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Water, Air, and Soil

Lake Margaret, located south of the Lake Tahoe Basin, featuring the lake, two large boulders protruding from the water in the foreground, with conifer trees, a rocky mountain ridge, and blue sky in the background. Photo Credit: Tim Rains, U.S. Forest Service Water, air, and soil are three natural resources that we cannot live without. The Forest Service strives to protect, maintain, and restore these valuable assets now and into the future.

Water is one of the most important natural resources flowing from forests. The Forest Service manages the largest single source of water in U.S., with about one-fifth originating from 193 million acres of land which provides drinking water to 180 million people every day.

Soil provides nutrients, water, oxygen and heat to natural land areas.  Understanding the ability and capacity of soil to support an ecosystem plays an important role in land management decisions.  

Air is a third critical resource for humans, plants, animals and all other organisms within a natural area. Air must be monitored in order to control and lower pollution levels, control smoke caused by wildland fires, and to monitor air quality. The Forest Service monitors the effects of air pollution that may impair visibility, harm human health, injure trees and other plants, acidify or cause unnatural fertilization of streams and lakes, leach nutrients from soils, and degrade cultural resources, like archeological sites and historical buildings. Forest activities that can affect air quality such as prescribed burning, ski areas, and mining are also monitored to ensure compliance with air regulations for human health and to monitor possible impacts to natural resources.

What research is being conducted to protect these natural resources?

Research on water, air and soil provides scientists with information about these critical natural resources, how they are changing, and what is affecting them. Forest Service Research and Development focuses on the following four focus areas involving water, air and soil:

Basic Processes

This research focus area strives to understand the basic processes of water, air and soil and how they are affected by many disturbances including fire, drought, invasive species and more.

Climate Change Impacts

This research focus area looks at the long term effects of climate change on the water, air and soil within a natural area. Pollution added to an atmosphere, water, or soil will directly or indirectly affect a natural area, either immediately or in the future.

Extreme Event Effects

This research focus area examines how extreme events, including storms, fire, invasive species, and more, have on the water, air and soil in a natural area. Scientists also look at the effects of these events on watersheds located in the forest or grassland.

Watershed Management Tools

These tools help natural resource managers, planners, and landowners decide how to manage forest and grassland watersheds. Watershed Management Tools can also be used to educate the general public about ways to protect and improve watersheds.

Current Research Highlights

Effects of Drought on Forests and Rangelands in the United States

In simple terms, drought is a lack of water over a given temporal and spatial scale. Drought can be a severe natural disaster with substantial social and economic consequences. Historical and paleoclimatic evidence shows that drought has always impacted the physical environment and will continue to do so. Management actions can either mitigate or exacerbate the effects of drought. As drought regimes change, the ability to quantify and predict the impacts on forests and rangelands is critical to developing and implementing management actions to increase resiliency and adaptation.

Nitrogen Deposition Effects in California and the Pacific Northwest

This research study focuses on proposing strategies that will set limits on power plants, cars, farms and other industrial processes in order to slow down the effects and production of acid rain, algal blooms and mercury. The amount of mercury found in plants and animals is continuing to rise to toxic levels making it extremely dangerous to the infected plant or animal as well as any higher level food chain animals that may eat it. Scientists are proposing these levels based on scientific research they have been conducting involving observation of tree-inhabiting lichens and diatoms, a tiny single-cell algae that is very sensitive to changes in nitrogen levels.