Indicators Of Ecological Health Research Articles

Assessing the spatial occupation and ecological impact of human activities in Chengguan district, Lhasa city, Tibetan Plateau

In this study, the ecological impact of human activities and the space occupied by construction and arable land on the Tibetan Plateau were examined, focusing on changes in the net primary productivity (NPP) as a key indicator of ecological health. With the utilization of land use data and multiyear average NPP data from 2002 to 2020, we analyzed the effects of the conversion of zonal vegetation into construction and arable land on carbon sequestration and oxygen release in Chengguan District, Lhasa city. Our findings indicated a marked spatial difference in the NPP among different land types. Regarding the original zonal vegetation, the NPP ranged from 0.2 to 0.3 kg/m2. Construction land showed a decrease in the NPP, with values ranging from 0.16 to 0.26 kg/m2, suggesting a decrease in ecological productivity. Conversely, arable land exhibited an increase in the NPP, with average values exceeding 0.3 kg/m2. This increase suggested enhanced productivity, particularly in regions where the original zonal vegetation provided lower NPP values. However, this enhanced productivity may not necessarily indicate a positive ecological change. In fact, such increases could potentially disrupt the natural balance of ecosystems, leading to unforeseen ecological consequences. The original zonal vegetation, with NPP values ranging from 0.12 to 0.43 kg/m2, exhibited higher ecological stability and adaptability than the other land types. This wider NPP range emphasizes the inherent resilience of native vegetation, which could sustain diverse ecological functions under varying environmental conditions. These findings demonstrate the urgent need for sustainable land use management on the Tibetan Plateau. This study highlights the importance of considering the ecological impact of land use changes in regional development strategies, ensuring the preservation and enhancement in the unique and fragile plateau ecosystem.

Prokaryotic Community Composition and Diversity in Sediments from Choctafaula, Uphapee, and Cubahatchee Creeks in the Lower Tallapoosa River Basin, Macon County, Alabama: An Observational Study

Sedimentary prokaryotes are primarily responsible for metabolic activity in rivers. They are subjected to a variety of natural and anthropogenic pressures, allowing us to use the composition and diversity of their communities as indicators of ecological health. For our investigation, we looked at sediments from three ecologically critical streams in the Lower Tallapoosa River Basin (Choctafaula, Uphapee, and Cubahatchee Creeks). The prokaryotic community was characterized using molecular approaches, and elemental concentrations were determined by inductively coupled plasma atomic emission spectrometry. This research demonstrated that Proteobacteria (45.02–80.73%), Bacteroidetes (1.98–26.52%), Firmicutes (1.36–50.67%), Actinobacteria (1.55–16.81%), and Acidobacteria (0.13–8.77%) were the most prevalent phyla. Key physicochemical parameters, core communities at multiple taxonomic levels, and several pathogenic genera shifted radically between streams. Weighted and unweighted unifrac distance metrics based PCoA plots indicated the structural and membership similarity of samples from specific creek ecosystems. Based on our research findings, it is evident that the composition and diversity of prokaryotic communities in sediment could serve as significant indicators in stream ecosystems. Further investigation and application of these indicators could prove valuable in assessing the health of streams, particularly in light of the accelerated changes resulting from climate change within a condensed timeframe.

New interactive functional indicator approach for river health assessment in an Asian temperate river: Comprehensive analysis of water chemistry, physical habitat, land use, and the biological disturbance of invasive alien species

