Tag: Evapotranspiration

Linking tree water use and soil moisture

by Sarah Farmer, SRS Science Communications  • 
When more water is available, some tree species use much more of it. Loblolly pines growing near a stream used 65 percent more water than loblolly pines growing near the top of a hill, reports a new study led by USDA Forest Service researcher Johnny Boggs.  White oaks near a stream only had 12 percent…  More 

Where Does the Rain Go?

by Naomi Cohen-Shields, SRS Science Communications Intern  • 
Millions of people depend on the forests of the Southern Appalachian Mountains for drinking water. As climate, land use, and land cover changes alter the forest structure in these mountains, they also alter water budgets. “The Southern Appalachian Mountains are a humid montane environment – they are essentially a cooler version of the tropics,” explains…  More 

Species Selection for Woody Biomass Production

by Jennifer Moore Myers, SRS Science Communications  • 
In the southeastern U.S., short-rotation woody crops are a significant part of a growing renewable energy supply. A USDA Forest Service study examines how growing different tree species for bioenergy may have impacts on water yield. “Loblolly pine has long been considered the go-to woody bioenergy species in the South,” says Peter Caldwell, research hydrologist…  More 

How Drought and Thinning Affect Water Balances in Southeastern Pine Plantations

by Megan Bequette, SRS Science Communication Intern  • 
Evapotranspiration – the combination of water evaporation and plant transpiration – is an essential process for forests and water supply and climate. This is particularly true in the Southeastern U.S. where evapotranspiration from forested watersheds can return 50 to 90 percent of annual precipitation to the atmosphere. Until now, there has been a gap in…  More 

Estimating Ecosystem Water Use

by Jennifer Moore Myers, SRS Science Communications  • 
For more than a decade, U.S. Forest Service and Chinese scientists have collaborated to understand how human activities affect carbon and water cycles in managed ecosystems. Working through the U.S.-China Carbon Consortium, scientists share data from a network of eddy covariance flux towers across the two countries. The towers measure the flow of water vapor,…  More 

Forests, Water, Climate, and Management

by Sarah Farmer, SRS Science Communications  • 
Across the globe, forests cover about a quarter of all land and are important sources of clean water. A new book, edited by U.S. Forest Service Southern Research Station (SRS) scientist Devendra Amatya, examines the interactions between forests, water, climate, and management. The book, Forest Hydrology: Processes, Management and Assessment, was recently published by the…  More 

Open or Shut: How Trees Respond to Drought at the Leaf Level

by Sarah Farmer, SRS Science Communications  • 
Trees pull water into their roots, where some of it moves up the trunk against the pull of gravity. This upward movement, which is described by the cohesion-tension theory, is possible because of the chemical nature of water. Water molecules are attracted to each other (cohesion), so just before a water molecule evaporates from the…  More 

International Evapotranspiration Symposium: April 7 – 10, 2014, Raleigh, NC

by Sarah Farmer, SRS Science Delivery Group  • 
  Register now for Evapotranspiration: Challenges in Measurement and Modeling from the Leaf to the Landscape Scale and Beyond. An important part of the hydrologic water cycle is plant water use (transpiration) and evaporation from earth and ocean surfaces. Together, these two processes are called evapotranspiration. Scientists and engineers studying climate, ecosystem productivity, water use,…  More