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101.
Federal land management agencies, such as the USDA Forest Service, have expanded the role of recreation partners reflecting
constrained growth in appropriations and broader societal trends towards civic environmental governance. Partnerships with
individual volunteers, service groups, commercial outfitters, and other government agencies provide the USDA Forest Service
with the resources necessary to complete projects and meet goals under fiscal constraints. Existing partnership typologies
typically focus on collaborative or strategic alliances and highlight organizational dimensions (e.g., structure and process)
defined by researchers. This paper presents a partner typology constructed from USDA Forest Service partnership practitioners’
conceptualizations of 35 common partner types. Multidimensional scaling of data from unconstrained pile sorts identified 3
distinct cultural dimensions of recreation partners—specifically, partnership character, partner impact, and partner motivations—that
represent institutional, individual, and socio-cultural cognitive domains. A hierarchical agglomerative cluster analysis provides
further insight into the various domains of agency personnel’s conceptualizations. While three dimensions with high reliability
(RSQ = 0.83) and corresponding hierarchical clusters illustrate commonality between agency personnel’s partnership suppositions,
this study also reveals variance in personnel’s familiarity and affinity for specific partnership types. This real-world perspective
on partner types highlights that agency practitioners not only make strategic choices when selecting and cultivating partnerships
to accomplish critical task, but also elect to work with partners for the primary purpose of providing public service and
fostering land stewardship. 相似文献
102.
Brian M. Shamblin Mark G. Dodd Dean A. Bagley Llewellyn M. Ehrhart Anton D. Tucker Chris Johnson Raymond R. Carthy Russell A. Scarpino Erin McMichael David S. Addison Kristina L. Williams Michael G. Frick Stefanie Ouellette Anne B. Meylan Matthew H. Godfrey Sally R. Murphy Campbell J. Nairn 《Marine Biology》2011,158(3):571-587
The southeastern United States supports one of two large loggerhead turtle (Caretta caretta) nesting aggregations worldwide and is therefore critical to global conservation and recovery efforts for the species. Previous studies have established the presence of four demographically distinct nesting populations (management units) corresponding to beaches from (1) North Carolina through northeastern Florida, (2) peninsular Florida, (3) the Dry Tortugas, and (4) northwest Florida. Temporal and geographic genetic structure of the nesting aggregation was examined utilizing partial mitochondrial control region haplotype frequencies from 834 samples collected over the 2002 through 2008 nesting seasons from 19 beaches as well as previously published haplotype data. Most rookeries did not exhibit interannual genetic variation. However, the interannual variation detected did significantly impact the interpretation of spatial genetic structure in northeastern Florida. Based on pairwise F ST comparisons, exact tests of population differentiation, and analysis of molecular variance, the present study upholds the distinctiveness of the four currently recognized management units and further supports recognition of discrete central eastern, southern (southeastern and southwestern), and central western Florida management units. Further subdivision may be warranted, but more intensive genetic sampling is required. In addition, tools such as telemetry and mark-recapture are needed to complement genetic data and overcome limitations of genetic markers in resolving loggerhead turtle rookery connectivity in the southeastern USA. 相似文献
103.
Eugenia Naro-Maciel Brendan Reid Katherine E. Holmes Daniel R. Brumbaugh Meredith Martin Rob DeSalle 《Marine Biology》2011,158(9):2027-2041
To investigate population differentiation in a comparative and historical context, segments of the mitochondrial cytochrome
c oxidase subunit I gene and the control region were sequenced in Panulirus argus from nine sites along approximately 1,500 km of the Northern Caribbean Sea (n = 326) and analyzed with respect to available panulirid data. A mismatch analysis and Fu’s F
S test uncovered a signature of historical population expansion around the time of the Last Glacial Maximum. Significant population
structure was not detected in the area. The data supported a hypothesis of panmixia resulting from ongoing larval transport
by ocean currents and historical population expansion. Despite high intraspecific divergence levels at COI within Panulirus argus and several other Panulirus species, genetic species identification through DNA barcoding was feasible using either a modified distance threshold or
a character-based approach. 相似文献
104.
