A major environmental problem caused by using the agricultural practice of tilling is

Tilling breaks the natural structure of the ground by exposing the organic matter, accelerates mineralization, and pollutes.

Explanation:

Organic matter, together with porosity and humidity directly influence in the recovery of the soil structure and stability when these are exposed to different mechanical treatments or actions. Porosity and soil matrix continuity directly influence in the hydraulic conductivity and interchange water and air processes.

Tilling systems affect the productivity of the crops, and the physic, chemical and hydraulic characteristics of the soil. Tilling modifies the superficial layer of soil, alters the continuity of porosity and reduces the amount of organic matter in the ground.

Intensive use of tilling contributes severely to the carbon emission. Carbon is stored in the soil and when this last one is altered by tilling, carbon is exposed and released out in the open, becoming CO². This gas is one of the gases of the greenhouse effect and one of the causes of global warming.

Intense tilling breaks the natural structure of the ground by exposes the organic matter, it accelerates mineralization, and it pollutes.