COS 59-3 - Impacts of land-use intensification on soil-based ecosystem services in an agricultural landscape in the Peruvian Andes

Tuesday, August 8, 2017: 2:10 PM
B112, Oregon Convention Center
Steven Fonte1, Steven Vanek1, Katherin Meza2, Anne de Valenca3, Raul Ccanto2, Edgar Olivera2 and Maria Scurrah2, (1)Soil and Crop Sciences, Colorado State University, Fort Collins, CO, (2)Grupo Yanapai, Huancayo, Peru, (3)Wageningen University, Netherlands
Background/Question/Methods:

Mountainous landscapes throughout the Andean highlands have been under cultivation for millennia, but growing food demand, agricultural modernization, and climate change have intensified land-use patterns, with concerning implications for ecosystem services (ES) and biodiversity. Based on these challenges we sought to understand the impact of current and future land-use practices on a suite of soil-based ES in an agricultural landscape of central Peru, so as to inform landscape planning and sustainable management decisions. We worked with the community of Quilcas, Junin Dept, Peru to identify and map ten dominant land-uses in their community (total area of 7,900 ha). In a low-mid elevation zone (3200-3800m) land-use was dominated by three cropping systems (rain-fed cropping with grazed fallows, rain-fed continuous cropping, and irrigated crops), three forest types (eucalyptus, alder and mixed/native species), permanent pasture, and degraded lands. In a high elevation zone (3800-4300m) there were two dominant land-uses: dryland cropping with extended, grazed fallows and permanent pasture. Sampling points stratified across these land-uses were evaluated using composite indicators of multiple soil and vegetation variables for the following ES: soil fertility and nutrient provision, erosion control, C storage, biodiversity conservation of ground vegetation and soil macrofauna, and economic production potential.

Results/Conclusions:

Overall, land-uses differed substantially in the ES provided. For example, in the low-middle elevation zone (where most agricultural activity occurs), forests (especially alder and mixed forest) supported the highest C storage, soil fertility and macrofauna abundance and diversity. The high elevation land-uses also supported high levels of soil fertility and C storage, and permanent pasture in this zone demonstrated the highest vegetative diversity. Erosion control (assessed via infiltration, soil cover and bulk density) was lowest in the degraded lands and highest in mid-elevation forests and high elevation pasture. Net economic productivity was high in the low-mid elevation cropping systems and the eucalyptus forest. Irrigated crop areas that were frequently rotated to perennial forages were particularly lucrative with minimal sacrifice to ES, and high-elevation potatoes in rotation with grazed fallows also performed well due to low input and ES provided during fallow. While economic productivity was low, alder forests supported a range of ES and may offer an important means to restore degraded lands. Our landscape assessment identified important tradeoffs and synergies in ES from different land-uses that can support future community landscape planning and conservation efforts in Quilcas and similar smallholder based communities in the region.