ASA Southern Branch 2007 Annual Meeting
February 4-6, 2007
Mobile, AL
The soil resource is an integral part of sustainability. Management dependent properties describe
dynamic soil quality, however, comparisons of
disturbed to reference sites are not extensive in the SE due to scarcity of
undisturbed land. Objectives of this
study are to evaluate land use and management effects on dynamic soil
properties of southeastern soils and investigate carbon (C) stocks and soil
quality of mature longleaf-wiregrass habitat relative to more intensively
cultivated Coastal Plain ecosystems. Sites in Thomas County, GA, representing
three soil map units (sandy surfaces with loamy to clayey kandic subsurface
horizons) were selected in each of three management systems for comparison of near
surface (0-5, 5-15 and 15-30 cm) soil chemical, physical, and biological
properties. Land management/use included
mature longleaf pine (Pinus palustrus
Miller) – wiregrass (Aristida stricta Michx.)
habitat (LL), slash pine (Pinus elliottii Engelm.) plantation (PP), and conventional row cropping systems
(RC). Microbial biomass C (0-5 cm) was 57
and 101 % higher in LL compared with PP and RC, respectively, while total
organic C was 68 and 148 % higher in LL relative to PP and RC, respectively. Anthropogenic
inputs were evident in RC (0-30 cm) based on high TON (21 and 28 % > LL and
PP), Ca (92 and 186 % > PP and LL), Mg (57 and 50 % > LL and PP), K (180
and 600 % > PP and LL), P (204 and 1600 % > PP and LL), and base
saturation (107 and 148 % > PP and LL).
Bulk density was highest in RC across
all depths with the greatest differences at 0-5 cm (RC 19 % > PP) and 5-15
cm (RC 34 % > LL). More intensive
cultivation increased nutrient levels and soil compaction, and decreased C
stocks of investigated soils relative to uncultivated sites.
See more of Graduate Student Poster Competition--Soils
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