The effect of tillage on soil surface properties and the water balance of a xeralfic alfisol

1984 ◽  
Vol 4 (6) ◽  
pp. 543-559 ◽  
Author(s):  
A.P. Hamblin
Keyword(s):  
Water Balance ◽  
Surface Properties ◽  
Soil Surface

scholarly journals Impacts of ditch cleaning on hydrological processes in a drained peatland forest

2008 ◽  
Vol 5 (1) ◽  
pp. 147-182 ◽  
Author(s):  
H. Koivusalo ◽  
E. Ahti ◽  
A. Laurén ◽  
T. Kokkonen ◽  
T. Karvonen ◽  
...  
Keyword(s):  
Water Balance ◽  
Water Movement ◽  
Soil Surface ◽  
Snow Accumulation ◽  
Forest Growth ◽  
Understorey Vegetation ◽  
Growing Stock ◽  
Network Maintenance ◽  
Stock Volume ◽  
Ditch Cleaning

Abstract. One fourth (5.5 Mha) of forests in Finland are growing on peatlands that have been drained to improve forest growth. Forestry operations such as cuttings and ditch network maintenance in these areas may increase export of suspended solids and nutrients, and deteriorate water quality in receiving lakes and rivers. Mitigation of the deterioration calls for understanding how forest management operations affect peatland hydrology. A process-based simulation model FEMMA was applied to quantify the effects of ditch network maintenance on peatland water balance. The model has separate computation routines for evapotranspiration in tree stand and understorey vegetation, snow accumulation and melt, water movement in unsaturated and saturated soil, and drainage. Hydraulic characteristics of peat, as well as different drainage designs can be parameterised in the model. The model was applied in artificially delineated research catchments in northern Finland, where the ditch network was maintained by cleaning and digging the ditches deeper. The simulation results indicated that ditch cleaning affected the water balance slightly and the effect was dependent on stand characteristics and soil structure. When the growing stock volume was low and poorly conductive soil extended close to the soil surface, ditch cleaning increased evapotranspiration. In stands with a high stock volume and a thick topmost layer of highly conductive soil, evapotranspiration was less affected. In the study catchments, the effect of ditch cleaning on runoff was small compared to the error between measured and modelled runoff.

scholarly journals Ecohydrologic controls on vegetation density and evapotranspiration partitioning across the climatic gradients of the central United States

2008 ◽  
Vol 5 (2) ◽  
pp. 649-700 ◽  
Author(s):  
J. P. Kochendorfer ◽  
J. A. Ramírez
Keyword(s):  
United States ◽  
Soil Moisture ◽  
Water Balance ◽  
Soil Water ◽  
Water Use ◽  
Soil Surface ◽  
Soil Water Balance ◽  
Vegetation Density ◽  
Study Region ◽  
Central United States

Abstract. The soil-water balance and plant water use are investigated over a domain encompassing the central United States using the Statistical-Dynamical Ecohydrology Model (SDEM). The seasonality in the model and its use of the two-component Shuttleworth-Wallace canopy model allow for application of an ecological optimality hypothesis in which vegetation density, in the form of peak green leaf area index (LAI), is maximized, within upper and lower bounds, such that, in a typical season, soil moisture in the latter half of the growing season just reaches the point at which water stress is experienced. Another key feature of the SDEM is that it partitions evapotranspiration into transpiration, evaporation from canopy interception, and evaporation from the soil surface. That partitioning is significant for the soil-water balance because the dynamics of the three processes are very different. The partitioning and the model-determined peak in green LAI are validated based on observations in the literature, as well as through the calculation of water-use efficiencies with modeled transpiration and large-scale estimates of grassland productivity. Modeled-determined LAI are seen to be at least as accurate as the unaltered satellite-based observations on which they are based. Surprising little dependence on climate and vegetation type is found for the percentage of total evapotranspiration that is soil evaporation, with most of the variation across the study region attributable to soil texture and the resultant differences in vegetation density. While empirical evidence suggests that soil evaporation in the forested regions of the most humid part of the study region is somewhat overestimated, model results are in excellent agreement with observations from croplands and grasslands. The implication of model results for water-limited vegetation is that the higher (lower) soil moisture content in wetter (drier) climates is more-or-less completely offset by the greater (lesser) amount of energy available at the soil surface. This contrasts with other modeling studies which show a strong dependence of evapotranspiration partitioning on climate.

