Which of the following is a method of soil conservation?

Contour farming is a method of soil conservation that involves plowing and planting across the slope of the land, rather than down the slope. This technique helps to reduce soil erosion by taking advantage of the natural contours of the land. By following the lines of elevation, contour farming slows down water runoff and encourages water infiltration, which helps to maintain soil moisture and prevent the loss of topsoil. This practice is particularly effective on hilly or sloped terrain where water can easily wash away unprotected soil.

In contrast, urban development tends to disrupt natural landscapes and can increase the risk of soil erosion due to the removal of vegetation. Overgrazing occurs when livestock feed on vegetation faster than it can regrow, leading to degradation of the soil and its ability to retain moisture. Destruction of wetlands results in the loss of critical ecosystems that naturally filter water and stabilize soil, leading to increased erosion and diminished soil quality. Thus, the contrasting practices underscore the importance and effectiveness of contour farming as a proactive approach to soil conservation.