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1.
Military installations provide important native habitat for songbirds, including many species that have experienced population declines in recent decades. As part of the Land Condition Trend Analysis (LCTA) program to monitor animal populations on military lands, we surveyed small (<250 g) breeding landbirds on 60 permanent plots on the Fort Riley Military Installation in northeastern Kansas from 1991 to 2002. During this period, species richness averaged 39.0 species (SE 0.9)/year and mean species richness per plot ranged from 3.6 species (SE=0.2)/plot (1999) to 7.5 species (SE=0.3)/plot (1992). Turnover (the appearance and disappearance of species on all plots from one year to the next) ranged from 5 species (2000–2001) to 16 species (1992–1993) and was driven primarily by turnover of woodland species. We developed an index of relative difference (C) to evaluate relative trends of local populations and found that 25 species declined, 15 species increased, and 7 did not change. Based on migration assemblages, more resident species (6 of 10) and more short-distant migrants (9 of 12) decreased than long-distance migrants (10 vs. 11). Our analysis of major vegetation communities on plots showed few changes in the quantity of habitats (grassland vs. woodlands) during the study. Our results indicate that Fort Riley provides important habitats for many landbirds, particularly those that require grasslands for breeding. Several species exhibited local declines when compared to the regional Breeding Bird Survey routes. We offer an approach that evaluates population changes of small landbirds and provides objective inputs for conservation directives. These can be adopted easily for use on military installations (that use LCTA), parks, and wildlife refuges that have data from annual breeding bird surveys.  相似文献   

2.
Loss of grassland species resulting from activities such as off-road vehicle use increases the need for models that predict effects of anthropogenic disturbance. The relationship of disturbance by military training to plant species richness and composition on two soils (Foard and Lawton) in a mixed prairie area was investigated. Track cover (cover of vehicle disturbance to the soil) and soil organic carbon were selected as measures of short- and long-term disturbance, respectively. Soil and vegetation data, collected in 1-m2 quadrats, were analyzed at three spatial scales (60, 10, and 1 m2). Plant species richness peaked at intermediate levels of soil organic carbon at the 10-m2 and 1-m2 spatial scales on both the Lawton and Foard soils, and at intermediate levels of track cover at all three spatial scales on the Foard soil. Species composition differed across the disturbance gradient on the Foard soil but not on the Lawton soil. Disturbance increased total plant species richness on the Foard soil. The authors conclude that disturbance up to intermediate levels can be used to maintain biodiversity by enriching the plant species pool.  相似文献   

3.
/ Land condition trend analysis (LCTA) is a long-term monitoring program used on military training lands to identify ecological changes that result from training and management activities. We initiated LCTA at the Kansas Army National Guard Training Facility (KANGTF) in Saline County, Kansas, in March 1998. This paper evaluates the LCTA methodology for birds by comparing LCTA results with a modified methodology designed to place sampling transects in field-identified rather than satellite-identified land-cover types. In the satellite-identified land-cover types developed at the site, grassland habitats included a large component of woody vegetation, which resulted in poor resolution of bird assemblages associated with the different land-cover types. Using these cover classes, mixed grass prairie included five grass/forb (g/f) and 10 woody-dependent species; old-field included four g/f and four woody-dependent species; and riparian included one g/f and six woody-dependent species. LCTA sampling was too limited in the ecologically important riparian woodland habitat with the result that bird species were not adequately sampled there. In the alternate sampling strategy, we identified three land-cover classes (grassland, hedgerow, and riparian woodland) by field reconnaissance and increased sampling in the riparian woodland. Grassland included six g/f and three woody-dependent species; hedgerow included six g/f and 20 woody-dependent species, and riparian included two g/f and 19 woody-dependent species. The modifications greatly improved the resolution of bird assemblages associated with land-cover classes at the KANGTF. Use of the alternative sampling method should improve the ability to detect long-term trends in the bird communities.  相似文献   

4.
Section 7(a)(2) of the Endangered Species Act directs federal agencies to ensure that their actions do not jeopardize the continued existence of endangered and threatened species. The US Fish and Wildlife Service (USFWS) issues jeopardy or nonjeopardy biological opinions on proposed federal actions that affect endangered and threatened species. We summarize several biological opinions issued by the USFWS to protect the threatened piping plover (Charadrius melodus). These opinions address federal actions involving hundreds of piping plovers on the Missouri River system and a few piping plover pairs on short stretches of Atlantic coast beach. Some of these opinions are decisive, but most allow the proposed action to proceed conditional upon a lengthy set of reasonable and prudent alternatives to protect the piping plover. These conditions may prove difficult to track and will add to the workload of the USFWS.  相似文献   

