Topsoil in the context of "Groundcover"

Soil erosion is the denudation or wearing away of the upper layer of soil. It is a form of soil degradation. This natural process is caused by the dynamic activity of erosive agents, that is, water, ice (glaciers), snow, air (wind), plants, and animals (including humans). In accordance with these agents, erosion is sometimes divided into water erosion, glacial erosion, snow erosion, wind (aeolian) erosion, zoogenic erosion and anthropogenic erosion such as tillage erosion. Soil erosion may be a slow process that continues relatively unnoticed, or it may occur at an alarming rate causing a serious loss of topsoil. The loss of soil from farmland may be reflected in reduced crop production potential, lower surface water quality and damaged drainage networks. Soil erosion could also cause sinkholes.

Human activities have increased by 10–50 times the rate at which erosion is occurring world-wide.Excessive (or accelerated) erosion causes both "on-site" and "off-site" problems. On-site impacts include decreases in agricultural productivity and (on natural landscapes) ecological collapse, both because of loss of the nutrient-rich upper soil layers. In some cases, the eventual result is desertification. Off-site effects include sedimentation of waterways and eutrophication of water bodies, as well as sediment-related damage to roads and houses. Water and wind erosion are the two primary causes of land degradation; combined, they are responsible for about 84% of the global extent of degraded land, making excessive erosion one of the most significant environmental problems worldwide.

Criticism of capitalism typically ranges from expressing disagreement with particular aspects or outcomes of capitalism to rejecting the principles of the capitalist system in its entirety. Criticism comes from various political and philosophical approaches, including anarchist, socialist, religious, and nationalist viewpoints. Some believe that capitalism can only be overcome through revolution while others believe that structural change can come slowly through political reforms. Some critics believe there are merits in capitalism and wish to balance it with some form of social control, typically through government regulation (e.g. the social market movement).

Prominent among critiques of capitalism are accusations that capitalism is inherently exploitative, alienating, unstable, unsustainable, and creates massive economic inequality, commodifies people, is anti-democratic, leads to an erosion of human rights and national sovereignty while it incentivises imperialist expansion and war, and that it benefits a small minority at the expense of the majority of the population. There are also criticisms from environmental scientists and activists, leftists, degrowthers and others, that it depletes resources, causes climate change, biodiversity loss, topsoil loss, eutrophication, and generates massive amounts of pollution and waste.

A cultivator (also known as a rotavator) is a piece of agricultural equipment used for secondary tillage. One sense of the name refers to frames with teeth (also called shanks) that pierce the soil as they are dragged through it linearly. Another sense of the name also refers to machines that use the rotary motion of disks or teeth to accomplish a similar result, such as a rotary tiller.

Cultivators stir and pulverize the soil, either before planting (to aerate the soil and prepare a smooth, loose seedbed) or after the crop has begun growing (to kill weeds—controlled disturbance of the topsoil close to the crop plants kills the surrounding weeds by uprooting them, burying their leaves to disrupt their photosynthesis or a combination of both). Unlike a harrow, which disturbs the entire surface of the soil, cultivators are designed to disturb the soil in careful patterns, sparing the crop plants but disrupting the weeds.

In classical soil science, humus is the dark organic matter in soil that is formed by the decomposition of plant, microbial and animal matter. It is a kind of soil organic matter with distinct properties due to its high surface area. It is rich in nutrients and retains moisture in the soil, more especially in soils with a sandy texture. Humus is the Latin word for "earth" or "ground".

In agriculture, "humus" sometimes also is used to describe mature or natural compost extracted from a woodland or other spontaneous source for use as a soil conditioner. It is also used to describe a topsoil horizon that contains organic matter (humus type, humus form, or humus profile).

The Dust Bowl was a period of severe dust storms that greatly damaged the ecology and agriculture of the American and Canadian prairies during the 1930s. The phenomenon was caused by a combination of natural factors (severe drought) and human-made factors: a failure to apply dryland farming methods to prevent wind erosion, most notably the destruction of the natural topsoil by settlers in the region. The drought came in three waves: 1934, 1936, and 1939–1940, but some regions of the High Plains experienced drought conditions for as long as eight years. It exacerbated an already existing agricultural recession.

The Dust Bowl has been the subject of many cultural works, including John Steinbeck's 1939 novel The Grapes of Wrath; the Dust Bowl Ballads of Woody Guthrie; and Dorothea Lange's photographs depicting the conditions of migrants, particularly Migrant Mother, taken in 1936.