Agricultural landscapes play an important role in global carbon (C) emissions. Rehabilitation of agricultural riparian buffers with trees (agroforestry) provides a unique and elegant solution to enhance ecosystem services, such as reducing agricultural emissions and augmenting local biodiversity. Using riparian agroforestry buffers which were i) young (Y); 15 years since planting and ii) mature (M); >25 years since planting, our study investigated plant functional trait diversity in riparian species and assessed rates of soil CO2 efflux (mg/m2/h) and nitrogen (N) mineralization (mg·kg−1). We use piecewise structural equation modelling to assess the role of abiotic (climate and soil) and biotic (above and below-ground plant functional traits and microbial abundance) indices on soil C and N cycling processes within managed riparian agroforestry systems.
Results/Conclusions
We found significantly lower rates of CO2 efflux in mature buffers (196.21 ± 31.75) as compared with young buffers (425.60 ± 32.95) over one growing season. Using our model, we show significantly different pathways that explain the key drivers of soil functioning between young and mature riparian buffers. Clearly, key plant-soil dynamics change over the lifespan of a newly planted and mature riparian agroforestry buffer with consequences for ecosystem services.