Elucidating the responses of aquatic communities to environmental (e.g., chemical, habitat, and flow regime) and biological disturbances is essential to the maintenance and restoration of healthy ecosystems. This study investigated the interactions between environmental and biological disturbance factors and functional indicators of ecological health in 99 sampling sites along a temperate river. Variance tests and multivariate statistical tools, such as non-metric multidimensional scaling (NMDS) and generalized linear models (GLMs), were employed to evaluate the responses of functional indicator guilds and ecological river health to various in-stream chemical, physical, habitat, and land-use pattern factors along with the biological impact of invasive alien species (IAS). Variance testing revealed significant variation (χ2 > 6.2 and p < 0.05) in common species abundance and ecological functional guilds among spatial groups according to chemical pollution levels, land-use intensity, and land-use patterns. NMDS analysis and GLMs based on trophic, habitat, and tolerance guilds, and the results of the multi-metric index of biological integrity for fish, indicated statistically significant patterns in response to environmental disturbance, particularly chemical degradation associated with nutrient (nitrogen and phosphorus) enrichment and organic pollution, loss of gravel and cobble substrates, and intensified agricultural land use. The spatial pattern of IAS abundance was also significantly correlated with the alteration in fish community structures. This study underscores the often-unnoticed impact of high IAS abundance on river health, and its interactions with chemical and physical degradation resulting from agricultural and urban land uses. In summary, this study highlights the importance of addressing multiple environmental and biological disturbances to maintain and conserve the health of river systems.

The Application of the Generalized Additive Model to Represent Macrobenthos near Xiaoqing Estuary, Laizhou Bay.

Macrobenthos is widely used as an indicator of ecological health in marine monitoring and assessment. The present study aimed to characterize the interrelationships between the distribution of the macrobenthos community and environmental factors near Xiaoqing Estuary, Laizhou Bay. Responses of species richness to environmental factors were studied using the generalized additive model (GAM) and the Margalef diversity index (dM) as indicators of species diversity instead of individual indicator species. Six factors were selected in the optimal model by stepwise regression: sediment factors (organic matter, phosphate, nitrate nitrogen, and ammonium nitrogen) and water factors (salinity, and ammonium nitrogen). The response curves generated by the GAM showed a unimodal relationship among taxa diversity, salinity in water, and sediment organic matter. dM was positively correlated with ammonium nitrogen in water and was negatively correlated with phosphate in the sediment. The model optimized by forward stepwise optimization explained 92.6% of the Margalef diversity index with a small residual (2.67). The model showed good performance, with the measured dM strongly correlated with the predicted dM (Pearson R2 = 0.845, p < 0.05). The current study examined the combined influence of multiple eco-factors on macrobenthos, and the Margalef diversity index of macrobenthos was predicted by the GAM model in a salinity-stressed estuary.

Impact On Climate Due to Suspension of Passenger Flights as A Covid-19 Preventive M

Aviation has been a sector that has heavily contributed towards easing lives, addressing transportation needs, and paving the way for new job roles. Since the invention of aircraft, its usage has increased dramatically, which has caused a rampant surge in the frequency of flying. Ever since industrialization, pollution and its harmful effects on the environment have been a pressing issue. Due to this, the airline industry has continuously taken initiatives to protect the atmosphere without disturbing the frequency of flying. Initiatives including better aircraft design, fuel efficiency, optimized routes, restrictions on flight cargo, etc., have been constantly adapted and experimented with to reduce aircrafts’ carbon footprint. Recently, flights had to be suspended on a large scale to avoid coronavirus spread and promote social distancing. Initially, foreign flights were banned from entering Indian soil. The ban was soon extended to domestic travel. This paper focuses on the impact of this preventive measure on the environment. The report follows a systematic approach by analyzing the environmental conditions before and after the suspension of flights in India and checks for significant changes in critical ecological health indicators. The purpose of this paper is to analyze and document the impact of this measure and highlight its benefits, thereby aiding to take novel initiatives at corporate and at government levels to ensure a sustainable future.

Urban watershed ecosystem health assessment and ecological management zoning based on landscape pattern and SWMM simulation: A case study of Yangmei River Basin

Urban watersheds encounter a series of problems in the urbanization process, including water quality degradation, landscape space fragmentation, and ecological degradation. Ecosystem health assessment and ecological management zoning are prerequisites for ecological restoration and watershed sustainability. In terms of ecological integrity and ecosystem services, a watershed ecosystem health assessment framework was constructed in this study. In addition, ecological health indicators were obtained on a grid scale by introducing landscape pattern models, hydrological models, and ecosystem service proxy models. The ecosystem health assessment results of the Yangmei River Basin in 1999, 2013, and 2019 were determined via indicator weighted calculation. The ecological health levels and spatial patterns of different periods were simultaneously compared to analyze the reasons for the dynamic changes in the watershed ecological health. The results showed that due to the impact of human activities, the watershed ecosystem health changed drastically in the western mountains and the southeastern living area from 1999 to 2013. During 2013–2019, the urbanization process triggered changes in the landscape structure, while watershed ecosystem services value increased, and the deterioration of the watershed ecosystem health slowed down. Overall, the watershed ecosystem health has deteriorated in the past 20 years, and the regional differentiation was enlarged. Based on the dynamic changes in the watershed ecological health, five ecological management zones were obtained to help decision-makers formulate reasonable urban watershed ecological restoration plans, ensuring long-term sustainable ecosystem services.

