Soil Management and Acid Rain Quiz

Acid Sulfate Soils

• Potential acid sulfate soils form in wetlands.
• Draining wetlands can create extremely acidic soils.

Agroforestry Systems

• Mixed cropping (trees and food crops) in tropical regions improves nitrogen and sulfur soil management compared to monocropping.
• Mixed cropping helps retain nitrogen and sulfur.

Soil Fertilization and pH

• Urea added to soil eventually lowers pH (makes it more acidic), not raises it. This is because urea converts to ammonium, which acidifies the soil over time.

Nitrogen Fertilizer with Inhibitors

• Farmers often pay more for nitrogen fertilizers with nitrification inhibitors.
• These inhibitors keep nitrogen in the soil longer.

Nitrogen Fixation

• Microbes convert atmospheric nitrogen into a usable form for plants.
• Vermiculite clays and humus retain nitrogen in the soil without microbial involvement.

Acid Rain

• Acid rain is precipitation with increased acidity due to pollutants.
• It damages natural ecosystems by acidifying soil and water.

Nitrate in Streams

• Streams draining forested areas have lower nitrate levels compared to those draining agricultural areas.
• Tree uptake reduces nitrates in forests.
• Fertilizers lead to higher nitrates from agricultural areas.

CAFOs and Nitrogen Pollution

• Concentrated animal feeding operations (CAFOs) release excess nitrogen from manure into water.
• Properly handling manure and using less fertilizer can manage this pollution.

Soil Nitrogen Levels

• Agricultural soils often have lower total nitrogen than nearby natural soils (forests or grasslands).
• Farming depletes nitrogen faster than it's replenished, while natural soils better recycle it.

Phosphorus in Cultivated Soils

• Cultivated soils typically have higher phosphorus content compared to natural soils due to fertilizer use.

Eutrophication and Phosphorus

• Eutrophication is increased algae growth due to nutrient runoff from farms.

Phosphorus Availability and Soil pH

• Soil pH affects phosphorus availability.
• Low pH: Phosphorus binds with iron and aluminum, making it unavailable.
• High pH: Phosphorus binds with calcium, making it unavailable.
• Optimal plant availability at pH 6-7.

Nutrient Fixation

• Nitrogen, potassium, and phosphorus become "fixed" in the soil through various processes. These processes can vary widely in their effectiveness and environmental impacts. Further details on the processes would help to fully understand these.

Luxury Consumption of Nutrients

• Plants can absorb more nutrients than needed (luxury consumption).
• Advantages: Extra nutrients can be stored.
• Disadvantages: Wastage of nutrients and potential soil imbalances.

Nutrient Overapplication

• Overapplying phosphorus can pollute water.
• Overapplying potassium can disrupt nutrient balance.

Plant Nutrient Deficiencies

• Calcium (Ca) deficiency symptoms show up in new growth.
• Magnesium (Mg) deficiency symptoms show up in older leaves.

Phytoliths

• Phytoliths are silica structures in plants giving rigidity and strength.

Micronutrient Application

• Large quantities of micronutrients should not be added to satisfy potential future needs because of toxicity.

Essential Nutrients

• Nitrogen is needed in larger quantities than molybdenum, but a deficiency in either nutrient can substantially affect tree growth.

Chelates

• Chelates improve nutrient absorption for plants by preventing them from being bound by soil particles.

Micronutrient Animal Toxicity

• Copper and selenium deficiencies and toxicities badly affect animals.

Plant Breeding and Micronutrients

• Plant breeders can improve nutrient use efficiency and reduce micronutrient toxicities.

Nitrogen Loss in Forests

• Clear-cutting forests can lead to nitrogen losses.
• Selective cutting can reduce these losses.

Nitrate Reduction in Groundwater

• Nitrate concentrations reduce as groundwater flows through a riparian buffer zone.

Cover Crops for Nitrate Leaching

• Ryegrass is a suitable cover crop for minimizing nitrate leaching.

Fertilizer Element Issues

• Nitrogen can pollute air and water.
• Phosphorus causes water pollution.
• Potassium affects soil health.

Organic vs. Inorganic Nutrients

• Comparison of organic and inorganic nutrient sources is available elsewhere, but without detail here.

Limiting Factors for Plant Growth

• A limiting factor is a necessary nutrient in insufficient quantity. A lack of a necessary nutrient negatively impacts plant growth.

Plant Tissue Analysis vs. Soil Testing

• Plant tissue analysis is useful when plants show symptoms of nutrient imbalance, while soil testing might not show this.

Soil Tests as Indicators

• Soil tests measure nutrient levels.
• They do not always show plant uptake or environmental risk.

Test your knowledge on various aspects of soil management, including acid sulfate soils, agroforestry systems, and the effects of fertilizers. This quiz also covers the impact of acid rain on environmental health and soil chemistry. Discover how different practices influence soil pH and nitrogen management.