Location
The PUKERS, as one of the only two monitoring and research stations of karst ecosystems of CERN, generally aims to provide long-term, permanent monitoring and investigation of karst ecosystems in 3D and comprehensive approaches. A technical standard of ecosystem monitoring for karst landscape will then be established. The structure, functions, patterns, and processes of karst ecosystems on the Guizhou Plateau will be revealed by long-term monitoring and control experiments of the material cycles and energy flows at different spatial and temple scales and under various perturbations by human activities. The mechanism of self-maintenance and its key driving forces of karst ecosystems under global change and human disturbances will be explored. Such research will be used to predict the successional trend, to establish the optimal management model, and to enhance ecological function of karst ecosystems.
The Guizhou Province is the center of the South China Karst; and Puding County is the center of Guizhou karst region. Within a total area of 1079.9 km2 in this county, the mountainous area accounts for 34.7%, the hilly area for 49.6%, and the plain and basin areas for 14.7%. The karst morphology is a typical plateau surface type of peak-clump depression. The exposed rocks are distributed everywhere. The black limestone soil (Rendzina, in FAO and China’s soil taxonomy classifications) is shallow and discontinuous with high heterogeneity, but rich in nutrients and calcium. However, soil water easily leaks out through the rock lacunas, thereby resulting in a specific drought if sufficient rainfall is lacking.
The karst topography, humid and warm monsoon climate, and specific edaphic and rocky microhabitats render the vegetation in this area different from other non-karst subtropical regions. Evergreen trees (accounting for ca. 65% of total species) mixed with a proportion of deciduous trees (35%) in the canopy and sub-canopy layers comprise the typical karst forest, a non-zonal soil climax that is widely distributed in subtropical China. However, the original evergreen–deciduous broadleaved mixed forest has almost disappeared because of human disturbances. Secondary subclimax karst (short) forests remain in protected or remote areas. When forests are degraded by human activity, thorn shrublands and tussocks dominate karst hills. The bare or less vegetation-covered karst terrain usually leads to significant rocky desertification, a landscape that exhibits sand desertification in arid Central Asia but covered by large rocks. This phenomenon is a serious environmental and social disaster in the South China Karst region.
Soil Processes and Ecological Services in the Karst Critical Zone (CZ) of Southwest China
- Karst topography is a landscape formed from the dissolution of soluble rocks such as limestone, dolomite, and gypsum.
- Covering extensive parts of Southwest China, Karst is a key landscape.
- Rapid and intensive land use change has caused severe ecosystem degradation during the last 50 years.
- The SPECTRA programme seeks to assist the sustainable development of one of the poorest regions of China: Guizhou.
- We investigate the integrated geophysical-geochemical-ecological and social responses of the CZO to past perturbations, along a gradient from undisturbed natural vegetation to extremely human-perturbed landscapes.
- Through explicit consideration of plant-microbe-soil and plant-microbe-rock interactions, we will identify the biological controls on nutrient availability (C, N and P), soil formation and loss in the CZO, to inform strategies for sustainable management of karst landscapes.
UK PI: Timothy Quine & Chinese PI: Dali Guo
Contact: Dr Sophie M. Green (s.green2@exeter.ac.uk)