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At least 559 records · Page 31Linked to original sources

USGS2003

Occurrence and temporal variability of methyl tert -butyl ether (MTBE) and other volatile organic compounds in select sources of drinking water : results of the focused survey

The large-scale use of the gasoline oxygenate methyl tert -butyl ether (MTBE), and its high solubility, low soil adsorption, and low biodegradability, has resulted in its detection in ground water and surface water in many places throughout the United States. Studies by numerous researchers, as well as many State and local environmental agencies, have discovered high levels of MTBE in soils and ground water at leaking underground gasoline-storage-tank sites and frequent occurrence of low to intermediate levels of MTBE in reservoirs used for both public water supply and recreational boating. In response to these findings, the American Water Works Association Research Foundation sponsored an investigation of MTBE and other volatile organic compounds (VOCs) in the Nation's sources of drinking water. The goal of the investigation was to provide additional information on the frequency of occurrence, concentration, and temporal variability of MTBE and other VOCs in source water used by community water systems (CWSs). The investigation was completed in two stages: (1) reviews of available literature and (2) the collection of new data. Two surveys were associated with the collection of new data. The first, termed the Random Survey, employed a statistically stratified design for sampling source water from 954 randomly selected CWSs. The second, which is the focus of this report, is termed the Focused Survey, which included samples collected from 134 CWS source waters, including ground water, reservoirs, lakes, rivers, and streams, that were suspected or known to contain MTBE. The general intent of the Focused Survey was to compare results with the Random Survey and provide an improved understanding of the occurrence, concentration, temporal variability, and anthropogenic factors associated with frequently detected VOCs. Each sample collected was analyzed for 66 VOCs, including MTBE and three other ether gasoline oxygenates (hereafter termed gasoline oxygenates). As part of the Focused Survey, 451 source-water samples and 744 field quality-control (QC) samples were collected from 78 ground-water, 39 reservoir and (or) lake, and 17 river and (or) stream source waters at fixed intervals for a period of 1 year. Using a common assessment level of 0.2 μg/L (micrograms per liter) (2.0 μg/L for methyl ethyl ketone), 37 of the 66 VOCs analyzed were detected in both surveys. However, VOCs, especially MTBE and other gasoline oxygenates, were detected more frequently in the Focused Survey than in the Random Survey. MTBE was detected in 55.5 percent of the CWSs sampled in the Focused Survey and in 8.7 percent of those sampled in the Random Survey. Little difference in occurrence, however, was observed for trihalomethanes (THMs), which were detected in 16.4 and 14.8 percent of Focused Survey and Random Survey CWSs, respectively. This may indicate a pervasive occurrence of THMs in several source-water types, regardless of CWS size or geographic location. Using data at or above the method detection limit to assess temporal variability and anthropogenic factors associated with frequent detection of select VOCs, concentrations in the Focused Survey in ground-water, reservoir, and river source waters were typically less than 1 μg/L. Also, at a 95-percent confidence interval, no statistically significant differences were observed in comparing concentrations in the first and second ground-water sample. A weak seasonal pattern was observed in samples collected from reservoirs and lakes where gasoline oxygenates and other gasoline compounds were detected more frequently during spring and summer, presumedly a result of increased use of motorized watercraft during these seasons. In contrast, seasonal patterns were not observed in samples collected from rivers and streams. The lack of seasonal differences in river and stream source waters sampled may indicate a common and continuous source of contamination. The most frequently detected VOC (MTBE) and the two most frequently occurring subgroups of VOCs (gasoline oxygenates and THMs) detected in CWS source waters were further characterized to evaluate some anthropogenic factors that may better explain their frequent occurrence. Gasoline oxygenates were detected in 73.9 percent of all CWSs sampled. The concentration of gasoline oxygenates was slightly correlated with watercraft use on reservoirs inside MTBE high-use areas (r2=0.3783) but not outside of these areas (r2=0.0242). In general, the concentration of gasoline oxygenates increased as watercraft use increased. THMs were detected in 47.8 percent of the CWSs supplied by surface water. The frequent occurrence of THMs in reservoir source waters was determined to be an artifact of disinfection and the recycling of chlorinated water to these reservoirs. All CWSs with frequent occurrence of THMs served by a reservoir indicated that chlorine was added to waters for various reasons and that the chlorinated water was then released back to, or upstream of, the reservoir or lake that was sampled.

