Treesearch

Description: This paper takes a social constructionist approach to examine the nature and dynamics of personal and social meanings of wilderness. The paper builds on geographic and social theory to discuss the ways in which conflicts over the meaning and value of wilderness are significant consequences of modernization and globalization. The process of modernization destabilizes and “thins out” the meanings assigned to places and undermines older, more traditional meanings. While such social constructionist views of wilderness and nature are sometimes seen as undermining protectionist...

Stemwood and understory production (kg ha-1) were estimated during 3 nonconsecutive years on 5 growing stock levels of ponderosa pine including clearcuts and unthinned stands. Stemwood production was consistently greater at mid- and higher pine stocking levels, and understory production was greater in stands with less pine; however, there were no differences in total (stemwood + understory) production. Based on loss of productivity, there is no argument that small clearcuts and unthinned stands should not be included in site plans. They contribute significantly to community structure,...

Age classes of migrant songbirds often differ in migration timing. This difference creates the potential for age-ratios recorded at stopover sites to vary with the amount and distribution of sampling effort used. To test for these biases, we sub-sampled migrant capture data from the Middle Rio Grande Valley of New Mexico. We created data sets that reflected the age ratios of migrants that would have been captured with stratified and concentrated designs at four levels of mist-netting effort. Analysis of these data indicate that age-ratios of Neotropical migrants varied significantly with...

Differential fractionation of stable isotopes of carbon during photosynthesis causes C4 plants and C3 plants to have distinct carbon-isotope signatures. In addition, marine C3 plants have stable-isotope ratios of carbon that are intermediate between C4 and terrestrial C3 plants. The direct incorporation of the carbon-isotope ratio (13C/12C) of plants into consumers' tissues makes this ratio useful in studies of animal ecology. The heavy isotope of nitrogen (15N) is preferentially incorporated into the tissues of the consumer from the diet, which results in a systematic enrichment in...

Banner-tailed kangaroo rats (Dipodomys spectabilis) are prominent ecosystem engineers that build large mounds that influence the spatial structuring of fungi, plants, and some ground-dwelling animals. Ants are diverse and functionally important components of arid ecosystems; some species are also ecosystem engineers. We investigated the effects of patch disturbances created by D. spectabilis mounds on ant assemblages in a Chihuahuan Desert grassland in southern New Mexico by using pitfall traps in a paired design (mound vs. matrix). Although the disturbances did not alter species richness...

The Central Arizona Highlands are a distinct biogeographic, climatic, and physiographic province that forms a diverse ecotone between the larger Colorado Plateau to the north and the Sonoran Desert ecoregions to the south (figure 1). The Highlands coincide approximately with the Arizona Transition Zone identified by ecologists, geologists and others. This region is one of the last in the Southwestern United States that was settled by European immigrants.

Water has been recognized as an important resource in central Arizona and has affected populations occupying the Salt River Valley for centuries. Water related activities have been documented since about 200 before the common era, when Hohokam Indians settled the Valley and constructed canals to irrigate their fields. Europeans began to settle in the Phoenix area in the late 1860s and depended on irrigation water from the Salt River for agriculture. However, water supplies fluctuated greatly because the river often flooded in winter and dried up in the summer. There were no impoundments to...

Yavapai County in central Arizona supports extensive stands of chaparral in the Bradshaw Mountains, Mingus Mountain, and the Santa Maria Range. Chaparral occupies about 400,300 acres of the Prescott National Forest (Anderson 1986). These chaparral communities provide a wide range of benefits including watershed protection, grazing for wildlife and domestic animals, recreational opportunities, and wildlife habitat. As in other chaparral areas in Arizona and California, these shrublands are subject to regular wildfires that can destroy the protective shrub canopy and leave the burned areas...

The amount of water stored in the Salt River Project reservoirs during the middle 1950s was low and, as a consequence, apprehension arose among some residents of the Salt River Valley that a serious water shortage would soon occur. Groundwater supplies in the Valley were also being rapidly depleted, and pumping costs were steadily rising. Long-term studies at Sierra Ancha Experimental Forest had shown some potential for increasing runoff by converting chaparral shrublands to grass (Gottfried et al., Chapter 2 of this publication). Therefore, a belief existed that the yield of water from...

Higher mountains and plateaus in the Central Arizona Highlands generally support southwestern mixed conifer forests, associated aspen and spruce-fir forests, and a small acreage of grasslands interspersed among the forested areas. Most of the major rivers in the region originate on headwater watersheds that support mixed conifer forests where annual precipitation, particularly snow, is high and evapotranspiration demands are lower than other vegetation types in the Central Arizona Highlands. Rich and Thompson (1974) reported that 6% of Arizona's surface water originates from the portion of...