Healthy soil: Foundation for climate-smart ag in Mekong Delta

Soil determines crop vitality

The Mekong Delta, the country’s largest rice bowl and aquaculture hub, is facing increasingly severe challenges from climate change. Saline intrusion, drought, flooding, land subsidence, and the abnormal emergence of pests and diseases are not only threatening agricultural production but also quietly undermining its most fundamental foundation: cultivated soils.

According to Assoc. Prof. Dr. Nguyen Khoi Nghia, Vice Dean of the Department of Soil Science - College of Agriculture (Can Tho University), the issue of current agricultural land degradation needs to be viewed as an urgent problem because the health of the soil directly determines the productivity, quality of agricultural products, and the crop's ability to withstand harsh climate fluctuations.

Assoc. Prof. Nghia stated that soil is not simply a place for plants to stand firm but also performs many vital functions. Healthy soil creates a stable physical environment that helps the root system anchor deeply and firmly, reducing lodging and enhancing the ability to absorb water and nutrients.

If the soil is degraded, the soil structure is poor, and the soil becomes hard or compacted, the roots cannot develop deeply and cannot anchor firmly. Consequently, the plants are easily prone to lodging, grow poorly, and are susceptible to stress under adverse weather conditions.

Beyond its role as a growing medium, healthy soil is also the "home" to a rich soil organism system. Beneficial microorganisms, fungi, and nematodes participate in bio-chemical cycles, helping to decompose organic matter and release nutrients for crops naturally and sustainably.

Another important function of healthy soil is its ability to regulate water and microclimate. Soil rich in organic matter and having a good structure forms numerous pores, enabling effective water storage and providing continuous water supply to crops throughout the season, and even all year round.

"Under increasingly severe drought conditions, soil with high organic matter content will retain water better, helping crops overcome periods of water scarcity," emphasized Assoc. Prof. Dr. Nguyen Khoi Nghia.

Furthermore, the soil biological system contributes to limiting greenhouse gas emissions, filtering air, and regulating the environment. This is a particularly important factor given the context that agriculture in the Mekong Delta is being oriented towards emission reduction and green growth.

The current reality shows that many agricultural areas in the Mekong Delta are suffering from compaction, nutrient depletion, reduced organic matter, and ecological imbalance due to the long-term overuse of chemical fertilizers and pesticides.

Assoc. Prof. Dr. Nguyen Khoi Nghia warned that soil degradation leads to a cascade of negative consequences: poor crop growth, imbalanced nutrition, increased pest and disease outbreaks, and notably, the accumulation of toxins in the soil environment. When toxins accumulate in the soil, the resulting agricultural products are no longer guaranteed to be safe for consumers, and the situation also has long-term impacts on human health and the living environment.

Climate change exacerbates soil degradation

Climate change is increasing the vulnerability of agricultural land. Saline intrusion introduces sodium ions from seawater into the soil, which breaks down the soil structure, causing the soil to disperse and reducing its capacity for water permeability and gas exchange.

Assoc. Prof. Dr. Nguyen Khoi Nghia analyzed that when soil loses its structure, the surface is easily compacted, and plant roots cannot "breathe," nor can they transport water, nutrients, and oxygen to deeper layers. Concurrently, erratic weather patterns lead to the emergence of new pests, insects, and weeds with increasing density and intensity, compelling farmers to intensify the use of chemical fertilizers and pesticides, inadvertently pushing the soil into a faster cycle of depletion.

Given this reality, Assoc. Prof. Nghia asserts that restoring soil health must become the central focus of agricultural production in the Mekong Delta. Organic agriculture, circular agriculture, and emission reduction are not merely global trends but the inevitable path for soil regeneration.

Increasing the use of organic fertilizers and agricultural by-products, gradually reducing chemical fertilizers and pesticides, combined with proper soil and water management, will help improve soil structure, increase organic matter, and re-establish the biological balance within the soil.

Currently, many farmers in the Mekong Delta have started transitioning to eco-friendly farming models. However, the scale remains small and fragmented, lacking synchronicity, and urgently requires stronger involvement from scientists, management agencies, and appropriate supportive policies.

Amidst increasingly intense climate change, pursuing productivity at all costs is no longer a sustainable option.Healthy soil is the foundation for healthy plants, safe agricultural products, protected environment, and long-term guaranteed livelihoods for farmers.

Assoc. Prof. Dr. Nguyen Khoi Nghia affirmed that investing in soil health today is investing in food security, agricultural product quality, and the sustainable future of the Mekong Delta tomorrow.