SEARCH · Search USGS

Results for “Plant Ecology”

Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 757 records · Page 42Linked to original sources

USGS2022

Are you sleeping? Are you sleeping? Predicting invasion potential of sleeper species

Sleeper species are non-native species that are established in a region and could become invasive as climate change makes conditions more favorable for many non-native species. Before we can manage potential sleepers, we must first know their identity. We analyzed non-native, established plants in the Northeast United States (CT, MA, ME, NH, NY, RI, VT) using the Environmental Impact Classification for Alien Taxa (EICAT) protocol to identify species that have negative impacts on native ecological communities as well as negative impacts on agriculture, economies, or human health. Here, we highlight four potential sleeper species to watch out for. A full list of potential sleeper species and reported impacts can be found at https://doi.org/10.7275/yfss-tt69.

Connecticut, Maine, Massachusetts, New Hampshire, ↗

USGS1987

Unusual larval habitats and life history of chironomid (Diptera) genera

Ninety-three genera, representing all subfamilies of Chironomidae, are organized into 9 categories of unusual habitats or life history including hygropetric, riparian (bank, floodplain, upland), hyporheic, symbiotic, and intertidal; others live in water held in plants or mine into unusual substrates. In riparian zones precise location of optimum habitat is difficult to determine as is definition of habitat within the continuum from shoreline to upland areas. The ecological importance of the riparian group appears to lie in its processing of coarse particulate matter along the floodplain of streams and rivers. All riparian genera are zoogeographically useful and can be used in reconstructing evolutionary dispersal pathways because they are adapted to unique habits that have remained largely undisturbed by human activities.

Entomologica Scandinavica Supplements↗

USGS1996

Silver Hazards to Fish, Wildlife, and Invertebrates: A Synoptic Review

Ecological and toxicological aspects of silver (Ag) in the environment are briefly summarized with an emphasis on natural resources. Elevated silver concentrations in biota occur in the vicinities of sewage outfalls, electroplating plants, mine waste sites, and silver-iodide seeded areas; in the United States, the photography industry is the major source of anthropogenic silver discharges into the biosphere. Silver and its compounds are not known to be mutagenic, teratogenic, or carcinogenic. Under normal routes of exposure, silver does not pose serious environmental health problems to humans at less than 50.0 ug total Ag/L drinking water or 10.0 ug per cubic meter air. Free silver ion, however, was lethal to representative species of sensitive aquatic plants, invertebrates, and teleosts at nominal water concentrations of 1.2 to 4.9 ug/L; sublethal effects were significant between 0.17 and 0.6 ug/L. Silver was harmful to poultry at concentrations as low as 1.8 mg total Ag/kg whole egg fresh weight by way of injection, 100.0 mg total Ag/L in drinking water, or 200.0 mg total Ag/kg in diets; sensitive mammals were adversely affected at total silver concentrations as low as 250.0 ug/L in drinking water, 6.0 mg/kg in diets, or 13.9 mg/kg whole body.

Contaminant Hazard Reviews↗

USGS2001

Interactions between fire and invasive plants in temperate grasslands of North America

A substantial number of invasive grasses, forbs and woody plants have invaded temperate grasslands in North America. Among the invading species are winter annuals, biennials, cool-season perennials, warm-season perennials, vines, shrubs, and trees. Many of these species have been deliberately introduced and widely planted; some are still used for range improvement, pastures, lawns, and as ornamentals, though many are listed as state or federal noxious weeds. Others have been greatly facilitated by widespread land disturbance. Historically, fire has been a major selective force in the evolution of temperate grasslands. Further, prescribed fire is commonly used as a method of ecological management for native grassland communities as well as in conjunction with restoration efforts. Within this context, it is important to understand how invasive species will interact with natural and prescribed fire regimes. In this paper, we consider what is known about how exotic species that invade temperate grasslands relate to fire. The primary issues addressed for each species are (1) Does fire appear to enhance colonization? (2) To what degree does fire affect the survival of plants? (3) Are plants that are burned able to regrow following fire and, if so, how rapidly can they recover? (4) How important is competition with native species to the response to fire? and (5) What effect does an invasive species have on the characteristics of the fire regime? For many species, results are preliminary, incomplete, or inconsistent among studies. For this reason, many of the conclusions drawn for individual species must be considered preliminary. Based on analyses of individual species, a conceptual framework is presented for considering how invasive plants may interact with fire when they invade an ecosystem. The major categories of influences are the native community, the fire regime, growth conditions for both invasive and native species, and influences that disturbances, human impacts, and landscape characteristics have had in the past and will have in the future. The examples considered in this paper provide support for a few, tentative generalizations. First, among our current worst invaders of temperate grasslands, adaptation to fire is quite variable. Some species are not well adapted to burning and can be easily eliminated; other species are better adapted but can still be eliminated if fire occurs during periods of particular vulnerability and/or at high frequency. There is a set of species that is extremely well adapted to fire and will not be eliminated through burning alone. Second, competitive interactions with native species play a crucial role in the success of nonnative invaders. In cases where differential burn responses between invasive and native species can be exploited, and adequate populations of native dominant species are present, fire can sometimes tip the competitive balance away from invasives. Third, there are a few invasive species that have exceptional attributes and for which there are no easy solutions. The ability of cheatgrass ( Bromus tectorum ) to enhance fire, the ability of Chinese tallow ( Triadica sebifera ) to suppress fire, and the ability of leafy spurge ( Euphorbia esula ) to resprout from repeated injury make these species exceptional threats to native diversity. Finally, the available information for many invasive species is very incomplete, partic- ularly with regard to how fire affects competitive interactions with the native community. There is much more we need to know if we are to consistently predict how invasive species will respond to fire and how burning can best be used to manage for natural diversity.