Water-Resources Investigations Report↗

USGS2003

A summary report of sediment processes in Chesapeake Bay and watershed

The Chesapeake Bay, the Nation's largest estuary, has been degraded because of diminished water quality, loss of habitat, and over-harvesting of living resources. Consequently, the bay was listed as an impaired water body due to excess nutrients and sediment. The Chesapeake Bay Program (CBP), a multi-jurisdictional partnership, completed an agreement called "Chesapeake 2000" that revises and establishes new restoration goals through 2010 in the bay and its watershed. The goal of this commitment is the removal of the bay from the list of impaired waterbodies by the year 2010. The CBP is committed to developing sediment and nutrient allocations for major basins within the bay watershed and to the process of examining new and innovative management plans in the estuary itself and along the coastal zones of the bay. However, additional information is required on the sources, transport, and deposition of sediment that affect water clarity. Because the information and data on sediment processes in the bay were not readily accessible to the CBP or to state, and local managers, a Sediment Workgroup (SWGP) was created in 2001. The primary objective of this report, therefore, is to provide a review of the literature on the sources, transport, and delivery of sediment in Chesapeake Bay and its watershed with discussion of potential implications for various management alternatives. The authors of the report have extracted, discussed, and summarized the important aspects of sediment and sedimentation that are most relevant to the CBP and other sediment related-issues with which resources managers are involved. This report summarizes the most relevant studies concerning sediment sources, transport and deposition in the watershed and estuary, sediments and relation to water clarity, and provides an extensive list of references for those wanting more information.

Water-Resources Investigations Report↗

USGS1983

A guide to the larvae of the Nearctic Diamesinae (Diptera; Chironomidae), the genera Boreoheptagyia, Protanypus, Diamesa, and Pseudokiefferiella

The subfamily Diamesinae consists of the monogeneric tribes Boreoheptagnini and Parotanypini and the diverse tribe Diamesini with seven genera. These midges are prevalent in clean, cool arctic-alpine waters, but less abundant in the lowlands. Keys and descriptions herein to the known species of these nine genera may prove valuable in the biomonitoring of these cool aquatic habitats. The larvae of Protanypus saetheri Wiederholm is described for the first time. Identification is based upon the absence of other species in the collection area. Examination of a series of larval D. incallida Walker collected in Wyoming and a review of pertinent literature shows that there is considerable variation in the procerus and the labral armature. Because these characters are often used in keys, this variability can lead to misidentification of less recognizable species of Diamesa. (USGS)

Water-Resources Investigations Report↗

USGS2022

Climate and land use driven ecosystem homogenization in the Prairie Pothole Region

The homogenization of freshwater ecosystems and their biological communities has emerged as a prevalent and concerning phenomenon because of the loss of ecosystem multifunctionality. The millions of prairie-pothole wetlands scattered across the Prairie Pothole Region (hereafter PPR) provide critical ecosystem functions at local, regional, and continental scales. However, an estimated loss of 50% of historical wetlands and the widespread conversion of grasslands to cropland make the PPR a heavily modified landscape. Therefore, it is essential to understand the current and potential future stressors affecting prairie-pothole wetland ecosystems in order to conserve and restore their functions. Here, we describe a conceptual model that illustrates how (a) historical wetland losses, (b) anthropogenic landscape modifications, and (c) climate change interact and have altered the variability among remaining depressional wetland ecosystems (i.e., ecosystem homogenization) in the PPR. We reviewed the existing literature to provide examples of wetland ecosystem homogenization, provide implications for wetland management, and identify informational gaps that require further study. We found evidence for spatial, hydrological, chemical, and biological homogenization of prairie-pothole wetlands. Our findings indicate that the maintenance of wetland ecosystem multifunctionality is dependent on the preservation and restoration of heterogenous wetland complexes, especially the restoration of small wetland basins.

Alberta, Iowa, Manitoba, Minnesota, Montana, North↗

USGS2007

Restoration and rehabilitation of native species in the Great Lakes: Overview

The Laurentian Great Lakes have undergone many changes, both abiotic and biotic, since the early 1900s. Some positive changes have been the relatively recent recovery of some native species and habitats and a concentrated effort toward the recovery of others. The papers in this issue address some of these recoveries and recovery efforts. In addition, an objective of this issue was to communicate ideas and attention to additional research needs. To this end, authors were encouraged to provide novel analyses and hypotheses based on examination of long-term data and reviews of appropriate literature.