5.
This paper analyses regulatory responses to rapid intensification of the use of drones/remotely piloted aircraft (RPA) in the context of wildlife protection. Benefits and disadvantages of the technology to wildlife are examined, before three key limitations in policy and law are identified: failure to address wildlife disturbance in RPA regulation; reliance upon insufficiently comprehensive existing wildlife protection legislation to manage disturbance effects; and limited species-specific research on disturbance. A New Zealand case study further reveals an inconsistent regulatory approach struggling to keep pace with innovation, inadequate regulatory capture of environmental effects due to exemption as “aircraft”, and no recognition that specific geographical locations, such as coastal areas, distinguished by recreational pressures and high numbers of threatened species require special consideration. Recommendations include acknowledging the impact on wildlife in policy, gap analysis of legal arrangements for protection from disturbance (including airspace), and adoption of minimum approach distances to threatened species.  相似文献   

6.
The Land Condition Trend Analysis (LCTA) program is the US Army's standard for land inventory and monitoring, employing standardized methods of natural resources data collection, analyses, and reporting designed to meet multiple goals and objectives. Critical to using LCTA data in natural resources management decisions is the ability of the LCTA protocols to detect changes in natural resources. To quantify the ability of LCTA protocols to detect resource changes, power analysis techniques were used to estimate minimum detectable effect sizes (MDES) for selected primary and secondary management variables for three Army installations. MDES for a subset of primary variables were estimated using data from 27 installation LCTA programs. MDES for primary and secondary variables varied widely. However, LCTA programs implemented at larger installations with lower sampling intensities detected changes in installation resources as well as programs implemented at smaller more intensively sampled installations. As a national monitoring program that is implemented at individual installations, LCTA protocols provide relatively consistent monitoring data to detect changes in resources despite diverse resource characteristics and implementation constraints.  相似文献   

7.
Coastal sandplains provide habitat for a suite of rare and endangered plant and wildlife species in the northeastern United States. These early successional plant communities were maintained by natural and anthropogenic disturbances including salt spray, fire, and livestock grazing, but over the last 150 years, a decrease in anthropogenic disturbance frequency and intensity has resulted in a shift towards woody shrub dominance at the expense of herbaceous taxa. This study quantified the effects of more than a decade of dormant season disturbance-based vegetation management (mowing and prescribed fire) on coastal sandplain plant community composition on Nantucket Island, Massachusetts, USA. We used time-series plant cover data from two similar sites to evaluate the effectiveness of disturbance management for restoring herbaceous species cover and reducing woody shrub dominance. Our results indicate that applying management outside of the peak of the growing season has not been effective in maintaining or increasing the cover of herbaceous species. While management activities resulted in significant (P < 0.01) increases in herbaceous species immediately after treatment, woody species recolonized and dominated treated sites within 3-years post treatment at the expense of graminoids and forbs. These results highlight the difficulties associated with directing ecological succession using disturbance-based management to maintain rare, herbaceous species in coastal sandplain systems that were once a prevalent landscape component under historically chronic anthropogenic disturbance. Further experimentation with growing season disturbance-based management and different combinations of management techniques could provide insights into management alternatives for maintaining herbaceous conservation targets in coastal sandplains.  相似文献   

8.
The effects of military training activities on the land condition of Army installations vary spatially and temporally. Training activities observably degrade land condition while also increasing biodiversity and stabilizing ecosystems. Moreover, other anthropogenic activities regularly occur on military lands such as prescribed burns and agricultural haying—adding to the dynamics of land condition. Thus, spatially and temporally assessing the impacts of military training, prescribed burning, agricultural haying, and their interactions is critical to the management of military lands. In this study, the spatial distributions and patterns of military training-induced disturbance frequency were derived using plot observation and point observation-based method, at Fort Riley, Kansas from 1989 to 2001. Moreover, spatial and variance analysis of cumulative impacts due to military training, burning, haying, and their interactions on the land condition of Fort Riley were conducted. The results showed that: (1) low disturbance intensity dominated the majority of the study area with exception of concentrated training within centralized areas; (2) high and low values of disturbance frequency were spatially clustered and had spatial patterns that differed significantly from a random distribution; and (3) interactions between prescribed burning and agricultural haying were not significant in terms of either soil erosion or disturbance intensity although their means and variances differed significantly between the burned and non-burned areas and between the hayed and non-hayed areas.  相似文献   