Conference Paper↗

USGS1995

Sea otters and kelp forests in Alaska: Generality and variation in a community ecological paradigm

Multiscale patterns of spatial and temporal variation in density and population structure were used to evaluate the generality of a three—trophic—level cascade among sea otters (Enhydra lutris), invertebrate herbivores, and macroalgae in Alaska. The paradigm holds that where sea otters occur herbivores are rare and plants are abundant, whereas when sea otters are absent herbivores are relatively common and plants are rare. Spatial patterns were based on 20 randomly placed quadrats at 153 randomly selected sites distributed among five locations with and four locations without sea otters. Both sea urchin and kelp abundance differed significantly among locations with vs. without sea otters in the Aleutian Islands and southeast Alaska. There was little (Aleutian Islands) or no (southeast Alaska) overlap between sites with and without sea otters, in plots of kelp density against urchin biomass. Despite intersite variation in the abundance of kelps and herbivores, these analyses demonstrate that sea otter predation has a predictable and broadly generalizable influence on the structure of Alaskan kelp forests. The percent cover of algal turf and suspension feeder assemblages also differed significantly (although less dramatically) between locations with and without sea otters. Temporal variation in community structure was assessed over periods of from 3 to 15 yr at sites in the Aleutian Islands and southeast Alaska where sea otters were 1) continuously present, 2) continuously absent, or 3) becoming reestablished because of natural range expansion. Kelp and sea urchin abundance remained largely unchanged at most sites where sea otters were continuously present or absent, the one exception being at Torch Bay (southeast Alaska), where kelp abundance varied significantly through time and urchin abundance varied significantly among sites because of episodic and patchy disturbances. In contrast, kelp and sea urchin abundances changed significantly, and in the expected directions, at sites that were being recolonized by sea otters. Sea urchin biomass declined by 50% in the Aleutian Islands and by nearly 100% in southeast Alaska following the spread of sea otters into previously unoccupied habitats. In response to these different rates and magnitudes of urchin reduction by sea otter predation, increases in kelp abundance were abrupt and highly significant in southeast Alaska but much smaller and slower over similar time periods in the Aleutian Islands. The different kelp colonization rates between southeast Alaska and the Aleutian Islands appear to be caused by large—scale differences in echinoid recruitment coupled with size—selective predation by sea otters for larger urchins. The length of urchin jaws (correlated with test diameter, r 2 = 0.968) in sea otter scats indicates that sea urchins <15—20 mm test diameter are rarely eaten by foraging sea otters. Sea urchin populations in the Aleutian Islands included high densities of small individuals (<20 mm test diameter) at all sites and during all years sampled, whereas in southeast Alaska similarly sized urchins were absent from most populations during most years. Small (<30—35 mm test diameter) tetracycline—marked urchins in the Aleutian Islands grew at a maximum rate of °10 mm/yr; thus the population must have significant recruitment annually, or at least every several years. In contrast, echinoid recruitment in southeast Alaska was more episodic, with many years to perhaps decades separating significant events. Our findings help explain regional differences in recovery rates of kelp forests following recolonization by sea otters.