scholarly journals GEOPHYSICAL SURVEY AS A TOOL TO REVEAL SUBSURFACE STRATIFICATION AT A SMALL AGRICULTURAL HEADWATER CATCHMENT: A CASE STUDY

2021 ◽  
Vol 30 (3) ◽  
Author(s):  
Jakub Jeřábek ◽  
David Zumr
Keyword(s):  
Water Balance ◽  
Surface Topography ◽  
Soil Profile ◽  
Land Surface ◽  
Soil Surface ◽  
Geophysical Survey ◽  
Drainage Area ◽  
Survey Method ◽  
Deep Drainage ◽  
Headwater Catchment

Catchment drainage area is a basic spatial unit in landscape hydrology within which the authorities estimate a water balance and manage water resources. The catchment drainage area is commonly delineated based on the surface topography, which is determined using a digital elevation model. Therefore, only a flow over the surface is implicitly considered. However, a substantial portion of the rainfall water infiltrates and percolates through the soil profile to the groundwater, where geological structures control the drainage area instead of the topography of the soil surface. The discrepancy between the surface topography-based and bedrock-based drainage area can cause large discrepancies in water balance calculation. It this paper we present an investigation of the subsurface media stratification in a headwater catchment in the central part of the Czech Republic using a geophysical survey method - electrical resistivity tomography (ERT). Results indicate that the complexity of the subsurface geological layers cannot be estimated solely from the land surface topography. Although shallow layers copy the shape of the surface, the deeper layers do not. This finding has a strong implication on the water transport regime since it suggests that the deep drainage may follow different pathways and flow in other directions then the water in shallow soil profile or shallow subsurface structures.

Soil Erodibility as Affected by Soil Surface Properties

1971 ◽  
Vol 14 (4) ◽  
pp. 0647-0648 ◽  
Author(s):  
E. Epstein and W. J. Grant
Keyword(s):  
Surface Properties ◽  
Soil Surface ◽  
Soil Erodibility

scholarly journals Test of a microlysimeter for measurement of soil evaporation

2012 ◽  
Vol 32 (1) ◽  
pp. 80-90 ◽  
Author(s):  
Danilton L. Flumignan ◽  
Rogério T. de Faria ◽  
Bruno P. Lena
Keyword(s):  
Water Balance ◽  
Water Use Efficiency ◽  
Soil Water ◽  
Water Use ◽  
Soil Surface ◽  
Bare Soil ◽  
Soil Evaporation ◽  
Soil Water Balance ◽  
Use Efficiency ◽  
Inner Diameter

Quantifying soil evaporation is required on studies of soil water balance and applications aiming to improve water use efficiency by crops. The performance of a microlysimeter (ML) to measure soil evaporation under irrigation and non-irrigation was evaluated. The MLs were constructed using PVC tubes, with dimensions of 100 mm inner diameter, 150 mm depth and 2.5 mm wall thickness. Four MLs were uniformly distributed on the soil surface of two weighing lysimeters conducted under bare soil, previously installed at Iapar, in Londrina, PR, Brazil. The lysimeters had 1.4 m width, 1.9 m length and 1.3 m depth and were conducted with and without irrigation. Evaporation measurements by MLs (E ML) were compared with measurements by lysimeters (E L) during four different periods in the year. Differences between E ML and E L were small either for low or high atmospheric demand and also for either irrigated or non-irrigated conditions, which indicates that the ML tested here is suitable for measurement of soil evaporation.

Sign in / Sign up

Export Citation Format

Share Document