Tillage Farming Practices in Thailand and Environmental Consequences

Tillage in farming practises in Thailand plays a critical role in improving soil health and crop development, especially in Thailand’s sugarcane industry. Farmers have long utilized tillage to break down the soil into smaller pieces, promoting better crop growth. It modifies the soil structure, enhancing the topsoil’s ability to absorb fertilizers. Tillage also helps crops by making it easier for their roots to access essential nutrients and water. Sugarcane, like most crops in Thailand, benefits from this process. This article will explore the tillage farming practices in Thailand sugarcane industry and their environmental impact.

In 2020, Thai farmers grew more than 10,000,000 rai (1,600,000 hectares) of sugarcane across 47 provinces. Due to varying practices and climates, the sugarcane production cycle differs by region. Planting occurs at three distinct times:

• Before the rainy season in irrigated areas, between February and April
• Before the rainy season in rainfed areas, between April and June
• After the rainy season, from October to December

Despite varying planting times, tillage occurs at least twice each crop year: once at the beginning of the planting cycle, and again 3-4 months after planting, when fertilizer is applied. The second tillage improves nutrient penetration, making it easier for sugarcane roots to absorb the fertilizer.

Figure 1: Examples of tractor tilling in sugarcane fields

The issues with tillage farming practises in Thailand

Soil Degradation from Over-Tillage

Tillage in farming practices in Thailand offers benefits, particularly in crop cultivation, but recent studies reveal the risks of over-tilling, especially from a sustainability standpoint. Tillage can fracture the soil structure, leading to surface runoff, soil dryness, erosion, acidification, and a decrease in organic content. Over time, tillage accelerates these processes, significantly affecting soil health.

Soil Acidification Process from Tillage Farming Practices in Thailand

Soil acidity increases as a result of tillage. During the rainy season, water and carbon dioxide mix to form carbonic acid. This acid breaks down into hydrogen ions (H+), which, when present in high quantities, make the soil more acidic. As soil acidity rises, essential nutrients such as calcium and magnesium are pushed out, leaving the soil more depleted.

Decline in Organic Content

Tillage also reduces organic content in the soil. The practice disturbs crop residues and destroys the vegetal cover. Organic matter, plants, bacteria, and fungi within the soil consume carbon and release nutrients essential for plant growth. Tillage disrupts this cycle, decreasing natural nutrients in the soil and releasing carbon dioxide into the atmosphere. The loss of the vegetative layer also weakens the land’s protection against wind and water, leading to substantial soil erosion.

The No-Till Farming Solution to Tillage Farming Practices in Thailand

To mitigate these issues, no-till farming has emerged as an alternative. This method preserves vegetal cover and organic matter, providing multiple benefits. Superficial vegetation helps retain moisture in the soil, slowing evaporation when it rains. Consequently, no-till land retains water more effectively, leading to higher yields during hot, dry periods. Additionally, crops grown in no-tilled soil benefit from nutrient-rich conditions. Farmers require fewer fertilizers, reducing costs and limiting chemical inputs that contribute to greenhouse gas emissions (see our article Chemical Fertilizer in Agriculture: A Big Source of Greenhouse Gas Emissions).

Environmental and Economic Benefits of No-Till over Tillage Farming Practices in Thailand

Studies show that no-till land, especially when combined with organic fertilizers, can increase soil organic matter by 9% in two years and by 21% within six years. This practice improves the environmental footprint by reducing greenhouse gas emissions and sequestering more carbon. The combined use of no-till farming and organic fertilizers also enhances soil biodiversity. Furthermore, no-till farming has economic benefits, as it eliminates the need for costly tillage equipment, which can cost up to 30,000 THB, a significant expense for smallholder farmers.

A Necessary Shift for Sustainable Agriculture

Tillage in Thai farming has been a long-standing practice. However, the environmental crisis compels agricultural stakeholders to rethink production methods and explore innovative solutions for a more sustainable future. Transitioning to no-till farming will be challenging but essential for the long-term health of the land.