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1.
Conserv Biol ; 36(3): e13872, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34856018

RESUMO

International demand for wood and other forest products continues to grow rapidly, and uncertainties remain about how animal communities will respond to intensifying resource extraction associated with woody bioenergy production. We examined changes in alpha and beta diversity of bats, bees, birds, and reptiles across wood production landscapes in the southeastern United States, a biodiversity hotspot that is one of the principal sources of woody biomass globally. We sampled across a spatial gradient of paired forest land-uses (representing pre and postharvest) that allowed us to evaluate biological community changes resulting from several types of biomass harvest. Short-rotation practices and residue removal following clearcuts were associated with reduced alpha diversity (-14.1 and -13.9 species, respectively) and lower beta diversity (i.e., Jaccard dissimilarity) between land-use pairs (0.46 and 0.50, respectively), whereas midrotation thinning increased alpha (+3.5 species) and beta diversity (0.59). Over the course of a stand rotation in a single location, biomass harvesting generally led to less biodiversity. Cross-taxa responses to resource extraction were poorly predicted by alpha diversity: correlations in responses between taxonomic groups were highly variable (-0.2 to 0.4) with large uncertainties. In contrast, beta diversity patterns were highly consistent and predictable across taxa, where correlations in responses between taxonomic groups were all positive (0.05-0.4) with more narrow uncertainties. Beta diversity may, therefore, be a more reliable and information-rich indicator than alpha diversity in understanding animal community response to landscape change. Patterns in beta diversity were primarily driven by turnover instead of species loss or gain, indicating that wood extraction generates habitats that support different biological communities.


Conservación de la Diversidad Alfa y Beta en Paisajes de Producción Maderera Resumen La demanda internacional de madera y otros productos forestales sigue creciendo rápidamente mientras permanecen las incertidumbres sobre cómo responderán las comunidades animales a la intensificación de la extracción de recursos asociada con la producción de bioenergía leñosa. Examinamos los cambios en la diversidad alfa y beta de murciélagos, abejas, aves y reptiles en los paisajes de producción maderera en el sureste de los Estados Unidos, un punto caliente de biodiversidad y una de las fuentes principales de biomasa leñosa a nivel mundial. Muestreamos a lo largo de un gradiente espacial de usos de suelo forestales emparejados (representando la pre- y postcosecha) que nos permitió evaluar los cambios en las comunidades biológicas resultantes de varios tipos de recolección de biomasa. Las prácticas de corta rotación y de eliminación de residuos después de la tala estuvieron asociadas con la reducción de la diversidad alfa (−14.1 y −13.9 especies, respectivamente) y una diversidad beta más baja (es decir, diferencia de Jaccard) entre los pares de uso de suelo (0.46 y 0.50, respectivamente), mientras que el raleo de rotación media incrementó la diversidad alfa (+3.5 especies) y beta (0.59). Durante la duración de una rotación permanente en una sola ubicación, la cosecha de biomasa generalmente derivó en menos biodiversidad. La respuesta de los taxones a la extracción de recursos estuvo muy mal pronosticada por la diversidad alfa: la correlación de las respuestas entre los grupos taxonómicos fue altamente variable (−0.2 a 0.4) con muchas incertidumbres. Como contraste, los patrones de diversidad beta fueron fuertemente coherentes y predecibles en todos los taxones, mientras que la correlación de las respuestas entre los grupos taxonómicos siempre fue positiva (0.05 a 0.4) con incertidumbres más limitadas. Por lo tanto, la diversidad beta puede ser un indicador más confiable y rico en información que la diversidad alfa para entender las respuestas de la comunidad animal a los cambios en el paisaje. Los patrones de la diversidad beta estuvieron impulsados principalmente por la rotación en lugar de la pérdida o ganancia de especies, lo que indica que la extracción de madera genera hábitats que mantienen a diferentes comunidades biológicas.


Assuntos
Conservação dos Recursos Naturais , Madeira , Animais , Biodiversidade , Ecossistema , Florestas
2.
Rev. colomb. quím. (Bogotá) ; 50(2): 15-23, mayo-ago. 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1341312

RESUMO

Abstract Agave cocui vinasse was physicochemically characterized with reference to the relevant environmental regulations. The following results were obtained: COD: 71,000 mg.L-1, total solids: 21,000 mg.L-1, dissolved solids: 17,000 mg.L-1; pH: 4.06, conductivity: 9.45 mhoscm-1, total Fe: 48.83 mg.L-1, total phenols: 8.66 mg.L-1; BOD: 30,000 mg.L-1. Fenton and photo-Fenton reactions were applied to treat the wastewater produced. For the Fenton process, the optimal oxidation conditions found were pH = 3.48, [COD]:[H2O2] mass ratio = 1:5, and [Fe+2]: [H2O2] mass ratio = 1:6. For the photo-Fenton process, the optimal parameters found were: pH = 3.98, [COD]:[H2O2] = 1:7.86, and [Fe+2]: [H2O2] = 1:5. The experimental data were adjusted to fit second order polynomial models with R2 = 0.88 for the Fenton process and R2 = 0.91 for the photo-Fenton process, respectively. The sludge produced featured the following characteristics: average COD: 41,000 mg.L-1, total Fe: 296,000 mg.L-1, pH: 7.7. The variables with the greatest influence in both processes were [Fe+2]:[H2O2] and [COD]:[H2O2].