Alaska↗

USGS2002

Ecological evaluation of the abundance and effects of elk herbivory in Rocky Mountain National Park, Colorado, 1994-1999

Several National Park Service units in the Intermountain region possess a number of closely related management needs relative to the abundance of wild ungulates and their herbivory effects on plants and ecosystem processes. In 1993, the then National Biological Service (NBS) - now U.S. Geological Survey, Biological Resources Discipline (USGS, BRD) initiated a series of research studies in four park units in the Intermountain West., into the abundance and effects of ungulates on park ecosystems. Each of these parks received a number of similar research study elements including: (a) a number of new ungulate grazing exclosures (n = 12-21 exclosures per park); (b) aerial survey sightability models to estimate population sizes of ungulates; (e) measures of biomass production and consumption rates near the exclosures and across the landscape; (d) studies of the effects of the grazing on plant abundance, species diversity, and ecosystem effects; and (e) computer model simulations (SAVANNA) of the effects on the ecosystem and plant resources of different ungulate management scenarios. One park unit, Rocky Mountain National Park, Colorado, received funding from the U.S. Geological Survey (USGS, BRD) and parallel funding from NPS for an intensive research study of the effects of elk on the park ecosystems.

Colorado↗

USGS2017

Species’ traits help predict small mammal responses to habitat homogenization by an invasive grass

Invasive plants can negatively affect native species, however, the strength, direction, and shape of responses may vary depending on the type of habitat alteration and the natural history of native species. To prioritize conservation of vulnerable species, it is therefore critical to effectively predict species’ responses to invasive plants, which may be facilitated by a framework based on species’ traits. We studied the population and community responses of small mammals and changes in habitat heterogeneity across a gradient of cheatgrass ( Bromus tectorum ) cover, a widespread invasive plant in North America. We live-trapped small mammals over two summers and assessed the effect of cheatgrass on native small mammal abundance, richness, and species-specific and trait-based occupancy, while accounting for detection probability and other key habitat elements. Abundance was only estimated for the most common species, deer mice ( Peromyscus maniculatus ). All species were pooled for the trait-based occupancy analysis to quantify the ability of small mammal traits (habitat association, mode of locomotion, and diet) to predict responses to cheatgrass invasion. Habitat heterogeneity decreased with cheatgrass cover. Deer mouse abundance increased marginally with cheatgrass. Species richness did not vary with cheatgrass, however, pocket mouse ( Perognathus spp.) and harvest mouse ( Reithrodontomys spp.) occupancy tended to decrease and increase, respectively, with cheatgrass cover, suggesting a shift in community composition. Cheatgrass had little effect on occupancy for deer mice, 13-lined ground squirrels ( Spermophilus tridecemlineatus ), and Ord's kangaroo rat ( Dipodomys ordii ). Species’ responses to cheatgrass primarily corresponded with our a priori predictions based on species’ traits. The probability of occupancy varied significantly with a species’ habitat association but not with diet or mode of locomotion. When considered within the context of a rapid habitat change, such as caused by invasive plants, relevant species’ traits may provide a useful framework for predicting species’ responses to a variety of habitat disturbances. Understanding which species are likely to be most affected by exotic plant invasion will help facilitate more efficient, targeted management and conservation of native species and habitats.

Ecological Applications↗

USGS2019

Soil and stand structure explain shrub mortality patterns following global change–type drought and extreme precipitation

(Bradford) The probability of extreme weather events is increasing, with the potential for widespread impacts to plants, plant communities, and ecosystems. Reports of drought-related tree mortality are becoming more frequent along with increasing evidence that drought accompanied by high temperatures is especially detrimental. Simultaneously, extreme large precipitation events have become more frequent over the past century. Water-limited ecosystems may be more vulnerable to these extreme events than other ecosystems, especially when pushed outside of their historical range of variability. However, drought-related mortality of shrubs—an important component of dryland vegetation—remains understudied relative to tree mortality. In 2014, a landscape-scale die-off of the widespread shrub, big sagebrush (Artemisia tridentata Nutt.), was reported in southwest Wyoming, following extreme hot and dry conditions in 2012 and extremely high precipitation in September of 2013. Here, we examined how severe drought, extreme precipitation, soil texture and salinity, and potential competition contributed to this die-off event. At 98 plots within and around the die-off we quantified big sagebrush mortality, characterized soil texture and salinity, and simulated soil water conditions from 1916-2016 using an ecosystem water balance model. We found that the extreme weather conditions alone did not explain patterns of big sagebrush mortality and did not result in extreme (historically unprecedented) soil water conditions during the drought. Instead, plots with chronically dry soil conditions experienced greatest mortality following the global-change type (hot) drought in 2012. Furthermore, mortality was greater in locations with high potential run-on and low potential run-off where saturated soil conditions were simulated in September 2013, suggesting that extreme precipitation also played an important role in the die-off in these locations. In locations where drought alone contributed to mortality, competition negatively impacted big sagebrush. In locations that may have been affected by both drought and saturation, however, mortality was greatest where competition was lowest, suggesting that these locations may have already been less favorable to big sagebrush. Paradoxically, vulnerability to both extreme events (drought and saturation) was associated with finer-textured soils, and our results highlight the importance of soils in determining local variation the vulnerability of dryland plants to extreme events.

