The influence of residue quality on soil organic C (SOC) retention has been called into question. A field experiment in Northeast Thailand, which contrasting residues were applied yearly for 13 yr, was used to determine quantities, locations, and stability SOC the matrix identify parameters affecting stabilization a tropical sandy‐textured soil. Total (TOC) content highest intermediate‐quality tamarind ( Tamarindus indica L.) at 3.58 g kg −1 (intermediate N, lignin, polyphenol contents),...

This study aimed to clarify the effects of biochar (BC made from Eucalyptus camaldulensis Dehnh.), and rice (Orysa sativa L.) straw (RS) amendments on soil productivity, carbon sequestration (Cseq) possibility for mitigating greenhouse gas (GHG) emissions. A field trial was conducted with 10 treatments: control, chemical fertilizer (CF) BC or RS each at four rates L (6.25 t/ha), ML (12.50 MH (18.75 t/ha) H (25.00 using a randomized complete block design replicates. The results showed that...

This study investigated the effects of humic acid (HA), flue gas desulfurization gypsum (FG), and their combined application on soil chemical properties, rice yield, phosphorus use efficiency (PUE), agronomic (PAE) during production in acidic paddy soil, which has not been previously studied. A greenhouse experiment was conducted a completely randomized block design with four treatments, including control (no amendments), HA (975 kg ha−1), FG (636 plus FG. increased pH; cation exchange...

Soil capacity as a major carbon (C) sink is influenced by land use. Estimates of soil organic (SOC) sequestration have mostly focused on topsoils [0–30 cm official Intergovernmental Panel Climate Change (IPCC) depth]. We investigated SOC stocks and their quality land-use changes. samples were collected from five depths down to 100 three adjacent fields each representing different use—forest, cassava, rice paddy—in Northeast Thailand. Sequestration in under all uses was higher, indicated...

Organic matter management is believed to solve many of the chemical and physical problems coarse-textured, low fertility soils Northeast Thailand. We tested influence different plant residues available in this area on soil C N dynamics upland (Oxic Paleustult) lowland (Aeric Paleaquult) soils. Residues included groundnut (upland) or Sesbania rostrata stover (lowland), rice straw, Tamarindus indica Dipterocarpus tuber-culatus leaves applied at 10 t ha−1 (dry matter). For former three...

Abstract Particulate organic matter (POM) plays important role in soil carbon (SOC) retention and aggregation. This paper assesses how quality (chemical composition) of four different‐quality residues applied annually to a tropical sandy loam for 10 years has affected POM pools the development aggregates. Water‐stable aggregate size distribution (>2, 0·25–2, 0·106–0·25 mm) was determined through wet sieving. Density fractionation employed determine (light—LF, heavy—HF fractions, 0·05–1...

Cellulose-rich rice straw (RS) decomposes readily in soils, with much of C lost as CO2 and only a small fraction stabilized soil organic carbon (SOC). Additionally, the addition high-energy containing residues may stimulate native SOC decomposition (priming effect, PE) high C/N ratio RS lead to N-mining. We hypothesized that mixing high-C/N low-C/N groundnut stover (GN) would improve chemical composition input, thereby stimulating microbial growth hence increasing retention residue-derived...

Summary Groundnut as a pre‐rice crop is usually harvested 1–2 months before rice transplanting, during which much of legume residue N released could be lost. Our objectives were to investigate the effect mixing groundnut residues (GN, 5 Mg ha −1 ) with straw (RS) in different proportions on: (i) regulating dynamics, (ii) potential microbial interactions decomposition, and (iii) associated nitrous oxide methane emissions at weekly intervals lag phase until transplanting (i, ii) or harvest...

A pot experiment involving growing three consecutive corn crops in two contrasting tropical soils—a coarse-textured, Al-rich Ultisol and a fine-textured, Mn-rich Oxisol—treated with eucalyptus wood biochars—at low (350 °C) high (800 pyrolysis temperatures—at weight per rates of 0%, 1%, 2% 4%, was conducted to assess their effects on the soil organic carbon (SOC) stability (soil C remaining relative initial C) 144 d after biochar application (after third crop harvest). The temperature had...

The ability of biochar applications to alter greenhouse gases (GHGs) (CO, CH, and NO) has been attracting research interest. However, inconsistent published results necessitate further exploration potential influencing factors, including properties, rates, soil textures mineralogy, their interactions. Two short-term laboratory incubations were conducted evaluate the effects different biochars: a with low ash (2.4%) high-volatile matter (VM) (35.8%) contents produced under low-temperature...

Little is known about the carbonaceous greenhouse gases and soil microbial community linked to combination of biochar (BC) rice straw (RS) in paddy soils. The objectives this research were evaluate effects combining BC RS on (1) CH4 CO2 production from soil, (2) archaeal bacterial abundance, (3) grain yield. experiments consisted a pot trial an incubation trial, which had completely randomized design. included five treatments with three replications: (a) control (without BC, RS, chemical...

Intensive use of sandy soils for agriculture leads to significant land degradation. The application locally available organic residues can improve soil fertility, particularly in the context farming practices. This research examined nutrient concentrations with different biochemical compositions/qualities and investigated effects long-term these on nutrients, such as P, K, Ca, Mg, Fe, Mn, Zn, well total carbon (TOC) accumulation tropical soil. A field experiment was conducted Northeast...

Abstract Forms of oxalate in Amaranthus gangeticus L (a vegetable amaranth) grown three sites with different soil and climatic factors were identified, their contents determined. On average the total content was 91 g kg −1 on a dry weight basis. This is high when compared amounts reported to be health hazard other vegetables forage crops. Two dominant fractions amaranth isolated: fraction soluble boiling water which predominantly form potassium magnesium oxalate, an associated insoluble...