Environmental carrying capacity (K): The number of individuals in a population that the resources of a habitat can support.
Environmental contamination: The presence of toxic substance in a habitat.
Environmental ethics: It is the field of applied ethics that consider the moral basis of environmental. responsibility; it also considers how humans should relate to the natural environment.
Ethology: An approach to study the animal behavior in the natural environment. Examine the causes of the evolution of behavior.
Eutrophication: The addition of nutrient materials to a body of water, which stimulates plant growth; resulting in changes in ecological processes and species composition there in; the decomposition process, takes oxygen from the water, leading to death of other species.
Evolutionary psychology: The science that explains the behavior of our ancestors as a direct result of adaptive evolution.
Flora: All of the plants found in a given area.
Food chain: A portion of a food web, most commonly a simple sequence of prey species and predator that consume them.
Food web: The complete set of food links between species in a community; a diagram indicating which ones are the eaters and which one are eaten.
Forb: Any broadleaf herbaceous plant growing in grasslands.
Founder effect: The extreme genetic drift because of isolation of a small population from a large population.
Fundamental niche: The role an organism might play in an ecosystem in the absence of competitor.
Gene-for-gene resistance: A mechanism for resistance to pathogens, in which resistance is triggered by the specific interaction of the products of the pathogens.
Green architecture: The practice of designing and building homes with environmental considerations such as energy efficiency, recycling and conservation of natural resources in mind.
Greenhouse effect: The heating of earth’s atmosphere by gases such as water vapor, carbon dioxide and methane; such greenhouse gases are transparent to sunlight and opaque to heat; thus sunlight-engendered heat builds up at earth’s surface and cannot be dissipated into the atmosphere.
Greenhouse gas: A gas that absorbs infrared radiation; carbon dioxide, methane, nitrous oxide,
chlorofluorocarbons and troposphere ozone are all greenhouse gases.
Habitat loss: The shrinkage and fragmentation of the habitat (the place where the organism grows) in which the species lives.
Habituation: The ability of an organism to get used to certain types of stimuli.
Halophyte: A plant that grows in a saline environment.
Hominins: All living and extinct human species, the only living hominines is Homo sapiens.
Indicator species: Any biological species that defines a trait or characteristic of the environment.
Keystone species: Species that have dominant influence on the composition of a community.
Landscape ecology: A sub discipline in ecology that focuses on connections among ecosystems in a particular area.
Macro consumers: Large organisms, mainly animals, which eat other organisms or organic matter; also called pathogens.
Micro consumers: Micro-organisms, such as bacteria and fungi, which break down the complex compounds of dead cells and absorb some of the decomposed products; also known as saprotrophs or
Municipal solid waste: The waste which includes paper, yard waste, food waste, plastics, metals, textiles, glass wood etc; but does not include agricultural and industrial wastes.
Nitrogenous waste: Nitrogen containing molecules that are produced as waste by the breakdown of proteins and nucleic acids.
Omnivore: A living organism that consumes both plant and animal food.
Plankton: Free-floating small organism inhabiting the surface water of lakes and oceans. Photosynthetic members of the plankton are referred as phytoplankton.
Protobiont: Aggregates of abiotically produced molecules surrounded by membrane; it cannot reproduce but do maintain internal chemical environment that differ from their surroundings.
Reconciliation ecology: The practice of making exploited lands more biodiversity-friendly.
Red tide: A red, orange or brown coloration of water caused by a bloom or population explosion of algae; red tides cause serious environmental harm and threaten the health of humans and animals.
Restoration ecology: The science and practice of restoring damaged or degraded ecosystems.
Secondary succession: Ecological succession after a disturbance that did not eliminate all the organisms originally living in the site.
Seed-tree cutting: A forest management technique in which almost all trees are harvested from an area in a single cutting, but a few desirable trees are left behind to provide seeds for the regeneration of the forest.
Shelterwood cutting: A forest management technique in which all mature trees in an area are harvested in a series of partial cutting over time.
Succession: It is a process of change during which a sequence of communities replaces one another in an orderly and predictable way.
Trophic cascade: The progression over successively lower trophic levels of the indirect effects of predator.
Understory: The small plants growing under the canopy of dominant plants.
Vulnerable species: A species which is likely to become endangered unless the circumstances threatening its survival and reproduction improve.
Mixed farming is defined as a system of farming on a particular farm which includes crop production, raising live stock, poultry, fisheries, bee keeping etc. to sustain and satisfy as many needs of the farmer as possible. Subsistence is important objective of mixed farming. While higher profitability without altering ecological balance is important in farming system.
Organic farming is a special type of farming in mixed farming. Organic farming is a method of farming mainly depends on organic recycling. Industrial agricultural chemicals like fertilizers, pesticides, herbicides etc. are not used or the minimum extent necessary. However, organic farming cannot replace the chemicals production technology since there is need for higher and higher production with ever growing population on limited land.
Cropping system is an important component of farming system: It represents cropping pattern used on a form and their interaction with resources, other farm enterprises and available technology, which determine their makeup.
Cropping pattern means the proportion of area under various at a point of time in a unit area. Or it indicates the yearly sequences and spatial arrangement of crops and fallow in an area.
Crop sequence and crop rotation are generally used synonymously.
Crop rotation refers to recurrent succession of crops are so chosen that soil health is not impaired.
Cropping scheme is the plan according to which crops are grown on individual plots of a farm with an object of getting maximum return form each crop without impairing the fertility of soil is known as cropping scheme.
Transpiration is the process by which water vapour leaver the living plant body and enters the atmosphere. It involves continuous movement of water from the soil into roots, through the stem and cut through the leaves to the atmosphere. The process include cuticular transpiration or direct evaporation in to the atmosphere from moist membranes through the cuticle, and stomatal transpiration or outward diffusion into the atmosphere through the stomata and lenticels vapour previously evaporated from imbibed membranes, into intracellular space within the plant.
Transpiration is an evaporation process. However, unlike evaporation from a water surface, plant structure and stomata behavior in conjunction with the physical principles governing evaporation modify transpiration.
The loss of water through transpiration is governed by temperature, humidity, wind velocity, moisture content in the soil and inherent characteristic of the plant. Since transpiration is a physiological process, which must continue, if the plant has to grow, the only way to save this loss is by growing such crops and their varieties whose transpiration co-efficient is low. Transpiration can be checked to some chemicals. Transpiration produces energy gradient, which causes movement of water into through plants.
When rainfall is high and water-holding capacity of soil is less, the losses due percolation are very great. Such losses are very rapid particularly when the soils are sandy and porous. In heavy soils, percolation is low because of more water holding capacity. Besides rapid percolation of water, there is also heavy loss of plant nutrients viz. Ca, Mg, S, K etc. resulting in soil becoming acidic. Percolation losses are maximum in humid climate. When high rainfall is received, the loss of water through percolation is necessary otherwise, poor drainage conditions and water logging may develop in heavy soils. When water is in excess of water holding capacity of soils, it percolates through the soil due to gravity.
Agriculture Related Terms For Competitive Examination Part-1