Kellner JR Asner GP Kinney KM Loarie SR Knapp DE Kennedy-Bowdoin T Questad EJ Cordell S Thaxton JM 《Ecological applications》2011,21(6):2094-2104
Escape from natural enemies is a widely held generalization for the success of exotic plants. We conducted a large-scale experiment in Hawaii (USA) to quantify impacts of ungulate removal on plant growth and performance, and to test whether elimination of an exotic generalist herbivore facilitated exotic success. Assessment of impacted and control sites before and after ungulate exclusion using airborne imaging spectroscopy and LiDAR, time series satellite observations, and ground-based field studies over nine years indicated that removal of generalist herbivores facilitated exotic success, but the abundance of native species was unchanged. Vegetation cover <1 m in height increased in ungulate-free areas from 48.7% +/- 1.5% to 74.3% +/- 1.8% over 8.4 years, corresponding to an annualized growth rate of lambda = 1.05 +/- 0.01 yr(-1) (median +/- SD). Most of the change was attributable to exotic plant species, which increased from 24.4% +/- 1.4% to 49.1% +/- 2.0%, (lambda = 1.08 +/- 0.01 yr(-1)). Native plants experienced no significant change in cover (23.0% +/- 1.3% to 24.2% +/- 1.8%, lambda = 1.01 +/- 0.01 yr(-1)). Time series of satellite phenology were indistinguishable between the treatment and a 3.0-km2 control site for four years prior to ungulate removal, but they diverged immediately following exclusion of ungulates. Comparison of monthly EVI means before and after ungulate exclusion and between the managed and control areas indicates that EVI strongly increased in the managed area after ungulate exclusion. Field studies and airborne analyses show that the dominant invader was Senecio madagascariensis, an invasive annual forb that increased from < 0.01% to 14.7% fractional cover in ungulate-free areas (lambda = 1.89 +/- 0.34 yr(-1)), but which was nearly absent from the control site. A combination of canopy LAI, water, and fractional cover were expressed in satellite EVI time series and indicate that the invaded region maintained greenness during drought conditions. These findings demonstrate that enemy release from generalist herbivores can facilitate exotic success and suggest a plausible mechanism by which invasion occurred. They also show how novel remote-sensing technology can be integrated with conservation and management to help address exotic plant invasions. 相似文献
105.
Sediment budgets describe the production, transport, deposition and export of sediment in a catchment, and thus provide information useful for planning soil conservation, restoration and monitoring programmes and for evaluating existing and future environmental impacts. Five examples from New Zealand illustrate a variety of sediment budgeting approaches and their use in achieving goals relevant to land-use planning and management. Appropriate sediment budgeting strategies can be selected for a particular application only through careful consideration of the kinds of decisions that will follow from budgeting results. Sediment budget projects can be designed to incorporate the close co-operation between technical experts and clients that results in the most useful sediment budgets. 相似文献
106.
107.
Catherine D. Kashork V. Reid Sutton Jill S. Fonda Allen Deborah E. Schmidt Marisa L. Likhite Lorraine Potocki William E. O'Brien Lisa G. Shaffer 《黑龙江环境通报》2002,22(11):1028-1032
It has been previously reported that a low or absent maternal serum unconjugated estriol (uE3) level is associated with placental steroid sulfatase (STS) deficiency. Here we report a correlation between patients who present with a very low or absent maternal serum uE3 and a deletion of the STS gene as assessed by fluorescence in situ hybridization (FISH). We studied nine prenatal cases that presented to the clinical laboratory with an abnormal triple screen, specifically low or absent maternal serum uE3 and a 46,XY karyotype. FISH analysis showed complete deletion of a probe containing the STS gene in six cases and one case had a partial deletion (reduced but not absent signal). The remaining two cases were not deleted for the STS probe. All mothers tested whose fetus showed a deletion were shown to be STS deletion carriers using FISH. Biochemical analysis was performed on 7/9 prenatal specimens. All fetuses deleted for the STS probe were also found to be deficient for STS by biochemical analysis of cultured amniotic fluid (5/5). Of the two fetuses not deleted for the STS probe, one was deficient for STS activity, while the other had a normal result. The abnormal result of enzyme deficiency by biochemical analysis in a non-deletion case likely represents a mutation in the STS gene, not detectable by this FISH assay. Postnatal FISH confirmation of the STS deletion was performed in 1/7 cases. Clinical follow-up was available for 4/9 cases following birth. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
108.
