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1.
Conserv Biol ; 33(2): 413-422, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30346052

RESUMEN

Wind energy development is the most recent of many pressures on upland bird communities and their habitats. Studies of birds in relation to wind energy development have focused on effects of direct mortality, but the importance of indirect effects (e.g., displacement, habitat loss) on avian community diversity and stability is increasingly being recognized. We used a control-impact study in combination with a gradient design to assess the effects of wind farms on upland bird densities and on bird species grouped by habitat association (forest and open-habitat species). We conducted 506 point count surveys at 12 wind-farm and 12 control sites in Ireland during 2 breeding seasons (2012 and 2013). Total bird densities were lower at wind farms than at control sites, and the greatest differences occurred close to turbines. Densities of forest species were significantly lower within 100 m of turbines than at greater distances, and this difference was mediated by habitat modifications associated with wind-farm development. In particular, reductions in forest cover adjacent to turbines was linked to the observed decrease in densities of forest species. Open-habitat species' densities were lower at wind farms but were not related to distance from turbines and were negatively related to size of the wind farm. This suggests that, for these species, wind-farm effects may occur at a landscape scale. Our findings indicate that the scale and intensity of the displacement effects of wind farms on upland birds depends on bird species' habitat associations and that the observed effects are mediated by changes in land use associated with wind-farm construction. This highlights the importance of construction effects and siting of turbines, tracks, and other infrastructure in understanding the impacts of wind farms on biodiversity.


Efectos del Desarrollo de la Energía Eólica y los Cambios Asociados al Uso de Suelo sobre las Densidades de Aves en Tierras Altas Resumen El desarrollo de la energía eólica es la más reciente de muchas presiones ejercidas sobre las comunidades de aves de tierras altas y sus hábitats. Los estudios sobre aves en relación con el desarrollo de la energía eólica se han enfocado en los efectos de la mortalidad directa, pero la importancia de los efectos indirectos (p. ej.: desplazamiento, pérdida de hábitat) sobre la diversidad y estabilidad de las comunidades aviares cada vez se reconoce más. Usamos un estudio de control-impacto combinado con un diseño de gradiente para evaluar los efectos de los campos eólicos sobre las densidades de aves de tierras altas y sobre las especies de aves agrupadas por asociación de hábitat (especies de bosque y de hábitat abierto). Realizamos 506 censos de conteo por puntos en 12 sitios de campos eólicos y 12 sitios control en Irlanda durante dos temporadas de reproducción (2012 y 2013). Las densidades de aves totales fueron más bajas en los campos eólicos que en los sitios control, con las diferencias más importantes ocurriendo cerca de las turbinas. Las densidades de las especies de bosque fueron significativamente más bajas a 100 m de las turbinas que a distancias mayores y esta diferencia estuvo mediada por modificaciones asociadas con el desarrollo de campos eólicos. De manera particular, las reducciones en la cobertura de bosque adyacente a las turbinas estuvieron vinculadas con la disminución observada en las densidades de las especies de bosque. Las densidades de las especies de hábitat abierto fueron más bajas en los campos eólicos pero no estuvieron relacionadas con la distancia a las turbinas y tuvieron una relación negativa con el tamaño del campo eólico. Lo anterior sugiere que, para estas especies, los efectos del campo eólico pueden ocurrir a la escala de paisaje. Nuestros hallazgos indican que la escala y la intensidad de los efectos de desplazamiento de los campos eólicos sobre las aves de tierras altas dependen de las asociaciones de hábitat de las especies de aves y que los efectos observados están mediados por cambios en el uso de suelo asociados con la construcción de campos eólicos. Esto remarca la importancia de los efectos de construcción y el sitiado de las turbinas, pistas y demás infraestructura en el entendimiento de los impactos que tienen los campos eólicos sobre la biodiversidad.