Journal of Great Lakes Research↗

USGS2024

Outcomes of control and monitoring of a widespread riparian invader (Tamarix spp.): A comparison of synthesis approaches

Effective ecological restoration requires empirical assessment to determine outcomes of projects, but conclusions regarding the effects of restoration treatments on the whole ecosystem remain rare. Control of invasive shrubs and trees in the genus Tamarix and associated riparian restoration in the American Southwest has been of interest to scientists and resource managers for decades; dozens of studies have reported highly variable outcomes of Tamarix control efforts, as measured by a range of response variables, temporal and spatial scales and monitoring strategies. We conducted a literature search and review, meta-analysis and vote count (comparison of numerical outcomes lacking reported variances and/or sample sizes) on published papers that quantitatively measured a variety of responses to control of Tamarix . From 96 publications obtained through a global search on terms related to Tamarix control, we found 52 publications suitable for a meta-analysis (n = 777 comparisons) and 63 publications suitable for two vote counts (n = 1,460 comparisons total; 622 comparisons reported as statistically significant) of response to Tamarix control. We estimated responses to control by treatment type (e.g. cut-stump treatment, burning, biocontrol) and ecosystem component (e.g. vegetation, fauna, fluvial processes). Finally, we compared results of the various synthesis methods to determine whether the increasingly stringent requirements for inclusion led to biased outcomes. Vegetation metrics, especially measures of Tamarix response, were the most commonly assessed. Ecosystem components other than vegetation, such as fauna, soils and hydrogeomorphic dynamics, were under-represented. The meta-analysis showed significantly positive responses by vegetation overall to biocontrol, herbicide and cut-stump treatments. This was primarily due to reduction of Tamarix cover; impacts on replacement vegetation were highly variable. We found concordance amongst our varied synthesis approaches, indicating that increased granularity from stricter quantitative techniques does not come at the cost of a biased sample. Overall, our results indicate that common control methods are generally effective for reducing Tamarix , but the indirect effects on other aspects of the ecosystem are variable and remain understudied. Given that this is a relatively well-studied invasive plant species, our results also illustrate the limitations of not only individual studies, but also of reviews for measuring the impact of invasive species control. We call on researchers to investigate the less commonly studied responses to Tamarix control and riparian restoration including the effects on fauna, soil and hydrogeomorphic characteristics.

NeoBiota↗

USGS2011

Amphibian responses to wildfire in the western united states: Emerging patterns from short-term studies

The increased frequency and severity of large wildfires in the western United States is an important ecological and management issue with direct relevance to amphibian conservation. Although the knowledge of fire effects on amphibians in the region is still limited relative to most other vertebrate species, we reviewed the current literature to determine if there are evident patterns that might be informative for conservation or management strategies. Of the seven studies that compared pre- and post-wildfire data on a variety of metrics, ranging from amphibian occupancy to body condition, two reported positive responses and five detected negative responses by at least one species. Another seven studies used a retrospective approach to compare effects of wildfire on populations: two studies reported positive effects, three reported negative effects from wildfire, and two reported no effects. All four studies that included plethodontid salamanders reported negative effects on populations or individuals; these effects were greater in forests where fire had been suppressed and in areas that burned with high severity. Species that breed in streams are also vulnerable to post-wildfire changes in habitat, especially in the Southwest. Wildfire is also important for maintaining suitable habitat for diverse amphibian communities, although those results may not be evident immediately after an area burns. We expect that wildfire will extirpate few healthy amphibian populations, but it is still unclear how populations will respond to wildfire in the context of land management (including pre- and post-fire timber harvest) and fragmentation. Wildfire may also increase the risk of decline or extirpation for small, isolated, or stressed (e.g., from drought or disease) populations. Improved understanding of how these effects vary according to changes in fire frequency and severity are critical to form more effective conservation strategies for amphibians in the western United States.

