Treesearch

Epigenetic modifications of chromatin structure are extremely important in mediating stress responses in plants. Epigenetic modifications are especially important in perennial species such as trees, where they contribute to phenotypic plasticity and adaptation to unfavourable environments. Populusis a model for physiological studies of trees, and is suitable for phytoremediation of Zn-contaminated soils. Currently, epigenetic modifications involved in Zn stress response are poorly characterized for Populus. Here, we compared changes in epigenetic modifications under excess Zn using...

Concealment behavior by stream salmonids can benefit individuals and populations, but the availability of concealment habitat may be limited in many streams. Quantification of concealment habitat is likely to be a valuable process in the management of stream salmonids; it is a necessary step in the application of spatially explicit, individual‐based models that incorporate concealment behavior. We conducted a series of laboratory experiments with Rainbow Trout Oncorhynchus mykissto aid in the identification and quantification of concealment habitat. Overall, individual Rainbow Trout about...

Globally, mangrove forests represents only 0.7% of world's tropical forested area but are highly threatened due to susceptibility to climate change, sea level rise, and increasing pressures from human population growth in coastal regions. Our study was carried out in the Bhitarkanika Conservation Area (BCA), the second‐largest mangrove area in eastern India. We assessed total ecosystem carbon (C) stocks at four land use types representing varying degree of disturbances. Ranked in order of increasing impacts, these sites included dense mangrove forests, scrub mangroves, restored/planted...

This document provides a summary of the current state of knowledge regarding Ceratocystis-induced Rapid Ohia Death and an initial presentation and analysis of the options to manage the disease. It also provides essential background information for use in development and refinement of a response plan.

Large trees are important to a wide variety of wildlife, including many species of conservation concern, such as the California spotted owl (Strix occidentalis occidentalis). Light detection and ranging (LiDAR) has been successfully utilized to identify the density of large-diameter trees, either by segmenting the LiDAR point cloud into individual trees, or by building regression models between variables extracted from the LiDAR point cloud and field data. Neither of these methods is easily accessible for most land managers due to the reliance on specialized software, and much available...

Treatments to reduce forest fuels are often performed in forests to enhance forest health, regulate stand density, and reduce the risk of wildfires. Although commonly employed, there are concerns that these forest fuel treatments (FTs) may have negative impacts on certain wildlife species. Often FTs are planned across large landscapes, but the actual treatment extents can differ from the planned extents due to operational constraints and protection of resources (e.g. perennial streams, cultural resources, wildlife habitats). Identifying the actual extent of the treated areas is of primary...

Pests or pathogens that affect trees have the potential to fundamentally alter forest composition, structure and function. Throughout the last six years, large areas of otherwise healthy ‘ōhi‘a (Metrosideros polymorpha) trees have been dying rapidly (typically within weeks) in lowland tropical wet forest on Hawai‘i Island, USA. This mortality is quite distinct from previous well-documented ‘ōhi‘a dieback episodes driven by cohort senescence. Ceratocystis fimbiata was identified and routinely found associated with rapidly dying individuals of ‘ōhi‘a, Hawai‘i’s most widespread native tree....

Background: Spatially explicit forest carbon (C) monitoring aids conservation and climate change mitigation eforts, yet few approaches have been developed specifcally for the highly heterogeneous landscapes of oceanic island chains that continue to undergo rapid and extensive forest C change. We developed an approach for rapid mapping of aboveground C density (ACD; units = Mg or metric tons C ha−1) on islands at a spatial resolution of 30 m (0.09 ha) using a combination of cost-efective airborne LiDAR data and full-coverage satellite data. We used the approach to map forest ACD across the...

Monitoring studies often use marked animals to estimate population abundance at small spatial scales. However, at smaller scales, occupancy sampling, which uses detection/nondetection data, may be useful where sites are approximately territories, and occupancy dynamics should be strongly correlated with population dynamics. Occupancy monitoring has advantages in that it is less expensive and invasive, and marked animals are not needed. Here, we used empirical data to determine whether and when change in occupancy is a good proxy for population change for a territorial species. As part of...

The use of spring prescribed fires to reduce accumulated fuel loads in western forests and facilitate the return of natural fire regimes is a controversial topic. While spring burns can be effective at reducing fuel loads and restoring heterogeneous landscapes, concerns exist over the potential impacts of unnaturally-timed fires to native species. To protect native wildlife from disturbance during critical periods, limited operating periods (LOPs) are often implemented. However when LOPs for multiple species are combined into an integrated management plan, very few time windows for...