Spatiotemporal effects of interacting water quality constituents on mercury in a common prey fish in a large, perturbed, subtropical wetland

We present results of a multiyear study of the Everglades (Florida, USA) detailing how differences in environmental variables can alter mercury concentrations in the food web. About 1000 random locations throughout the freshwater Everglades marsh have been sampled for the United States Environmental Protection Agency's Everglades Regional Environmental Monitoring and Assessment Program (“REMAP”) since 1995. REMAP sampling is synoptic and multimedia, including an abundant prey fish (eastern mosquitofish, Gambusia holbrooki) as an indicator of mercury bioaccumulation. Amplifying an approach we reported to Everglades National Park, we used Generalized Boosted Models on the REMAP data to estimate how much of the mercury concentration in mosquitofish could be explained by water quality constituents or indicators of ecological health (covariates). The resulting model accounts for 60% of the environmental influence on variation in mosquitofish mercury, a robust outcome for a large, disturbed ecosystem such as the Everglades, given its seasonal, annual, and spatial differences. Of the eight most influential covariates, two were methyl mercury in periphyton and water, two can be indicators of trophic state (alkaline phosphatase and chlorophyll-a), one can be a marker of stormwater transport (conductivity), and two can be enablers of mercury methylation (sulfate in soil and water). While these covariates had an average individual influence ranging from 4.0% to 10.1%, together they accounted for 52.2% of the total relative influence. Water with low phosphorus, but with sulfur and carbon above background, moved into the less disturbed parts of the Everglades via modifications to the existing water management system, could increase mercury bioaccumulation in those parts of the marsh.

Land-use influence on the functional organization of Afrotropical macroinvertebrate assemblages

Studies investigating the effects of human activities on the functional organization of macroinvertebrate communities in tropical streams and rivers are very limited, despite these areas witnessing the greatest loss of natural forests globally. We investigated changes in taxon richness, numerical abundance and biomass of macroinvertebrate functional feeding groups (FFGs) in streams draining different land-use types in the Sosiani-Kipkaren River in western Kenya. Twenty-one sites in river reaches categorized as forested, mixed, urban or agricultural were sampled during the dry and wet seasons. Collected macroinvertebrates were identified to the lowest taxon possible (mainly genus) and classified into five major FFGs; collector-gatherers, collector-filterers, scrapers, predators and shredders. There were significant (p < 0.05) spatial variation in habitat quality, organic matter standing stocks, total suspended solids, electrical conductivity, dissolved oxygen, temperature and nutrient concentrations across land-uses, with forested sites recording lowest values in mean water temperature, electrical conductivity and nutrients while recording highest levels in dissolved oxygen concentrations. Responses in macroinvertebrates to changes in land-use varied with richness, abundance and biomass showing differences within FFGs. Biomass-based metrics responded more strongly to change in land-use while taxon richness was the least predictive, indicating replacement of taxa within FFGs across land-use types. Higher shredder abundance, biomass and richness were recorded in forested streams which were cooler with protected riparian areas and high biomass of coarse particulate organic matter. Collector-gatherers dominated agricultural and urban streams owing to an abundance of particulate organic matter and nutrients, while scrapers responded positively to increased nutrient levels and open canopy in mixed and agricultural streams where primary production and algal biomass was likely increased. Overall, this study provides further evidence of the effects of agricultural and urban land-uses on tropical streams and rivers and contributes to the use of macroinvertebrate FFGs as indicators of ecological health.