Fire Ecology↗

USGS2021

Climate change risks and adaptation options for Madagascar

Climate change poses an increasing threat to achieving development goals and is often considered in development plans and project designs. However, there have been challenges in the effective implementation of those plans, particularly in the sustained engagement of the communities to undertake adaptive actions, but also due to insufficient scientific information to inform management decisions. Madagascar is a country rich in natural capital and biodiversity but with high levels of poverty, food insecurity, population growth, and exploitation of natural resources. The country faces development and environmental challenges that may be intensified by climate change. The objective of this review is to provide a synthesis of the best-available information regarding climate change impacts on sectoral interests in Madagascar. To do this, we conducted a review of recent literature and conducted formal discussions with development agencies, non-government organizations (NGOs), and other stakeholders. Climate risks in Madagascar include increasing temperatures, reduced and more variable precipitation, more frequent droughts, more intense cyclones, and rising sea levels. We synthesized the observed and projected impacts of climate change on water resources, agriculture, human health, coastal ecosystems, fisheries, and terrestrial ecosystems and ecosystem services, and we discuss ongoing climate adaptation and mitigation activities. Because sectoral challenges and opportunities are linked, coordination among development organizations would be beneficial as they create new climate adaptation and mitigation initiatives.

Ecology and Society↗

USGS2013

Ecological impacts of energy-wood harvests: Lessons from whole-tree harvesting and natural disturbance

Recent interest in using forest residues and small-diameter material for biofuels is generating a renewed focus on harvesting impacts and forest sustainability. The rich legacy of research from whole-tree harvesting studies can be examined in light of this interest. Although this research largely focused on consequences for forest productivity, in particular carbon and nutrient pools, it also has relevance for examining potential consequences for biodiversity and aquatic ecosystems. This review is framed within a context of contrasting ecosystem impacts from whole-tree harvesting because it represents a high level of biomass removal. Although whole-tree harvesting does not fully use the nonmerchantable biomass available, it indicates the likely direction and magnitude of impacts that can occur through energy-wood harvesting compared with less-intensive conventional harvesting and to dynamics associated with various natural disturbances. The intent of this comparison is to gauge the degree of departure of energy-wood harvesting from less intensive conventional harvesting. The review of the literature found a gradient of increasing departure in residual structural conditions that remained in the forest when conventional and whole-tree harvesting was compared with stand-replacing natural disturbance. Important stand- and landscape-level processes were related to these structural conditions. The consequence of this departure may be especially potent because future energy-wood harvests may more completely use a greater range of forest biomass at potentially shortened rotations, creating a great need for research that explores the largely unknown scale of disturbance that may apply to our forest ecosystems.

Journal of Forestry↗

USGS2003

Environmental fate and effects of the lampricide bayluscide: a review

Bayluscide is an additive to TFM that increases the effectiveness of TFM as a lampricide. A review of the literature was undertaken to determine the environmental fate and effects of Bayluscide. Niclosamide (2', 5-dichloro-4'-nitrosalicylanilide), the active ingredient of Bayluscide, degrades rapidly in natural water and sediment systems, however, the rate of degradation is very slow in autoclaved samples. This difference suggests that degradation under laboratory conditions is dependent on microbial activity and hydrolysis plays a minor role in degradation of niclosamide. The major degradation product of niclosamide has been reported to be aminoniclosamide (2',5-dichloro-4'-aminosalicylanilide), which represented more than 50% of the residues extractable from sediments. Significantly more of the chemical is adsorbed to sediments with higher organic content and at lower pH's. The mobility of niclosamide in soil can be characterized as slight to medium; the estimated leaching distance would range from 0 to > 25 cm depending on the soil type and pH. The active ingredient of Bayluscide (niclosamide) is decomposed by ultra-violet light depending on the intensity and duration of the exposure. The uptake of residues by most invertebrates exposed to super(14)C-niclosamide is fairly rapid and equilibrium is reached within 24 h. About 90% of the accumulated residues were lost within 48 h after the organisms were transferred to clean flowing water. As with invertebrates, fish rapidly accumulate and eliminate residues of niclosamide. Three distinct residues were isolated from the extracts of edible fillet tissue; parent niclosamide, the glucuronide conjugate of niclosamide, and the sulfate ester of niclosamide. Aquatic plants and agricultural crops do not appear to be adversely affected at concentrations of Bayluscide used for lamprey or snail control. Mayflies (Hexagenia sp.). tend to be susceptible to TFM, but are relatively resistant to the effects of exposure to Bayluscide. Bayluscide was originally developed as a molluscicide to eliminate snails. Therefore, it is not surprising that mollusks are extremely sensitive to Bayluscide. Oral, dermal, and ocular administration of Bayluscide to mammals resulted in no clinical signs of systemic toxicity. Tests of the chronic effects of Bayluscide indicated that it is not mutagenic or carcinogenic. Bayluscide is not persistent in the environment; it breaks down in natural water and sediment systems through hydrolysis, photolysis, and microbial degradation. Given the limited use and tight control maintained by the U.S. Fish and Wildlife Service during applications of lampricides, Bayluscide presents minimal risk to human health and safety of the environment.

