Soil health-Microbial Nitrogen and Carbon cycling/greenhous gas emissions
The massive demand for N for crop production in combination with N losses, including nitrate leaching and gaseous loss (N2O, NO, NO2) via microbial nitrification and denitrification, is accelerating N deficiency in agricultural soils. However, the complex response of soil microbes to agricultural management poses a substantial constraint on the understanding and assessment of N losses, as well as their climatic impacts.
In this proposed project, I will investigate the effects of agricultural management (e.g., fertilization, crop rotation, tillage, irrigation) on the soil microbiome, as well as their activities related to nitrogen/carbon cycling and greenhouse gas emissions.
Ecosystem resilience/recovery-Biodiversity
Ranked as the third most diverse ecosystem globally, grasslands play a pivotal role in global food security, with North America's Great Plains alone contributing 25% of the world's grain and nearly 20% of its beef. However, the substantial exploitation of grasslands (i.e. grazing) emerges as a primary factor contributing to the decline in biodiversity, and this loss is expected to be further intensified by climate change. The consequences of this loss extend beyond biodiversity, affecting fundamental ecosystem functions, including carbon (C) sequestration, nitrogen (N) fixation, and greenhouse gas (GHG) production, which collectively contribute to the reduction in productivity due to decreasing soil fertility and the collapse of resilience across the entire ecosystem.
In this project, we propose to develop a biome-interaction-based model (Fig.1) encompassing aboveground herbivores, vegetation, and belowground soil microbiome to quantify grassland resilience, by conducting experiments in both field and laboratory settings.
Microbial assemble and their role on ecosystem functions
One of the fundamental goals of microbial ecology is to understand the controls on the distribution patterns and diversity of microbial communities, given that they play a significant role in ecosystem functions. However, these patterns are usually unpredictable at both spatial and temporal scales.
In this proposed project, I will explore the two research questions: (a) how microbes with different functional traits assemble in different ecosystems (e.g., wetland, grassland, forestry as well as dessert) across the globe; and (b) how these assembly processes contribute to their cooccurrence, diversity, and function redundancy.