{"thcode":2,"term":{"code":548,"name":"human impacts","parent":1174,"scope":"The effects, intentional or unintentional, beneficial or harmful, direct or indirect, which human activities have upon the environment and living things."},"uf":[],"bt":[{"code":1174,"name":"topics","parent":1,"scope":"Themes, subjects, and concerns for which USGS information resources are relevant."},{"code":1,"name":"Categories","parent":null,"scope":"Thematic terms for categorizing information resources.  This thesaurus is intended to support finding and understanding scientific information."}],"nt":[{"code":1725,"name":"abandoned mines and quarries","parent":548,"scope":"Mines and quarries that have been abandoned and may expose harmful chemicals to the environment."},{"code":1354,"name":"deforestation","parent":548,"scope":"Reduction in the density of forest cover or tree canopy, typically by harvesting trees for human use or clearing land for other purposes such as agriculture."},{"code":1671,"name":"dredging","parent":548,"scope":"Removal of sediments from water bodies to aid navigation or to transfer material to another location."},{"code":629,"name":"land use change","parent":548,"scope":"Effect of changing land use patterns on ecological systems."},{"code":750,"name":"mining hazards","parent":548,"scope":"Dangerous conditions which result from the extraction of naturally occurring mineral deposits.  Includes tunnel collapses, fires, and explosions."},{"code":852,"name":"overfishing","parent":548,"scope":"Taking too many fish from an area beyond the capacity for the population to replenish its numbers. The balance of the ecosystem is upset, leading to long-term depletion of fish stock."},{"code":853,"name":"overgrazing","parent":548,"scope":"The practice of allowing animals to eat vegetation, especially ground cover, beyond the capacity of the plant population to replenish itself. Leads to erosion and other harm to the ecosystem."},{"code":1293,"name":"waste treatment and disposal","parent":548,"scope":"The chemical and physical methods to recycle or dispose of materials which, without treatment, are deemed to have no further value or are too contaminated to be used."}],"rt":[{"code":6,"name":"acid deposition","parent":66,"scope":"The process by which emissions, chiefly sulfur and nitrogen compounds, either react with the atmosphere when deposited on earth by precipitation of snow, rain, or fog with a pH of 5.5 or below, or settle out as acidic particles or gases."},{"code":769,"name":"contamination and pollution","parent":1174,"scope":"Introduction of harmful substances into the environment by human action or natural processes."},{"code":311,"name":"ecology","parent":650,"scope":"Study of the relations between living plants and animals and their environment."},{"code":320,"name":"ecotoxicology","parent":650,"scope":"Scientific study of causes, dispersal, and effects of contaminants on the environment."},{"code":345,"name":"environmental health (human)","parent":533,"scope":"Effects of the environment on human health."},{"code":384,"name":"fires","parent":101,"scope":"Combustion, marked by flames or intense heat, in natural settings, often ignited by lightning or human activities.  For fires set as part of natural resource management, use 'controlled fires'."},{"code":531,"name":"hazards","parent":1174,"scope":"Potential dangers from both natural processes (e.g., earthquakes, floods, and climate change) and human impacts on the environment."},{"code":602,"name":"invasive species","parent":797,"scope":"Plant, animal, or microbe species that is non-native (or alien) to the ecosystem under consideration and whose introduction causes or is likely to cause economic or environmental harm, or harm to human health."},{"code":1075,"name":"social sciences","parent":1019,"scope":"Sciences concerned with the structure and interrelationships of human societies, human institutions and organizations, and human culture over time."},{"code":624,"name":"subsidence","parent":451,"scope":"Settling, compaction, or caving in of land caused by subsurface mining, ground-water withdrawal, or pumping of oil and gas."}]}