Ecology, Environment and Climate Change in Agriculture MCQs 2026

The farming system formed by crops, livestock, soil organisms and their physical environment is best called

1. AAgroecosystem✓
2. BNatural ecosystem✓
3. CEcotone✓
4. DBiome✓

The ecological rule stating that only a small fraction of energy passes to the next trophic level is the

1. ALaw of limiting factors✓
2. B10 percent law✓
3. CLaw of dominance✓
4. DHardy-Weinberg law✓

The nutrient most commonly limiting crop productivity in many intensively cultivated agroecosystems is

1. ASodium✓
2. BSilicon✓
3. CChloride✓
4. DNitrogen✓

Using predators, parasitoids or pathogens to suppress an agricultural pest is known as

1. AChemical sterilization✓
2. BMechanical tillage✓
3. CBiological control✓
4. DGenetic drift✓

Storing atmospheric carbon in soil organic matter and plant biomass is termed

1. ACarbon sequestration✓
2. BCarbon fixation only✓
3. CCarbon leakage✓
4. DCarbon volatilization✓

Flooded rice fields mainly emit which greenhouse gas because of anaerobic decomposition

1. AOxygen✓
2. BSulfur dioxide✓
3. CMethane✓
4. DAmmonia✓

The soil component that improves aggregation, cation exchange capacity and water holding is

1. ACoarse sand only✓
2. BSoil organic matter✓
3. CSoluble salts✓
4. DCalcium carbonate crust✓

Nutrient enrichment of water bodies that causes algal blooms is called

1. ADesertification✓
2. BCalcification✓
3. CVernalization✓
4. DEutrophication✓

Combining cultural, biological, mechanical and chemical tactics based on pest thresholds is called

1. ABroadcast fertilization✓
2. BIntegrated pest management✓
3. CGreen revolution✓
4. DRelay cropping✓

A row of trees planted to reduce wind speed and wind erosion around fields is known as

1. AShelterbelt or windbreak✓
2. BBuffer stock✓
3. CCheck basin✓
4. DSeed orchard✓

Chlorofluorocarbons are most closely associated with which environmental problem

1. ASoil compaction✓
2. BWaterlogging✓
3. COzone layer depletion✓
4. DBiological nitrogen fixation✓

The 2015 international agreement aimed at limiting global temperature rise is the

1. ARamsar Convention✓
2. BBasel Convention✓
3. CCartagena Protocol✓
4. DParis Agreement✓

Growing a crop such as sesbania or mungbean and incorporating it into soil to add organic matter is

1. AGreen manuring✓
2. BRatooning✓
3. CPruning✓
4. DGinning✓

Changing crops in a planned sequence on the same field mainly helps break pest cycles and maintain soil fertility; this practice is

1. AMonocropping✓
2. BCrop rotation✓
3. CDefoliation✓
4. DPuddling✓

The method used to evaluate environmental impacts of a product from inputs through disposal is

1. AMass selection✓
2. BSoil texturing✓
3. CLife cycle assessment✓
4. DTiller counting✓

The tillage approach that leaves residues on the soil surface and minimizes soil disturbance is

1. ANo-till or conservation tillage✓
2. BDeep inversion ploughing✓
3. CRepeated harrowing✓
4. DBare fallowing✓

The combined loss of water from soil evaporation and plant transpiration is

1. APercolation✓
2. BInfiltration✓
3. CCondensation✓
4. DEvapotranspiration✓

Conserving crop landraces in their natural farming areas is an example of

1. AEx-situ conservation✓
2. BIn-situ conservation✓
3. CMutation breeding✓
4. DHydroponics✓

The gradual replacement of one plant community by another over time is called

1. AAllelopathy✓
2. BOsmoregulation✓
3. CEcological succession✓
4. DPhotoperiodism✓

The warming effect caused when atmospheric gases absorb outgoing longwave radiation is the

1. AGreenhouse effect✓
2. BRain shadow effect✓
3. CEdge effect✓
4. DFounder effect✓

Tillage and planting across a slope along lines of equal elevation is called

1. AStrip mining✓
2. BContour farming✓
3. CZero grazing✓
4. DBroadcast sowing✓

The microbial conversion of nitrate into nitrogen gases under anaerobic soil conditions is

1. ANitrification✓
2. BAmmonification✓
3. CMineralization✓
4. DDenitrification✓

The variety of genes, species and ecosystems in a region is called

1. ABiodiversity✓
2. BBiofortification✓
3. CBiomass yield✓
4. DBiological half-life✓

The United Nations body that assesses scientific knowledge on climate change is

1. AFood and Agriculture Organization only✓
2. BWorld Trade Organization✓
3. CIntergovernmental Panel on Climate Change✓
4. DInternational Rice Research Institute✓

