTEs) in street, indoor and roadside dusts have been associated with potential human health risks. For the first time, the pollution levels of PTEs—copper (Cu), nickel (Ni), manganese (Mn), zinc (Zn), lead (Pb), cadmium (Cd) and chromium (Cr)—were investigated in 24 dust samples from eight selected sampling sites on urban roads, highways and pedestrian bridges constructed over River Manafwa, a flood-prone river in Eastern Uganda. Concentration of PTEs in the sample digests were quantified by atomic absorption spectrometry. Multivariate geostatistical (Pearson’s Correlation, Principal Components and Hierarchical Cluster) analyses were used to apportion sources of the contaminants. Contamination, ecological and human health assessment indices and models were employed to establish any potential risks the elements could pose to the environment and humans. The study revealed that there is severe PTE pollution of dusts from roads, highways and pedestrian bridges in Eastern Uganda when compared with their crustal averages, except for Cu, Ni and Cr. The mean concentrations (mg kg−1) of Cu (11.4–23.2), Ni (0.20–23.20), Mn (465.0–2630.0), Zn (26.8–199.0), Pb (185.0–244.0), Cd (0.178–1.994) and Cr (5.40–56.60) were highest in samples obtained near high-traffic areas. Source apportionment studies suggested that Cu, Ni, Mn and Cr are from combustion processes and vehicular traffic, whereas Pb, Zn and Cd came from traffic and geogenic contributions. Assessment using the pollution load index indicated that only dust from Zikoye–Bushika road, the junction of Zikoye–Bushika and Bududa–Manafwa roads and Manafwa town were substantially polluted as the indices were greater than 1. Further assessment of pollution degree of the dust samples using index of geo-accumulation revealed that the dusts were practically uncontaminated to medium-to-strongly contaminated. Health risk assessment showed that there are non-carcinogenic health risks that could emanate from direct ingestion of PTEs in dusts by children. This study therefore opens the lead for investigation of the contamination levels and the health risks of PTEs in dusts from industrial areas as well as busy Ugandan cities such as Kampala, Jinja, Mbarara and Gulu.

Ecological Health Assessment with the Combination Weight Method for the River Reach after the Retirement and Renovation of Small Hydropower Stations

This study aimed to effectively evaluate the ecological restoration of the river reach where a small hydropower station was retired or renovated. An ecological health index system was constructed based on the environmental characteristics of the upstream and downstream of the small hydropower station after its retirement and renovation. Based on the combination weighting concept of game theory, the combination weights were obtained by the comprehensive analytic hierarchy process (subjective weight) and entropy method (objective weight). This ecological health assessment with fuzzy comprehensive evaluation was applied to assess the health status of Shimen (dam removal) and Changqiao (renovation in ecological flow) reaches of the Tufang River in Changting County, China. The results showed that the ecological health assessment index system proposed in this study was comprehensive and reasonable, and the revision degree of the hydropower station obviously influenced the process of ecological river restoration. The findings from this study would benefit for the rational utilization of water resources and the river ecological health maintenance in mountainous areas.

Spatial and Temporal Heterogeneity and Ecological Health Evaluation of Diatom Community Based on eDNA

In recent years, environmental DNA (eDNA) has been widely used in aquatic biodiversity monitoring, and how to establish a river ecological health assessment method based on eDNA has become a hot topic. This study was intended to develop a molecular diatom index based on eDNA to indicate the ecological health status of rivers under the influence of human activities. Firstly, the diatom community composition and structural changes in the Shaying River basin in spring and autumn were monitored through eDNA, and the driving environmental factors of the diatom community were diagnosed. Further, four strategies (OTU-taxonomy, OTU-free, ASV-taxonomy, and ASV-free) based on eDNA metabarcoding data were compared, and a molecular diatom index suitable for ecological health assessment in the Shaying River basin was constructed. The results showed that: ① there were seasonal differences in diatom community structure, and Discostella pseudostelligera, Nitzschia amphibia, Diatoma vulgaris, and other groups were the main factors to distinguish the seasonal differences. ② Mn, Fe, and TN were the main environmental factors affecting diatom community structure in spring, whereas COD and Cu were the main environmental factors affecting diatom community structure in autumn. ③ Among the four strategies, the diatom index calculated based on OTU-free data better reflected the environmental gradient change; the diatom index showed that the ecological health status of the Shaying River Basin was better in autumn than that in spring in time and better in the upstream than that in the downstream in space. In conclusion, this study monitored diatom community in Shaying River in spring and autumn through eDNA and constructed the molecular diatom index in the Shaying River basin, which promoted the application of eDNA to evaluate river ecological health.

