The sustem in which a farmer uses a piece of land for a period and abandons it f...

The question is asking about a farming system where a farmer uses a piece of land for a period and then moves on to another land. This system is called shifting cultivation.

Shifting cultivation is a traditional agricultural practice in which farmers clear a piece of land, cultivate it for a few years, and then abandon it to allow the land to regenerate. They then move on to a new piece of land and repeat the process. This cycle continues, with the farmer rotating between different plots of land.

The purpose of shifting cultivation is to give the land a chance to recover and regain its fertility. By allowing the land to rest and regenerate, the farmer can continue to have productive agricultural land without depleting its resources.

Crop rotation, on the other hand, refers to the practice of growing different crops on the same piece of land in a planned sequence. This helps to prevent the buildup of pests and diseases, improves soil fertility, and reduces the need for chemical fertilizers and pesticides.

Mix cropping, also known as intercropping, involves growing two or more different crops together in the same field at the same time. This practice maximizes the use of land, sunlight, and nutrients, and can provide additional benefits such as pest control and soil conservation.

Ley farming is a system where pastures or meadows are periodically plowed and planted with crops for a few years before being returned to grassland or pasture. This helps to maintain the productivity of the land and provide a balance between crop production and animal grazing.

Therefore, the correct answer to the question is shifting cultivation, as it describes the specific farming system in which a farmer uses a piece of land for a period and then abandons it for another land.