Question

Which of the following is most likely to cause erosion of farmland during a severe drought? A. water runoff B. soil creeping downhill C. wind D. ice Use the table below to answer questions \(8-10\). \begin{tabular}{|c|c|c|c|} \hline \multicolumn{4}{|c|}{ Texture Data for a Soil Profile } \\ \hline \multirow{2}{*}{ Horizon } & \multicolumn{3}{|c|}{ Percent } \\ \cline { 2 - 4 } & Sand & Silt & Clay \\ \hline A & \(16.2\) & \(54.4\) & \(29.4\) \\ \hline B & \(10.5\) & \(50.2\) & \(39.3\) \\ \hline C & \(31.4\) & \(48.4\) & \(20.2\) \\ \hline\(R\) (bedrock) & \(31.7\) & \(50.1\) & \(18.2\) \\ \hline \end{tabular}

Short answer

The most likely cause of erosion during a drought is wind (Option C).

Step-by-step solution

Understanding the Question

The question asks which factor is most likely to cause erosion of farmland during a severe drought. Drought conditions usually mean very little water is present, so we must consider which factor is prominent in such dry conditions.

Examining the Options

The options given are: A) water runoff, B) soil creeping downhill, C) wind, and D) ice. Under drought conditions, water runoff is unlikely as there is little water. Soil creeping downhill typically occurs due to gravity on a slope regardless of drought but is slower. Ice would not form in drought conditions.

Understanding Erosion Processes

Erosion is the process by which soil and rock are removed from the Earth's surface by wind, water, or other natural agents. In dry conditions, wind is a significant contributor to erosion as it can pick up and carry away loose soil particles.

Identifying the Correct Option

Given that drought conditions mean dry, barren land without sufficient moisture to hold soils in place, the factor most contributing to erosion during this time is C) wind. Wind can cause significant erosion in dry conditions by blowing away the topsoil.

Key concepts

Soil Erosion

Soil erosion is a natural process that involves the removal and transportation of the top layer of soil from one location to another. This can occur due to several natural forces such as water, ice, or wind. When soil erosion occurs, it leads to the loss of the nutrient-rich upper soil layer, which is crucial for plant growth. Understanding the causes and impacts of soil erosion is essential in agriculture and environmental conservation.

Key contributors to soil erosion include:

• Rainwater, which can lead to water erosion when it washes away soil particles.
• Wind, which contributes to erosion by carrying away loose and dry soil particles, especially in arid regions.
• Human activities, such as deforestation and poor agricultural practices, which can accelerate erosion.

Soil erosion can have severe consequences, such as reducing soil fertility, lowering agricultural productivity, and leading to sediment accumulation in water bodies.

Wind Erosion

Wind erosion occurs when strong winds sweep over loose, dry, and bare soil, lifting and carrying away soil particles. This type of erosion is most pronounced in regions where vegetation cover is sparse, such as deserts or areas facing drought conditions. The intensity of wind erosion depends on various factors, including wind speed, soil texture, and lack of vegetation.

Impacts of wind erosion are numerous:

• Loss of nutrient-rich topsoil, which diminishes land's productivity.
• Formation of dust storms, which reduce air quality and visibility.
• Damage to crops by the abrasive action of wind-carried soil particles.

Preventing wind erosion involves techniques such as planting windbreaks, maintaining ground cover, and improving land management practices to keep the soil moist and compact.

Drought Conditions

Drought conditions occur when an area experiences a prolonged period of low precipitation, resulting in a significant water deficiency. This environment can result in dry, arid soil, which is more susceptible to erosion, particularly wind erosion.

During droughts, the following challenges may arise:

• Reduced agricultural output due to insufficient water for irrigation and plant growth.
• Increased risk of wind erosion as dry, loose soil is easily picked up by wind.
• Potential loss of biodiversity as plants and animals struggle to survive in water-scarce conditions.

Managing drought conditions effectively involves water conservation measures, drought-resistant crop varieties, and strategic irrigation practices to minimize soil erosion and maintain soil health.

Soil Profile Analysis

Soil profile analysis involves examining the different layers, or horizons, of soil to understand its structure, composition, and characteristics. Each horizon has distinct physical and chemical properties, such as texture, nutrient content, and moisture level, which influence how the soil supports plant life.

Analyzing a soil profile typically includes:

• Determining soil texture by measuring the proportions of sand, silt, and clay in each horizon.
• Assessing soil fertility and structure for agricultural suitability.
• Identifying signs of erosion or degradation within the soil layers.

This information is crucial in agriculture and land management, as it helps guide soil conservation strategies, crop selection, and irrigation practices to optimize land use while preventing soil erosion.