Assessment and Mapping soil fertility status of Potato Super Zone, Kavrepalanchowk

Potato is a staple food crop in high hills and mountains and a major vegetable throughout the country and one of the most important cash generating crops in Nepal. With the efforts undertaken by research and extension sectors, its productivity has significantly increased in last twenty years. However, this is not sufficient for increasing population of the country. Considering its potentiality for income, employment, industrial products, export and processing, appropriate technologies are urgent.Soil fertility evaluation is the most basic decision making tool for the sustainable soil nutrient management. Soil fertility studies and mapping is an effective way to diagnose soil status and recommend as per the need of the nutrient to particular crop in the area. This research aims to assess and prepare soil nutrient map of potato super zone, Kavrepalanchowk in Nepal. The specific objectives of the research were to assess soil texture, pH and organic matter status and simultaneously prepare soil fertility map of the potato super zone. A total of 202 soil samples were collected and nutrients were analyzed using standard procedure in the soil laboratory. Composite soil samples were collected from 6 to 10 different spots of the area at 0-20 cm depth by using soil auger. The GPS location of each soil sampling point was noted. The soil sampling point of each zone was determined by studying various aspects (area, slope, colour, texture, etc.) of the study area. Based on the nutrient status, nutrient maps were prepared and presented. Soil fertility maps were prepared by observing the critical nutrients required for the specific crops and by giving those nutrients certain ranking based on the nutrients role for the crop. The soil of Potato super zone was mostly found to be silty loam, moderately acidic (pH 5.9), medium in organic matter content (2.67%) and total nitrogen (0.13%), high in available phosphorus content (56 kg/ha) and available potassium (356kg/ha). There is also sandy loam, loam and silty clay loam types of soil in the area. Soil fertility maps were prepared by setting criteria based on nutrient status that were tested in the laboratory and on the basis of nutrients that are critical for each crops of the super zones. Vegetable super zone soil was found having medium (50%) and high (30%) fertility status. Based on the soil analysis report, it could be concluded that the soils of potato super zone is fair enough for cultivating potato crop at the moment.