SOIL ORGANIC MATTER (SOM): STATUS, TARGET AND CHALLENGES IN NEPAL

Abstract

Changes in soil organic matter (SOM) are slow and difficult to monitor, usually apparent after few decades. Recent changes in the agriculture had its influence on soil, including the soil organic matter content. About 60% of soil in Nepal now have low organic matter content. Agriculture Perspective Plan (APP) was focused more on the concept of green revolution to increase the chemical fertilizer inputs, however, the scenario is changing. Use of organic fertilizers is promoted extensively by government and different organizations with a target of increasing SOM content from 1.92% in 2015 to 4% by 2035. This paper aims at analysing the current status, targeted goal and the challenges faced in the augmentation of the soil organic matter using data available. Achieving this target requires an addition of extra 2.244 ton/ha of organic matter on a yearly basis for 20 years. The average amount of organic matter (2.5-3 ton/ha) applied is lesser than a single season grain harvest. 4.69% of sites had high soil organic matter in fiscal year 075/76 which slipped to 2.64% in 2076/77. The sites with low soil organic matter increased from 12.73% to 15.31%. The causes behind the SOM decline varies according to different agro-ecological zones like soil erosion, residue burning, imbalanced fertilizer use, defective FYM production etc. Findings suggest precise technologies required to be adopted to tackle with the different niche specific causes of soil fertility decline. Despite the complete nutrient content, bulky nature of organic fertilizers sets a major drawback regarding their transportation, distribution and commercialization. Government of Nepal is promoting organic fertilizer use by subsidizing their production cost by 50%. Following integrated nutrient management (INM) techniques, sustainable soil management practices (SSMP) and promotion of use of locally available resources can play a huge role in making the technology sustainable to the farmers.

Keywords

• soil organic carbon
• soil health
• food security