Treesearch

This work focuses on identifying deforestation patterns and relating these to social processes in an extractive reserve of Acre (western Amazonia). Using multitemporal satellite imagery deforestation is observed as a series of distinctive patches against the background of forest cover. The study of patterns emphasizes the important relationships existing between spatial patterns and social and spatially explicit processes. Since human processes are scale-dependant, a series of indexes were used to assess the structure, function, and change of the spatial distribution of patches at two...

Wildfires in the Middle Rio Grande bosque have likely increased in frequency due to absence of the natural flood regime and current drought conditions. Native cottonwoods (Populus spp.) do not tolerate or recover from wildfire as well as exotic vegetation, particularly salt cedar, also known as tamarisk (Tamarix spp.). There is concern that this change in the primary disturbance process from flood to fire will shift vegetative succession away from structurally diverse mesic native communities to structurally simple xeric exotic shrub-lands, which provide inferior habitat for ripariandepende...

The endangered Southwestern Willow Flycatcher (Empidonax traillii extimus: SWWF) is a riparian-obligate bird that breeds only in dense, typically wet riparian vegetation. Since the mid-1990s, biologists have discovered a substantial number of flycatchers breeding in habitat dominated by exotic saltcedar (Tamarix ramossisima) in sites across Arizona, New Mexico, Nevada, and Utah. Today, approximately 25 percent of SWWF breeding sites, supporting one-third of the roughly 1,300 known flycatcher territories, are in saltcedar-dominated sites. A widely held belief is that this saltcedar habitat...

The identification of conservation priorities is one of the leading issues in conservation biology. We present a project of The Nature Conservancy, called Sequencing Conservation Actions, which prioritizes conservation areas and identifies foci for crosscutting strategies at various geographic scales. We use the term “Sequencing” to mean an ordering of actions over time and “Conservation Actions” to represent strategies implemented both at and across conservation areas, and from local to global scales. There are three outcomes of the Sequencing Project. The first is the ranking of conservat...

The general principles of scale and coarse and fine filters have been widely accepted, but management agencies and industry are still grappling with the question of what to monitor to detect changes in forest biodiversity after forest management. Part of this problem can be attributed to the lack of focused questions for monitoring associated with an absence of null models and predicted effects, a certain level of disconnect between research and management, and recognition that, in the case of forest management, monitoring is research. Considerable research from the past decade has not...

Tamarisk is a woody invasive weed of riparian areas which has galvanized an amazing array of scientists, politicians, ranchers, farmers, tribal people, and many other interested parties because of its devastating impacts on natural ecosystems and valuable water ways in the west. Rarely has a single plant become such a catalyst for so many people to use as a “poster child” for a variety of interesting issues. Among these issues are water resource issues, soil quality, land use issues, wildlife habitats, access to federal funds to support local community initiatives, and support for research...

The Environmental Protection Agency (EPA) designed the Environmental Monitoring and Assessment Program (EMAP) to provide tools to monitor and assess the condition of the nation’s ecological resources. Since 1993, EPA Region 10 has worked with the States in our region to demonstrate the application of the ecological indicators and statistical designs developed by EMAP to freshwater and marine assessments. To illustrate the types of assessment questions that can be addressed with EMAP data, we present an example study of the Western Cascades Ecoregion of Oregon and Washington. In 1999-2000,...

Riparian vegetation buffer loss was investigated for three cities with contrasting local regulatory controls in urbanizing northwest Oregon. The cities examined were Hillsboro, Oregon City and Portland, all having experienced high rates of population increase in the 1990s. All cities are covered under Oregon’s land use law that provides goals for the protection of open space and natural resources. On the municipality level, regulatory controls in Portland included a system of environmental zoning for riparian area protection, while regulatory controls on development in riparian areas in...

The results of a biodiversity monitoring program conducted in the Ogawa Forest Reserve and its vicinity, situated in a temperate region of Japan, identified three different patterns for species richness. Forests of the region are characterized by a mosaic of secondary deciduous stands of various ages scattered among plantations of conifers. The three different types of change in species richness observed in response to the stand age are as follows: 1. Type I (butterflies, tube-renting bees and wasps, hoverflies, fruit flies, and longicorn beetles), the species diversity was highest in open...

Trees in cities can contribute significantly to human health and environmental quality. Unfortunately, little is known about the urban forest resource and what it contributes to the local, regional, and national societal and economic interests. To help better understand the urban forest resource and its numerous values, the USDA Forest Service has initiated a pilot program to sample urban forests and street tree populations across various states. Pilot tests of monitoring the total tree population in urban areas have been or are being conducted in Indiana, Wisconsin, and New Jersey. Pilot...