Explore key methods and principles of soil reclamation in agriculture, including practices, challenges, and environmental impacts related to restoring degraded soils for productive use.
Which soil amendment is most commonly used to reduce acidity in reclaimed agricultural soils affected by acid rain or over-fertilization?
Explanation: Lime is widely used to raise pH levels and neutralize soil acidity, making it effective for reclaiming acidic agricultural soils. Gypsum improves soil structure but does not significantly change pH. Sulfur actually lowers soil pH, making soils more acidic. Compost primarily adds organic matter and nutrients but has a limited effect on correcting strong acidity.
What is the primary technique used to reclaim soils that have become saline due to excessive irrigation in dry climates?
Explanation: Leaching with clean water washes excess salts below the root zone, reducing soil salinity and restoring productivity. Adding potassium fertilizer does not remove salts. Deep plowing may mix salts but not effectively remove them. Herbicides control weeds but do not affect soil salinity.
In regions affected by soil erosion, which method is commonly recommended to restore organic matter and improve soil structure?
Explanation: Cover cropping adds organic matter and protects soil from erosion, helping rebuild soil structure. Flooding can worsen certain types of soil damage. Frequent tilling can further degrade soil structure and organic content. Pesticide application addresses pests, not organic matter restoration.
After industrial dumping has led to heavy metal contamination, which soil reclamation method is often used to reduce the bioavailability of toxic metals to plants?
Explanation: Phytoremediation uses specific plants to uptake or stabilize heavy metals, reducing their risk to crops. Deep plowing may redistribute contaminants but not remove them. Increasing irrigation can spread pollutants without removing them. Liming may alter pH but is not always effective against metals.
What is a possible negative environmental consequence if soil reclamation is rushed without an assessment of local biodiversity?
Explanation: Neglecting biodiversity can favor invasive or non-native species, potentially outcompeting and reducing native plant diversity. Immediate crop failure is more likely due to agronomic factors. Permanent soil acidity is tied to amendment choice, not pace of reclamation. Rapid groundwater recharge is seldom a direct effect of reclamation speed.