contour farming:
Contour farming has been practiced for centuries in parts of the world where irrigation farming is important. Although in the United States the technique was first practiced at the turn of the 19th century, straight-line planting in rows parallel to field boundaries and regardless of slopes long remained the prevalent method. Efforts by the U.S. Soil Conservation Service to promote contouring in the 1930s as an essential part of erosion control eventually led to its widespread adoption.
The chlorophyta are important FOR PROVIDING OXYGEN TO THE ATMOSPHERE.
Chlorophyta refers to the division of lower plants, which is made up of green algae. The plants are aquatic and they found majorly in fresh water and marine habitats, although some are found living on land. Chlorophyta serve as an important source of food to marine organisms and they play a very significant role in contributing to the world's supply of oxygen through the process of photosynthesis.
