Treesearch

In Nordamerika sind Wälder infolge von Einwandernden, internationalem Handel und Tourismus traditionell stark von Einschleppungen gebietsfremder invasiver Schadorganismen betroffen. Infolge von Globalisierung und Klimawandel gibt es aufgrund der Ähnlichkeiten von Klima, Flora und Fauna zwischen Europa und Nordamerika viele Parallelen.

Despite the mental and physical benefits of visiting natural areas, and increases in outdoor activity participation among U.S. youth overall in the past decade, outdoor access is skewed toward nonurban, nonminority populations. This environmental justice issue is particularly pronounced for minority youth in urban areas, such as the Los Angeles Basin. While decreased contact with nature has been associated with increased technology use, the popularity of new technologies and social media outlets presents novel opportunities to connect underserved urban youth with natural areas. Seven focus...

Soil moisture varies within landscapes in response to vegetative, physiographic, and climatic drivers, which makes quantifying soil moisture over time and space difficult. Nevertheless, understanding soil moisture dynamics for different ecosystems is critical, as the amount of water in a soil determines a myriad ecosystem services and processes such as net primary productivity, runoff, microbial decomposition, and soil fertility. We investigated the patterns and variability in in situ soil moisture measurements converted to plant‐available water across time and space under different...

Drought has the ability to affect the persistence of small animal populations, especially those tied to aquatic habitats. We studied the response of western pond turtles Actinemys marmorata to California's worst drought on record. From 2009 through 2015 we used telemetry to track movements and assess survival of 19 western pond turtles in a stock pond at the San Joaquin Experimental Range in the western foothills of the Sierra Nevada, in Madera County, California. In 2013 the pond dried in late summer and winter rains were insufficient for pond formation. The pond remained dry through the...

The California spotted owl (Strix occidentalis occidentalis) is a species of conservation concern owing to threats to its habitat and populations. Verner et al. (1992) first assessed the status of the California spotted owl "The California Spotted Owl: A technical Assessment of it’s current status" (CASPO) and identified four factors as either threats or potential threats to the viability of California spotted owl populations: (1) timber harvest and forest management, (2) wildfire, (3) development of gaps in owl distribution across the Sierra Nevada, and (4) human population growth and...

Spotted owl populations found in southern and central coastal California have received much less attention than those inhabiting the Sierra Nevada because of economic (effect of habitat conservation measures on timber harvest) and social issues (community stability and desire for naturally functioning ecosystems). Yet there has been continued concern over the status of owl populations in this region since the first technical assessment of the California spotted owl "The California Spotted Owl: A Technical Assessment of Its Current Status" (CASPO) in 1992 (Eliason and Loe 2011,2 LaHaye and...

In this chapter, we synthesize the information presented in the preceding chapters of this assessment of the California spotted owl (Strix occidentalis occidentalis) and provide a scientific appraisal of its implications for forest management and owl conservation. We focus on the key scientific findings since the 1992 California spotted owl technical assessment (CASPO) (Verner et. al. 1992) and discuss priorities for future research that could enhance the successful conservation of California spotted owls and their habitat. Throughout this chapter, we acknowledge when uncertainty limits...

The purpose of this work is to estimate willingness to pay (WTP) for minority (African-American and Hispanic) homeowners in Florida for private and public wildfire risk-reduction programs and also to test for differences in response between the two groups. A random parameter logit and latent class model allowed us to determine if there is a difference in wildfire mitigation program preferences, whether WTP is higher for public or private actions for wildfire risk reduction, and whether households with personal experience and who perceive that they live in higher-risk areas have significantl...

Rainfall interception research in forest ecosystems usually focuses on interception by either tree crown or leaf litter, although the 2 components interact when rainfall occurs. A process-based study was conducted to jointly measure rainfall interception by crown and litter and the interaction between the 2 interception processes for 4 tree species (Platycladus orientalis and Pinus tabulaeformis represented needle-leaf species, and Quercus variabilis and Acer truncatum represented broadleaf species) at 3 simulated rainfall intensities (10, 50, and 100 mm hr−1). Results indicated that (a)...

Urban forests can be an effective strategy for managing stormwater. The soil that supports tree growth acts like a reservoir that reduces runoff. The tree crown intercepts rainfall on leaves and stems and its evaporation reduces water reaching the ground below. Until now surface storage capacities have been studied only for forest trees. Based on forest research, green infrastructure accounting tools have assumed a storage depth of one millimeter, regardless of species. We used a rainfall simulator and branch cuttings of 20 tree species in Davis, CA to measure the depth of surface storage...