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Soils with Physical Problems
Published in Manorama K.C. Thampatti, Problem Soils, 2023
Addition of plant residues is very important for regeneration and maintenance of soil structure in the transplanted rice ecosystem, but for various reasons, the amount of residue being returned to the soil is inadequate. The added organic matter will improve soil physical health, and helps nutrient retention, improve soil biological activity and improve crop production.
Qualitative and Quantitative Analysis of Water
Published in Sreedevi Upadhyayula, Amita Chaudhary, Advanced Materials and Technologies for Wastewater Treatment, 2021
BOD is measured by comparing the DO levels of a water sample before and after five days of incubation in the dark. The BOD requirement for different samples are tabulated in Table 2.3. One liter of water sample is used for measuring the amount of molecular oxygen required to convert organic molecules into carbon dioxide. Organic matter comes from dead leaves, animals, and microorganisms, sewage, etc.
Wastewater Spawned Infectious Disease
Published in Frank R. Spellman, Fundamentals of Wastewater-Based Epidemiology, 2021
Bacteria and other microorganisms use the organic matter as a food source. They use oxygen (aerobic decomposition), organic matter and nutrients to produce carbon dioxide, water, and stable solids, which may settle out, and more organisms. Carbon dioxide is an essential component of the photosynthesis process occurring near the surface of the pond. Organisms also use the solids that settled out as food material; however, the oxygen levels at the bottom of the pond are extremely low so the process used is anaerobic decomposition. The organisms use the organic matter to produce gases (hydrogen sulfide, methane, etc.) which are dissolved in the water, stable solids, and more organisms. Near the surface of the pond a population of green algae will develop which can use the carbon dioxide produced by the bacterial population, nutrients, and sunlight to produce more algae and oxygen which is dissolved into the water. The dissolved oxygen is then used by organisms in the aerobic decomposition process.
Geomechanical Characterization of Experimental Mud Bricks from La Joya Archaeological Site: Effect of the Addition of Additives on Their Mechanical Properties
Published in International Journal of Architectural Heritage, 2023
Jhonny Peraza-Gongora, Carlos Rolando Rios-Soberanis, Annick Jo Elvire Daneels Verriest, Jose Rodriguez-Laviada
Organic carbon and inorganic carbon (CaCO3) were measured in soil samples using a HiperToc solid analyser from Thermo Scientific. The abundance of organic matter is measured by estimating the loss on ignition at 550°C. Total organic carbon is determined by the amount of carbon dioxide that is generated by oxidizing organic matter under special conditions. A typical TOC analysis measures both total carbon (TC) present and total inorganic carbon (TIC). Subtracting the total carbon from the total inorganic carbon, the total organic carbon is obtained. The relationship is represented by the expression TOC = TC – IC. Soil separation was performed in a particle size fraction <2 µm in all samples, and in one sample the separation was carried out in 3 sub-fractions (4–2 µm; 2–0.5 µm and <0.5 µm) for a detailed identification of the clay fraction.
Investigation of natural dewatering of dredged sediments incorporating evaporation and drainage
Published in Drying Technology, 2023
Ali Hussan, Daniel Levacher, Salim Mezazigh
Organic matter in soils is a complex mixture of decomposed plant and animal remains, substances synthesized by biological or chemical means from decomposition products, plant, and animal secretions, and their decomposition products.[53] This study attempts to comprehend the effects of organic matter content on the permeability of sediments by examining two types of sediments with varying organic matter percentages. The sediments with a higher percentage of organic matter, i.e. CHER-ALL, have a relatively higher permeability compared to MOR-ALL, although the clay content in both sediments is nearly identical. In the first 16 h, up to 37% of the total water was drained from CHER- ALL sediments as compared to around 20% for MOR-ALL sediments. These results could be verified from the past published data. For example, Malkawi,[53] investigated the effects of organic matter on the physical and physicochemical properties of illitic soils by combining organic matter with inorganic illitic clayey soil at eight different levels. The findings of this study revealed that at low organic content, soil particles tend to aggregate, whereas at higher organic content, soil particles tend to disperse, and this dispersion of soil particles may result in an increase in permeability. Al Rawi[54] investigated the fine-grained clayey soil from Amman, Jordan, and discovered that the higher the organic matter content in the soil, the greater its permeability.
Removal efficiency of dissolved organic matter from secondary effluent by coagulation-flocculation processes
Published in Journal of Environmental Science and Health, Part A, 2020
Natália Rodrigues Guimarães, Fabiane Dörr, Rodrigo de Oliveira Marques, Ernani Pinto, Sidney Seckler Ferreira Filho
During the biological treatment, microorganisms convert the organic matter present in the wastewater into biomass, carbon dioxide, water, and organic by-products.[2] This effluent is a complex matrix containing a variety of soluble organic compounds, including influent substrate slowly or non-biodegradable, and intermediates and final products of substrate degradation. In a more specific analysis, the effluent from the biological treatment consists of: (1) organic compounds called refractory natural matter from drinking water; (2) synthetic traces of organic compounds generated during the household water; (3) products of the disinfection treatment of water; and (4) soluble microbial products derived from biological wastewater treatments.[3]