Land Use, Landform, and Soil Management as Determinants of Soil Physicochemical Properties and Microbial Abundance of Lower Brahmaputra Valley, India

Abstract

Due to the shifting course of the Brahmaputra River, the fluvial landforms of the Brahmaputra Valley of Assam, India, are prone to changes in landform and land use. For sustainable soil management under such conditions, it is crucial to have information about soil physicochemical and biological properties for different land uses. Therefore, the present study was conducted to investigate the soil physicochemical properties and soil microbial population across five major land uses under different landforms, such as paddy fields, banana systems, and arecanut cultivations in the alluvial plains; and rubber plantations and sal forests in the uplands, with varying slope gradients and soil depths (0–25 cm and 25–50 cm) in the lower Brahmaputra Valley. The results of the analysis of variance revealed that the effects of different landforms and land uses were found to be statistically significant on very labile soil organic carbon (VLSOC), available K, B, Fe, Mn, Zn, and Cu, and soil moisture content across two different soil depths. Paddy cultivated systems recorded the highest (1.23%) soil organic carbon (SOC), but these levels were statistically at par with other land use scenarios except for banana systems; whereas, forests and rubber plantations showed the highest VLSOC (0.38% and 0.34%, respectively,) and were significantly different from other land use scenarios. All soil microbial populations (bacteria, fungi, and actinomycetes) studied varied significantly in different land uses across varying soil depths. Perennial land uses under arecanut, rubber, and forest cultivations showed significantly higher microbial populations than paddy and banana systems. The principal component analysis (PCA) identified SOC, VLSOC, Cu, K, B, P, and the bacteria count as the major soil quality parameters of the study area. The results showed that landforms, land use, and management practices collectively affect soil properties. Therefore, soil management choices should take into consideration the landforms and land use for maintaining soil health and its sustainability.

Soil Quality Indicators under Different Smallholder Managed Cropping and Landuse Practices in Abuja, Nigeria

“…Tellen & Yerima (2019) describe the chemical fertilizers and weedicides used for soil fertility maintenance in the area as typically containing some high amounts of cations, which could help to balance out the negative charges lost from the soil's exchange complex of cultivated soils as losses occur due to processes such as sheet erosion induced by high tillage and weeding frequencies and low organic matter in the control and the five cropping plots. The range in value of the property in the study area is not very wide, with the lowest being about 5.3 and the highest being about 6.9; however, the fact that the pH values of the cropping plots are significantly lower than those of the control is an indication of the fact that losses of cations have been occurring from the soils of the cultivated plots, which is very much in agreement with the findings of many research workers (Sadiq et al, 2021;Tumayro & Tesgaye, 2021;Haile et al, 2022;Hota et al, 2022). This suggests that where effective soil fertility amendments are introduced, declines in pH level cannot only be minimized but even be reversed.…”

“…In the literature, substantial research information is available on the effects of various CLUPs on SOC, TN, and pH, but the findings across different landscapes are still controversial. Many researchers (for example, Abbasi et al, 2007;Abad et al, 2014;Takele et al, 2014;Bore et al, 2015;Dengiz et al, 2015;Kalu et al, 2015;Chemada et al, 2017;Olorunfemi et al, 2018;Galindo et al, 2022;Paramesh et al, 2022;Shi et al, 2010;Wang et al, 2021;and Hota et al, 2022) observed that paddy rice had a higher SOC content than forested soil, while Jonczak (2013) found out that fallow land had a higher SOC content than forested soil. Pham et al (2018b), on the other hand, found that soils under planted acacia and rubber forest covers and arable land had higher SOC levels than those under natural forest, while Mengistu et al (2022) observed that the SOC values of soils under cropland and Eucalyptus camaldulensis planted fallows are not significantly different from each other.…”

Impact of Agricultural Land Use Types on Soil Moisture Retention of Loamy Soils

“…Adaptation to the increased extremities of hydrologic phenomena (droughts and floods) and the retention of water are indispensable in light of climate change [16]. Therefore, analyzing the suitability of soil textural types, fertility, topography and crop varieties may increase the profitability of the given land use type if managed site-specifically [17][18][19][20].…”

Assessing the Underlying Drivers of Change over Two Decades of Land Use and Land Cover Dynamics along the Standard Gauge Railway Corridor, Kenya

“…The construction of infrastructure such as roads and railways together with the associated urban development often results in landscape modifications and changes in human activities in the areas where they traverse [7][8][9][10]. The LULC changes lead to deforestation, water scarcity, loss of biodiversity [11,12] and water pollution [13]. While social development and poverty reduction are key objectives of many development corridors; Hope and Cox (2015) observed that less attention has been given to impacts on natural capital (e.g., water, forests, and other key biodiversity areas) which directly impact local livelihoods [14].…”