Journal of Great Lakes Research↗

USGS1996

Environmental Contaminants in Wildlife: Interpreting Tissue Concentrations

Covers the complex issue of how to evaluate contaminants in wildlife. This comprehensive resource deals with the question: 'How much of a chemical in the tissues of an animal is harmful?' Features: Authoritative and sound advice is provided on many environmental contaminants, including what the contaminants are and how to interpret the data on them. Each chapter includes a review of the literature on a specific chemical, followed by a clear technical summary that provides research guidance. Direction is given on how to interpret data that are sometimes conflicting or insufficient. Data are presented in easy to use tables. Primary attention is given to toxic concentrations of contaminants such as organochlorine pesticides, PCBs, dioxins, PAHs, metals, and fluorides.

SETAC Special Publications Series.↗

USGS1988

Agricultural chemicals and the quality of prairie-pothole wetlands for adult and juvenile waterfowl - What are the concerns?

A review of the literature and results of ongoing studies indicates that the potential for agricultural chemicals, particularly aerially-applied insecticides, to enter prairie potholes and reduce the quality of these wetlands for waterfowl is great, and that a coordinated effort by farmers, wildlife managers, and regulatory agencies is needed to minimize these impacts

Biological Report↗

USGS1997

A new database on contaminant exposure and effects in terrestrial vertebrates for natural resource managers

The Biomonitoring of Environmental Status and Trends (BEST) program of the Department of the Interior is focused to identify and understand effects of contaminant stressors on biological resources under their stewardship. Despite the desire of many to continuously monitor the environmental health of our estuaries, much can be learned by summarizing existing temporal, geographic, and phylogenetic contaminant information. To this end, retrospective contaminant exposure and effects data for amphibians, reptiles, birds, and mammals residing within 30 km of Atlantic coast estuaries are being assembled through searches of published literature (e.g., Fisheries Review, Wildlife Review, BIOSIS Previews) and databases (e.g., US EPA Ecological Incident Information System; USGS Diagnostic and Epizootic Databases), and compilation of summary data from unpublished reports of government natural resource agencies, private conservation groups, and universities. These contaminant exposure and effect data for terrestrial vertebrates (CEE-TV) are being summarized using Borland dBASE in a 96- field format, including species, collection time and site coordinates, sample matrix, contaminant concentration, biomarker and bioindicator responses, and source of information (N>1500 records). This CEE-TV database has been imported into the ARC/INFO geographic information system (GIS), for purposes of examining geographic coverage and trends, and to identify critical data gaps. A preliminary risk assessment will be conducted to identify and characterize contaminants and other stressors potentially affecting terrestrial vertebrates that reside, migrate through or reproduce in these estuaries. Evaluations are underway, using specific measurement and assessment endpoints, to rank and prioritize estuarine ecosystems in which terrestrial vertebrates are potentially at risk for purposes of prediction and focusing future biomonitoring efforts.

Book chapter↗

USGS1998

International impact research and management

To be sustainable, ecotourism requires the protection of natural environments and processes both from development and operation of the tourism infrastructure, and from the activities of ecotourists within protected areas. This book chapter reviews the international literature on the study of visitor or recreation-related resource impacts with special reference to ecotourism. Four case examples are presented to characterize the geographic scope, focus, and principal findings of this recreation ecology literature and its relevance to ecotourism management. Case examples include the Cairngorms National Nature Reserve, Scotland; the Great Barrier Reef, Australia; the Central American tropics; and wildlife viewing in Kenya?s protected areas. Implications for the management of international protected areas and ecotourism resources are discussed.