9.
Acting under the auspices of the US Endangered Species Act, we quantified wind erosion and its effects on rare and common plant species on a semi-arid military installation in Hawaii. Our goal was to develop management strategies, based on local data, to aid the conservation of rare and common indigenous plants and their habitats. We collected windblown soil coming off of roads and other disturbed soils to assess likely impacts to plants occurring at certain heights and distances from disturbed surfaces. We then subjected plants in a glasshouse to windblown dust treatments, designed from our field data to simulate erosion events, and evaluated the effect of these treatments on photosynthesis and survival. We also designed several field experiments to examine the in-situ effects of windblown soil and soil substrate on germination, growth rate, and survival of indigenous and nonindigenous plants. We conclude from these experiments that most direct effects of windblown soil to plants can be effectively mitigated by locating roads and training areas at least 40 m from sensitive plant habitats and through vegetation management to maintain at least 11% aerial cover on disturbed surfaces. Effects of soil type on germination, growth, and survival was species-specific, emphasizing the importance of species trials prior to, or during, rehabilitation efforts.  相似文献   

10.
The National Wildlife Refuge System is perhaps the most important system of federal lands for protecting wildlife in the United States. Only at refuges has wildlife conservation been legislated to have higher priority than either recreational or commercial activities. Presently, private ranchers and farmers graze cattle on 981,954 ha and harvest hay on 12,021 ha at 123 National Wildlife Refuges. US Fish and Wildlife Service policy is to permit these uses primarily when needed to benefit refuge wildlife. To evaluate the success of this policy, I surveyed grassland management practices at the 123 refuges. The survey results indicate that in fiscal year 1980 there were 374,849 animal unit months (AUMs) of cattle grazing, or 41% more than was reported by the Fish and Wildlife Service. According to managers' opinions, 86 species of wildlife are positively affected and 82 are negatively affected by refuge cattle grazing or haying. However, quantitative field studies of the effect of cattle grazing and haying on wildlife coupled with the survey data on how refuge programs are implemented suggest that these activities are impeding the goal of wildlife conservation. Particular management problems uncovered by the survey include overgrazing of riparian habitats, wildlife mortality due to collisions with cattle fences, and mowing of migratory bird habitat during the breeding season. Managers reported that they spend $919,740 administering cattle grazing and haying; thus refuge grazing and haying programs are also expensive. At any single refuge these uses occupy up to 50% of refuge funds and 55% of staff time. In light of these results, prescribed burning may be a better wildlife management option than is either cattle grazing or haying.  相似文献   

11.
Hawaii possesses abundant geothermal resources and rare native wildlife. Geothermal energy development has not posed a threat to native wildlife in the past, but development potential has recently reached a level at which concern for native wildlife is warranted.Potential geothermal resource areas in Hawaii intersect important native forest and endangered species habitat. The ability of existing laws to constrain development in these areas is in question. State and federal endangered species and environmental reporting laws have little ability to constrain geothermal development on private land. Hawaii's Land Use Law had been viewed by conservationists as protecting natural areas important to native wildlife, but recent decisions of the state Land Board sharply challenge this view.While this dispute was being resolved in the courts, the state legislature passed the Geothermal Subzone Act of 1983. Wildlife value was assessed in the geothermal subzone designation process mandated by this act, but the subzones designated primarily reflected inappropriate developer influence. All areas in which there was developer interest received subzone designation, and no area in which there was no developer interest was subzoned. This overriding emphasis on developer interest violated the intent of the sub-zone act, and trivialized the importance of other assessment criteria, among them native wildlife values.  相似文献   

12.
A “finding of no significant impact” (FONSI) resulting from an environmental assessment (EA) was reported by the US Army in June 1986 for the construction and utilization of a multipurpose range complex (MPRC) at the Pohakuloa Training Area, Hawaii. There was little public response, and the US Fish and Wildlife Service and state agencies were consulted and had few comments concerning the results of the botanical surveys used in the assessment. Construction of the $24 million project was begun in 1988. Near the end of construction in 1989 a lawsuit was filed to halt construction because an environmental impact statement (EIS) had not been done for the project, and the plaintiff thought that significant damage had occurred to several unusual ecosystems. Judgment was against the plaintiff and construction continued. An appeal was filed with the 9th Circuit Court. As MPRC construction was nearly complete, and on advice of Department of Justice lawyers, the Department of Army agreed to settle out of court. The settlement in part called for: (1) the plaintiff to drop the appeal and allow construction to be completed as scheduled, and (2) the Department of Army to prepare an EIS for the operation of the MPRC. A subsequent botanical survey for the EIS discovered one endangered plant species, four category 1 candidate plant species (taxa with sufficient data to support listing as endangered or threatened), three category 2 candidate plant species (taxa with some evidence of vulnerability but insufficient data to support listing at this time), one category 3a species (presumably extinct taxa), and possibly three undescribed species growing within the MPRC boundary. The MPRC case study is an excellent example of why the National Environmental Policy Act (NEPA) must be modified to require in-depth and thorough environmental surveys.  相似文献   

