Soil Physio-Chemical Variations in Monocropping and Mixed Cropping Systems; A Case Study from Kollam District, Kerala, India

Abstract

Introduction: A study was conducted to examine the physio-chemical properties of soil in monocropping and mixed cropping agricultural areas in Kollam district, Kerala, India. The monocropping area, located in Perinad in the district focused on cultivating Citrus limon (lemon), while the mixed cropping area in Anchalummodu involved in the cultivation of various vegetable crops.

Objectives: Study aims to examine the effects of monocropping and mixed cropping on soil characteristics and to enhance the understanding of how monocropping and mixed cropping systems impact on soil health.

Methods: This study was conducted in two agricultural locations within the Kollam district of Kerala state to compare soil characteristics between monocropping and mixed cropping systems. Soil samples were collected from both areas at two depths (0–15 cm and 15–30 cm) from selected sample plots. Standardized laboratory procedures were followed to ensure accuracy and reliability in the analysis of physical and chemical properties of the soil, including soil pH, soil electrical conductivity (EC), soil moisture content, soil water-holding capacity, soil organic carbon, soil available phosphorus, soil potassium, soil sulphur, and soil micronutrient levels (iron, zinc, copper, manganese, and boron). The collected data were statistically analysed and correlation analysis was used to examine the relationships between different soil parameters.

Results: The results of the present investigation showed that in mixed cropping area soils maintained a more stable pH range (6.20–6.30) compared to monocropping systems (6.02–6.13), thereby enhancing nutrient availability. Although soil moisture content and water-holding capacity were slightly higher in monocropping soils, but mixed cropping demonstrated improved nutrient cycling. Mixed cropped soils also exhibited higher concentrations of essential micronutrients such as manganese (40 ppm vs. 8 ppm), zinc (16.72 ppm vs. 12.64 ppm), and copper (6.6 ppm vs. 3.4 ppm) in the upper soil layer, indicating better soil health. The distribution patterns of potassium and sulphur varied depending on soil depth and cropping system. Correlation analysis revealed significant relationships between soil parameters, soil pH showing a negative correlation with moisture content, organic carbon, and potassium. Overall, the findings highlight the advantages of mixed cropping in sustaining soil fertility and maintaining balanced nutrient levels, thereby supporting sustainable agricultural practices.

Conclusions: The study highlights potential issues associated with monocropping, such as soil nutrient imbalances, which could lead to long-term soil degradation. The higher sulphur content and uneven potassium distribution observed in monocropping soils underscore the need for careful nutrient management. While both cropping systems offer certain advantages, the present study suggests that mixed cropping may provide greater long-term benefits for soil health and sustainability, particularly in maintaining a balanced nutrient profile and enhancing soil structure.