Profile cone penetrometer data used to distinguish between soil materials

Comparison of soil depths between evergreen and deciduous forests as a determinant of their distribution, Northeast Thailand

“…Figure 8 shows the annual distribution of precipitation and evapotranspiration of the DEF in the Sakaerat Environmental Research Station. The precipitation data is the average for 1991-2007, and the evapotranspiration is the average for 2001(Gamo 2005. The water supply deficit in the dry season was calculated by summing the monthly water deficits (differences between average evapotranspiration for 2001-2004 and the precipitation) for the period during which the evapotranspiration exceeded the precipitation.…”

“…The soil hardness was expressed as Nc value, the count of weightdropping from 50 cm height for 10 cm penetration of the apparatus into soil. In general, a coarse-textured soil or a soil with a high density has a larger Nc value (Grunwald et al 2001). The Nc value is inversely related to soil water content (Ayers and Perumpral 1982), and decreases close to zero when soil is nearly saturated with water (Faure and Viana Da Mata 1994).…”

Experimental Consideration, Treatments, and Methods in Determining Soil Organic Carbon Sequestration Rates

“…Therefore, soil differences can be reflected in plant performance, productivity, and biomass production as main contributors to SOC input in the soil system. It is helpful to document and demonstrate spatial variability utilizing tools such as threedimensional (3-D) map of the soil to understand the interaction effects of land management practices and soil type on SOC distribution (Grunwald et al 2001a(Grunwald et al , 2001b(Grunwald et al , 2001cArriaga and Lowery, 2005). The use of a soil sampling grid that accounts for surface variability, but also accounts for below soil surface variability within the root zone will provide more accurate accounting for SOC stocks changes or retention.…”

Soil depth and soil water regime in a catchment where tropical dry evergreen and deciduous forests coexist

“…The soil hardness was expressed as the N c value, which is the number of times the weight had to be dropped from 50-cm height for 10-cm penetration of the rod into the soil. In general, a coarse-textured soil or a soil with a high density has a larger N c value (Grunwald et al 2001). In this research, we defined soil depth as the thickness of soil whose N c value was lower than 50 (Onda 1992;Murata et al 2009).…”