Practice Soils and details Questions and Answers

• Which of the following soil organisms is generally too small to be seen without a microscope?
• Adding organic manure to soil mainly helps to increase the number of?
• Dead leaves and plant parts falling on the soil are broken down by soil organisms into a dark, nutrient-rich substance called?
• Which of the following is an example of a soil-friendly practice that supports beneficial microbial life?
• Soil that has a good population of beneficial microorganisms is generally considered to be?
• Which of the following mainly provides food and energy for most soil microorganisms?
• A soil sample taken from a forest floor usually shows which level of microbial activity compared to sandy desert soil?
• Which of the following microorganisms is specifically used to prepare biofertilizers for legume crops such as gram and pea?
• The 'Winogradsky column', a classic laboratory setup in soil microbiology, is used to demonstrate?
• Which technique uses fluorescently labelled DNA probes to directly visualise and identify specific microorganisms within soil samples under a microscope?
• The 'rhizosphere effect' refers to the phenomenon where microbial population density near plant roots is significantly higher than in?
• Biological soil crusts, formed by cyanobacteria, mosses and lichens on arid soil surfaces, primarily contribute to soil?
• The enzyme nitrogenase, responsible for biological nitrogen fixation, requires which two essential metal cofactors to function?
• Laboratory assays measuring a soil's 'denitrification potential' commonly use which technique, which blocks the final reduction step so nitrous oxide accum...
• Soil microbial community 'resilience' specifically refers to its ability to?
• The 'priming effect' in soil refers to a short-term change in the decomposition rate of native soil organic matter following the addition of?
• A farmer applies gypsum to reclaim a sodic (alkali) soil with a high exchangeable sodium percentage. Gypsum works mainly by supplying which ion, which repl...
• Which of the following best describes a 'soil profile', a term commonly used in soil science and pedology to study soil formation and classification?
• Which quick field technique for estimating soil texture, without laboratory equipment, involves wetting a small soil sample and pressing it between the thu...
• Soils high in 2:1 type expanding clay minerals such as montmorillonite develop deep cracks during the dry season and become sticky and swollen during the w...
• Which soil condition most directly limits oxygen availability to aerobic microorganisms, thereby shaping overall microbial community composition?
• Compared to synthetic fertilizers, biological nitrogen fixation generally contributes what kind of share to total nitrogen input in global agriculture?
• The soil microbial process that converts elemental sulphur into sulphate, the form usable by plants, mainly performed by Thiobacillus, is called sulphur?
• The relationship between mycorrhizal fungi and their host plant is generally classified as?
• Which factor most directly limits microbial activity in extremely dry, arid soils?
• The broader concept of 'soil health', as opposed to simple 'soil fertility', additionally places emphasis on which dimension?
• Which farming practice is most likely to reduce beneficial soil microbial diversity over time if used excessively?
• Biochar added to soil is believed to support beneficial microbial communities mainly by providing?
• Soil organisms such as nematodes and mites, larger than microbes but still very small, are classified under soil?
• The 'soil food web' concept describes interactions among soil organisms based mainly on?
• Which group of soil fungi, aside from mycorrhizae, forms beneficial associations living within plant tissues without causing disease?
• 'Suppressive soils', which naturally inhibit the development of certain soil-borne diseases, achieve this mainly due to?
• Which practice generally increases soil organic carbon and supports greater microbial biomass over time?
• The carbon-to-nitrogen (C:N) ratio of soil microbial biomass itself, as opposed to typical plant residues, is generally?
• Which technique directly counts total microbial numbers in a soil sample under a microscope, without needing to culture them?
• 'Biofilm' formation by soil bacteria mainly helps the microbial community by providing?
• Fungi and bacteria present in soil mainly survive by feeding on?
• The air spaces between soil particles mainly allow which gas to reach soil organisms?
• A field with hard, compacted soil that has never been ploughed generally has _____ microbial life compared to a well-tilled field.
• Packets of live beneficial bacteria sold to farmers for mixing with seed or soil before sowing are known as?