Influence of land-derived stressors and environmental variability on compositional turnover and diversity of estuarine benthic communities

It can be challenging to differentiate community changes caused by human activities from the influence of natural background variability. Using gradient forest analysis, we explored the relative importance of environmental factors, operating across multiple spatio-temporal scales, in influencing patterns of compositional turnover in estuarine benthic macroinvertebrate communities across New Zealand. Both land-derived stressors (represented by sediment mud content and total sediment nitrogen and phosphorus content) and natural environmental variables (represented by sea surface temperature, Southern Oscillation Index, and wind-wave exposure) were important predictors of compositional turnover, reflecting a matrix of processes interacting across space and time. Generalized linear models were used to determine whether measures of benthic macroinvertebrate diversity, which are commonly used as indicators of ecological health on a local scale, changed in a way that was consistent with the compositional turnover along the environmental gradient. As expected, compositional turnover along land-derived stressor gradients was negatively associated with diversity indices, suggesting a decline in ecological health as land-derived stressors increase. This study moves towards an ecosystem-based management approach that focusses on cumulative effects rather than single stressors by considering how multiple land-derived stressors influence indicators of estuarine health, against a background of natural variability across several spatio-temporal scales.

Finfish constituents of shrimp trawl low value by-catch off Visakhapatnam, India

With the increase in number of shrimp trawlers operating in Visakhapatnam waters at depths ranging from 20 to 100 m and occasionally even upto 200 m, the problem of by-catch also gradually increasing in this region. Thus it is important to know the finfish species composition in the trawl by-catches in order to develop appropriate management and conservation programs for juvenile finfishes. A total of 280 species of low value finfishes belonging to 80 families and 28 Orders were reported in the trawl by-catches off Visakhapatnam during the study period 2014-17. Moreover, two cardinalfishes namely Apogonichthyoides uninotatus is reported as a new record to the Indian waters and A. pseudotaeniatus has been recorded for the first time from east coast of India. The present paper also compares the constituents of finfish reported during early 90s thus reflecting the changes in species composition. About 112 species of finfishes belonging to 14 families viz . Rhinobatidae, Elopidae, Ophichthidae, Muraenesocidae, Kurtidae, Pomacentridae, Blenniidae, Acropomatidae, Cepolidae, Ephippidae, Datnioidae, Lactariidae, Citharidae and Plueronectidae were represented in by-catch of 1990, and now the representatives of these families have become very rare and could not be collected during the present study period. This study is useful in examining the factors influencing the structure of fish communities and fish species that are important indicators of ecological health.

Sociodemographic, Ecological, and Spatiotemporal Factors Associated with Human Immunodeficiency Virus Drug Resistance in Florida: A Retrospective Analysis.

Persons living with human immunodeficiency virus (HIV) with resistance to antiretroviral therapy are vulnerable to adverse HIV-related health outcomes and can contribute to transmission of HIV drug resistance (HIVDR) when nonvirally suppressed. The degree to which HIVDR contributes to disease burden in Florida-the US state with the highest HIV incidence- is unknown. We explored sociodemographic, ecological, and spatiotemporal associations of HIVDR. HIV-1 sequences (n = 34 447) collected during 2012-2017 were obtained from the Florida Department of Health. HIVDR was categorized by resistance class, including resistance to nucleoside reverse-transcriptase , nonnucleoside reverse-transcriptase , protease , and integrase inhibitors. Multidrug resistance and transmitted drug resistance were also evaluated. Multivariable fixed-effects logistic regression models were fitted to associate individual- and county-level sociodemographic and ecological health indicators with HIVDR. The HIVDR prevalence was 19.2% (nucleoside reverse-transcriptase inhibitor resistance), 29.7% (nonnucleoside reverse-transcriptase inhibitor resistance), 6.6% (protease inhibitor resistance), 23.5% (transmitted drug resistance), 13.2% (multidrug resistance), and 8.2% (integrase strand transfer inhibitor resistance), with significant variation by Florida county. Individuals who were older, black, or acquired HIV through mother-to-child transmission had significantly higher odds of HIVDR. HIVDR was linked to counties with lower socioeconomic status, higher rates of unemployment, and poor mental health. Our findings indicate that HIVDR prevalence is higher in Florida than aggregate North American estimates with significant geographic and socioecological heterogeneity.