13.
Ecosystem responses to physical or chemical stress may vary from changes in single organisms to alteration of the structure and function of the ecosystem. These responses to stress cannol be predicted exactly. Ecosystems repeatedly exposed to physical and/or chemical stress can be used to study the separate and combined environmental effects of stress. Such studies also allow the development of procedures to select test systems for the analysis of stress in ecosystems. A preliminary field survey of six military training sites at Fort Riley, Kansas, USA, was conducted to identify and verify ecological test systems for evaluating ecosystem responses to physical and/or chemical stress. Comparisons of these data with data collected concurrently from Konza Prairie Research Natural Area reference sites showed that soil microarthropods, some species of macroarthropods, small mammals, and native earthworm species were negatively affected by stress. In contrast, plant species diversity, plant foliage biomass, soil mycorrhizae, and many soil characteristics were within the boundaries of nominal variations observed on “pristine” Konza Prairie. Introduced European earthworms appeared to be positively affected by training activities. This study provided a test of systematic procedures to support impact analysis, ecological toxicology, and ecosystem risk assessments. This is paper IX in D. J. Schaeffer's “Environmental Audit” series.  相似文献   

14.
A procedure is described for conducting floristic examinations of prospective sites of development in order to determine the presence of threatened and/or endangered plant species. The timed meander search procedure provides information to document the level of effort expended in the examination as well as to describe the floristic resources of the site. Tests of the procedure during the 1979 and 1980 field seasons have demonstrated its value both as a means of discovering threatened and endangered species on a site and as a means of documenting a low probability of occurrence of such species if not found during application of the procedure.  相似文献   

15.
Military training activities are known to impact individual species, yet our understanding of how such activities influence animal communities is limited. In this study, we used long-term data in a case study approach to examine the extent to which the local small landbird community differed between a site in northeast Kansas that experienced intensive disturbance from military training activities (Ft. Riley Military Installation) and a similar, nearby site that experienced minimal human disturbance (Konza Prairie Biological Station). In addition, we characterized how the regional pool of potential colonizers influenced local community dynamics using Breeding Bird Survey data. From 1991 to 2001, most species of small terrestrial landbirds (73%) recorded during breeding surveys were found at both sites and the mean annual richness at Ft. Riley (39.0 ± 2.86 [SD]) was very similar to that of Konza Prairie (39.4 ± 2.01). Richness was maintained at relatively constant levels despite compositional changes because colonizations compensated local extinctions at both sites. These dynamics were driven primarily by woodland species that exhibited stochastic losses and gains and were present at a low local and regional abundance. Our results suggest that military training activities may mimic natural disturbances for some species in this area because the small landbird community did not differ markedly between sites with and sites without extensive human disturbance. Although our results suggest that military training is not associated with large changes in the avian community, additional studies are needed to determine if this pattern is found in other ecological communities.  相似文献   

16.
There is increasing awareness of the damage caused to valuable and often unique sensitive habitats by people pressure as degradation causes a loss of plant species, disturbance to wildlife, on-site and off-site impacts of soil movement and loss, and visual destruction of pristine environments. This research developed a new perspective on the problem of recreational induced environmental degradation by assessing the physical aspects of soil erosion using the fallout radionuclide caesium-137 (137Cs). Temporal sampling problems have not successfully been overcome by traditional research methods monitoring footpath erosion and, to date, the 137Cs technique has not been used to estimate longer-term soil erosion in regard to sensitive recreational habitats. The research was based on-sites within Dartmoor National Park (DNP) and the South West Coast Path (SWCP) in south-west England. 137Cs inventories were reduced on the paths relative to the reference inventory (control), indicating loss of soil from the path areas. The Profile Distribution Model estimated longer-term erosion rates (ca. 40 years) based on the 137Cs data and showed that the combined mean soil loss for all the sites on ‘paths’ was 1.41 kg m?2 yr?1 whereas the combined ‘off path’ soil loss was 0.79 kg m?2 yr?1, where natural (non-recreational) soil redistribution processes occur. Recreational pressure was shown to increase erosion in the long-term, as greater soil erosion occurred on the paths, especially where there was higher visitor pressure.  相似文献   

