Effect of Different Land Use Systems on Major Nutrient Status in Soils of Westernghat-Chikamagalur, Karnataka, India

Abstract

The present study was conducted to assess the impact of different land-use systems on major nutrient status viz: Nitrogen, Phosphorus and Potassium in soils of central part of Western ghat, Karnataka. The land use types include both manmade systems (Agriculture: paddy; Horticulture: coffee, are canut, tea and banana); forest plantation (accacia and teak) and natural systems (Evergreen, semi-evergreen and grassland). In each land use systems, samples were collected from two depths (0-15 cm and 15-30 cm) at 20 locations during pre-monsoon and post monsoon period. Soil samples were analyzed for available nitrogen, available phosphorus and available potassium. The results revealed that available nitrogen content in surface soil was significantly higher (394.55 kg ha -1 ) than that of subsurface soil (330.57 kg ha -1 ). Among manmade land use systems, available nitrogen content was significantly higher in coffee (435.82 kg ha -1 ) followed by in soils under banana 404.40 kg ha -1 . Similarly, natural system the available-N content was in the range of 294.97 to 376.55 kg ha -1 with minimum in grassland and maximum in semi-evergreen forest. Available-P varied significantly among different land use systems. The highest available-P content was recorded in soils under coffee (29.31 kg ha -1 ) followed by evergreen forest (28.37 kg ha -1 ), semi-evergreen (27.26 kg ha -1 ) and other systems. The available-P was least in grassland (20.28 kg ha -1 ). The available K 2 O content in soils under paddy was 299.42 kg ha -1 and it was significantly lower than other systems but was at par with those observed in grassland (311.01 kg ha -1 ), acacia (321.01 kg ha -1 ) and teak system (329.86 kg ha -1 ). These results are indicated that well-managed horticultural system in general and coffee in particular had better soil fertility which is comparable to that found in natural forest system.

Vertical distribution of soil chemical properties under different land use systems of Biligirirangana Hills, Karnataka

“…The amount so ixed along N derived from mineralization might be suf icient to replace the N removed through the litter. These results are in accordance with Shivakumar et al (2020) who reported that higher available N content under natural systems namely evergreen and semievergreen compared to forest plantation systems viz., teak and acacia might be attributed to the variation in quality and quantity of litter as it is derived from mixed vegetation type under natural system. Further, the removal of vegetation by livestock grazing and exposure of soil surface may impact on the surface runoff due to direct drop of rainfall under agricultural land use system, which can remove the animal and plant residues from the surface soil layer thereby causing nitrogen depletion.…”

“…Similarly, Nigussie and Kissi (2012) (275.97 kg ha ) which may be attributed to the accumulation of more organic matter on the surface layer and its subsequent decomposition than the subsurface soil layer. These results are in conformity with the results obtained by Shivakumar (2020) explaining the presence of higher available nitrogen content in the surface layer than that of the subsurface layer of different LUSs. The contents of available nitrogen were strongly associated (r =0.875*) with soil organic carbon in all the depths and decreased consistently with increasing soil depth under all LUSs (Table 6).…”

“…The accumulation of organic matter in soils is the result of a balance between residue input rates and net decomposition rates as affected by soil temperature and moisture conditions (Murage et al, 2007). These results are corroborated by the indings of Shivakumar et al (2020). Islam and Well (2000) reported that lower SOC in soil under paddy might be attributed to an imbalance in C input and output in the system.…”

“…Higher CEC of soil was recorded in the surface depth of natural forest and tree-based LUSs compare to agricultural LUSs, which might be due to high exchangeable bases and organic carbon resultin in the dissociation of its functional groups which providing more negative charges (Das et al, 2023: Karthika et al (2020). Shivakumar et al (2020) reported that CEC of soil under the coffee system was signi icantly higher as compared to paddy LUSs. Das et al, 2023 andShivakumar et al (2020) observed a decline of CEC with soil depth along with a decline in SOM but unchanged clay content and composition.…”

Assessment of land use systems for CO2 sequestration, carbon credit potential, and income security in Vindhyan region, India

“…It is clear from Figure 4 that all the LUSs accumulated higher biomass owing to greater NPK‐rich leaf surface area which in turn deposited in the soil after fall down and thus releases more NPK in soil upon their mineralization. Shivakumar et al (2020) reported that forest LUS has a higher amount of available NPK than other LUSs. In the present study, a higher NPK level was recorded in the TBFLUS which might be attributed to the humification process that led to higher OC content along with the presence of leaf litter in the surface soil.…”