Ecological health assessment using Macroinvertebrate - based Index of Biotic Integrity (M-IBI): Case study Lake Gunung Putri, West Java, Indonesia

Macroinvertebrate Index of Biotic Integrity (M-IBI) is one of the most widely used to assess the health of the aquatic ecosystem. However, few studies of M-IBI on the lake ecosystem. Lake Gunung Putri, which is one of the small lakes in Bogor Regency, West Java affected anthropogenic activities. We collected macroinvertebrates with an Ekman Grab sampler at five different sampling sites of Lake Gunung Putri in February – April 2019. Metric variability, sensitivity, redundancy, and responsiveness to environmental gradients were tested on 22 candidate metrics of properties of richness, taxonomic composition, tolerance, and functional feeding. The selected metrics were the number of taxa, Shannon-Wiener diversity index, percentage of dominant taxa, and Biological Monitoring Working Party (BMWP). Application of M-IBI in the Lake Gunung Putri ranged between 20 to 4 with represented criteria of good, fair, poor, and very poor condition.

Assessment of aquatic ecological health: A comparative study between cistern-made and ‘Natural’ earthen-made waterbody

Ecological health of two waterbodies i.e., cistern-made and ‘natural’ earthen-made waterbody was compared in the present study based on temporal variations of physicochemical and biological parameters. Number of physicochemical parameters [transparency, temperature, pH, electrical conductivity (EC), total dissolved solids (TDS), total suspended solids (TSS), dissolved oxygen (DO), total hardness (TH), total alkalinity (TA), biochemical oxygen demands (BOD), nitrate, phosphate and chlorophyll a (Chl a)], and biological parameters, e.g., zooplankton community and aquatic macrophytes were studied seasonally. Zooplankton communitiy comprised six arthropods and two rotifers. SIMPER analysis depicted that Moina sp., Daphnia sp., and Cyclops sp. were dominant species in cistern pond while Cyclops sp., Daphnia sp., Keratella sp. and Brachionus sp. were dominant in earthen natural pond. Abundance of species was highest in summer followed by post-rainy and winter in both the ponds while maximum abundance of zooplankton was recorded in summer. Species richness peaked in winter in natural pond, while in cistern pond species richness and diversity raised in summer. Multivariate analyses depicted significant temporal variation in zooplankton species in both the conditions. RELATE analysis revealed that temporal variation in species distribution and zooplankton community was significantly correlated with environmental parameters. Moreover, biological-environmental best matching (BIO-ENV) analyses indicated that water temperature, pH, TH and BOD (for cistern pond) and water temperature, EC and TSS (for earthen natural pond) were the main driving forces for temporal variations in species distribution and zooplankton community. Additionally, correlation analysis depicted that Moina sp., Daphnia sp., Diaptomus sp., Cyclops sp., Cypris sp., Bosmina sp., and species abundance was positively (significant) correlated with transparency, water temperature, and Chl a in natural pond. On the other hand, correlation analysis depicted that zooplankton species, species abundance, evenness and diversity were positively correlated with water temperature, DO, BOD and Chl a in cistern pond. Moreover, abundance of aquatic macrophytes were limited in three basic groups, namely free floating [(Lemna sp. (Major), Lemna sp. (Minor), Azolla sp., Pistia sp. and Eichhornia sp.], rooted submerged [Hydrilla sp., Ceratophyllum sp.] and rooted emerged [Nymphaes sp. and Ipomoea sp.]. Further, trophic state index (TSI) value revealed that both the ponds are hyper-eutrophic (‘natural’ waterbody > cistern waterbody) with a strong temporal variations. Therefore, these data could be used as water quality community-based bio-assessment tool as well as basis of water quality management plans to monitor the pollution level or conservation of aquatic ecology.

