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1.
Environ Manage ; 62(6): 1007-1024, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30171327

RESUMEN

The persistence of freshwater degradation has necessitated the growth of an expansive stream and wetland restoration industry, yet restoration prioritization at broad spatial extents is still limited and ad-hoc restoration prevails. The River Basin Restoration Prioritization tool has been developed to incorporate vetted, distributed data models into a catchment scale restoration prioritization framework. Catchment baseline condition and potential improvement with restoration activity is calculated for all National Hydrography Dataset stream reaches and catchments in North Carolina and compared to other catchments within the river subbasin to assess where restoration efforts may best be focused. Hydrologic, water quality, and aquatic habitat quality conditions are assessed with peak flood flow, nitrogen and phosphorus loading, and aquatic species distribution models. The modular nature of the tool leaves ample opportunity for future incorporation of novel and improved datasets to better represent the holistic health of a watershed, and the nature of the datasets used herein allow this framework to be applied at much broader scales than North Carolina.


Asunto(s)
Macrodatos , Conservación de los Recursos Hídricos , Ríos/química , Ecosistema , Monitoreo del Ambiente , Hidrología , Nitrógeno/análisis , North Carolina , Fósforo/análisis , Calidad del Agua , Humedales
2.
Environ Sci Technol ; 46(15): 8115-22, 2012 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-22788537

RESUMEN

Surface coal mining is the dominant form of land cover change in Central Appalachia, yet the extent to which surface coal mine runoff is polluting regional rivers is currently unknown. We mapped surface mining from 1976 to 2005 for a 19,581 km(2) area of southern West Virginia and linked these maps with water quality and biological data for 223 streams. The extent of surface mining within catchments is highly correlated with the ionic strength and sulfate concentrations of receiving streams. Generalized additive models were used to estimate the amount of watershed mining, stream ionic strength, or sulfate concentrations beyond which biological impairment (based on state biocriteria) is likely. We find this threshold is reached once surface coal mines occupy >5.4% of their contributing watershed area, ionic strength exceeds 308 µS cm(-1), or sulfate concentrations exceed 50 mg L(-1). Significant losses of many intolerant macroinvertebrate taxa occur when as little as 2.2% of contributing catchments are mined. As of 2005, 5% of the land area of southern WV was converted to surface mines, 6% of regional streams were buried in valley fills, and 22% of the regional stream network length drained watersheds with >5.4% of their surface area converted to mines.


Asunto(s)
Minas de Carbón , Contaminantes del Agua/análisis , Animales , Región de los Apalaches , Invertebrados , Concentración Osmolar , Ríos , Calidad del Agua , West Virginia
3.
J Am Coll Health ; 70(3): 818-823, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-32569511

RESUMEN

ObjectiveTo understand the distribution of healthy and unhealthy food stores near historically black colleges and universities (HBCUs). Participants and methods: Using ArcGIS Pro's network analysis tools and ReferenceUSA database, this study characterized the healthy (favorable) and unhealthy (unfavorable) retail food stores within a 5-mile radius, 15-min driving, and 15-min walking distance from each HBCU in North Carolina. Results: Most retail food stores within a 5-mile buffer radius of the 10 HBCUs in North Carolina were unfavorable. Within 15-min driving from each HBCU, 1082 stores (76.0%) were unfavorable food stores, while 332 (24.0%) were favorable. Additionally, there were four favorable and 35 unfavorable retail food stores within the 15-min walking distance of each HBCU. Conclusions: Favorable food retail stores around HBCUs in North Carolina are limited. Researchers, policy makers, and community stakeholders should work together to improve food environments surrounding HBCUs.