Asunto(s)
Conservación de los Recursos Naturales , Fuentes Generadoras de Energía , Animales , Aves , Ecosistema , Viento
2.
Ecol Appl ; 28(6): 1396-1412, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29923353

RESUMEN

We summarize the results of a recent interagency assessment of land carbon dynamics in Alaska, in which carbon dynamics were estimated for all major terrestrial and aquatic ecosystems for the historical period (1950-2009) and a projection period (2010-2099). Between 1950 and 2009, upland and wetland (i.e., terrestrial) ecosystems of the state gained 0.4 Tg C/yr (0.1% of net primary production, NPP), resulting in a cumulative greenhouse gas radiative forcing of 1.68 × 10-3  W/m2 . The change in carbon storage is spatially variable with the region of the Northwest Boreal Landscape Conservation Cooperative (LCC) losing carbon because of fire disturbance. The combined carbon transport via various pathways through inland aquatic ecosystems of Alaska was estimated to be 41.3 Tg C/yr (17% of terrestrial NPP). During the projection period (2010-2099), carbon storage of terrestrial ecosystems of Alaska was projected to increase (22.5-70.0 Tg C/yr), primarily because of NPP increases of 10-30% associated with responses to rising atmospheric CO2 , increased nitrogen cycling, and longer growing seasons. Although carbon emissions to the atmosphere from wildfire and wetland CH4 were projected to increase for all of the climate projections, the increases in NPP more than compensated for those losses at the statewide level. Carbon dynamics of terrestrial ecosystems continue to warm the climate for four of the six future projections and cool the climate for only one of the projections. The attribution analyses we conducted indicated that the response of NPP in terrestrial ecosystems to rising atmospheric CO2 (~5% per 100 ppmv CO2 ) saturates as CO2 increases (between approximately +150 and +450 ppmv among projections). This response, along with the expectation that permafrost thaw would be much greater and release large quantities of permafrost carbon after 2100, suggests that projected carbon gains in terrestrial ecosystems of Alaska may not be sustained. From a national perspective, inclusion of all of Alaska in greenhouse gas inventory reports would ensure better accounting of the overall greenhouse gas balance of the nation and provide a foundation for considering mitigation activities in areas that are accessible enough to support substantive deployment.


Asunto(s)
Ciclo del Carbono , Cambio Climático , Ecosistema , Alaska , Política Ambiental , Predicción
3.
Med Vet Entomol ; 32(2): 235-243, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29194726

RESUMEN

Ixodes ricinus (Ixodida: Ixodidae) ticks are of economic and pathogenic importance across Europe. Within the uplands of the U.K., management to reduce ticks is undertaken to benefit red grouse Lagopus lagopus scotica (Galliformes: Phasianidae). Management strategies focus on the acaricide treatment of domestic sheep Ovis aries (Artiodactyla: Bovidae), but the effectiveness of this is less certain in the presence of wild hosts, particularly red deer Cervus elaphus (Artiodactyla: Cervidae) and mountain hare Lepus timidus (Lagomorpha: Leporidae). This study examines the effects of sheep management on grouse tick burdens and productivity using sites with a range of wild host densities. Sites at which applications of acaricide were more frequent had lower tick burdens; this relationship was similar on sites with a range of deer densities. However, no direct link was detected between acaricide treatment interval and grouse productivity. Sites with higher deer densities had higher grouse tick burdens and lower productivity [mean ± standard error (SE) young : adult ratio: 1.2 ± 0.2] compared with sites with lower deer densities (mean ± SE young : adult ratio: 1.8 ± 0.1). Sites with higher grouse brood sizes and higher proportions of hens with broods were also those with higher mountain hare abundance indices. This study highlights the importance of the frequent treatment of sheep with acaricide to reduce tick burdens on grouse, even in the presence of wild hosts.