Ecological integrity of a medium‐sized river of a lake basin towards ecosystem health management

AbstractThis study demonstrates the use of a multi‐metric Fish Index of Biotic Integrity (FIBI) for assessment of ecological health of a medium‐sized river, under a gradient of human disturbances in the Kenyan side of the Lake Victoria Basin (LVB). Development of the index is based on water quality, river habitat quality and fish community attributes. The river was sampled from 2019 to 2020 during wet and dry seasons of the year at nine selected sites along its length based on the level of human disturbance. A total of nine metrics representing the structural and functional organization of fish communities were qualified using the separation power of Mann–Whitney U test (p < .05). Metric values at unimpaired, intermediate, impaired and no‐fish sites were used to establish the scoring criteria using inter‐quartile ranges. A 1, 3, 5 scoring system representing high, fair and slight deviation from the best site, respectively, was used in the final FIBI development. River mouth station had the highest FIBI score of 43, with extensive natural riparian buffer vegetation (>20 m) and 18 fish species implying least human disturbance. The midstream section had intermediate FIBI scores of 34–36, with wide natural riparian buffer vegetation (10–20 m) and 6–9 fish species that represented moderate human disturbance. The upstream section had the least FIBI score of 0, with no fish and narrow riparian buffer vegetation (<5 m) that indicated notable degradation. This study presents the preliminary results of using fish and habitat metrics for development of an Index of Biotic Integrity (IBI) for a medium‐sized river in a lake basin, as a decision‐making support tool for effective management and conservation of water resources. The study recommends restoration of river habitat quality for improved ecological integrity of rivers in the Lake Victoria Basin.

Construction of wetland ecosystem model framework in Phoenix Mountain National Forest Park Nature Reserve in Harbin and application case studies

Context The wetland ecosystem of Harbin Fenghuangshan National Forest Park Nature Reserve is fragile. Aims To establish a scientific and reasonable model framework for dynamic monitoring and ecological health assessment of wetlands, which is conducive to early warning, protection and management of wetland ecosystems. Methods On the basis of the full consideration of energy flow, material circulation, ecological environment and interspecific relationship, this paper proposed an ecosystem model framework. The pressure–state–response (PSR) model was used to build the evaluation index system of wetland-ecosystem health in Harbin Fenghuangshan National Forest Park. The data of each indicator are extracted and standardised through the analytic hierarchy process. Key results The results showed that the ecosystem pressure index of Harbin Fenghuangshan National Forest Park wetland was 0.52, indicating that it is in a subhealth state. The degree of health was 0.603, indicating a good condition. The comprehensive response index was 0.615, which was a positive response. The comprehensive degree of health was 0.577, indicating a subhealth state. Conclusion and implications The management and protection of wetland ecosystem in Harbin Fenghuangshan National Forest Park need to be strengthened urgently.

Functional Trait Analysis and the Multi-metric Integrity Model, Based on Stream Fish Indicators, and Their Relations to Chemical Water Quality

