Spatial Distribution of Surface Soil Moisture in a Small Forested Catchment

Shoji Noguchi^1*, Yoshio Tsuboyama¹, Roy C. Sidle^2,,3, Tayoko Kubota⁴

¹Forestry and Forest Products Research Institute, Tsukuba, Japan.
²Ecosystems Research Division, US Environmental Protection Agency, Athens, USA.
⁴Tohoku Research Center, Forestry and Forest Products Research Institute, Iwate, Japan.

DOI: 10.4236/jwarp.2014.613111                

Abstract

Predicting the spatial distribution of soil moisture is an important hydrological question. We measured the spatial distribution of surface soil moisture (upper 6 cm) using an Amplitude Domain Reflectometry sensor at the plot scale (2 × 2 m) and small catchment scale (0.84 ha) in a temperate forest. The spatial variation of soil water content was higher during dry conditions than that during wet conditions. Results indicated 3.1 samples at the plot scale were sufficient to estimate mean soil water content when the precision was 0.1. Soil water content increased with increasing topographic index (TI) and soil-topographic index (STI) at the small catchment scale. The correlation between soil water content and TI was higher than that between soil water content and STI. This suggests that topography is more important for estimating surface soil moisture than soil depth as formation of surface soil moisture occurs at ≤6 cm.

Keywords

ADR Sensor, Soil Water Content, Spatial Heterogeneity, Temperate Forest, Topographic Index