Asunto(s)
Negro o Afroamericano , Sistemas de Información Geográfica , Población Negra , Humanos , Estudiantes , Universidades
4.
Conserv Biol ; 22(1): 140-50, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18254859

RESUMEN

Limitations imposed on species ranges by the climatic, ecological, and physiological effects of elevation are important determinants of extinction risk. We modeled the effects of elevational limits on the extinction risk of landbirds, 87% of all bird species. Elevational limitation of range size explained 97% of the variation in the probability of being in a World Conservation Union category of extinction risk. Our model that combined elevational ranges, four Millennium Assessment habitat-loss scenarios, and an intermediate estimate of surface warming of 2.8 degrees C, projected a best guess of 400-550 landbird extinctions, and that approximately 2150 additional species would be at risk of extinction by 2100. For Western Hemisphere landbirds, intermediate extinction estimates based on climate-induced changes in actual distributions ranged from 1.3% (1.1 degrees C warming) to 30.0% (6.4 degrees C warming) of these species. Worldwide, every degree of warming projected a nonlinear increase in bird extinctions of about 100-500 species. Only 21% of the species predicted to become extinct in our scenarios are currently considered threatened with extinction. Different habitat-loss and surface-warming scenarios predicted substantially different futures for landbird species. To improve the precision of climate-induced extinction estimates, there is an urgent need for high-resolution measurements of shifts in the elevational ranges of species. Given the accelerating influence of climate change on species distributions and conservation, using elevational limits in a tested, standardized, and robust manner can improve conservation assessments of terrestrial species and will help identify species that are most vulnerable to global climate change. Our climate-induced extinction estimates are broadly similar to those of bird species at risk from other factors, but these estimates largely involve different sets of species.


Asunto(s)
Aves/fisiología , Ecosistema , Extinción Biológica , Altitud , Animales , Demografía , Efecto Invernadero , Modelos Biológicos
5.
J Anim Ecol ; 75(2): 466-75, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16637999

RESUMEN

1. The causes of lagged population and geographical range expansions after species introductions are poorly understood, and there are relatively few detailed case studies. 2. We document the 29-year history of population dynamics and structure for a population of Euphydryas gillettii Barnes that was introduced to the Colorado Rocky Mountains, USA in 1977. 3. The population size remained low (< 200 individuals) and confined to a single habitat patch (approximately 2.25 ha) to 1998. These values are similar to those of many other populations within the natural geographical range of the species. 4. However, by 2002 the population increased dramatically to > 3000 individuals and covered approximately 70 ha, nearly all to the south of the original site. The direction of population expansion was the same as that of predominant winds. 5. By 2004, the butterfly's local distribution had retracted mainly to three habitat patches. It thus exhibited a 'surge/contraction' form of population growth. Searches within 15 km of the original site yielded no other new populations. 6. In 2005, butterfly numbers crashed, but all three habitat patches remained occupied. The populations within each patch did not decrease in the same proportions, suggesting independent dynamics that are characteristic of metapopulations. 7. We postulate that this behaviour results, in this species, in establishment of satellite populations and, given appropriate habitat structure, may result in lagged or punctuated expansions of introduced populations.


Asunto(s)
Mariposas Diurnas/fisiología , Ecosistema , Animales , Mariposas Diurnas/crecimiento & desarrollo , Colorado , Femenino , Masculino , Densidad de Población , Dinámica Poblacional , Crecimiento Demográfico , Aislamiento Social
6.
Science ; 309(5734): 603-7, 2005 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-16040704

RESUMEN

We present a global conservation analysis for an entire "flagship" taxon, land mammals. A combination of rarity, anthropogenic impacts, and political endemism has put about a quarter of terrestrial mammal species, and a larger fraction of their populations, at risk of extinction. A new global database and complementarity analysis for selecting priority areas for conservation shows that approximately 11% of Earth's land surface should be managed for conservation to preserve at least 10% of terrestrial mammal geographic ranges. Different approaches, from protection (or establishment) of reserves to countryside biogeographic enhancement of human-dominated landscapes, will be required to approach this minimal goal.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Mamíferos , Agricultura , Animales , Biodiversidad , Bases de Datos Factuales , Países Desarrollados , Países en Desarrollo , Ambiente , Geografía , Humanos , Densidad de Población , Dinámica Poblacional
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