Terrace Farming – A Method to Control Soil Erosion in India

Table of Contents

• Introduction
• What is Terrace Farming
• Types of Terrace Farming
• Methods of Terrace Farming
  • Bench Terracing
  • Contour Terracing
  • Parallel Terracing
• Benefits of Terrace Farming
• How Terracing Help Reduce Soil Erosion

Introduction

Terrace farming or terrace cultivation is an age-old farming practice. The two ancient civilizations renowned for practising it are the Inca Civilization of South America and the Cordillera tribe of The Philippines. It is not unknown to India. In India, the people living in hilly areas of Uttarakhand, Himachal Pradesh, and Northeast states mainly practice this type of farming.

What is Terrace Farming?

Terrace farming is a method of growing crops on the hillsides by planting them on terraces (flat areas or farmlands) created through cutting of the slopes. These terraces resemble a series of steps, so it is also known as step farming.

Terrace cultivation is one of India's most practised types of agriculture in hilly regions. The main areas where it is practised in India are Kashmir Valley and Northeast, the Himalayan regions, and certain areas of the Western Ghats.

Some of the crop examples under terrace agriculture are:

• Rice and wheat
• Maize and barley
• Pulses and millets
• Tea and coffee
• Vegetables and fruits
• Spices

Types of Terrace Farming in India

• Broad-base terraces: These have ridges with a broader base and a gentler slope. They are designed to reduce soil erosion by slowing down the water flow. These are of two types:

1. 1. Graded terraces: Also known as drainage terraces, they are ideal in areas with more than 600 mm of rainfall. They have a slight slope to remove the excess water runoff and protect the crop from waterlogging.
   2. Level terraces: Also known as ridge terraces, they are prevalent in India as contour bunds. They have a narrow width of 1.2 – 2.5 meters.

• Bench terraces: They are constructed in hilly areas with a slope range of 15 – 30% and a medium to high degree of soil erosion. They are further classified into:

1. 1. Levelled and Tabletop terraces: These terraces are constructed for crops requiring a large quantity of water, such as paddy. To facilitate uniform ponding of water on farmland, they are ideal for lands with slopes ranging from 1 – 6%.
   2. Outward sloping terraces: These are ideal for hilly areas where soil depth is inadequate for levelling work, rainfall is scanty, and soil erosion is insignificant.
   3. Inward sloping terraces: These terraces are fit for hilly areas with deep permeable soil and heavy rainfall. They are ideal for growing crops like potatoes.

• Stone terraces: In some regions, stone walls are constructed to support the terraces. These terraces help retain the soil and slow down water runoff.

Methods of Terrace Farming

Broadly, there are three terrace farming methods: Bench Terracing, Contour Terracing, and Parallel Terracing.

Bench Terracing

Bench terracing is a method of creating a series of steps called "benches" by cutting the slopes of the hill. The benches are flat areas that look like staircases.

The main goal of this method is to reduce the slope of the hillside to reduce the velocity of water runoff and thus prevent soil erosion. However, constructing such terraces is costly.

The main components of bench terracing are:

• Terrace bench
• Riser slope
• Shoulder bund

The bench terracing can be further classified into hill-type bench terraces, irrigated bench terraces, and orchard bench terraces. Further, bench terracing is ideal for growing crops like paddy and potatoes.

Contour Terracing

In this method, terraces are constructed along the natural contour lines of the hill slopes. They help decelerate the water flow down the slopes. It is also called contour ploughing.

To construct such terraces, contour lines are mapped that follows the natural relief of the hill slopes. The contours are lined with geotextiles and filled with rock, stacked, or placed to form a structure resistant to soil erosion. These terraces comprise pointed rows and grassed waterways.

Further, this method has ditches and ridges running perpendicular to the hill slope. They follow the hillside's natural shape. Thus, they do not alter the landscape as compared to bench terracing.

Parallel Terracing

Parallel terracing is the easiest way to cultivate land as it eliminates the need for contour lines, as in contour terracing.

In this method, the terraces are constructed parallel to each other and are in the direction of field operation.

Further, the parallel terraces can have a gentle slope or flat-like benches.

Benefits of Terrace Farming

• They help prevent soil erosion in hilly areas by reducing the slope.
• They help conserve water and protect the water quality.
• They create additional arable land in hilly areas where the availability of flat land is limited.
• Terraces, by supporting the cultivation of different crops, can help promote biodiversity.
• They allow efficient use of water to promote sustainable agricultural practices.
• They improve crop yield by conserving soil and water.

How Terracing Help Reduce Soil Erosion?

Terracing is an effective method to reduce soil erosion in hilly areas. Terraces act as land intercepts and reduce the slopes of the hill. The hilly regions remain more levelled with terraces. As a result, the velocity of water runoff and sediment transportation is reduced. These two together help control soil erosion.