Research

Despite ecology being extremely complex and context dependent, it is those general theories and principles that greatly enhanced our understanding of ecology and moved our field foward. Searching for the universalities in ecology is the core of my research philosophy. Thus, my research often spans different subfields of ecology in different study systems across distinct environments. Below are some of the research themes I focus on recently.

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Temperature dependence of carbon flux

Temperature dependence is a general property of almost all biogeochemical processes. Practically, the temperature dependence of ecosystem carbon flux is a critical quantity to resolve the uncertainty in the predicted climate–carbon feedback. I study the temperature dependence of carbon flux in various types of ecosystems. As part of the Scale, Consumer, and Lotic Ecosystem Rates (SCALER) project, I use diel dissolved oxygen data collected from seven distinct biomes to estimate the temperature sensitivity of stream metabolism and quantify the effects of warming on stream carbon balance. I also use high frequency soil respiration data collected in the Tibet alpine grasslands and soil incubation experiments to investigate how temperature sensitivity of soil carbon flux may be influenced and feedback to climate warming.

Scale dependence of ecosystem processes

The ecological patterns one observes often depend on the spatial and temporal scale of observation. Understanding the scale dependence of ecological patterns is not only of theoretical interests, but aslo of practical value because scale of measurements may not always match the scale of intended application. Combining reach and chamber metabolism measurements and scale transition theory, I study how the physiology of photosynthesis and respiration and spatial heterogeneity in the biotic and abiotic envonrments may create disprepancies in metabolism across spatial scales. I also use theoretical analyses and numerical simulations to study how aggregation over time, space, and ecological organizations may influence the perceived tempeature sensitivty of soil respiration.

Statistical methods for ecology

Robust inference requires robust methods. Facing the complexity of natural systems and noises often observed in ecological data, developing robust methods for analyzing ecological data is critical. In my view, robust statistical methods should be built on the data generating mechanisms and explicitly consider the structure of uncertainty. Based on this central view, I have worked on developing methods for estimating nutrient uptake in streams based on solutes transport and refining computational methods for estimating aquatic ecosystem metabolism. Currently, I am working on evaluating and developing statistical methods for meta-analysis in ecology.