The ecological importance of crocodylians: towards evidence-based justification for their conservation.

Large-bodied predators are well represented among the world's threatened and endangered species. A significant body of literature shows that in terrestrial and marine ecosystems large predators can play important roles in ecosystem structure and functioning. By contrast, the ecological roles and importance of large predators within freshwater ecosystems are poorly understood, constraining the design and implementation of optimal conservation strategies for freshwater ecosystems. Conservationists and environmentalists frequently promulgate ecological roles that crocodylians are assumed to fulfil, but often with limited evidence supporting those claims. Here, we review the available information on the ecological importance of crocodylians, a widely distributed group of predominantly freshwater-dwelling, large-bodied predators. We synthesise information regarding the role of crocodylians under five criteria within the context of modern ecological concepts: as indicators of ecological health, as ecosystem engineers, apex predators, keystone species, and as contributors to nutrient and energy translocation across ecosystems. Some crocodylians play a role as indicators of ecosystem health, but this is largely untested across the order Crocodylia. By contrast, the role of crocodylian activities in ecosystem engineering is largely anecdotal, and information supporting their assumed role as apex predators is currently limited to only a few species. Whether crocodylians contribute significantly to nutrient and energy translocation through cross-ecosystem movements is unknown. We conclude that most claims regarding the importance of crocodylians as apex predators, keystone species, ecosystem engineers, and as contributors to nutrient and energy translocation across ecosystems are mostly unsubstantiated speculation, drawn from anecdotal observations made during research carried out primarily for other purposes. There is a paucity of biological research targeted directly at: understanding population dynamics; trophic interactions within their ecological communities; and quantifying the short- and long-term ecological impacts of crocodylian population declines, extirpations, and recoveries. Conservation practices ideally need evidence-based planning, decision making and justification. Addressing the knowledge gaps identified here will be important for achieving effective conservation of crocodylians.

Evidence for the effects of land use on freshwater ecosystems in New Zealand

ABSTRACT To meet the challenges of preventing and reversing adverse effects of land use on ecosystems, management actions need to be founded on strong evidence. We used the pressure-state-impact (PSI) framework to assess evidence of land-use effects on New Zealand freshwater ecosystems. The evidence consisted of published quantitative and categorical associations linking land-use pressures to state changes and ecological impacts in rivers, lakes and aquifers. There was substantial evidence of land-use effects, particularly where land use/land cover (LULC) classes were used as pressure variables. Proportions of catchment area in urban and pastoral LULC were consistently, positively correlated with contaminant levels in water bodies and negatively correlated with ecological-health indicators. Other consistent PSI associations included positive correlations between cattle stocking rates and river contaminant levels, increased fine sediment and decreased ecological-health scores in rivers following forest harvest, and increased river contaminant levels at sites with stock access. Despite these consistent associations, the evidence base has four general shortcomings that should be addressed: (1) inadequate integration of data and models that link land use and contaminant loss to state changes and impacts in freshwater ecosystems; (2) weak inferences based on LULC; (3) reliance on categorical PSI associations; (4) gaps in reported PSI associations.

The Fish Community Index: A Practical Management Tool for Monitoring and Reporting Estuarine Ecological Condition.

Indicators of ecological health based on biological communities, including numerous multimetric indices, are used worldwide to assess and report the condition of aquatic ecosystems such as estuaries. Yet, these tools have rarely been applied to support estuary management in Australia. We present a case study of one such multimetric indicator, the Fish Community Index (FCI), which was developed and applied to quantify the ecological condition of estuaries in southwestern Australia (SWA). We outline the rationale, development, and implementation of the FCI for annual monitoring and reporting of the ecological condition of a highly urbanized estuary, highlighting the key research and management outcomes that it has delivered, and evaluating its potential future applications to support estuary management more broadly, both across Australia and internationally. The FCI is founded upon a conceptually simple and scientifically robust rationale and is sensitive to the ecological stressors that affect many estuaries across the region (e.g., hypoxia, algal blooms). Together with an accompanying annual fish monitoring regime, the FCI provides managers with a consistent, robust basis for quantifying and reporting spatiotemporal changes in estuary condition, with easily comprehensible outputs that facilitate communication with stakeholders, ranging from politicians to the general public. We attribute the successful implementation of this management tool to several characteristics, namely 1) support from a long-term, collaborative partnership between managers and researchers; 2) comprehensive testing and validation of the index prior to implementation; 3) a robust, standardized monitoring regime; and 4) sustained resourcing from managers to implement the index as part of a reporting framework. The FCI has also been applied to other SWA estuaries and could provide a platform for more coordinated assessment and reporting of estuarine condition at the bioregional scale, thereby helping to improve the gap in reporting on the biotic integrity of Australian estuaries. Integr Environ Assess Manag 2019;15:726-738. © 2019 SETAC.

