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Runoff hydrology
Published in James C.Y. Guo, Wenliang Wang, Junqi Li, Urban Drainage and Storage Practices, 2023
James C.Y. Guo, Wenliang Wang, Junqi Li
Infiltration is the process of transferring surface water into the top layer of soil. A soil layer becomes saturated when its pores are filled up with water. Seepage flows through soil layers may move laterally into streams and lakes or vertically into groundwater aquifers. The infiltration rate varies with respect to the topsoil texture and the water content of the soil. The soil porosity, θs, of the soil column is defined as: θs= void volume/column volume
Dynamic Curve Numbers
Published in Saeid Eslamian, Faezeh Eslamian, Flood Handbook, 2022
Sara Nazif, Pouria Soleimani, Saeid Eslamian
Hydrologic soil groups which are used in the CN method are based on the infiltration rate of undisturbed and normal soils. Construction projects in urban areas have an effect on the soil density and make soil more compacted. Soil compaction influences the infiltration rate of soil and decreases it in comparison with normal soil. Therefore, the runoff rate in reality is more than the estimated amount which means that using original HSGs is inaccurate. Thus it is recommended to consider the effect of soil compaction for runoff estimation especially in urban areas (Lim et al., 2006).
Classification of Soil Water
Published in A. Zaman, Md. Hedayetullah, Sustainable Water Resource Development and Management, 2022
Soil texture: Infiltration rate is more in coarse-textured soils as compared with heavy soils (clay). In coarse-textured soil (sandy soil), the number of macropores are more. The cracking caused in clay soil by drying up with high solar radiation also increases infiltration in the initial stages until the soil again swells up.
Comparing single-wheel attachable tracks to chains and bare tires on skidders for mitigating soil disturbance during harvesting operations
Published in International Journal of Forest Engineering, 2023
Taylor Richmond, Rene H. Germain, Kristopher Brown, Russell Briggs, Stephen Stehman
Soil compaction is a natural phenomenon that results from increased force on the soil which can occur as a result of intense rainfall, growth of plant roots, and foot traffic from animals (Taylor and Brar 1991). However, the most impactful force in forests is usually associated with the machinery used to harvest timber (Greacen and Sands 1980). Soil compaction has adverse effects on root growth, water infiltration, and soil aeration. Compression of the soil destroys macropores, which reduces total porosity, resulting in less gaseous exchange within the soil profile. This reduces soil infiltration capacity, leading to increased and concentrated surface runoff which makes its way to water bodies, leading to sedimentation. Soil compaction also restricts root growth and uptake of water and nutrients, reducing tree growth (Greacen and Sands 1980; Naghdi et al. 2018; Zemánek and Neruda 2021). Roots must penetrate nearby soil to elongate and grow. With increased compaction and decreased macroporosity, root growth is both slowed and truncated (Greacen and Sands 1980; Taylor and Brar 1991). Soil compaction can be measured via bulk density and mechanical resistance. Soil bulk density is defined as the mass of the soil per unit volume of soil, whereas mechanical resistance is the reaction of the soil to the forces exerted by growing plants. Both measures serve to indicate ease of root penetration through the soil, predict water transmission, and indicate soil quality (Grossman and Reinsch 2002).
When the virtual water runs out: local and global responses to addressing unsustainable groundwater consumption
Published in Water International, 2022
Iman Haqiqi, Chris J. Perry, Thomas W. Hertel
In sum, there are four stages of groundwater development: (1) the natural state of precipitation, vegetation and runoff; (2) progressive human interventions that expand use (agriculture, domestic water supply, etc.) at the expense of other outflows, while maintaining equilibrium between inflows and outflows; (3) groundwater mining, where outflows exceed inflows, and the aquifer is progressively depleted; and (4) effective depletion of the aquifer, often associated with: (a) subsidence of the land surface, which in many areas is already ongoing and substantial (Galloway & Burbey, 2011); (b) compaction of the soil, so that infiltration is restricted and storage of soil moisture in the profile is reduced; and (c) extended time for any infiltration to reach the saturated zone, due to a combination of (b), above, and the ever-increasing depth to the water table. Unfortunately, many aquifers around the world are at the third stage listed above, and in the absence of interventions by the relevant authorities, they will automatically progress to the fourth stage of irreparable damage.
The feasibility of reusing highway runoff for fabric dyeing: a proof of concept
Published in Journal of Applied Water Engineering and Research, 2022
Muhammad Arslan, Irfan Ahmed Shaikh
The complex process of converting land uses from rural to urban involving increased population and economic activities by developing more land for roads, bridges, subways, water facilities/ utilities, housing and industrial uses is called urbanization (Al-Mashaqbeh et al. 2014). Urbanization adversely impacts infiltration by increasing impervious surfaces. Rainfall/ stormwater that would have previously infiltered now is stormwater run-off due to a reduction in total pervious area (Fernando and Rathnayake 2018; Hamaamin 2018). Amplified flood peaks and run-off volumes are typical results of urbanization, while other hydrologic consequences of urbanization include decreased baseflow, increased loads of nutrients, sediment, and heavy metals. An urbanized landscape has many hallmarks, but the presence of many impervious areas in the form of roads and parking lots is probably the most pervasive, relevant characteristic leading to hydrologic impacts (Moglen 2009). The increased impervious area caused a severe reduction of water percolation down to the ground and enhanced run-off volume during the rain events (Chow and Yusop 2009; Kamali et al. 2012; Al-Mashaqbeh et al. 2014; Toor et al. 2017).