نتایج جستجو برای: dalab woodlands
تعداد نتایج: 1978 فیلتر نتایج به سال:
• California coastal woodlands are suffering severe disease and mortality as a result of infection from Phytophthora ramorum . Quercus agrifolia is one of the major woodland species at risk. This study investigated withinand among-population variation in host susceptibility to inoculation with P. ramorum and compared this with population genetic structure using molecular markers. • Susceptibili...
We examined population trends and factors related to the abundance and presence of European starlings (Sturnus vulgaris) at the San Joaquin Experimental Range in the foothills of the western Sierra Nevada, 31 km east of Madera, California. Starlings first appeared there in low numbers in the late 1960s and are now abundant breeders. Simple models examining trends in starling numbers and presenc...
Taxonomic homogenization (TH) is the increasing similarity of the species composition of ecological communities over time. Such homogenization represents a form of biodiversity loss and can result from local species turnover. Evidence for TH is limited, reflecting a lack of suitable historical datasets, and previous analyses have generated contrasting conclusions. We present an analysis of wood...
Quick biodiversity studies on poorly studied taxa and areas are increasingly popular for setting conservation priorities over a wide range of spatial scales. However, the implementation of such studies is complicated by the variable extent to which the different criteria used in prioritisation are correlated to each other. Using methods of constrained ordination, we examined the specieshabitat ...
The period between the culmination of the South African War in May 1902 and the Union of South Africa eight years later witnessed a significant phase in the development of the Cape’s Forestry Department. The Colony’s scientific foresters articulated a rhetoric of crisis, based on the assumption that global timber supplies were almost exhausted, in order to encourage politicians to take action t...
Modeled Shifts in Polylepis Species Ranges in the Andes from the Last Glacial Maximum to the Present
Polylepis woodlands, the dominant high-elevation woodland species of the Andes of South America, are an increasingly important focus of conservation and restoration efforts as a buffer to the regional effects of climate change. However, the natural extent of these woodlands before the arrival of human populations is still debated. One significant approach to this question is an assessment of th...
Understanding which flowers honey bees (Apis mellifera) use for forage can help us to provide suitable plants for healthy honey bee colonies. Accordingly, honey DNA metabarcoding provides a valuable tool for investigating pollen and nectar collection. We investigated early season (April and May) floral choice by honey bees provided with a very high diversity of flowering plants within the Natio...
People value proximity and easy access to protected areas in urban landscapes, including state and regional parks, wildlife refuges, and open space preserves. The popularity of outdoor recreation activities such as hiking and birdwatching has more than doubled in the past 20 years, and surveys indicate that proximity to natural areas is an important factor determining where residents choose to ...
Conservation Reserve Program Conservation Practice 33 (CP33: Conservation Buffers for Upland Birds) provides habitat for grassland birds in agriculture-dominated landscapes. However, landscape context and adjacency of other land covers may influence colonization, occupancy, and reproductive performance of breeding grassland birds in buffers. Our objective was to determine how edge effects influ...
Acute Oak Decline (AOD) is a new condition affecting both species of native oak, Quercus robur and Quercus petraea, in Great Britain. The decline is characterised by a distinctive set of externally visible stem symptoms; bark cracks that “weep” dark exudate are found above necrotic lesions in the inner bark. Emergence holes of the buprestid beetle, Agrilus biguttatus are often also seen on the ...
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