Treesearch

Flying across the eastern United States at an altitude of 10,000 m, we see a landscape below that is a mosaic of forests, rivers, farm fields, towns, and cities. Almost all of the lands covered by forests today have undergone intensive harvest, and even regrowth and reharvests, following decades or centuries of cultivation-based agriculture and other land uses. The visible change in the boundaries of forests and fields is matched by similar, though less visible, patterns in the soils. Indeed, the soils that form the living surface of the Earth below may be as different on each side of the...

In the Sand County Almanac (Leopold 1949), Aldo Leopold writes of the odyssey of element X and thus of the circulation of all nutrient elements as they cycle through the Earth's forests, rangelands, lakes, and oceans. In mid-century, G.E. Hutchinson, while always one to praise aesthetic values, commented disparagingly about the quantitative science of element cycling, specifically that ecosystem carbon (C) data were "wretchedly inadequate" (Hutchinson 1954). Hutchinson's comment was not only a complaint but also a challenge to all ecosystem scientists who followed to quantify the Earth's...

The global population is expected to exceed 11 billion before the end of the twenty-first century (United Nations 2015). Populations within urban areas are also increasing, with the number of mega-sized (ten million people or more) cities expected to increase from 10 in 1990 to 41 in 2030 (United Nations 2015). In the United States, the human population is not growing as fast as the rest of the world, but the expansion of urban areas has proportionally kept pace, or exceeded, global estimates, with land devoted to urban uses growing by more than 34% between 1980 and 2000 alone (USDA NRCS...

Soil and the inherent biogeochemical processes in wetlands contrast starkly with those in upland forests and rangelands. The differences stem from extended periods of anoxia, or the lack of oxygen in the soil, that characterize wetland soils; in contrast, upland soils are nearly always oxic. As a result, wetland soil biogeochemistry is characterized by anaerobic processes, and wetland vegetation exhibits specific adaptations to grow under these conditions. However, many wetlands may also have periods during the year where the soils are unsaturated and aerated. This fluctuation between...

OPHISAURUS VENTRALIS (Eastern Glass Lizard). HABITAT USE. Burrowing crayfish and their burrows are common throughout the southeastern USA in intermittently wet habitats and terrestrial habitats with shallow water tables (Welch et al. 2008

Assessing species establishment risk is an important task used for informing biosecurity activities aimed at preventing biological invasions. Propagule pressure is a major contributor to the probability of invading species establishment; however, direct assessment of numbers of individuals arriving is virtually never possible. Inspections conducted at borders by biosecurity officials record counts of species (or higher-level taxa) intercepted during inspections, which can be used as proxies for arrival rates. Such data may therefore be useful for predicting species establishments, though...

Longleaf pine is an important tree species in the southeastern United States and studying the temporal patterns of pollen shedding is crucial to a better understanding of its phenology and seed production. In this study, field observation data on the timing of pollen shedding from 1958 to 2013 were analyzed with reference to local weather conditions. Our results indicated that the time of peak pollen shedding after January 1 (TPPS) ranged from 53 days (about February 22) to 95 days (around April 5). There was no significant trend of decreasing TPPS. The number of days with the maximum air...

Subtropical China has a large area of Acacia mangium plantations; however, some key aspects of the structural and functional changes and the associated mechanisms after planting are still not well understood. We established a permanent plot in an A. mangium plantation and monitored the plant diversity (i.e., the number of species), biomass, soil physical and chemical properties and light transmittance from 1984 to 2018. Protocols for standard observation and measurement of Chinese Ecological Research Network were adopted. The total number of species in the plantation increased gradually...

This report describes a long-term impact evaluation conducted by a Forestry Extension program. Documenting long-term impacts is increasingly important to demonstrate the perceived public value of Extension programming. However, the extended time frame of forestry activities creates challenges for technology transfer, including the realization of learning objectives and reporting to administrators and public officials. Mississippi State University has attempted to address these challenges through in-person impact evaluation. Three years of results are presented from an ongoing long-term...

Once dominant across the United States (US) Southeastern Coastal Plain, the longleaf pine (Pinus palustris Mill.) ecosystem covers a fraction of its historic geographic range. Restoration efforts have largely occurred on public lands, while most private forests feature alternative pine species. A better understanding of public interest in ecological restoration is critical to sustained efforts and successes. This research examines both forest landowner and general public interest in longleaf pine restoration. Results contribute to research on the social dimensions of ecological restoration,...