The land-use system that deliberately combines trees with crops or livestock is

1. AAquaculture✓
2. BAgroforestry✓
3. CSericulture✓
4. DApiculture✓

The accumulation of soluble salts in the root zone due to poor irrigation and drainage is

1. APodzolization✓
2. BLaterization✓
3. CHumification✓
4. DSalinization✓

The symbiotic association between plant roots and fungi that improves phosphorus uptake is

1. ARhizome✓
2. BLichen only✓
3. CMycorrhizae✓
4. DNematode cyst✓

The measure of biologically productive area needed to supply resources and absorb wastes for a population is

1. AEcological footprint✓
2. BCrop coefficient✓
3. CLeaf area index✓
4. DHarvest index✓

The most abundant long-lived anthropogenic greenhouse gas emitted globally by human activities is

1. AMethane✓
2. BCarbon dioxide✓
3. CNitrous oxide✓
4. DOzone✓

The conservation agriculture principle set includes minimum soil disturbance, permanent soil cover and

1. AContinuous bare fallow✓
2. BFrequent residue burning✓
3. CSingle-crop monoculture only✓
4. DDiverse crop rotations✓

The charcoal-like product of heating biomass under limited oxygen that can improve soil carbon storage is

1. ABiochar✓
2. BGypsum✓
3. CBentonite✓
4. DRock phosphate✓

A species whose presence or absence signals a particular environmental condition is an

1. APioneer seed✓
2. BHybrid cultivar✓
3. CIndicator species✓
4. DAnnual weed only✓

Rainfall made more acidic mainly by sulfur and nitrogen oxides is known as

1. ABlack rain✓
2. BAcid rain✓
3. CVirga✓
4. DMonsoon burst✓

The pest density at which control action should begin to prevent economic loss is the

1. AEconomic threshold✓
2. BCarrying capacity✓
3. CBase population✓
4. DReplacement level✓

The microbial oxidation of ammonium first to nitrite and then nitrate is called

1. ADenitrification✓
2. BImmobilization✓
3. CLeaching✓
4. DNitrification✓

The index comparing the heat-trapping ability of a gas with carbon dioxide over a set time is

1. ABase saturation✓
2. BLeaf water potential✓
3. CGlobal warming potential✓
4. DRespiration quotient✓

The irrigation method usually most efficient for delivering water directly to the crop root zone is

1. AWild flooding✓
2. BDrip irrigation✓
3. CBorder flooding✓
4. DUncontrolled basin irrigation✓

Breaking a large continuous habitat into smaller isolated patches is termed

1. AHabitat fragmentation✓
2. BSoil flocculation✓
3. CCrop lodging✓
4. DSeed dormancy✓

In water footprint terminology, surface water and groundwater consumed in production are called

1. AGreen water✓
2. BGrey water✓
3. CVirtual nitrogen✓
4. DBlue water✓

A major agricultural consequence of declining bees and other pollinators is reduced

1. ASoil pH only✓
2. BFruit and seed set✓
3. CWind speed✓
4. DBulk density✓

Growing one crop species over a large area or repeatedly on the same land is called

1. AIntercropping✓
2. BRelay cropping✓
3. CMonoculture✓
4. DMixed farming✓

The increase in concentration of persistent toxins at higher trophic levels is

1. ABiomagnification✓
2. BBioremediation✓
3. CBiological fixation✓
4. DBiofertilization✓

A prolonged period of abnormally low rainfall causing crop moisture stress is

1. AFrost heave✓
2. BDrought✓
3. CWaterlogging✓
4. DHail drift✓

The approach that aims to increase productivity, strengthen adaptation and reduce emissions where possible is

1. ASlash-and-burn agriculture only✓
2. BShifting cultivation only✓
3. CSingle input agriculture✓
4. DClimate-smart agriculture✓

Agriculture that meets present food needs while conserving resources for future generations is

1. AExhaustive agriculture✓
2. BExtractive agriculture✓
3. CSustainable agriculture✓
4. DAbandoned agriculture✓

The fraction of incoming solar radiation reflected by a surface is called

1. AEntropy✓
2. BAlbedo✓
3. CTurbidity✓
4. DOsmosis✓

Preserving seeds or plant genetic material in a gene bank is an example of

1. AEx-situ conservation✓
2. BIn-situ conservation✓
3. CNatural selection✓
4. DEcological succession✓

Leaving crop residues as a soil cover mainly reduces evaporation and

1. APhotosynthesis✓
2. BSeed purity✓
3. CPlant population✓
4. DSoil erosion✓

The capacity of an agroecosystem to absorb disturbance and recover function is called

1. AVolatilization✓
2. BSenescence✓
3. CResilience✓
4. DEmulsification✓

The greenhouse gas with high warming potential commonly emitted from nitrogen fertilizers and manure is

1. AHydrogen sulfide✓
2. BCarbon monoxide✓
3. CHelium✓
4. DNitrous oxide✓