Research Topics

Overview

Soil Heterogeneity

Heterogeneity is an intrinsic character of soil environments.  Soil heterogeneity has important biological, biogeochemical and hydrological implications for processes such as soil erosion, bush encroachment and desertification. We are interested in using empirical and modeling approach to study spatial patterns of soil carbon, nitrogen, micronutrients, water and their corresponding isotopes and explore the underlying mechanisms of the observed spatial patterns.

Our group is interested in applying stable isotopes to the study of vegetation water source, nutrient source, root uptake patterns, soil distribution, nitrogen mineralization and much much more. We are also interested in developing novel methods to measure and utilize stable isotope to understand various system processes.

Evapotranspiration Partition

Globally, evapotranspiration (ET) accounts for about 65% of rainfall input and this number can be up to 95% in water-limited systems. ET comprises of evaporation and transpiration, and is controlled by different mechanisms. Separating evaporation and transpiration has always been a challenging task especially at large spatial scales due to technical constraints. We are interested in using stable isotopes as a major tool to separate evapotranspiration at various spatial and temporal scales and studying the controlling factors of ET partition. We are also interested in how future climate change will impact the partition.

Vegetation and Environments

We are interested in how soil moisture and nutrients as well as other biotic and abiotic factors (e.g., fire, grazing) affect the vegetation dynamics. More interestingly, scientists start to realize the important role vegetation plays in modifying the microclimate surrounding them, i.e. vegetation provides strong feedbacks to their living environments.

Stable Isotope Applications

The research work of our lab group focuses on the interactions between soil, water and vegetation in various environments, especially the water-limited systems. Stable isotope is our major approach in addition to a variety of other tools, including manipulative experiments, field observations, geostatistical methods, greenhouse experiments  and modelling to tackle these interactions.  We are also interested in working on developing new tools to study these processes. The followings are some of the main research areas.