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Turfgrasses benefit the environment through conversion of CO2 into stable C stored in soils. Limited research on the sequestration potential of bermudagrass (Cynodon spp.) has been conducted in semiarid climates. The objective of this study was to evaluate soil physiochemical properties of golf courses in Lubbock, TX, to determine C sequestration potential and longevity. Soil was obtained from fairways of five golf courses ranging in age from 13 to 93 yr. Shallow (0–7.5 cm) and deeper (7.5–15 cm) soil depths were tested for soil pH, electrical conductivity, soil organic matter, soil organic C (SOC), inorganic C, total N, inorganic N, and texture. After ANOVA and mean separation, principal component analysis (PCA) was used to group golf courses by soil depth or age. Soil organic matter and SOC decreased with depth, but the rate of SOC accumulation (0.22 Mg C ha−1 yr−1) was lower when compared with previous studies. Maximal C (35.1 and 23.7 Mg C ha−1 in the upper and lower depths) was consistent with previous studies, indicating that C accumulated for a longer period of time. The PCA explained 52.7% of variability in soil physiochemical properties on two axes, but PCA more effectively differentiated soil sampling depth than golf course age. High variability in data among fairways at a single golf course likely resulted in limited grouping capabilities. Including a broader regional representation of golf courses or sampling golf courses between 40 and 70 yr to quantify soils near maximal accumulation would strengthen future studies. [ABSTRACT FROM AUTHOR]

Soil organic matter (SOM) accumulation and carbon (C) sequestration are ecosystem services (ESs) provided by urban landscapes that are dominated by continuous grass cover, such as residential lawns. Organic matter and C sequestration are expected to increase over time, but few studies have determined potential soil organic carbon (SOC) accumulation from residential lawns in semiarid climates. The objectives were to evaluate physiochemical attributes of urban soils established under turfgrass landscapes of different ages and determine soil factors that differentiate urban soils in semiarid climate of Lubbock, TX. Soil samples (0−10 cm) were obtained from 10 residential lawns of homes built: pre-1970 (oldest), 1971−1990 (middle), 1991−2010 (newer), and after 2011 (newest). Soil texture, bulk density, extractable nutrients [phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), and iron (Fe)], pH, SOM, SOC, and total nitrogen (TN) were determined. Bulk density and pH were highest in newest homes and lowest in oldest homes. Increasing years of lawn establishment increased SOM, SOC, and TN content. Linear regression determined 0.036 % annual increase in SOM for residential lawns, but SOC accumulated at 0.021 kg C m−2 yr-1 for 53.6 yr. In principal component (PC) analysis, SOM, SOC, and TN contributed most to PC1 (36.2 %) reflecting components separating residential lawns by years of establishment, and primarily soil texture components for PC2 (22.5 %). The results of this study show that home age is a strong determinant of soil carbon content in semiarid urban turfgrass systems, with the greatest accumulation threshold in oldest homes over 50 years of age. [ABSTRACT FROM AUTHOR]