Red soil

About: Red soil is a research topic. Over the lifetime, 2070 publications have been published within this topic receiving 19910 citations. The topic is also known as: Red soils.

Influence of sugarcane bagasse-derived biochar application on nitrate leaching in calcaric dark red soil.

Abstract: Application of biochar has been suggested to improve water- and fertilizer-retaining capacity of agricultural soil. The objective of this study was to evaluate the effects of bagasse charcoal (sugarcane [ L.] bagasse-derived biochar) on nitrate (NO) leaching from Shimajiri Maji soil, which has low water- and fertilizer-retaining capacity. The nitrate adsorption properties of bagasse charcoal formed at five pyrolysis temperatures (400-800° C) were investigated to select the most suitable bagasse charcoal for NO adsorption. Nitrate was able to adsorb onto the bagasse charcoal formed at pyrolysis temperatures of 700 to 800° C. Nitrate adsorption by bagasse charcoal (formed at 800° C) that passed through a 2-mm sieve was in a state of nonequilibrium even at 20 h after the addition of 20 mg N L KNO solution. Measurements suggested that the saturated and unsaturated hydraulic conductivity of bagasse charcoal (800° C)-amended soils are affected by changes in soil tortuosity and porosity and the presence of meso- and micropores in the bagasse charcoal, which did not contribute to soil water transfer. In NO leaching studies using bagasse charcoal (800° C)-amended soils with different charcoal contents (0-10% [w/w]), the maximum concentration of NO in effluents from bagasse charcoal-amended soil columns was approximately 5% less than that from a nonamended soil column because of NO adsorption by bagasse charcoal (800° C). We conclude that application of bagasse charcoal (800°C) to the soil will increase the residence time of NO in the root zone of crops and provide greater opportunity for crops to absorb NO.

Soil carbon sequestration in China through agricultural intensification, and restoration of degraded and desertified ecosystems

Abstract: The industrial emission of carbon (C) in China in 2000 was about 1 Pg yr−1, which may surpass that of the United States (1ċ84 Pg C) by 2020. China's large land area, similar in size to that of the United States, comprises 124 Mha of cropland, 400 Mha of grazing land and 134 Mha of forestland. Terrestrial C pool of China comprises about 35–60 Pg in the forest and 120–186 Pg in soils. Soil degradation is a major issue affecting 145 Mha by different degradative processes, of which 126 Mha are prone to accelerated soil erosion. Total annual loss by erosion is estimated at 5ċ5 Pg of soil and 15ċ9 Tg of soil organic carbon (SOC). Erosion-induced emission of C into the atmosphere may be 32–64 Tg yr−1. The SOC pool progressively declined from the 1930s to 1980s in soils of northern China and slightly increased in those of southern China because of change in land use. Management practices that lead to depletion of the SOC stock are cultivation of upland soils, negative nutrient balance in cropland, residue removal, and soil degradation by accelerated soil erosion and salinization and the like. Agricultural practices that enhance the SOC stock include conversion of upland to rice paddies, integrated nutrient management based on liberal use of biosolids and compost, crop rotations that return large quantities of biomass, and conservation-effective systems. Adoption of recommended management practices can increase SOC concentration in puddled soil, red soil, loess soils, and salt-affected soils. In addition, soil restoration has a potential to sequester SOC. Total potential of soil C sequestration in China is 105–198 Tg C yr−1 of SOC and 7–138 Tg C yr−1 for soil inorganic carbon (SIC). The accumulative potential of soil C sequestration of 11 Pg at an average rate of 224 Tg yr−1 may be realized by 2050. Soil C sequestration potential can offset about 20 per cent of the annual industrial emissions in China. Copyright © 2002 John Wiley & Sons, Ltd.

Biochar from water hyacinth (Eichornia crassipes) and its impact on soil biological activity

Abstract: Biochar is a useful material for carbon storage in soils. In this report, we explored conversion of water hyacinth (Eichornia crassipes) to biochar as a sustainable weed management strategy, as it also has potential for improving soil quality. Eichornia biomass samples were carbonised with limited supply of air in a muffle furnace at varied temperature (200 to 500 °C) and residence time (30 to 120 min). The biochar yield decreased with temperature and time, but biochar carbon stability increased with temperature. The optimum condition for obtaining maximum stable carbon in Eichornia biochar (EBC) is 300–350 °C temperature with 30–40 min residence time. TGA and FTIR studies showed that EBC has increased aromaticity and carbon stability compared to the starting biomass. Impact of the EBC on soil quality was studied using a red soil, from Dhanbad, India. Soil biochemical properties (dehydrogenase, fluorescein hydrolases, catalase, respiration, active microbial biomass) and maize seedling growth were used to investigate the effects of biochar addition to the soil. Maize seedling vigour index increased from 1.0 at control to 1.61 in 20 g/kg EBC treatment. The maximum increase in soil enzymes like acid phosphatase activity (+ 32%), alkaline phosphatase activity (+ 22.8%), and fluorescein hydrolases activity (50%) occurred at the EBC dose of 20 g/kg. EBC significantly enhanced the soil biological activity particularly the active microbial biomass which has increased by 3 times and soil respiration by 1.9 times. The study shows that the waste Eichornia weed could be gainfully utilised as a soil quality amendment material by converting it to EBC.