PTE

the presence or introduction of unwanted substances that make something impure or unsafe

a crop grown mainly to cover and protect or improve soil rather than to produce the main harvest

the practice of growing different crops in a planned sequence on the same land over successive seasons

the preparation and use of land for growing crops, or the growing of a particular crop

to use up or greatly reduce the available amount of a resource

land degradation in dry regions that reduces soil quality, vegetation, and biological productivity

irrigation that supplies water slowly through small outlets close to individual plants or their roots

left without a crop being grown for harvest for a period as part of land management

relating to or using heat from within Earth

the practice of growing two or more crops together on the same land during an overlapping period

to supply water to land or crops through an organized system rather than relying only on rain

material spread over the soil surface to help conserve moisture, limit unwanted plants, or protect the soil

to use a natural resource so intensively that its supply or ability to recover is damaged

an area of trees deliberately planted and managed to produce wood or another crop

water that falls from the atmosphere to the ground as rain, snow, hail, or other forms

farming that uses detailed information about variation within fields or herds to adjust management to local needs

a wind that blows from the direction most common in a place during a particular period

depending on rainfall rather than irrigation for the water needed by crops

the reestablishment of forest on land that previously supported forest, through planting or natural regeneration

to reestablish the water conditions, vegetation, and ecological functions of damaged wetlands

tree harvesting that removes selected trees while leaving others standing in the same area

to capture and store carbon for an extended period outside the atmosphere, in a biological or geological reservoir

wastewater containing human waste and other used water carried away from homes and buildings

the capacity of soil to provide nutrients in forms and amounts that support plant growth

a rise in coastal water level caused by a storm above the level expected from the normal tide

farming whose main purpose is to provide food for the farming household rather than for sale

irrigation in which water moves over the soil surface under gravity before entering the soil

an amount of a renewable resource that can be harvested repeatedly without undermining its long-term renewal under given conditions

an urban area that is warmer than surrounding less urbanized areas because of differences in surfaces, vegetation, and human activity