Functional trait and biological integrity approaches in stream ecology enable the determination and prediction of aquatic community responses to a variety of environmental stressors, such as chemical pollution, habitat disturbance, and biological invasion. Here, we used multi-trait based functional groups (FGs) to predict the functional responses of fish assemblages to the physicochemical and ecological health gradients in a temperate stream. The multi-metric biological integrity model (mIBI model) was used to evaluate stream ecological health. The FGs were derived from the distance matrix of trophic, tolerance, and physical habitat traits among fish species. The leading water quality indicators (conductivity [EC], total suspended solids [TSS], and chlorophyll-a [CHL-a]) varied conspicuously with the stream gradient and anthropogenic pollution. The multi-metric water-pollution index (mWPI) showed differences in chemical health from upstream to downstream. Monsoon precipitation may have affected the variations in fish species and associated changes linked to irregular chemical health. The fish FGs varied more by space (longitudinal) than by season (premonsoon and postmonsoon). Functional metrics, which reflected trophic and tolerance traits, as well as vertical position preference, were strongly correlated with water quality degradation downstream. Changes were evident in FG (II, III, and IV) combinations from the upstream to downstream reaches. Furthermore, the structure of the fish assemblages from FG-II and FG-III was significantly correlated with chemical (R2 = 0.43 and 0.35, p < 0.001) and ecological health (R2 = 0.69 and 0.66, p < 0.001), as well as the metrics of mWPI. In conclusion, the results indicate significant variations in both trait-based FGs and biological integrity among stream-fish communities, influenced by chemical water quality gradients. The causes included longitudinal zones and intensifying degradation of water quality downstream. Therefore, multi-trait based FGs can facilitate ecological health assessment and develop the mIBI model based on fish assemblages by reflecting the prevailing chemical health status of streams and rivers.

Preliminary biological data of Sahel wetland ecosystems in Burkina Faso: Implications for ecological health assessment

Birds, amphibians, fish, and macroinvertebrates are useful indicators of ecological conditions and ensure considerable conservation value and tools for decision making in management of wetland ecosystems. However, the use of these organisms to monitor wetland ecosystems has rarely been explored in Western Africa. Whereas, we are currently facing to growing multiple anthropogenic pressures and climate warming that impact negatively our wetlands and the biodiversity. Notably, there is an urgent need of cost-effective tools for wetland ecosystems health assessment in Burkina Faso. In this study, we examined the taxonomic composition of birds, amphibians, fish, and macroinvertebrates and explored their potential use for monitoring wetland ecosystems. From our findings, measures of taxa composition and diversity respond to the gradients of anthropogenic alterations. Our results revealed that the highest diversity of fish and macroinvertebrates taxa was recorded in protected sites, whereas the lowest diversity was obtained in degraded sites. Additionally, the findings showed a strong and positive correlation between macroinvertebrates taxa and key water variables, whereas fish taxa were strongly correlated to xylal (deadwood) substrates. Most of bird’s species were recorded in tree-shrubs, and amphibians of protected wetlands were distinguished by identifying indicator taxa through indicator value index. African wetland ecosystems and biodiversity may be sustainably preserved through responsive monitoring programs of wetlands by limnologists.

Ecological environment health assessment of lake water ecosystem system based on simulated annealing-projection pursuit: A case study of plateau lake

• A DPSR framework model was proposed and covers 26 multi-scale indexes. • Ecosystem health assessment was built from environment, ecology and socioeconomic system. • Ecological health, environmental pollution and water resources were combined to system. • Simulated annealing projection pursuit was introduced as assessment method. • The key factors affecting the Ecological environment health were identified. A lake ecological environment health assessment index system is constructed based on DPSR (Driving forces-Pressure-State-Responses) framework. The simulated annealing projection pursuit (SA-PP) algorithm, which can analyze high-dimensional data, is introduced and provides a new way for lake ecological environment health evaluation and decision-making. Qionghai, a typical plateau lake in Sichuan, China, is taken as an example to introduce the application of this assessment system. The results suggest the water ecological environment of Qionghai basin is in a relatively healthy state from 2017 to 2020. The state subsystem has the largest weight, and the important influencing factors affecting the health of lake water ecological environment are the water environment characteristics, ecological characteristics and pressure subsystem in the State subsystem. Zooplankton Simpson diversity index, chlorophyll a, NH 3 -N and total nitrogen are the main influencing factors of lake ecosystem health in the lake ecosystem health system. The restriction factor of the pressure subsystem is per capita daily domestic water consumption. Therefore, improving water quality and controlling water consumption intensity become important factors to improve the health of water resources and water environment in Qionghai basin. This study provides a new way for lake ecological environment health evaluation and decision-making.

