The University of Georgia Costa Rica 2014-2015 Sustainability Report UGA Costa Rica 2014 - 2015 Sustainability Report - Page 41

Soils are more than just the ground beneath our feet. They are alive and constantly changing. implemented at the UGA Costa Rica campus. Soils are more than just the ground beneath our feet. They are alive and constantly changing, with a single gram of soil estimated to contain over 10,000 different species. All of these organisms inhabit a complex mixture of weathered minerals, water, and decaying organic materials. Completely unseen to the naked eye, soil microbial communities metabolically convert organic residues to carbon dioxide, releasing nutrients such as nitrogen and phosphorus in mineral forms readily available for plant uptake. Soil physical structure is maintained through the release of compounds by different soil organisms that enhance soil aggregation, reducing erosional losses and providing flood-mitigating services. Soils also are one of the largest carbon repositories, storing more carbon than in the atmosphere and in all terrestrial life combined. Maintaining biodiversity in soils ensures that these processes are allowed to continue regulating and provisioning services for human society. This is especially important in an agriculturally dependent region, such as San Luis de Monteverde, where economic livelihood is directly tied to soil fertility. Managing soils to maintaining desired ecosystem services requires knowledge of the natural capital of the soil, as not all soils are weathered equally. There are 12 broad soil orders across the globe, each defined by different physical and chemical properties, with these properties impacting potential land uses. Some soils, due to the minerals and organic matter present, can filter water inputs more efficiently than others. The highly weathered soils of the tropics, like those of Costa Rica, can have issues with nutrient availability due to the ability of the mineral phases present to lock away phosphorus. While not all soil properties can be impacted by management, many can be improved through knowledgeable intervention. Added soil organic material can increase soil water holding capacity as well as increase the ability of the soil to hold on to nutrients for slow release and uptake by plants during the growing season. Management efforts that enhance soil organic matter content, such as compost incorporation, can increase water use efficiency during the dry season when it is needed most. A better understanding of soil ecosystem services can only be acquired through targeted research. One such example at UGA Costa Rica is an ongoing investigation into the use of Mountain Microorganisms (MM) to reduce nutrient losses from applied organic fertilizers. The farm at UGA Costa Mountain Microorganisms (MM), seen below, is being researched in attempt to reduce the amount of nutrients lost from applied organic fertilizers. 2014 – 2015 Sustainability Report 41