Biological Characteristics of soil SAQ's Q & A.docx

What is the ideal pH range for earthworms to thrive in soil? ANSWER: pH 6-8 What is the purpose of adding FYM to the soil in terms of earthworms? ANSWER: To act as food for worms, increasing their population and improving soil structure What is the primary function of microorganisms in the decay...

What is the ideal pH range for earthworms to thrive in soil? ANSWER: pH 6-8 What is the purpose of adding FYM to the soil in terms of earthworms? ANSWER: To act as food for worms, increasing their population and improving soil structure What is the primary function of microorganisms in the decay process of the carbon cycle? ANSWER: Breaking down organic matter and releasing CO2 What is the primary role of microorganisms in the soil, and how do they benefit from the plant\'s root? ANSWER: Primary role: decompose organic matter, convert nutrients into usable forms. Benefit: feed on compounds exiting the roots. What is the term used to describe the total amount of organic matter living in the soil? ANSWER: Soil biomass What is the term used to describe the total amount of greenhouse gases produced by a farmer\'s activities? ANSWER: Carbon footprint What is the symbiotic relationship between mycorrhizal fungi and plants, and what benefits do they provide to the plant? ANSWER: Mycorrhizal fungi provide water, nutrients, and disease resistance to the plant, while the plant provides compounds for the fungi. How do farmers reduce their carbon footprint through tillage practices? ANSWER: Eco-tillage and minimum tillage What is the percentage of organic carbon in soil organic matter? ANSWER: 58% What is the role of earthworms in soil, and how do they contribute to soil fertility? ANSWER: Earthworms add nutrients in the form of faeces, decompose organic matter, and add organic matter when they die. What is the role of rhizobium bacteria in the nitrogen fixation process? ANSWER: Converting nitrogen gas (N2) to nitrate (NO3-) What is the difference between a symbiotic relationship and a mutualistic relationship? ANSWER: Symbiotic: one or more organisms benefit, neither are harmed. Mutualistic: both organisms benefit from the relationship. What is the primary function of bacteria in soil, and how do they contribute to soil fertility? ANSWER: Primary function: convert organic matter into humus, convert nitrogen into usable forms. Contribute to soil fertility by making nutrients available to plants. What is the term used to describe the area around a plant root where the biological and chemical aspects of the soil are influenced by the root? ANSWER: The rhizosphere What is the primary mechanism by which reducing soil disturbance can help mitigate climate change? ANSWER: Reducing soil disturbance can help reduce the amount of carbon that enters the atmosphere, allowing it to be stored in the soil where it can provide energy for the soil microbiome. What is the role of rhizobium bacteria in legume plants, and how does it contribute to the nitrogen cycle? ANSWER: Rhizobium bacteria fix nitrogen (N2) into nitrate (NO3-) in the nodules of legume plants, allowing plants to take up and store nitrogen as protein. What is the difference between ammonium (NH4) and nitrite (NO2-) in the nitrogen cycle? ANSWER: Ammonium (NH4) is converted to nitrite (NO2-) by Nitrosomas bacteria during nitrification. What is the role of denitrifying bacteria in the nitrogen cycle, and under what conditions do they thrive? ANSWER: Denitrifying bacteria convert nitrate (NO3-) back to nitrogen gas (N2) under anaerobic conditions in waterlogged soils. What is the purpose of minimum tillage in reducing soil disturbance, and how does it impact the carbon cycle? ANSWER: Minimum tillage reduces soil disturbance, allowing carbon to be stored in the soil and providing energy for the soil microbiome. What is the role of microorganisms in decomposing organic matter in the soil, and how does it contribute to the nitrogen cycle? ANSWER: Microorganisms decompose organic matter, releasing nutrients such as nitrogen that can be used by plants. What is the difference between nitrogen fixation and nitrification in the nitrogen cycle? ANSWER: Nitrogen fixation is the conversion of nitrogen gas (N2) to nitrate (NO3-), while nitrification is the conversion of ammonium (NH4) to nitrate (NO3-). How do legume plants contribute to the nitrogen cycle, and what is the role of rhizobium bacteria in this process? ANSWER: Legume plants take up and store nitrogen as protein through the process of nitrogen fixation, which is facilitated by rhizobium bacteria. What is the role of bacteria in the nitrogen cycle, and how do they contribute to soil fertility? ANSWER: Bacteria convert nitrogen gas (N2) to nitrate (NO3-) through nitrogen fixation, and convert ammonium (NH4) to nitrate (NO3-) through nitrification. What is the impact of soil disturbance on the carbon cycle, and how can it be mitigated? ANSWER: Soil disturbance can lead to the release of carbon into the atmosphere, contributing to climate change. This can be mitigated through practices such as minimum tillage and stopping the cultivation/harvesting of peat. How do earthworms contribute to the humification process in soil? ANSWER: Earthworms contribute to the humification process by decomposing organic matter to humus and recycling nutrients. What is the significance of the rhizosphere in soil ecology? ANSWER: The rhizosphere is the area around a plant root where the biological and chemical aspects of the soil are influenced by the root, and it plays a critical role in plant-soil interactions. How do symbiotic relationships between mycorrhizal fungi and plants benefit soil fertility? ANSWER: Mycorrhizal fungi enhance water holding capacity, bind soil particles together, and help with disease resistance, ultimately benefiting soil fertility. What conditions are necessary for optimal soil biomass, and how can they be achieved? ANSWER: Optimal soil biomass requires a pH between 6-8, moist soil, and high levels of organic matter, which can be achieved by adding lime, managing water levels, and spreading FYM or other organic manures. What is the significance of soil biomass in maintaining soil fertility, and how does it impact ecosystem functioning? ANSWER: Soil biomass is the total amount of organic matter living in the soil, and it plays a critical role in maintaining soil fertility by decomposing organic matter, recycling nutrients, and improving soil structure. What conditions are necessary for microorganisms to thrive in soil, and how do these conditions impact the carbon cycle? ANSWER: Warm soil above 10°C and well-aerated soil, which allows for efficient decomposition and carbon sequestration. Explain the role of bacteria in the nitrogen cycle, highlighting their involvement in nitrogen fixation, nitrification, and denitrification. ANSWER: Bacteria convert N2 to NO3- through nitrogen fixation, convert NH4 to NO3- through nitrification, and convert NO3- back to N2 through denitrification, recycling nitrogen in the soil. How do farmers reduce their carbon footprint in agriculture, and what are the benefits of these practices for the environment? ANSWER: Farmers reduce their carbon footprint by planting more trees, reducing diesel usage, growing biofuels, not burning straw, and practicing minimum tillage, which reduces emissions, conserves energy, and promotes soil carbon sequestration. Explain how to calculate Soil Organic Carbon (SOC), and why is it an important indicator of soil health. ANSWER: SOC is calculated by multiplying the percentage of Soil Organic Matter (SOM) by 0.58, and it\'s an important indicator of soil health because it influences soil structure, fertility, and carbon sequestration. Describe the processes involved in the nitrogen cycle, and what forms of nitrogen are converted during each process. ANSWER: The nitrogen cycle involves nitrogen fixation (N2 to NO3-), decomposition (organic matter to NH4 and NO3-), nitrification (NH4 to NO2- to NO3-), and denitrification (NO3- to N2).