Lake ecological evaluation and land use planning in lakeside area from the perspective of two-way interaction

The healthy development of the lakeside area needs a detailed assessment of lake ecology and land use, and to adopt a targeted dynamic maintenance strategy. This paper is based on the micro perspective. On the one hand, through the subdivision of land use types in lakeside area, the paper discusses the impact of non-point source (NPS) pollution from different types of land on lake ecology. On the other hand, the paper studies the impact of water environmental capacity and water ecological health assessment on lakeside area construction. From a two-way perspective, we can unify the two as a whole, and jointly promote the healthy development of the lakeside area. Studies have shown that the construction of lakeside area needs to control scale and land use types to meet the needs of water ecological protection. The 2-levels, 5-categories, and 17-subcategories of the lake ecological health assessment index can provide effective support for dynamic monitoring and optimization and adjustment of planning strategies. Lakeside area developing is a dynamic and gradual process. The paper provides a feasible method to realize lake ecological protection and urban development.

Combining functional diversity of lotic fish communities with river health assessment based on multi-metric chemical pollution and biological integrity index models

Trait-based functional studies are widely used to elucidate the relationships between ecological indicators and environmental parameters as well as to predict functional change in aquatic biota in response to various types of human disturbance. Clarifying how functional traits of aquatic organisms depend on environmental conditions can facilitate aquatic conservation and management, but determining the importance of these traits to ecological river health requires further investigation. As fish play a key role in the assessment of ecological conditions, we examined the relevance of the functional diversity of lotic fish to the river health assessment using multi-metric models of water pollution (mWPI) and fish-based biological integrity (mIBI). Twelve fish traits related to food acquisition, environmental stability, and mobility were used for the functional analyses. Chemical river health was highly sensitive to downstream organic matter and nutrient pollution according to mWPI. Based on the present gradient of chemical health and water chemical variables, we identified three water quality groups (G-I, G-II, and G-III). G-I, G-II, and G-III showed low, intermediate, and high levels of water quality degradation, respectively. Spatially significant differences among these groups were observed for both the taxonomic and functional structures of lotic fish as well as ecological river health based on mIBI. The dominance of sensitive species was high in G-I, whereas tolerant and exotic species contributed strongly to the species compositions of G-II and G-III. Functional richness and dispersal were significantly reduced in G-III, and their decreases correlated with ecological health and the loss of species that are insectivorous, rheophilic, and sensitive to water pollution. Regarding redundancy analyses, both the models of functional trait metrics (F = 8.06, p &amp;lt; 0.001) and mIBI metrics (F = 4.88, p &amp;lt; 0.01) indicated good performance in terms of the variation in water quality and chemical river health parameters. Overall, the functional trait-based diversity of lotic fish is significant to the assessment of ecological river health and reflects water chemical quality. This association arises because niche occupation in functional space by all species, along with their abundance distribution, is highly responsive to the loss of species with sensitive traits due to water pollution.

Ecological health assessment of two tropical lakes of Bhopal, Madhya Pradesh, India

ABSTRACT This study examines two tropical lakes (known as Upper Lake and Lower Lake) situated in the western side of the capital city of Bhopal, of Madhya Pradesh. The study assesses the two lakes’ ecological health and trophic status, based on water chemistry and insect fauna, as aquatic insects are highly significant indicators of water quality. A total of 44 insect species were recorded from both lakes within this study. Among all the insect fauna, species belonging to orders Odonata and Hemiptera were recorded as the most dominant in both lakes. Physicochemical and biological results for both lakes show high trophic conditions on account of anthropogenic pressure. The water chemistry of Bhopal Lower Lake reveals a degrading condition in comparison to Upper Lake, which has a relatively stable condition.

Phytoplankton community variation and ecological health assessment for impounded lakes along the eastern route of China's South-to-North Water Diversion Project.

