Landscape position influences soil respiration variability and sensitivity to physiological drivers in mixed‐use lands of Southern California, USA

Abstract

Linking variation in ecosystem functioning to physiological and landscape drivers has become an important research need for understanding ecosystem responses to global changes. We investigate how these contrasting scale‐dependent ecosystem drivers influence soil respiration (Rs), a key ecosystem process, using in situ landscape surveys and experimental subsidies of water and labile carbon. Surveys and experiments were conducted in summer and winter seasons and were distributed along a coastal to desert climate gradient and among the dominant land use classes in Southern California, USA. We found that Rs decreased from lawn to agricultural and wildland land uses for both seasons and along the climate gradient in the summer while increasing along the climate gradient in the winter. Rs variation was positively correlated with soil temperature and negatively to soil moisture and substrate. Water additions increased Rs in wildland land uses, while urban land uses responded little or negatively. However, most land uses exhibited carbon limitation, with wildlands experiencing largest responses to labile carbon additions. These findings show that intensively managed land uses have increased rates, decreased spatial variation, and decreased sensitivity to environmental conditions in Rs compared to wildlands, while increasing aridity has the opposite effect. In linking scales, physiological drivers were correlated with Rs but landscape position influenced Rs by altering both the physiological drivers and the sensitivity to the drivers. Systematic evaluation of physiological and landscape variation provides a framework for understanding the effects of interactive global change drivers to ecosystem metabolism across multiple scales.

Diverging patterns at the forest edge: Soil respiration dynamics of fragmented forests in urban and rural areas

“…Urban soils are subject to biogeochemical perturbations distinct from their fragmented rural forest counterparts and experience a variety of disturbances, including intensive, and extensive management with implications for local carbon budgets (Decina et al, 2016; Hundertmark et al, 2021; Vasenev et al, 2018). Intensively managed, non‐forested urban soils demonstrate substantial increases in respiration compared to soils in nearby “natural” systems due in part to increased applications of compost and mulch (Crum et al, 2016; Decina et al, 2016; Vasenev et al, 2018). However, soil respiration patterns at urban forest edges have yet to be characterized.…”

Uncovering the ecosystem service legacies of wetland loss using high‐resolution models

“…For example, landscape position affects the types of land cover changes occurring and also effects the process rates of many ecosystem functions (Crum et al. ). In particular, wetland processes vary greatly depending on their landscape position and context (Mitsch and Gosselink , Cohen et al.…”

“…Here, despite exploring the impacts of initial and present land cover condition on ecosystem services, a great deal of spatial heterogeneity remains unexplained, and greater exploration of landscape position and its effect on ecosystem service outcomes is warranted. For example, landscape position affects the types of land cover changes occurring and also effects the process rates of many ecosystem functions (Crum et al 2016). In particular, wetland processes vary greatly depending on their landscape position and context Gosselink 2000, Cohen et al 2016).…”

Influence of Climate and Management on Patterns of Taxonomic and Functional Diversity of Recreational Park Vegetation

“…Fertilization, pesticide application, prioritizing play equipment, and access to local nurseries can all lead to variations in taxonomic and functional vegetation diversity (Kjelgren and Clark, 1993;Politi Bertoncini et al, 2012;Chan et al, 2014;Cavender-Bares et al, 2020). Urban soil profiles can be both heterogeneous within and among cities (Crum et al, 2016;Herrmann et al, 2018). Regional climate and human facilitation are major filters leading to taxonomic and functional diversity (Aronson et al, 2016;Pearse et al, 2018), however, future work would be inclined to explore other potential narrower urban filters on recreational park diversity.…”