Glossary
- half-lifesearch for term
- The half-life of a herbicide describes the length of time it takes for 50% of the herbicide to break down to secondary compounds.
- herbaceoussearch for term
- Having little or no woody tissue.
- herbicidesearch for term
- A chemical substance used to destroy or inhibit the growth of plants, especially weeds.
- herbicide precipitationsearch for term
- Falling out of solution and sinking to the bottom.
- herbivoroussearch for term
- plant-eating
- humic acidsearch for term
- Produced when organic matter such as dead leaves and plant material decay. Humic acids can color water so that it appears reddish or reddish-brown, even black.
- hydraulic conductivitysearch for term
- Ability of a canal to transport water. Water-handling capacity.
- hydraulic gradientsearch for term
- The movement of water downward along the horizontal slope of the subsurface bedding plane.
- hydrologic cyclesearch for term
- The sequence of conditions through which water passes from vapor in the atmosphere through precipitation on land and water surfaces and then back to the atmosphere through evaporation and transpiration.
- hydrolysissearch for term
- Breaking down in water.
- hydrostatic headsearch for term
- A measure of water pressure. The pressure at a given point in a liquid measured in terms of the vertical height of a column of the liquid needed to produce the same pressure.
- hypereutrophicsearch for term
- An aquatic system with high productivity and very high nutrients.
- hypolimnionsearch for term
- the part of a lake below the thermocline made of water that is stagnant and of essentially uniform temperature except during the period of overturn.
- hypoxiasearch for term
- A deficiency of oxygen.
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