Asunto(s)
Acaricidas/administración & dosificación , Enfermedades de las Aves/prevención & control , Galliformes , Enfermedades de las Ovejas/prevención & control , Control de Ácaros y Garrapatas/estadística & datos numéricos , Infestaciones por Garrapatas/veterinaria , Animales , Conservación de los Recursos Naturales , Ciervos/fisiología , Femenino , Liebres/fisiología , Densidad de Población , Escocia , Ovinos , Infestaciones por Garrapatas/prevención & control
4.
Disasters ; 39(3): 546-69, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25583064

RESUMEN

The United Kingdom has experienced several exceptional summer flash floods in recent years and there is growing concern about the frequency of such events and the preparedness of the population. This paper uses a case study of the upper Ryedale flash flood (2005) and questionnaire and interview data to assess local perceptions of upland flash flooding. Experience of a major flash flood may not be associated with increased flood risk perception. Despite local residents' awareness of a trend towards wetter summers and more frequent heavy rainfall, the poor maintenance of rivers was more frequently thought to be a more significant factor influencing local flood risk than climate change. Such findings have important implications for the potential success of contemporary national flood policies, which have put greater emphasis on public responsibility for responding to flooding. This study recommends, therefore, the use of fresh participatory approaches to redistribute and raise awareness of locally-held flood knowledge.


Asunto(s)
Desastres , Inundaciones , Femenino , Inundaciones/estadística & datos numéricos , Humanos , Masculino , Lluvia , Medición de Riesgo , Ríos , Estaciones del Año , Reino Unido
5.
J Environ Manage ; 128: 345-62, 2013 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-23774752

RESUMEN

A methodological framework is proposed for participatory scenario development on the basis of evidence from the literature, and is tested and refined through the development of scenarios for the future of UK uplands. The paper uses a review of previous work to justify a framework based around the following steps: i) define context and establish whether there is a basis for stakeholder engagement in scenario development; ii) systematically identify and represent relevant stakeholders in the process; iii) define clear objectives for scenario development with stakeholders including spatial and temporal boundaries; iv) select relevant participatory methods for scenario development, during initial scenario construction, evaluation and to support decision-making based on scenarios; and v) integrate local and scientific knowledge throughout the process. The application of this framework in case study research suggests that participatory scenario development has the potential to: i) make scenarios more relevant to stakeholder needs and priorities; ii) extend the range of scenarios developed; iii) develop more detailed and precise scenarios through the integration of local and scientific knowledge; and iv) move beyond scenario development to facilitate adaptation to future change. It is argued that participatory scenario development can empower stakeholders and lead to more consistent and robust scenarios that can help people prepare more effectively for future change.


Asunto(s)
Participación de la Comunidad/métodos , Conservación de los Recursos Naturales/métodos , Modelos Teóricos , Reino Unido
6.
Zootaxa ; 4877(2): zootaxa.4877.2.4, 2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-33311190

RESUMEN

The Einasleigh Uplands bioregion of central north Queensland, Australia, harbours a unique suite of reptiles that have begun to receive significant attention in the last 20 years. This has resulted in a number of new reptile species being described, and recognition that others await description. We describe a new species of Lucasium Wermuth, 1965 from the western Einasleigh Uplands. Lucasium iris sp. nov. is genetically distinct and morphologically diagnosable from all congeners by its large size, long and narrow tail, nares in contact with rostral scale, homogeneous body scales, distinct vertebral stripe, and paired, enlarged, apical subdigital lamellae. It is known from low rocky hills in a localised area of the Gregory Range, has the most restricted known distribution of any Lucasium, and is the only Lucasium endemic to Queensland. The new species appears most closely related to L. steindachneri (Boulenger, 1885), based on mitochondrial DNA sequences, but has a colour-pattern more similar to L. immaculatum Storr, 1988. All three of these species occur in the Einasleigh Uplands, but only L. steindachneri is known to occur in sympatry with L. iris sp. nov. In addition to the description of the new species, we present records of Lucasium immaculatum from the Einasleigh Uplands, which represent a significant known range extension.