Wyoming↗

USGS2008

Checklists: An under-used tool for the inventory and monitoring of plants and animals

Checklists are widely used to catalog field observations of plants and animals. We used 25 years of bird checklist data from the Études des Populations d’Oiseaux du Quebec program to examine the ability of checklists to produce reliable conservation, management, and ecological information. We found that checklists can provide reliable information on changes in bird populations, phenology, and geographic and climate abundance patterns at local, regional, and continental scales. Professional and amateur conservation groups that need to develop extensive monitoring programs should take advantage of the fact that checklists, unlike other time-consuming and expensive techniques, can be used to detect large-scale changes in an entire community of species.

Quebec↗

USGS2010

Standards for documenting and monitoring bird reintroduction projects

It would be much easier to assess the effectiveness of different reintroduction methods, and so improve the success of reintroductions, if there was greater standardization in documentation of the methods and outcomes. We suggest a series of standards for documenting and monitoring the methods and outcomes associated with reintroduction projects for birds. Key suggestions are: documenting the planned release before it occurs, specifying the information required on each release, postrelease monitoring occurring at standard intervals of 1 and 5 years (and 10 for long-lived species), carrying out a population estimate unless impractical, distinguishing restocked and existing individuals when supplementing populations, and documenting the results. We suggest these principles would apply, largely unchanged, to other vertebrate classes. Similar methods could be adopted for invertebrates and plants with appropriate modification. We suggest that organizations publicly state whether they will adopt these approaches when undertaking reintroductions. Similar standardization would be beneficial for a wide range of topics in environmental monitoring, ecological studies, and practical conservation.

Conservation Letters↗

USGS2006

Users' manual for the Hydroecological Integrity Assessment Process software (including the New Jersey Assessment Tools)

This manual is a user’s guide to four computer software tools that have been developed for the Hydroecological Integrity Assessment Process. The Hydroecological Integrity Assessment Process recognizes that streamflow is strongly related to many critical physiochemical components of rivers, such as dissolved oxygen, channel geomorphology, and water temperature, and can be considered a “master variable” that limits the disturbance, abundance, and diversity of many aquatic plant and animal species. Applying the Hydroecological Integrity Assessment Process involves four steps: (1) a hydrologic classification of relatively unmodified streams in a geographic area using long-term gage records and 171 ecologically relevant indices; (2) the identification of statistically significant, nonredundant, hydroecologically relevant indices associated with the five major flow components for each stream class; and (3) the development of a stream-classification tool and a hydrologic assessment tool. Four computer software tools have been developed.

Open-File Report↗

USGS2021

Developing climate resilience in aridlands using rock detention structures as green infrastructure

The potential of ecological restoration and green infrastructure has been long suggested in the literature as adaptation strategies for a changing climate, with an emphasis on revegetation and, more recently, carbon sequestration and stormwater management. Tree planting and “natural” stormwater detention structures such as bioswales, stormwater detention basins, and sediment traps are popular approaches. However, the experimental verification of performance for these investments is scarce and does not address rock detention structures specifically. This 3-year study investigates the infiltration, peak flow mitigation, and microclimate performance of a natural wash stormwater retention installation using one-rock dams in an urban park in Phoenix, Arizona, USA. Field data collected during the study do not depict change in the hydrogeomorphology. However, hydrologic modeling, using data collected from the field, portrays decreases in peak flows and increases in infiltration at the treated sites. Additionally, we observe a lengthening of microclimate cooling effects following rainfall events, as compared with the untreated sites. In this urban arid land setting, the prospect that rock detention structures themselves could reduce warming or heat effects is promising.