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	Wilson, D.J., Western, A.W. and Grayson, R.B. (2004) Identifying and Quantifying Sources of Variability in Temporal and Spatial Soil Moisture Observations. Water Resources Research, 40, W02507.0-W02507.10. http://dx.doi.org/10.1029/2003WR002306
[2]	Beven, K.J. and Kirkby, M.J. (1979) A Physically Based Variable Contributing Area Model of Catchment Hydrology. Hydrological Sciences Bulletin, 6, 279-298.
[3]	Quinn, P.F. and Beven, K.J. (1993) Spatial and Temporal Predictions of Soil Moisture Dynamics, Runoff, Variatble Source Areas and Evapotranspiration for Plynlimon, Mid-Wales. Hydrological Processes, 7, 425-448. http://dx.doi.org/10.1002/hyp.3360070407
[4]	Quinn, P.F., Beven, K.J. and Chevallier, P. (1991) The Prediction of Hillslope Flow Paths for Distributed Hydrological Modeling Using Digital Terrain Models. Hydrological Processes, 5, 59-79. http://dx.doi.org/10.1002/hyp.3360050106
[5]	Lamb, R., Beven, K.J. and Myrabø, S. (1997) Discharge and Water Table Predictions Using a Generalized Topmodel Formulation. Hydrological Processes, 11, 1145-1167. http://dx.doi.org/10.1002/(SICI)1099-1085(199707)11:9<1145::AID-HYP550>3.0.CO;2-C
[6]	Noguchi, S., Tsuboyama, Y., Sidle, R.C. and Hosoda, I. (1999) Morphological Characteristics of Macropores and the Distribution of Preferential Flow Pathways in a Forested Slope Segment. Soil Science Society of America Journal, 63, 1413-1423. http://dx.doi.org/10.2136/sssaj1999.6351413x
[7]	Mosley, M.P. (1982) Subsurface Flow Velocities through Selected Forest Soils, South Island, New Zealand. Journal of Hydrology, 55, 65-92. http://dx.doi.org/10.1016/0022-1694(82)90121-4
[8]	Tsuboyama, Y. (2006) An Experimental Study on Temporal and Spatial Variability of Flow Pathways in a Small Forested Catchment. Bulletin of FFPRI, 399, 135-174.
[9]	Quinn, P.F., Beven, K.J. and Lamb, R. (1995) The ln(a/tanb) Index: How to Calculate and How to Use It within the Topmodel Framework. Hydrological Processes, 9, 161-182. http://dx.doi.org/10.1002/hyp.3360090204
[10]	Sunada, K., Itoh, T. and Miyano, Y. (1995) Characteristics of Spatial Distribution of Surface Soil Moisture in Bare Fields (in Japanese with English Summary). Journal Of Japan Society Of Hydrology And Water Resources, 8, 210-216. http://dx.doi.org/10.3178/jjshwr.8.210
[11]	Moroizumi, T., Sata, Y. and Sato, K. (2002) Spatial Variability of Surface Soil Moisture and Investigation of the Local Sampling Sites Exhibiting Field Average in a Slope Grassland Field. Transactions of the Japanese Society of Irrigation, Drainage and Rural Engineering, 220, 447-455. (In Japanese)
[12]	Tsuboyama, Y., Sidle, R.C., Noguchi, S. and Hosoda, I. (1994) Flow and Solute Transport through the Soil Matrix and Macropores of a Hillslope Segment. Water Resources Research, 30, 879-890. http://dx.doi.org/10.1029/93WR03245
[13]	Sidle, R.C., Tsuboyama, Y., Noguchi, S., Hosoda, I., Fujieda, M. and Shimizu, T. (2000) Stormflow Generation in Steep Forested Headwaters: A Linked Hydrogeomorphic Paradigm. Hydrological Processes, 14, 369-385. http://dx.doi.org/10.1002/(SICI)1099-1085(20000228)14:3<369::AID-HYP943>3.0.CO;2-P
[14]	Noguchi, S., Tsuboyama, Y., Sidle, R.C. and Hosoda, I. (2001) Subsurface Runoff Characteristics from a Forest Hillslope Soil Profile Including Macropores, Hitachi Ohta, Japan. Hydrological Processes, 15, 2131-2149. http://dx.doi.org/10.1002/hyp.278
[15]	Miyata, S., Kosugi, K., Nishi, Y., Gomi, T., Sidle, R.C. and Mizuyama, T. (2010) Spatial Pattern of Infiltration Rate and Its Effect on Hydrological Processes in a Small Headwater Catchment. Hydrological Processes, 24, 535-549. http://dx.doi.org/10.1002/hyp.7549
[16]	Kobayashi, M., Tsurita, T., Itoh, Y. and Kato, M. (2006) Spatial Distribution of Soil Water Repellency in a Japanese Cypress Plantation and an Adjacent Deciduous Broad-Leaved Forest. Journal of the Japanese Forest Society, 88, 354-362. http://dx.doi.org/10.4005/jjfs.88.354
[17]	Gottlein, A. and Manderscheid, B. (1998) Spatial Heterogeneity and Temporal Dynamics of Soil Water Tension in a Mature Norway Spruce Stand. Hydrological Processes, 12, 417-428. http://dx.doi.org/10.1002/(SICI)1099-1085(19980315)12:3<417::AID-HYP583>3.0.CO;2-B
[18]	Noguchi, S., Tsuboyama, Y., Sidle, R.C. and Hosoda, I. (1997) Spatially Distributed Morphological Characteristics of Macropores in Forest Soils of Hitachi Ohta Experimental Watershed, Japan. Journal of Forest Research, 2, 207-215. http://dx.doi.org/10.1007/BF02348317
[19]	Ohta, T. (1988) Storm Runoff Mechanism on Forested Slopes. Journal of Japan Society of Hydrology and Water Resources, 1, 75-82. (In Japanese) http://dx.doi.org/10.3178/jjshwr.1.75
[20]	Sidle, R.C., Hirano, T., Gomi, T. and Terajima, T. (2007) Hortonian Overland Flow from Japanese Forest Plantations—An Aberration, the Real Thing, or Something in between? Hydrological Processes, 21, 3237-3247. http://dx.doi.org/10.1002/hyp.6876
[21]	Taniguchi, M., Tsujimura, M. and Tanaka, T. (1996) Significance of Stremflow in Groundwater Recharge. 1: Evaluation of the Stemflow Contribution to Recharge Using a Mass Balance Approach. Hydrological Processes, 10, 71-80. http://dx.doi.org/10.1002/(SICI)1099-1085(199601)10:1<71::AID-HYP301>3.0.CO;2-Q
[22]	Tsuboyama, Y., Hosoda, I. and Noguchi, S. (1990) Heat and Water Transfer in Surface Soil Layer of Forest (II) Horizontal Distribution of Soil Moisture Near a Tree. Transactions of the 101th Annual Meeting of the Japanese Forest Society, Kyoto, 2-4 April 1990, 597-600. (In Japanese)
[23]	Konishi, M., Tani, M., Kosugi, Y., Takanashi, S., Sahat, M.M., Nik, A.R., Niiyama, K. and Okuda, T. (2006) Characteristics of Spatial Distribution of Throughfall in a Lowland Tropical Rainforest, Peninsular Malaysia. Forest Ecology and Management, 224, 19-25. http://dx.doi.org/10.1016/j.foreco.2005.12.005
[24]	Noguchi, S., Nik, A.R., Baharuddin, K., Tani, M., Sammori, T. and Morisada, K. (1997) Soil Physical Properties and Preferential Flow Pathways in Tropical Rain Forest, Bukit Tarek, Peninsular Malaysia. Journal of Forest Research, 2, 115-120. http://dx.doi.org/10.1007/BF02348479
[25]	Ghestem, M., Sidle, R.C. and Stokes, A. (2011) The Influence of Plant Root Systems on Subsurface Flow: Implications for Slope Stability. BioScience, 61, 869-879. http://dx.doi.org/10.1525/bio.2011.61.11.6