Soil organic carbon storage in mountain grasslands of the Pyrenees: effects of climate and topography

摘要: The prediction of soil C stocks across the landscape has been increasingly studied in many areas world. Soil organic storage mountain is highly heterogeneous, mainly as a result local-scale variability environment (topography, stoniness, parent material) and microclimate. aims present study are to estimate (SOCS) mineral soils high-altitude grasslands Pyrenees determine whether climatic topographic variables can be used predictors SOCS content surface horizons these ecosystems. For that purpose we sampled 35 profiles subalpine alpine including range altitudes, slopes aspects. We analysed for bulk density, total C, texture, C-to-N ratio determined topographical variables. georeferenced information descriptions sites. were correlated with depth. However, not able predict depth by using environmental In spite this fact, altitude aspect explained 41.2% while summer temperature precipitation combined 56.9% layer (OC). low at high probably an overall limitation net primary productivity. Under conditions, effect was small. highest occurred lowest altitudes ENE or WNW aspects, showing sharper decreases towards south than north. harsh conditions low-plant productivity occur northern reduced altitudes. contrast, southern aspects showed similar along altitudinal gradient. OC partially related characteristics matter, which may depend on plant communities.