Book chapter↗

USGS2000

Ecotoxicology of wild mammals

An international group of 32 scientists has critically reviewed the scientific literature on exposure and effects of environmental contaminants in wild mammals. Although the absolute number of toxicological studies in domesticated and wild mammals eclipses that for birds, a detailed examination of scientific publications and databases reveal that information for 'wild' birds is actually greater than that for 'wild' mammals. Of the various taxa of mammals, ecotoxicological data is most noticeably lacking for marsupials and monotremes. In contrast, rodents (comprising 43% of all mammal species) have been studied extensively, despite evidence of their tolerance to some organochlorine compounds, rodenticides, and even radionuclides. Mammalian species at greatest risk of exposure include those that consume a high percentage of their body weight on a daily basis (e.g., shrews, moles and bats). Aquatic mammals tend to bioaccumulate tremendous burdens of lipophilic contaminants, although storage in their fat depots may actually limit toxicity. Carnivores appear to be more sensitive to adverse effects of environmental contaminants than herbivores. Remarkably few of the thousands of compounds manufactured worldwide have been toxicologically evaluated in wild mammals, and concentrations of even fewer have been monitored in tissues. Overarching research needs include: development of new exposure/effects models and better methods for estimation of species sensitivities; generation of comparative data on contaminant bioavailability, sublethal responses and detoxication mechanisms; enhanced understanding of pesticide, industrial contaminant and metal interactions; identification of endocrine disruptive contaminants and their overall ecological significance; and finally, estimating the relative contribution of environmental contamination as a factor affecting wild mammal populations.

Society of Environmental Toxicology and Chemistry,↗

USGS2001

Trekking poles: Can you save your knees and the environment?

The increasing use of trekking poles has stimulated a growing awareness of some environmental and social impacts associated with their use. These impacts have not been documented in the scientific literature. This article reviews the impacts of trekking pole use to provide a basis for further dialogue, and suggests how they may be altered or used in ways that will minimize impact.

USGS2000

Monitoring hydrilla using two RAPD procedures and the nonindigenous aquatic species database

Hydrilla (Hydrilla verticillata (L.f.) Royle), an invasive aquatic weed, continues to spread to new regions in the United States. Two biotypes, one a female dioecious and the other monoecious have been identified. Management of the spread of hydrilla requires understanding the mechanisms of introduction and transport, an ability to map and make available information on distribution, and tools to distinguish the known U.S. biotypes as well as potential new introductions. Review of the literature and discussions with aquatic scientists and resource managers point to the aquarium and water garden plant trades as the primary past mechanism for the regional dispersal of hydrilla while local dispersal is primarily carried out by other mechanisms such as boat traffic, intentional introductions, and waterfowl. The Nonindigenous Aquatic Species (NAS) database is presented as a tool for assembling, geo-referencing, and making available information on the distribution of hydrilla. A map of the current range of dioecious and monoecious hydrilla by drainage is presented. Four hydrilla samples, taken from three discrete, non-contiguous regions (Pennsylvania, Connecticut, and Washington State) were examined using two RAPD assays. The first, generated using primer Operon G17, and capable of distinguishing the dioecious and monoecious U.S. biotypes, indicated all four samples were of the monoecious biotype. Results of the second assay using the Stoffel fragment and 5 primers, produced 111 markers, indicated that these samples do not represent new foreign introductions. The differences in the monoecious and dioecious growth habits and management are discussed.

Connecticut, Pennsylvania, Washington↗

USGS2002

The flora of Oktibbeha County, Mississippi

We surveyed the flora of Oktibbeha County, Mississippi, U.S.A., from February 1994 to 1996. Occupying 118 square kilometers in east-central Mississippi, Oktibbeha County lies among 3 physiographic regions that include, from west to east, Interior Flatwoods, Pontotoc Ridge, and Black Prairie. Accordingly, the county harbors a diverse flora. Based on field work, as well as an extensive review of published literature and herbarium records at IBE and MISSA, we recorded a total of 1,148 taxa (1,125 species, 7 hybrids, 16 infraspecific taxa) belonging to 514 genera in 160 families, over 85% of all taxa documented were native. Compared to 3 other counties in east-central Mississippi, Oktibbeha County has the second largest recorded flora. The number of state-listed (endangered, threatened, or of special concern) taxa (67) documented in this survey far exceeds that reported from any other county in the region. Three introduced species, Ilex cornuta Lindl. & Paxton, Mahonia bealei (Fortune) Carrie??re, and Nandina domestica Thunb., are reported in a naturalized state for the first time from Mississippi. We also describe 16 different plant communities belonging to 5 broad habitat categories: bottomland forests, upland forests and prairies, aquatic habitats, seepage areas, and human-influenced habitats. A detailed description of the vegetation associated with each of these communities is provided.

SIDA, Contributions to Botany↗