Epidermal Lesions and Injuries of Coastal Dolphins as Indicators of Ecological Health.

Humpback dolphins (genus Sousa), obligatory inshore delphinids, are frequently exposed to adverse effects of many human activities. In Hong Kong, one of the world's most urbanised coastal regions, ~ 50% of the dolphins suffer from at least one type of epidermal lesions, likely related to anthropogenically degraded habitat. Furthermore, one in every ten dolphins has physical injuries indicative of vessel collisions, propeller cuts and fishing-gear entanglements. As top predators with long lifespan, dolphins are good "barometers" of marine environment and their compromised health conditions are symptomatic of increasingly degraded ecological conditions of coastal seas, especially in rapidly developing regions of fast-growing economies.

Projecting the CO2 and Climatic Change Effects on the Net Primary Productivity of the Urban Ecosystems in Phoenix, AZ in the 21st Century under Multiple RCP (Representative Concentration Pathway) Scenarios

Urban vegetation provides ecological services that promote both the ecosystem integrity and human well-being of urban areas, and thus is critical to urban sustainability. As a key indicator of ecological health, net primary productivity (NPP) provides valuable information about the performance of urban ecosystem in response to the changes in urban climate and atmosphere in the 21st century. In this study, a process-based urban ecosystem model, HPM-UEM (Hierarchical Patch Mosaic-Urban Ecosystem Model), was used to investigate spatiotemporal dynamics of urban ecosystem NPP in the Phoenix city, AZ under three representative concentration pathway (RCP2.6, RCP4.5 and RCP8.5) during the 21st century. The results indicated that, by the end of the 21st century, the urban ecosystem’s NPP would increase by 14% (in RCP2.6), 51% (in RCP4.5) and 99% (in RCP8.5) relative to that in the late 2000s, respectively. Factorial analysis indicated that CO2 fertilization effect would be the major driver of NPP change, accounting for 56–61% of the NPP increase under the scenarios. Under the RCP2.6 scenario, the strongest NPP increase would be found in the agricultural lands located in the west and southeast of the city. Under the RCP4.5 and RCP8.5 scenarios, the strongest NPP increase would be found in the mesic residential areas that mainly located to the eastern, southern, and southwestern of the Phoenix Mountains Preserve. Although higher ecosystem NPP in the future implies improved ecosystem services that may help to alleviate the heat stress (by providing more shading) and air pollution in the city, this will be at the cost of higher irrigation water usage, probably leading to water shortage in the natural ecosystems in this arid region. Furthermore, this study indicated the rich (such as in mesic residential area) would enjoy more benefits from the improved urban ecosystem services than the poor (such as in xeric residential area).