Ryan Plummer Jonas Velaniškis Danuta de Grosbois Reid D. Kreutzwiser Rob de Loë 《Environmental Science & Policy》2010,13(6):535-548
While new environmental policies and procedures often are developed incrementally, they can also result from crises or other significant events. In situations where policies and procedures are introduced in response to a crisis, questions about the strengths and weaknesses of existing mechanisms, and the extent to which they can be used to address concerns, may be ignored. This paper explores the complexities of introducing new policies and processes where planning systems and procedures already exist. Drinking water source protection policies that are being developed in response to the tragic events in Walkerton, Ontario, Canada serve as the context for the inquiry. Three case study watersheds were selected to reflect the diversity of municipal jurisdictions and water supply systems in Ontario. A content analysis was undertaken on regulatory and non-regulatory policy documents to determine the extent to which they addressed elements of the multi-barrier approach for drinking water safety. Findings from the research reveal considerable evidence of the multi-barrier approach in the policy and guiding documents analyzed. Policy development in response to a crisis can advance progress on the issue of drinking water safety and coincide with emerging governance strategies. Policy effectiveness may be enhanced by considering existing policies as well as contextual and jurisdictional differences. 相似文献
109.
Earthworm assisted bioremediation of organic contaminants 总被引:8,自引:1,他引:7
Due to their biological, chemical and physical actions, earthworms can be directly employed within bioremediation strategies to promote biodegradation of organic contaminants. Earthworms have been shown to aerate and bioturbate soils and improve their nutritional status and fertility, which are variables known to limit bioremediation. Earthworms have also been shown to retard the binding of organic contaminants to soils, release previously soil-bound contaminants for subsequent degradation, and promote and disperse organic contaminant degrading microorganisms. This review discusses these earthworm actions upon the soil environment and how they might influence the fate and behaviour of soil associated organic contaminants, subsequently improving bioremediation potential. The latter part of this review considers organic compounds in the following order: agrochemicals, petroleum and crude oil hydrocarbons, PAHs and PCBs. 相似文献
110.
Ehimai?OhiozebauEmail author Brett?Tendler Allison?Hill Garry?Codling Erin?Kelly John?P.?Giesy Paul?D.?Jones 《Environmental geochemistry and health》2016,38(2):577-591
Concentrations of products of biotransformation of polycyclic aromatic hydrocarbons (PBPAH) were measured in bile of five fishes of nutritional, cultural and ecological relevance from the Athabasca/Slave river system. Samples were collected in Alberta and the Northwest Territories, Canada, during three seasons. As a measure of concentrations of PBPAHs to which fishes are exposed and to gain information on the nature and extent of potential exposures of people or piscivorous wildlife, concentrations of biotransformation products of two- and three-ringed, four-ringed and five-ringed PAHs were measured using synchronous fluorescence spectroscopy. Spatial and seasonal differences were observed with greater concentrations of PBPAHs in samples of bile of fish collected from Fort McKay as well as greater concentrations of PBPAHs in bile of fish collected during summer compared to those collected in other seasons. Overall, PBPAHs were greater in fishes of lower trophic levels and fishes more closely associated with sediments. In particular, goldeye (Hiodon alosoides), consistently contained greater concentrations of all the PBPAHs studied. 相似文献