Soil hydraulic properties of cropland compared with reestablished and native grassland

被引:115
作者
Schwartz, RC [1 ]
Evett, SR [1 ]
Unger, PW [1 ]
机构
[1] USDA ARS, Conservat & Prod Res Lab, Bushland, TX 79012 USA
关键词
hydraulic properties; porosity; hydraulic conductivity; soil management; tillage; infiltrometers;
D O I
10.1016/S0016-7061(03)00093-4
中图分类号
S15 [土壤学];
学科分类号
0903 ; 090301 ;
摘要
Conversion of cropland to perennial grasses will, over time, produce changes in soil hydraulic properties. The objective of this study was to characterize and compare hydraulic properties of fine-textured soils on adjacent native grassland, recently tilled cropland, and reestablished grassland in the Conservation Reserve Program (CRP) at three locations in the Southern Great Plains. A tension infiltrometer was used to measure unconfined, unsaturated infiltration over a range of supply pressure heads (nominally, h = -150, -100, -50, and -5 mm H2O) at the soil surface. Intact soil cores were sampled within the Ap and Bt horizons to determine bulk density and water desorption curves, theta(h), at potentials ranging from -0.15 to -100 kPa. Unsaturated hydraulic conductivity K(h) over the range in supply pressure heads was estimated using Wooding's equation for steady-state flow from a disc source. The van Genuchten water retention model was fitted to theta(h) data to estimate parameter values. Soils in CRP had greater surface bulk densities than their grassland and cropland counterparts. The shape of the soil water retention curve for grassland and CRP land were similar, suggesting that converted croplands had fully reconsolidated. Mean near-saturated hydraulic conductivities of cropland at h = -5 mm were not significantly different from grassland. However, at -150 mm supply pressure head, cropped soils had a mean unsaturated conductivity 2.3 and 4.1 times greater than CRP land and grassland, respectively. Sites in CRP had the lowest (P < 0.05) near-saturated hydraulic conductivities (h = -5 mm), which suggest that after 10 years, grasses had not fully ameliorated changes in pore structure caused by tillage. Comparison of unsaturated conductivities for grassland and CRP land suggest that long-term structural development on native grasslands was principally confined to effective pore radii greater than 300 mum. Land use practices had a greater effect on water movement than did soil series, indicating that the modifying effects of tillage, reconsolidation, and pore structure evolution on hydraulic properties are important processes governing water movement in these fine-textured soils. (C) 2003 Elsevier Science B.V. All rights reserved.
引用
收藏
页码:47 / 60
页数:14
相关论文
共 32 条
[1]   Changes in soil water retention curves due to tillage and natural reconsolidation [J].
Ahuja, LR ;
Fiedler, F ;
Dunn, GH ;
Benjamin, JG ;
Garrison, A .
SOIL SCIENCE SOCIETY OF AMERICA JOURNAL, 1998, 62 (05) :1228-1233
[2]   Field measurement of soil surface hydraulic properties by disc and ring infiltrometers - A review and recent developments [J].
Angulo-Jaramillo, R ;
Vandervaere, JP ;
Roulier, S ;
Thony, JL ;
Gaudet, JP ;
Vauclin, M .
SOIL & TILLAGE RESEARCH, 2000, 55 (1-2) :1-29
[3]   Seasonal variation of hydraulic properties of soils measured using a tension disk infiltrometer [J].
AnguloJaramillo, R ;
Moreno, F ;
Clothier, BE ;
Thony, JL ;
Vachaud, G ;
FernandezBoy, E ;
Cayuela, JA .
SOIL SCIENCE SOCIETY OF AMERICA JOURNAL, 1997, 61 (01) :27-32
[4]   SIMPLE FIELD METHOD FOR DETERMINING UNSATURATED HYDRAULIC CONDUCTIVITY [J].
ANKENY, MD ;
AHMED, M ;
KASPAR, TC ;
HORTON, R .
SOIL SCIENCE SOCIETY OF AMERICA JOURNAL, 1991, 55 (02) :467-470
[5]   CHARACTERIZATION OF TILLAGE AND TRAFFIC EFFECTS ON UNCONFINED INFILTRATION MEASUREMENTS [J].
ANKENY, MD ;
KASPAR, TC ;
HORTON, R .
SOIL SCIENCE SOCIETY OF AMERICA JOURNAL, 1990, 54 (03) :837-840
[6]  
[Anonymous], 1991, EPA600291065 RS KERR
[7]   TILLAGE EFFECTS ON NEAR-SURFACE SOIL HYDRAULIC-PROPERTIES [J].
BENJAMIN, JG .
SOIL & TILLAGE RESEARCH, 1993, 26 (04) :277-288
[8]  
Brooks R. H., 1964, Hydrology paper, V3
[9]   PROBABILITY LAWS FOR PORE-SIZE DISTRIBUTIONS [J].
BRUTSAERT, W .
SOIL SCIENCE, 1966, 101 (02) :85-+
[10]  
EVETT SR, 1999, CHARACTERIZATION M 1, P541