Joint Estimation of Bulk Flow Velocity and Angle Using a Lateral Line Probe

Measurement of complex natural flows, especially those occurring in rivers due to man-made structures, is often hampered by the limitations of existing flow measurement methods. Furthermore, there is a growing need for new measurement devices that are capable of measuring the hydrodynamic characteristics of complex natural flows required in environmental studies that often use fish as an indicator of ecological health. In this paper, we take the first step toward in situ natural flow measurements with a new biologically inspired probe design in conjunction with signal processing methods. The device presented in this paper is a dedicated hydrodynamically sensitive sensor array following the fish lateral line sensor modality. Low-level multidimensional sensor signals are transformed to the two key hydrodynamic primitives, bulk flow velocity and bulk flow angle. We show that this can be achieved via canonical signal transformation and kernel ridge regression, allowing velocity estimates with a less than 10 cm/s error. The approach provides robust velocity estimates not only when the sensor is ideally oriented parallel to the bulk flow, but also across the full range of angular deviations up to a completely orthogonal orientation by correcting the pressure field asymmetry for large angular deviations. Furthermore, we show that their joint estimation becomes feasible above a threshold current velocity of 0.45 m/s. The method demonstrated an error of 14 cm/s in velocity estimation in a river environment after training in laboratory conditions.

Evaluation of Chironomidae Diversity in the Little Paint Creek Watershed, Pennsylvania

ABSTRACT The health of a watershed can be assessed by evaluating the benthic macroinvertebrates that are present in the waterways. Benthic chironomid larvae (Diptera: Chironomidae) are often used as a biological indicator of ecological health. The chironomid larvae are particularly tolerant to contaminants, with different taxa exhibiting different levels of tolerance. Thus, evaluation of the abundance and diversity of chironomids within a watershed can be an assessment tool for the biotic health of the watershed. Although several studies of Pennsylvania watersheds have identified the presence of Chironomidae, our study aimed to further understand chironomid diversity by assessing them to the subfamily and genus level. We surveyed eight sites over Little Paint Creek and three tributaries within the Little Paint Creek watershed in southwestern Pennsylvania. By comparing the chironomid abundance and diversity to previously published EPT data for the watershed, our data suggests that water quality of tributary UNT 45234 is better than previously predicted and may be better than that of tributary UNT 45242. The limited number of less tolerant subfamilies of chironomids in the Little Paint Creek samples suggests that this stream may have reduced water quality. We established a baseline of chironomid abundance and diversity within the Little Paint Creek watershed. Our future goal for the project will be to continue to monitor the chironomids at these sites and to compare our findings to areas within the watershed which have been reported to have higher rates of contaminants due to acid mine drainage and Marcellus shale drilling, to determine their effect on aquatic macroinvertebrate diversity.

Epiphytic macrolichen communities correspond to patterns of sulfur and nitrogen deposition in the northeastern United States

Abstract Atmospheric deposition of sulfur (S) and nitrogen (N) has decreased steadily in the northeastern U.S. since the federal 1970 Clean Air Act was passed, yet deposition remains elevated above natural background levels throughout the region. Epiphytic macrolichens are highly sensitive to air pollution and their status is a good indicator of ecological health. We used deposition modeling for 2000–2013 and multiple metrics of lichen status (i.e., species composition, species richness, thallus condition, lichen sensitivity indices, lichen elemental analysis) to assess air pollution effects at 24 plots in four federally-mandated Class I areas. The areas (Lye Brook Wilderness, VT; Great Gulf and the Presidential Range-Dry River Wildernesses, NH; and Acadia National Park, ME) encompass a range of high to low deposition sites. We developed thallus condition scores and sensitivity groups and indices for S and N based on species patterns using deposition estimates gleaned from a larger, independent data base....

Zonal stratification and geographic clustering of a species-rich chironomid community in freshwater coastal rock pools

Chironomidae are typically abundant in freshwater habitats and can be good indicators of ecological health. Coastal rock pools of barrier islands were sampled to determine how communities varied spatially between two horizontal zones, defined by wave disturbance and distance from shore, and from island-to-island. Pupal exuviae were collected monthly from pool surfaces to assess species composition, true community richness, and alpha and beta diversity. Cluster analyses were used to determine geographic community variation. A majority of species were rare, while three species dominated relative abundances. Zonal differences were significant, diversity was greater in near-shore pools overall, and few species occurred in both zones. Communities were more species-rich than expected based on prior studies in similar habitats. Community clusters were not strongly differentiated but suggested increased dispersal challenges at wider gaps between islands. Higher diversity near the shore and geographic clustering of communities are important to consider when planning for remediation activities following pollution events such as ship groundings or oil spills. In general, baseline coastal studies and conservation planning should consider aquatic invertebrates when pool habitats are present.