Arizona↗

USGS2011

The humpbacked species richness-curve: A contingent rule for community ecology

Functional relationships involving species richness may be unimodal, monotonically increasing, monotonically decreasing, bimodal, multimodal, U-shaped, or with no discernable pattern. The unimodal relationships are the most interesting because they suggest dynamic, nonequilibrium community processes. For that reason, they are also contentious. In this paper, we provide a wide-ranging review of the literature on unimodal (humpbacked) species richness-relationships. Though not as widespread as previously thought, unimodal patterns of species richness are often associated with disturbance, predation and herbivory, productivity, spatial heterogeneity, environmental gradients, time, and latitude. These unimodal patterns are contingent on organism and environment; we examine unimodal species richness-curves involving plants, invertebrates, vertebrates, plankton, and microbes in marine, lacustrine, and terrestrial habitats. A goal of future research is to understand the contingent patterns and the complex, interacting processes that generate them.

International Journal of Ecology↗

USGS2019

Bunchgrass root abundances and their relationship to resistance and resilience of a burned shrub-steppe landscape

Invasion of exotic annual grasses (EAG) and increased wildfire have motivated an emphasis on managing rangeland plant communities for resistance to invasion and resilience to disturbances. These traits are provided primarily by perennial bunchgrasses in rangelands such as shrub steppe, and specifically but also hypothetically, the abundances and functioning of bunchgrass roots. We asked how bunchgrass root abundances relate to annual grass invasion and to more-readily measured, aboveground indicators of bunchgrass vigor. We used a standardized USDA protocol for root measurement in 445 excavations made in 2016-2018 across a topographically and ecologically varied region of sagebrush steppe burned in 2015 Soda megafire in the Northern Great Basin USA. Nearly all (99%) bunchgrasses, including seedlings, had deeper roots than the surrounding annual grasses (mean depth of annuals = 6.8 ±3.3 cm), and 88% of seedlings remained rooted in response to the “tug test” (uprooting resistance to ~1 kg of upward pull on shoot), with smaller plants (mean height and basal diameters < 20 cm and <2 cm, respectively) more likely to fail the test regardless of their root abundances. Lateral roots of bunchgrasses were scarcer in larger basal gaps (interspace between perennials) but were surprisingly not directly related to cover of surrounding EAG. However, EAG increased with basal gap size and decreased with bunchgrass basal diameter size (in addition to pre-fire EAG abundance), although there was considerable unexplained variability in the relationships. These results provide some support for 1) the importance of basal gaps and bunchgrass diameters as indicators of both vulnerability to annual grass invasion and bunchgrass root abundances, and 2) the need for more detailed methods for root measurement than used here in order to substantiate their usefulness in understanding rangeland resistance and resilience.

Rangeland Ecology and Management↗

USGS2007

Activity, aggression, and habitat use of ruffe ( Gymnocephalus cernuus ) and round goby ( Apollonia melanostoma ) under laboratory conditions

Potential negative ecological interactions between ruffe Gymnocephalus cernuus and round goby Apollonia melanostoma (formerly Neogobius melanostomus ) might affect the colonization dynamics of these invasive species where they are sympatric in the Great Lakes. In order to determine the potential for ecological interactions between these species, we examined the activity, aggression, and habitat use of round gobies and ruffe in single species and mixed species laboratory experiments. Trials included conditions in which food was concentrated (in light or darkness) or scattered. Results showed that ruffe were more active than gobies, particularly when food was scattered. Activity of both species was significantly lower during darkness. Round gobies were significantly more aggressive than ruffe, and total aggression was lower in mixed species trials. Habitat use by ruffe and round gobies overlapped considerably, but we observed significant differences between species in their use of specific habitats that depended on experimental conditions. Overall, ruffe used open habitats more often than did round gobies, primarily when food was scattered. Round gobies used rocks significantly more frequently than did ruffe, but their use of rock habitat decreased during dark conditions. Ruffe were found more often in plant habitats and less often near the wall of the pool in trials during daylight with concentrated food. Activity and habitat use of ruffe and round goby did not significantly differ between single and mixed species trials. Overall, we found little evidence for negative ecological interactions between ruffe and round goby in these laboratory experiments.

