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Desertification Vulnerability Assessment
Published in Ajai, Rimjhim Bhatnagar, Desertification and Land Degradation, 2022
In the long term, vegetation increases the soil-aggregate stability and cohesion as well as improves water infiltration. Mathematically, this relationship is termed as a negative exponential curve between vegetation cover and erosion rates, as expressed by Equation 10.7: SLr=e−bC
Compost utilization in ornamental and nursery crop production
Published in Monica Ozores-Hampton, Compost Utilization in Production of Horticultural Crops, 2021
Compost additions to soil bring biological, chemical and physical benefits. Some of the effects on soils are shown in Table 7.1 (McConnell et al., 1993). The organic matter added in the compost adds to soil organic carbon (SOC). Briefly, SOC acts as a binding agent in the formation of soil aggregates, and soil aggregate stability is important in maintaining soil structure (Bronick and Lal, 2005). Soil structure is the arrangement of parts within soil, the formation of soil granules and the pore space between them. The quantity, density and integrity of porous spaces between soils impact the soils’ ability to support plant growth, as porosity improves air, water and root travel through the soil.
Erodibility of Two Soft Limestone Road Bases under Tropical Rain
Published in Mark Anglin Harris, Confronting Global Climate Change, 2019
Hydrophobic surfaces reduce wetting rates. Soil hydrophobicity is known to enhance runoff responses to rainstorms and to increase soil aggregate stability, and the increased stability of hydrophobic soil aggregates against slaking may counter an otherwise enhanced susceptibility to erosion (Mataix-Soleraa and Doerr 2004). It is conceivable, therefore, that on hot days, increased gas pressure from melting asphalt tar could have forced molecules down into the porous road bed beneath, thereby producing hydrophobicity on inorganic surfaces. However, the physicochemistry of components in the road bed determines absorption of specific hydrocarbon molecules. Results in the present study show that rapid wetting rates dominated the SLS. Further, whereas the TRL road bed contained 15% kaolinite and 10% hematite, such minerals remained largely absent in the SLS.
Feasibility assessment of bentonite drilling mud to improve the physical quality of loamy sand soil and water deficit of forest plant seedlings
Published in Journal of the Air & Waste Management Association, 2021
Saowanuch Tawornpruek, Surachet Aramrak, Daojarus Ketrot, Chalermchart Wongleecharoen, Worachart Wisawapipat, Natthapol Chittamart, Kittiphong Songrukkiat, Suradanai Augsorntung
Soil physical quality is essential for sustainable agriculture and environmental protection. Vizitiu et al. (2011) defined the two main structural features: (1) the soil must stable in water, and (2) the soil must have a suitable pore size distribution that will enhance the soil balance of air and water for plant use. Soil aggregate stability (SAS) is defined as the soil’s ability to stabilize the structure against disruptive forces derived from either natural or artificial sources (Amézketa, 1999). SAS influences the soil pore geometry and continuity, thereby controlling the fate and transport of mass and energy in a soil system (Herrick et al. 2001). Consequently, it is commonly used as an index determining soil structure and erosion risk (Moncada et al. 2013). S-index is a single indicator of soil microstructural porosity, which is the slope of the soil water retention curve (SWRC) at its inflection point (Dexter 2004a). It can be used in determining the soil physical quality for different soil horizons, soil types, and spatial variations (Fenton et al. 2017). The balance between the water holding capacity and aeration is also a good indicator of soil physical quality and is known as the water storage capacity. This indicator is defined as the soil moisture at field capacity divided by the soil porosity (FC/Pt), and it achieves the optimal balance when FC/Pt is about 0.66 (Reynolds et al. 2002).
Process-based soil erodibility estimation for empirical water erosion models
Published in Journal of Hydraulic Research, 2018
Selen Deviren Saygin, Chi Hua Huang, Dennis C. Flanagan, Gunay Erpul
When the recently measured WEPP-Ki values (Table 3) were compared with those of the historical data (Table 1) of either soil, although comparison was feasible only for the air-dried condition since the latter had no data on saturated and drainage conditions, the Palouse soil Ki was 3.30 times higher while the Nansene soil had similar interrill erodibilities. This indicates that the effect of time passing on the change in WEPP-Ki values might be noticeable. In general, soil organic matter is a feature that can show quite a change according to time and circumstances. Many authors state that soil organic matter increases soil aggregate stability by decreasing wettability and positively improving the cohesion of soil aggregates, and soil cohesion development promotes soil aggregate stability (Amézketa, 1999; Blake & Gilman, 1970; Chenu & Guérif, 1991; Chenu, Le Bissonnais, & Arrouays, 2000; Dalal & Bridge, 1996; Kemper & Rosenau, 1986; Oades, 1993; Tisdall & Oades, 1982). SOC’s effect on physical behaviour of soils was clearly represented in the results here. As expected, the Palouse soil appeared to be more cohesive and have a more stable structure than the Nansene.
Impact of greywater on germination and physiological responses of Triticum aestivum L. HD 2967 in soil amended with poultry biochar
Published in Environmental Technology, 2023
Rekha Kumari, Rozi Sharma, Neeraj Kumar Sharma, Deepak Pant, Piyush Malaviya
Increased global pressure on natural resources, food safety for greater output and profitability, and adjustment and mitigation of climate change are interrelated problems that affect agriculture. Major improvements in agro-ecosystems are required to enhance poor rural economies and create more sustainable agricultural systems by managing agro-residues. Due to the high content of nitrogen and phosphorous in agro-waste, it could be used as a fertilizer (soil conditioner) and to stabilize the soil [1]. As prolonged cultivation causes loss of soil organic matter which ends in declining soil fertility. As a result, soil aggregate stability declines. Therefore, it is essential to restore degraded soils using low-tech, environment-friendly techniques.