Spatio-temporal Variability in Soil Macronutrients and Their Relation with Other Soil Properties in a Man-made Wetland of India

Abstract

Present study was carried out to analyze the nutrient status within the surface soils of Bhindawas wetland, a bird and waterfowl paradise, on a temporal scale. Soil organic carbon (%SOC) and total nitrogen (%TN) in the soil varied from 0.079%-2.94% and 0.014%-0.021% respectively. Total phosphorus (%TP) and total potassium (TK) ranged from 0.067 mg/g and 1.16 mg/g to 1.34 mg/g and 4.6 mg/g. C:N ratio showed a large variation from 16.57 to 798.57 along with C:P from 1.68 to 398.5. C:K and N:P showed narrow variation from 0.41% to 19.7% and from 0.03% to 3.13%. Soil parameters like SOC and TN peaked during May whereas TP and TK were higher during or after rains highlighting the impact of hydroperiod on nutrient distribution. Many of the parameters showed significant variations during months. Significant correlations were observed between SOC, TN and TP ensuring that these nutrients had a common origin and were influenced by other physico-chemical properties i.e. pH and bulk density. Analysis revealed that the wetland had both autochthonous and allochthonous inputs that impact nutrient distribution within the wetland. Principal component analysis was used to analyze and amalgamate the temporal variations within the soil nutrients and other parameters. Three principal components were extracted explaining 78.32% of the total variation. Principal components could be characterized as ‘limiting nutrients like TN and TP’, ‘organic carbon and its ratios’ and ‘potassium’. Higher levels of SOC within the wetland soil emphasize its potential as a carbon sink. Carbon sequestration potential of this wetland further accentuates the need for better conservation and management of the wetland.