Asunto(s)
Lagartos , Distribución Animal , Animales , Australia , Ecosistema , Queensland
7.
Zootaxa ; 4688(4): zootaxa.4688.4.3, 2019 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-31719426

RESUMEN

We describe a new species of rock-dwelling Gehyra Gray, 1834 (Gekkonidae) from the Einasleigh Uplands of inland north Queensland, Australia. Morphological, ecological, and molecular data clearly support the new species as distinct and place it within the 'australis group'. Gehyra electrum sp. nov. is distinguished from congeners by a combination of medium adult size (SVL 46-50 mm), an orange-brown to pinkish-orange background colouration with a pattern of distinct whitish spots and irregular black to purple-brown blotches or bars, possessing 7-8 undivided subdigital lamellae on the expanded portion of the fourth toe, and a wedge-shaped mental scale that separates the inner-postmental scales along 40% or more of their length. Gehyra electrum sp. nov. is a rock specialist currently known only from granite outcrops of the Mt Surprise region, Queensland. This is the second recently described Gehyra from the Einasleigh Uplands and adds to the growing number of endemic reptiles recognised in the region.


Asunto(s)
Lagartos , Distribución Animal , Estructuras Animales , Animales , Australia , Tamaño Corporal , Ecosistema , Queensland
8.
Zootaxa ; 4577(3): zootaxa.4577.3.3, 2019 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-31715709

RESUMEN

Ongoing surveys for skinks of the genus Lerista in north Queensland have resulted in the collection of voucher specimens from two populations formerly assigned to Lerista storri Greer, McDonald Lawrie, 1983 that are geographically isolated from the type population and show a degree of morphological variation differing from the type population. Analysis of recently collected material has confirmed both populations are specifically distinct to the type population, with one being more closely related to Lerista ameles Greer, 1979, another little known, north Queensland species. Consequently, these populations are described as Lerista alia sp. nov. and Lerista parameles sp. nov. The morphological diversity of L. storri is thereby restricted, necessitating a redescription. The conservation status of all these taxa is discussed.


Asunto(s)
Gastrópodos , Lagartos , Animales , Queensland
9.
Zootaxa ; 4231(1): zootaxa.4231.1.5, 2017 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-28187551

RESUMEN

The tropical savannah landscapes of Australia's north, though previously overshadowed by the biodiverse rainforests of the Wet Tropics, are themselves now attracting interest for their biological significance and uniqueness. The Einasleigh Uplands region of north-east Queensland is home to a diverse group of mammals and reptiles and was previously recognised for its importance in shaping speciation in birds. Here we add a small saxicoline gecko to a growing list of recently described reptiles that are endemic to this region. Phylogenetic analyses including Gehyra species from the arid zone and the monsoonal tropics reveal that small Gehyra geckos in this area, while closely resembling Gehyra nana from the Top End and Kimberley, form a clade that is geographically isolated and phylogenetically distant from the G. nana complex. Instead, the Einasleigh Uplands taxon is sister to a large, arboreal species within the arid zone clade. It is readily distinguished from all lineages within the G. nana complex, its closest relative G. purpurascens, and all other rock-dwelling species from the arid zone by a combination of its very small body size, few subdigital lamellae, and mid tan to golden dorsal coloration with a pattern of scattered pale ocelli and irregular dark-brown blotches on a stippled background. We therefore describe this taxon as a new Australian species of Gehyra, Gehyra einasleighensis sp. nov., based on a combination of phylogenetic separation, morphological characters and discrete geographic distribution.


Asunto(s)
Lagartos , Animales , Australia , Tamaño Corporal , Femenino , Filogenia , Queensland
10.
Front Plant Sci ; 7: 1008, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27471508