Resumen Se caracterizó fisicoquímicamente la vinaza de Agave cocui con base en regulaciones ambientales de referencia. Se obtuvieron los siguientes resultados: DQO: 71 000 mg.L-1, sólidos totales: 21 000 mg.L-1, sólidos disueltos: 17 000 mg.L-1; pH: 4,06, conductividad: 9,45 mhos.cm-1, hierro total: 48,83 mg.L-1, fenoles totales: 8,66 mg.L-1 ; DBO: 30 000 mg.L-1. Se aplicaron las reacciones Fenton y foto Fenton para tratar las aguas residuales producidas. Para el proceso Fenton, las condiciones de oxidación óptimas encontradas fueron pH = 3,48, relación de masa [DQO]:[H2O2] = 1:5 y relación de masa [Fe+2]:[H2O2] = 1:6. Para el proceso foto Fenton, los parámetros óptimos encontraron fueron: pH = 3,98, [DQO]:[H2O2] = 1:7,86 y [Fe+2]:[H2O2] = 1:5. Los datos experimentales fueron ajustados a modelos de segundo orden polinomial con R2 = 0,88 para el proceso Fenton y R2 = 0,91 para el proceso foto Fenton, respectivamente. El lodo producido presentó las siguientes características: DQO promedio: 41 000 mg.L-1, hierro total: 296 000 mg.L-1, pH: 7,7. Las variables con mayor influencia en ambos procesos fueron [Fe+2]:[H2O2] and [DQO]: [H2O2].


Resumo A vinhaça de Agave cocui foi caracterizada físico-quimicamente de acordo com as normas ambientais de referência. Os seguintes resultados foram obtidos: DQO: 71.000 mg.L-1, sólidos totais: 21.000 mg.L-1, sólidos dissolvidos: 17.000 mg.L-1; pH: 4,06, condutividade: 9,45 mhos.cm-1, Fe total: 48,83 mg.L-1, fenóis totais: 8,66 mg.L-1; DBO: 30,000 mg.L-1. As reações de Fenton e foto Fenton foram aplicadas para tratar a água residual produzida. Para o processo Fenton, as condições de oxidação ideais encontradas foram pH = 3,48, razão de massa [DQO]:[H2O2] = 1:5 e razão de massa [Fe+2]:[H2O2] = 1:6. Para o processo de foto Fenton, os parâmetros ideais encontrados foram: pH = 3,98, [DQO]:[H2O2] = 1:7,86 e [Fe+2]:[H2O2] = 1:5. Os dados experimentais foram ajustados para se adequar modelos polinomiais de segunda ordem com R2 = 0,88 para o processo Fenton e R2 = 0,91 para o processo foto Fenton, respectivamente. O lodo produzido apresentou as seguintes características: DQO média: 41.000 mg.L-1, Fe total: 296.000 mg.L-1, pH: 7,7. As variáveis com maior influência em ambos os processos foram [Fe+2]:[H2O2] e [DQO]:[H2O2].

3.
Conserv Biol ; 29(1): 12-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25040040

RESUMO

Mitigation translocation of nuisance animals is a commonly used management practice aimed at resolution of human-animal conflict by removal and release of an individual animal. Long considered a reasonable undertaking, especially by the general public, it is now known that translocated subjects are negatively affected by the practice. Mitigation translocation is typically undertaken with individual adult organisms and has a much lower success rate than the more widely practiced conservation translocation of threatened and endangered species. Nonetheless, the public and many conservation practitioners believe that because population-level conservation translocations have been successful that mitigation translocation can be satisfactorily applied to a wide variety of human-wildlife conflict situations. We reviewed mitigation translocations of reptiles, including our own work with 3 long-lived species (Gila monsters [Heloderma suspectum], Sonoran desert tortoises [Gopherus morafkai], and western diamond-backed rattlesnakes [Crotalus atrox]). Overall, mitigation translocation had a low success rate when judged either by effects on individuals (in all studies reviewed they exhibited increased movement or increased mortality) or by the success of the resolution of the human-animal conflict (translocated individuals often returned to the capture site). Careful planning and identification of knowledge gaps are critical to increasing success rates in mitigation translocations in the face of increasing pressure to find solutions for species threatened by diverse anthropogenic factors, including climate change and exurban and energy development.


Assuntos
Conservação dos Recursos Naturais/métodos , Espécies em Perigo de Extinção , Répteis/fisiologia , Animais , Arizona , Crotalus/fisiologia , Lagartos/fisiologia , Tartarugas/fisiologia
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