Nutrient cycling in the Columbia River Basin eutrophication in part due to the use of the river and its tributaries to irrigate over seven million acres of farmland, an extraction that comprises an average of 93 percent of daily water use in the basin. Natural run-off caused by precipitation and snowpack melt across agricultural lands further transports more of these nutrients into the river. In the late 1990s, the nitrogen load in the Columbia river was over twice the concentration historically observed. Forests are important terrestrial sinks for nutrients due to the ability of vegetation to sequester excess nutrients into their biomass. Additionally, plant roots stabilize soils
Plant to plant communication via mycorrhizal networks reported to move via an AM network between conspecific plants. Workers believe that transfer of nutrients by way of mycorrhizal networks could act to alter the behavior of receiving plants by inducing physiological or biochemical changes, and there is evidence that these changes have improved nutrition, growth and survival of receiving plants. Several mechanisms have been observed and proposed by which nutrients can move between plants connected by a mycorrhizal network, including source-sink relationships, preferential transfer and kin related mechanisms. Transfer of nutrients can follow a source-sink relationship where nutrients move from areas of higher concentration to areas of lower