Treesearch

The Walnut Gulch LTAR builds on and advances 60 years of research on the USDA-ARS Walnut Gulch Experimental Watershed surrounding the town of Tombstone in southeast Arizona. Instrumentation on the watershed was initiated in 1953 and currently approximately 149 square kilometers of semiarid rangeland are monitored and serve as an outdoor laboratory. The watershed is a tributary to the upper San Pedro Basin that drains northward spanning the Mexico-U.S. border.

The Southern Plains (SP) site of the Long Term Agroecosystem Research (LTAR) network is headquartered at the USDA-ARS Grazinglands Research Laboratory (GRL) in El Reno, Oklahoma. The GRL was established in 1948. A long-term watershed and climate research program was established in the Little Washita River Experimental Watershed (LWREW) in 1961 and in the Fort Cobb Reservoir Experimental Watershed (FCREW) in 2004 (Steiner and others 2014). The GRL mission is to develop technologies, management strategies, and tools to evaluate and manage risks and tradeoffs for integrated crop, forage, and...

Post oak (Quercus stellata) is a commonly occurring tree in the southeastern United States, offering forage and shelter for a variety of wildlife as well as having commercial uses. This species is often planted in parks and urban green-spaces for the shade it offers. Previous studies have found that parts of the plant can be toxic to livestock and that it can inhibit the germination and/or growth of plant species in its vicinity. This study focuses on the allelopathic potential of post oak in an urban, old growth forest. Post oak was selected subsequent to an understory inventory of plant...

Sap flux sensors are an important tool for estimating tree-level transpiration in forested and urban ecosystems around the world. Thermal dissipation (TD) or Granier-type sap flux probes are among the most commonly used due to their reliability, simplicity, and low cost.

Over the last several years, a partnership of over thirty organizations called the Conewago Creek Initiative has been working cooperatively in a small watershed to increase community engagement and work with farmers and landowners to adopt land management practices to improve water quality.

Youth in Pennsylvania’s Dauphin, Lebanon, and Lancaster Counties were invited to be part of a unique opportunity: a chance to learn, hands-on, about the water in their own community and how their daily lives impact that water. This is the mission of the 4-H Stream Teams program, which was piloted within the Conewago Creek Watershed and surrounding communities in 2010-2013.

Attaining high quality water has always been a big concern for humankind. Forested watersheds are known to provide the cleanest form of water. However, conversion of forested lands to agricultural and/or urban use, as well as disturbances created in forested watersheds lead to degradation and deterioration of our water resources.

Despite a general consensus that the Earth’s hydrologic cycle is intensifying as a result of anthropogenic climate forcing (e.g. Huntington 2006), there remains substantial uncertainty over the consequences of this intensification for terrestrial evapotranspiration (ET; e.g., Hobbins and others 2004, Walter and others 2004, van Heerwaarden and others 2010). Most models indicate that climate change will cause an increase in ET, but evidence from field observations has been inconsistent. Unidirectional changes in ET could profoundly alter local water balances and streamflow dynamics, having...

Forest productivity will only become more important in the future, not just for carbon sequestration and renewable energy but for wood products and economic security for an increasing population. However, the threat of increasing drought and resource scarcity means a need for more explicit characterization of the water use of planted forests and the understanding of productivity trade-offs necessary to reduce water use.

There is a significant lack of continuously measured ET data for multiple land surfaces in the same area to be able to make comparisons of water use rates of different agroecosystems. This research presentation will provide continuous evapotranspiration and other surface energy balance variables measured above multiple land use and management practices.