RESUMEN

Traditional agriculture in rainfed uplands of India has been experiencing low agricultural productivity as the lands suffer from poor soil fertility, susceptibility to water erosion and other external pressures of development and climate change. A shift toward more sustainable cropping systems such as conservation agriculture production systems (CAPSs) may help in maintaining soil quality as well as improving crop production and farmer's net economic benefit. This research assessed the effects over 3 years (2011-2014) of reduced tillage, intercropping, and cover cropping practices customized for maize-based production systems in upland areas of Odisha, India. The study focused on crop yield, system productivity and profitability through maize equivalent yield and dominance analysis. Results showed that maize grain yield did not differ significantly over time or among CAPS treatments while cowpea yield was considered as an additional yield in intercropping systems. Mustard and horsegram grown in plots after maize cowpea intercropping recorded higher grain yields of 25 and 37%, respectively, as compared to those without intercropping. Overall, the full CAPS implementation, i.e., minimum tillage, maize-cowpea intercropping and mustard residue retention had significantly higher system productivity and net benefits than traditional farmer practices, i.e., conventional tillage, sole maize cropping, and no mustard residue retention. The dominance analysis demonstrated increasing benefits of combining conservation practices that exceeded thresholds for farmer adoption. Given the use of familiar crops and technologies and the magnitude of yield and income improvements, these types of CAPS should be acceptable and attractive for smallholder farmers in the area. This in turn should support a move toward sustainable intensification of crop production to meet future household income and nutritional needs.

11.
Remote Sens Ecol Conserv ; 2(4): 212-231, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31423326

RESUMEN

Uplands represent unique landscapes that provide a range of vital benefits to society, but are under increasing pressure from the management needs of a diverse number of stakeholders (e.g. farmers, conservationists, foresters, government agencies and recreational users). Mapping the spatial distribution of upland vegetation could benefit management and conservation programmes and allow for the impacts of environmental change (natural and anthropogenic) in these areas to be reliably estimated. The aim of this study was to evaluate the use of medium spatial resolution optical and radar satellite data, together with ancillary soil and topographic data, for identifying and mapping upland vegetation using the Random Forests (RF) algorithm. Intensive field survey data collected at three study sites in Ireland as part of the National Parks and Wildlife Service (NPWS) funded survey of upland habitats was used in the calibration and validation of different RF models. Eight different datasets were analysed for each site to compare the change in classification accuracy depending on the input variables. The overall accuracy values varied from 59.8% to 94.3% across the three study locations and the inclusion of ancillary datasets containing information on the soil and elevation further improved the classification accuracies (between 5 and 27%, depending on the input classification dataset). The classification results were consistent across the three different study areas, confirming the applicability of the approach under different environmental contexts.

12.
J Appl Ecol ; 49(4): 941-952, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32367892

RESUMEN

1. Wetlands are ecologically and economically important ecosystems but are threatened globally by many forms of human disturbance. Understanding the responses of wetland species to human disturbance is essential for effective wetland management and conservation. 2. We undertook a study to determine (i) whether anurans can be used effectively to assess the ecological integrity of wetlands affected by groundwater withdrawal and, if so, (ii) what effect increasing urbanization might have on the utility of anurans as wetland indicators. We monitored the intensity of anuran calls at 42 wetlands in south-western Florida throughout 2001-2002 and 2005-2009. 3. We first validated the use of anurans to assess wetland integrity using a small group of wetlands by comparing anuran calling and subsequent tadpole development with an established index employing vegetation composition and structure. We then verified that the results could be expanded to a variety of sites throughout the region. Finally, we focused on urbanized wetlands to determine whether urbanization could interfere with the use of anurans to assess wetland integrity. 4. We used PRESENCE to estimate occupancy and detection probabilities and to examine the relationship between occupancy and five covariates expected to influence individual species occurrence. We used FRAGSTATS to calculate the mean proximity index for urbanized wetlands, which assesses the size and distribution of land use types within a specified area. 5. Our results showed that the group of species including oak toad Anaxyrus quercicus, southern cricket frog Acris gryllus, pinewoods treefrog Hyla femoralis, barking treefrog Hyla gratiosa, and little grass frog Pseudacris ocularis is a reliable indicator of wetland integrity. However, this same group of species, which is sensitive to wetland health, is selectively excluded from urbanized wetlands. 6. Synthesis and applications. Although anurans are effective indicators of wetland health and complement vegetation surveys, the usefulness of this group for monitoring the ecological integrity of wetlands can be substantially reduced, or eliminated, as a consequence of urbanization. We urge for careful consideration of confounding factors in any studies examining the utility of indicator species.

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