Interbasin water diversion projects have been proven to effectively alleviate water resource shortages in areas along water diversion lines, but few studies have focused on ecological health in impounded lakes compared with research on water quality and pollutants. Herein, monitoring data were collected during the nonwater diversion period (NWDP) and the water diversion period (WDP) from 2018 to 2019, and the index of biological integrity (IBI) method based on phytoplankton communities was used to evaluate the ecological health of the impounded lakes (Nansi Lake and Dongping Lake) along the eastern route of the South-to-North Water Diversion Project. The results demonstrated that water diversion improved the water quality of the impounded lakes during the WDP, especially total nitrogen and ammonia nitrogen. Meanwhile, the water diversion affected the phytoplankton community structure and diversity, and network analysis further revealed water diversion could be beneficial to the ecological health of impounded lakes. Furthermore, the P-IBI showed that the overall ecological health assessment was "good" during the WDP. Water diversion substantially improved the ecological health status and stability of the impounded lakes during the dry season. Finally, the direct correlations between the water quality parameters and the P-IBI were weak, and water quality parameters could indirectly affect the P-IBI by changing the phytoplankton community structure. These findings will enhance our understanding of the ecological health of the impounded lakes of the South-to-North Water Diversion Project. Furthermore, this study will provide a reference to support the ecosystem security of impounded lakes in other large water diversion projects.

Ecological health assessment of Ethiopian wetlands: Review and synthesis

Assessment and monitoring of wetlands' ecology is vital to evaluate their ecological conditions, and provide information to support management decisions. Cognizant of this fact, wetland ecological assessment has been an important research agenda. As elsewhere in the world, wetland ecological assessment has been conducted in Ethiopia. This review aims to assess the spatial coverage of wetland ecological studies, the types of assessment tools employed for ecological assessment, the existing status of wetlands' ecologies and the drivers of wetland ecological decline. The review shows that not more than 30 ecological assessment studies have been conducted and published in reputable scientific journals. These studies mainly focused on only three river and lake basins and not more than 40 wetlands. This suggested wetlands’ ecological assessment has gotten scant research attention in the country. Physicochemical indicators have widely been employed to assess the ecological status of wetlands. Even though biological organisms are better indicators, biological approaches have been less applied in Ethiopia to assess the ecological status of wetlands. Therefore, there is an urgent need to monitor and assess Ethiopian wetlands by developing and adopting wetland assessment tools mainly using biological indicators.

Ecological Health Assessment of the Surface Sediments of the Coral Reefs of Khark and Kharko Islands (Persian Gulf, Iran)

Ecological Health Assessment of the Surface Sediments of the Coral Reefs of Khark and Kharko Islands (Persian Gulf, Iran)

Diversity and distribution of fish in the Qilian Mountain Basin.

The Qilian Mountain Basin, on the north-eastern edge of the Qinghai-Tibet Plateau (QTP), supports a high diversity of native and endemic fish. However, the detailed species inventory and distribution patterns concerning fish in the whole Basin remain unknown, which hinders the conservation of biodiversity and assessment of ecological health. We compiled a comprehensive species richness and distribution database of freshwater fish in the Qilian Mountain Basin, based on field investigations and exhaustive data collection from 50 rivers or lakes. Then, we elucidated a distribution pattern using clustering and ordination analyses based on a βdissim matrix with species presence/absence data. A total of 79 freshwater fish species within eight orders, 17 families and 42 genera were recorded. The Qilian Mountain Basin could be grouped into six systems, which match the six Basins (i.e. Heihe River Basin, HHR; Qaidam Basin, QDM; Qinghai Lake Basin, QHL; Shule River Basin, SLR; Shiyang River Basin, SYR; Yellow River Basin, YR), based on the fish distribution pattern. Additionally, the spatial pattern of species distribution showed the distance decay of taxonomic similarity. Our results demonstrate that riverine connectivity resulting from historical processes plays a vital role in shaping the freshwater ichthyofauna of High Central Asia. These findings will be valuable for future systematic conservation of fish in the Qilian Mountain Basin.