Journal of Great Lakes Research↗

USGS2016

Flow regime effects on mature Populus fremontii (Fremont cottonwood) productivity on two contrasting dryland river floodplains

I compared riparian cottonwood ( Populus fremontii ) productivity-discharge relationships in a relictual stand along the highly regulated Green River and in a naturally functioning stand along the unregulated Yampa River in semiarid northwest Colorado. I used multiple regression to model flow effects on annual basal area increment (BAI) from 1982 to 2011, after removing any autocorrelation present. Each BAI series was developed from 20 trees whose mean size (67 cm diameter at breast height [DBH]) was equivalent in the two stands. BAI was larger in the Yampa River stand except in 2 y when defoliating leaf beetles were present there. I found no evidence for a Yampa flood-magnitude threshold above which BAI declined. Flow variables explained &sim;45% of residual BAI variability, with most explained by current-year maximum 90-d discharge (Q M90 ) in the Yampa River stand and by a measure of the year-to-year change in Q M90 in the Green River stand. The latter reflects a management-imposed ceiling on flood magnitude—Flaming Gorge Dam power plant capacity—infrequently exceeded during the study period. BAI in the relictual stand began to trend upward in 1992 when flows started to mimic a natural flow regime. Mature Fremont cottonwoods appear to be ecologically resilient. Their productivity along regulated rivers might be optimized using multiyear environmental flow designs.

Southwestern Naturalist↗

USGS2006

A framework for spatial risk assessments: Potential impacts of nonindigenous invasive species on native species

Many populations of wild animals and plants are declining and face increasing threats from habitat fragmentation and loss as well as exposure to stressors ranging from toxicants to diseases to invasive nonindigenous species. We describe and demonstrate a spatially explicit ecological risk assessment that allows for the incorporation of a broad array of information that may influence the distribution of an invasive species, toxicants, or other stressors, and the incorporation of landscape variables that may influence the spread of a species or substances. The first step in our analyses is to develop species models and quantify spatial overlap between stressor and target organisms. Risk is assessed as the product of spatial overlap and a hazard index based on target species vulnerabilities to the stressor of interest. We illustrate our methods with an example in which the stressor is the ecologically destructive nonindigenous ant, Solenopsis invicta, and the targets are two declining vertebrate species in the state of South Carolina, USA. A risk approach that focuses on landscapes and that is explicitly spatial is of particular relevance as remaining undeveloped lands become increasingly uncommon and isolated and more important in the management and recovery of species and ecological systems. Effective ecosystem management includes the control of multiple stressors, including invasive species with large impacts, understanding where those impacts may be the most severe, and implementing management strategies to reduce impacts. Copyright ?? 2006 by the author(s).

Ecology and Society↗

USGS1989

Regional lists of plant species that occur in wetlands: data base user's guide

The Data Base List of Plant Species that Occur in Wetlands (LIST) currently contains records for 6,728 plant species. Each record provides information on nomenclature, plant characteristics and lifeforms, distribution, and frequency of occurrence in wetlands. The List of Plant Species that Occur in Wetlands, developed to supplement the U.S. Fish and Wildlife Service's Classification of Wetlands and Deepwater Habitats of the United States (Cowardin et al. 1979), underwent an intensive review by field botanists across the country. This review was coordinated by national and regional interagency wetland plant list review panels composed of representatives from the U. S. Fish and Wildlife Service, U. S. Army Corps of Engineers, Soil Conservation Service, and the Environmental Protection Agency. Initial and updated versions of the Data Base List of Plant Species that Occur in Wetlands are available in hardcopy (Reed 1986, 1988). Regional lists are available as U.S. Fish and Wildlife Service Biological Report Series 88(26.126.13). State lists are available as National Ecology Research Center Report Series 88(18.01-18.50). The computerized data base tracks and documents indicator assignments made by regional interagency review panels and facilitates generation of reports. This user's guide describes the format and contents of the LIST Data Base. The Data Base is available on 5-1/4" floppy disks in ASCII format for use with a data base management system on an IBM PC/XT/AT compatible computer. The LIST Data Base was developed using the QUICKTEXT Data Base Management System (Osborn and Strong 1984). Use of QUICKTEXT with the LIST Data Base is strongly recommended. Instructions for loading LIST into QUICKTEXT are included in this user's guide. Other data base management systems capable of handling variable length fields can be used by individuals familiar with these software packages. LIST distribution disks are available for 13 regions (Table 1). QUICKTEXT (course QT100--Data Base Management Techniques) and regional subsets of the LIST Data Base (distributed as self-tutorial courses, Table 1) are available through the Office of Conference Services, Colorado State University.

Report↗