Treesearch

Tropical infectious disease prevalence is dependent on many socio-cultural determinants. However, rainfall and temperature frequently underlie overall prevalence, particularly for vector-borne diseases. As a result these diseases have increased prevalence in tropical as compared to temperate regions. Specific to tropical Africa, the tendency to incorrectly infer that tropical diseases are uniformly prevalent has been partially overcome with solid epidemiologic data. This finer resolution data is important in multiple contexts, including understanding risk, predictive value in disease...

We report the long-distance dispersal of a subadult male cougar (Puma concolor) from South Dakota to Milford, Connecticut, where it was struck and killed by a vehicle. Genetic samples suggest this animal originated from the Black Hills of South Dakota while isotope analysis and physical inspection revealed no evidence that the animal had been held in captivity. We detected this dispersing individual at 5 locations along its route (Minnesota, 3 times in Wisconsin and New York) with DNA from fecal or hair samples, and with multiple photographs from citizen-run camera traps (3 in Wisconsin...

Increases in wildfire occurrence and severity under an altered climate can substantially impact terrestrial ecosystems through enhancing runoff erosion. Improved prediction tools that provide high resolution spatial information are necessary for location-specific soil conservation and watershed management. However, quantifying the magnitude of soil erosion and its interactions with climate, hydrological processes, and fire occurrences across a large region (>10,000 km2) is challenging because of the large computational requirements needed to capture the fine-scale complexities of the land...

The 2000 Valley Complex wildfire burned in steep montane forests with ash cap soils in western Montana, USA. The effects of high soil burn severity on forest soil hydrologic function were examined using rainfall simulations (100mmh-1 for 1 h) on 0.5-m2 plots. Infiltration rates, sediment yields and sediment concentrations were compared among three treatments: control (unburned and undisturbed); bare (unburned with all surface vegetation, litter, and duff removed prior to each simulation); and burned. Rainfall simulations were done immediately after the fire and repeated in 2001, 2002, and...

Post-fire increases of runoff and erosion often occur and land managers need tools to be able to project the increased risk. The Erosion Risk Management Tool (ERMiT) uses the Water Erosion Prediction Project (WEPP) model as the underlying processor. ERMiT predicts the probability of a given amount of hillslope sediment delivery from a single rainfall or snowmelt event on unburned, burned and recovering forest, range and chaparral hillslopes and the effectiveness of selected mitigation treatments. Eight published field study sites were used to compare ERMiT predictions with observed...

Advances in research into wildfire impacts on runoff and erosion have demonstrated increasing complexity of controlling factors and responses, which, combined with changing fire frequency, present challenges for modellers. We convened a conference attended by experts and practitioners in post-wildfire impacts, meteorology and related research, including modelling, to focus on priority research issues. The aim was to improve our understanding of controls and responses and the predictive capabilities of models. This conference led to the eight selected papers in this special issue. They...

Hydrologic response to rainfall on fragmented or burnt hillslopes is strongly influenced by the ensuing connectivity of runoff and erosion processes. Yet cross-scale process connectivity is seldom evaluated in field studies owing to scale limitations in experimental design. This study quantified surface susceptibility and hydrologic response across point to hillslope scales at two degraded unburnt and burnt woodland sites using rainfall simulation and hydrologic modelling. High runoff (31-47 mm) and erosion (154-1893 g m -2) measured at the patch scale (13 m2) were associated with accumulat...

The purpose of this paper is to recommend a framework and methodology for incorporating hydrologic data and ecohydrologic relationships in Ecological Site Descriptions (ESDs) and thereby enhance the utility of ESDs for assessing rangelands and guiding resilience-based management strategies. Resilience-based strategies assess and manage ecological state dynamics that affect state vulnerability and, therefore, provide opportunities to adapt management. Many rangelands are spatially heterogeneous or sparsely vegetated where the vegetation structure strongly influences infiltration and soil...

Armillaria root diseases are among the most damaging and broadly distributed group of forest diseases in the world (Lockman et al. in press). Armillaria root disease is typically more severe in highly susceptible tree species and in trees that are maladapted due to rapidly changing climatic conditions (Ayres and Lombardero 2000, Kliejunas et al. 2009, Sturrock et al. 2011). Unfortunately, Armillaria root disease is notoriously difficult to manage in forests. Because Armillaria root disease impacts are dependent on complex ecological interactions among the host, soil microbial community,...

Raffaelea quercus-mongolicae is a fungus associated with oak wilt and deemed to cause extensive oak mortality in South Korea. Since the discovery of this fungus on a dead Mongolian oak (Quercus mongolica) in 2004, the mortality continued to spread southwards in South Korea. Despite continued expansion of the disease and associated significant impacts on forest ecosystems, information is lacking about the origin and genetic diversity of R. quercus-mongolicae. Restriction-site-associated DNA (RAD) sequencing was used to assess genetic diversity and population structure among five populations...