17.
The US Department of Defense (DOD) manages over 10.1 million ha of land, much of which is used for training military personnel. However, vast sections receive little or no use, and military lands have become refuges for many species. At Fort McCoy, Wisconsin, USA, populations of the endangered Karner blue butterfly (Lycaeides melissa samuelis) are found in oak and pine barren communities where wild lupine (Lupinus perennis), a perennial forb required by Karner blue butterfly larvae, still occurs. Oak and pine barren communities are disturbance-dependent, and the barrens ecosystems in the Midwest have declined in extent by 98% because of fire suppression, succession, and habitat fragmentation. We studied the effects of disturbance by military manuever training on the density of lupine and Karner blue butterfly at Fort McCoy. We also wanted to determine whether military training activity could enhance Karner blue butterfly habitat. At locations where tracked vehicles had driven through lupine patches, the abundance of lupine and nectar-producing plants was greater in the median strip between vehicle ruts than in vehicle ruts or 5 m outside the vehicle ruts. The proportion of lupine stems with Karner blue butterfly larvae feeding sign (the ratio of stems fed upon to stems examined) was greater in areas where military vehicles had traveled than where they had not. The proportion of lupine stems with feeding sign and lupine stem density was also positively related to the occurrence of prior bivouacs and fires caused by military munitions. Shrub and forest canopy abundance were lower in areas traveled by tracked vehicles. At the scale of the lupine patch, lupine abundance and the proportion of lupine stems with feeding sign were positively correlated with military training activities, suggesting that maintenance of lupine habitat can be achieved in concert with military training.  相似文献   

18.
/ For regional analyses of species imperilment patterns, data on species distributions are available from the U.S. Fish and Wildlife Service and from the state heritage programs. We compared these two different databases as sources of best available information for regional analyses of patterns of aquatic species imperilment for 132 counties in the southern Appalachians and examined patterns produced from the databases. The heritage program database contained information about a greater number of imperiled species because species need not be federally listed as threatened or endangered to be included in this database. In the southern Appalachians, about half of imperiled molluscs and about one-fourth of imperiled fish were listed as threatened or endangered; much smaller proportions of other taxonomic groups were federally listed. Most threatened and endangered species appeared on both lists, but for about 40% of the species inconsistencies exist, notably a lack of recent records in the heritage program dataset. Numbers of species in each county were significantly different between the two datasets for Georgia, Tennessee, and Virginia, where the largest number of threatened and endangered species reside. Nevertheless, some counties always appeared as centers of imperilment, and the general spatial patterns of imperilment were similar.  相似文献   

19.
Cordylanthus palmatus is a hemiparasitic annual of the family Scrophulareacae. It is on both the federal and state lists of endangered species. Only four widely separated populations remain, all of them in alkali sinks, where the plant thrives in saline-sodic soils. The largest population is at Springtown, Alameda County, California. This article reports on efforts to develop a management plan for both the plant and the alkali sink ecosystem. The plan is based on: (1) characterization of hydrology, soils and geomorphology of the site; (2) characterization of the land use impacts to the site; (3) analysis of plant distribution in relation to gradients of elevation and soil chemistry; (4) studies on water potential and water stress inCordylanthus palmatus and associated species. On the basis of this plan, both the State of California and private groups are cooperating to create, restore, and manage a preserve in the Springtown Alkali Sink.  相似文献   

20.
Concern for the environment has increased over the past century, and the US Congress has responded to this concern by passing legislation designed to protect the nation’s ecological biodiversity. This legislation, culminating with the Endangered Species Act of 1973, has been instrumental in defining methods for identifying and protecting endangered or threatened species and their habitats. Current legislation, however, assumes that the range of a protected species will stay constant over time. This assumption may no longer be valid, as the unprecedented increase in the number and concentration of greenhouse gases in the atmosphere has the potential to cause a global warming of 1.0–4.5°C and a sea-level rise (SLR) of 31–150 cm by the year 2100. Changes in climate of this magnitude are capable of causing shifts in the population structure and range of most animal species. This article examines the effects that SLR may have on the habitats of endangered and threatened species at three scales. At the regional scale 52 endangered or threatened plant and animal species were found to reside within 3 m of mean sea level in the coastal stages of the US Southeast. At the state level, the habitats of nine endangered or threatened animals that may be at risk from future SLR were identified. At the local level, a microscale analysis was conducted in the Cape Romain National Wildlife Refuge, South Carolina, USA, on the adverse effects that SLR may have on the habitats of the American alligator, brown pelican, loggerhead sea turtle, and wood stork. Prepared by the Oak Ridge National Laboratory, Environmental Sciences Division, Oak Ridge, Tennessee 37831, USA; managed by Martin Marietta Energy Systems. Inc. for the US Department of Energy under contract DE-AC05-84OR21400.  相似文献   

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