Treesearch

The Puerto Rico Breeding Bird Atlas (PRBBA) project collected and summarized information on the timing of breeding and geographic distribution of 130 breeding bird species on Puerto Rico, and its associated satellite islands and cays. Fieldwork coordinated by the Puerto Rican Ornithological Society (SOPI) involved 344 volunteer observers who contributed to more than 45,500 individual observations of birds from 2004 through 2009. Following standard breeding bird atlas protocol, observers searched for breeding evidence in 479 hexagons while recording bird behavior. Each observed behavior was...

More people visit public lands for recreation than for any other reason, which makes providing opportunities for sustainable recreation a key service that national forests can provide. Recreation managers, however, frequently lack basic information on the amount and extent of recreation use. Traditional approaches that rely on visitor traffic counts and in-person interviews to measure visits and recreation can be costly and may not provide needed information in a timely way.A team of scientists with the USDA Forest Service, Pacific Northwest Research Station and the University of Washington...

Soil organic carbon (SOC) is a major indicator of soil health. Globally, soil contains approximately 2344 Gt of organic carbon (OC), which is the largest ter-restrial pool of OC. Through plant growth, soil health is connected with the health of humans, animals, and ecosystems. Provides ecosystem services which include climate regulation, water supplies and regulation, nutrient cycling, erosion protection and enhancement of biodiversity. Global increase in land use change from natural vegetation to agricultural land has been documented as a result of intensification of agricultural practices...

The oomycete Aphanomyces astaci is an emerging infectious pathogen affecting freshwater crayfishworldwide and is responsible for one of the most severe wildlife pandemics ever reported. Thepathogen has caused mass mortalities of freshwater crayfish species in Europe and Asia, and threatensother susceptible species in Madagascar, Oceania and South America. The pathogen naturally coexistswith some North American crayfish species that are its chronic carriers. Presumptions that A. astacioriginated in North America are based on disease outbreaks that followed translocations of NorthAmerican...

Tropical savanna ecosystems play a major role in the seasonality of the global carbon cycle. However, their ability to store and sequester carbon is uncertain due to combined and intermingling effects of anthropogenic activities and climate change, which impact wildfire regimes and vegetation dynamics. Accurate measurements of tropical savanna vegetation aboveground biomass (AGB) over broad spatial scales are crucial to achieve effective carbon emission mitigation strategies. UAV-lidar is a new remote sensing technology that can enable rapid 3-D mapping of structure and related AGB in...

Extreme wildfires are a major environmental and socioeconomic threat across many regions worldwide. The limits of fire suppression-centred strategies have become evident even in technologically well-equipped countries, due to high-cost and a legacy of landscape transformations, yet with ultimately low-efficient solutions vis- `a-vis extreme fires. Many practitioners and policymakers thus increasingly recognize the need to develop novel, integrated fire management approaches that shift emphasis towards the root causes of extreme fires. Here we provide from the socioeconomic angle a collectiv...

In forest canopies, it is common to perform leaf-level gas-exchange measurements on recently excised branches, often without testing for excision-related biases. We conducted a formal test of excision effects using gas-exchange measurements from cut and uncut canopy branches of three deciduous hardwoods – sugar maple (Acer saccharum Marsh.), tulip poplar (Liriodendron tulipifera L.), and white oak (Quercus alba L.). Across all species, excision immediately reduced photosynthesis and stomatal conductance by 27–62% relative to pre-excision rates. In white oak, which had particularly long (>...

Black ash (Fraxinus nigra) wetlands are widespread, forested landscape features in the western Great Lakes region. However, the future of these ecosystems is threatened due to impending spread of the invasive emerald ash borer (EAB), which results in tree mortality, decreased transpiration, and potential shifts to wetter, non-forested conditions. The vulnerability to such ecohydrologic shifts likely varies according to local hydrologic regimes controlled by landscape settings, but this site-dependent vulnerability and our ability to predict it is unknown. Here, we assessed vulnerability...

Specific heat capacity of eleven live foliar fuels from the southeastern United States was measured to 434 ◦C using differential scanning calorimetry to improve the modeling of prescribed fire behavior. Techniques which allow measurement of the standard heat capacity, excluding the effects of heat of reaction, were refined. Specific heat of leaves increased with temperature until the onset of pyrolysis. Once pyrolysis began, the specific heat became nearly constant. We present a simple model, suitable for incorporation in computer simulations, which captures this functional shape. This...

Community-based forest management has become increasingly widespread in Africa since the 1990s as an approach to conserving local forests while contributing social and economic benefits to local communities. Community forests (CFs) can sell forest goods and services to generate revenue for community benefit. Increased understanding of whether and how CFs can be economically viable is important for assessing their potential to alleviate rural poverty and deliver benefits to local communities. Questions of viability of commercial timber-producing CFs largely have not been addressed to date...