Research

Please check back here soon for an overview of where we work and what research topics are covered by our projects!

 

Project 1: Regulation mechanism of water transportation in mangrove trees.

Mangroves grow in the tropical and subtropical intertidal zones and experience high salt content in soil/water and soil hypoxia. Water in the xylem could be often under high negative pressure, inducing embolism and causing hydraulic dysfunction. Mangrove plant species can have different mechanisms to deal with salt, such as salt-secretion, salt exclusion by roots and salt dilution by water in tissues in stems and leaves. We will investigate the relationship between hydraulic efficiency and safety (prevention to embolism) of leaves/stems, their microscopic and ultra-microscopic anatomical structure. We will also study the relationship between stomatal regulation and photosynthesis, and sap flow in mangrove trees with different salt management mechanisms. For Rhizophoraceae, we will examine both terrestrial and mangrove species. At present it is unclear whether xylem embolism routinely occurs in plants in the field. We will investigate this in depth for mangrove trees.

Note: Light microscopes are available in our laboratory; scanning and transmission electron microscopes are available in our university.

Interested to collaborate or apply? Contact us! for more information.

 

Project 2: The evolution of hydraulic functions in stems and leaves and their correlation with photosynthetic capacity in basal angiosperms.

Angiosperms have become dominant in the majority of terrestrial ecosystems of the planet since the late Cretaceous, probably largely because of their high hydraulic efficiency, photosynthesis and productivity. However, little is known about the evolutionary trajectory of water transport system and relationships between structure and function in basal angiosperms. We will investigate the hydraulic structure, hydraulic efficiency and safety in stems and leaves, photosynthetic capacity, mechanical strength of basal angiosperms with different growth forms such as shrubs, trees, and lianas. Anatomical structure in leaves and woods will be analyzed with light, scanning and transmission electronic microscopes. We will test the heteroxylous hypothesis and analyze the trade-off between hydraulic efficiency, safety, and mechanical strength in basal angiosperms, the coordination in structure and function between stems and leaves, and characterize the evolutionary trend in hydraulic function of basal angiosperms. The outcomes of this project will also provide important information for the research on phylogeny of angiosperms, conservation and utilization of extant basal angiosperms, as well as ecosystem processes of palaeo-vegetations and succession of earth’s terrestrial environment.

Note: Light microscopes are available in our laboratory; scanning and transmission electron microscopes are available in our university.

Interested to collaborate or apply? Contact us! for more information.

 

Project 3: The coexistence mechanism of biodiversity in a tropical rain forest: linking plant phylogeny and function traits to species coexistence.

Tropical rainforest has the highest species diversity among terrestrial ecosystems, and as such, it is the ideal system to test hypotheses on species coexistence mechanisms. This project centers around the 20-ha forest dynamic monitoring plot of tropical rain forest in Xishuangbanna, Yunnan Province. We will measure functional traits related to water relations, carbon cycle and growth, seed dispersal and shade tolerance and other ecological processes from saplings, pole trees and the canopy trees of some selected plant lineages. With the trait data together with the community phylogeny established with the DNA barcodes, we will analyze community phylogenetic structure, differences in species occurrence response to environmental factors in the context with phylogeny, the contribution of which by functional traits and species repulsion, to reveal the maintenance mechanisms of biological diversity of a tropical rainforest community. A canopy crane in the site will be soon available to allow us measure the traits of forest canopy.

Interested to collaborate or apply? Contact us! for more information.

 

Project 4: Genomics, Historical Biogeography and Diversification of Asian and African Plant Lineages.

Tropical Asia contains at least six biodiversity hotspots (sensu Myers), and hosts more than one fifth of the worlds plant, animal and marine species. Perhaps best known by the general public for iconic elements like Rafflesia, Giant Aroids, Dipterocarpaceae, Orang Utan and Tigers, sadly, it’s also one of the most densely populated and most heavily deforested regions on the planet. Large areas of tropical Asia have been cleared of their native, ecologically complex and highly species rich ecosystems, only to have them replaced by monotypic plantation forests of oil palm, rubber, teak, tea and Eucalyptus. In contrast to other continents with sizeable tropical areas (Africa, South America) nearly the entire geographic area covered by tropical forests is contained within these hotspots, indicating the extent of damage done and threats to the persistence of the native biodiversity. In the 1970’s and ongoing to the early 1990’s, Asia became the world’s leader in the export of tropical timber with global market shares of over 70%. These events took place, while little was known about the origin, distribution and causes for biodiversity, diversification, centres of diversity etc. Aside from vastly outdated flora’s and incomplete checklists, it was not until being confronted with the consequences of major forest clearance, ecological damage and species extinctions that the notion of “biodiversity science” and the need for science-based conservation came to the fore.

In order for humanity to thrive and prosper, it will need to find ways to use biodiversity sustainably in a responsible and ethical fashion. This will require a fundamental understanding of life on earth, how, when and where it evolved, and how it’s species, ecosystems and abiotic properties interact with one another, and what our impact is on these systems. For this to become possible, we must make sure that sizeable areas of intact, complete and healthy ecosystems continue to exist, and we have to develop the scientific programs that will explore and study their environmental functioning and evolutionary history.

In this project, we focus our efforts at understanding the origin, rise and persistence of tropical plant biodiversity, with a strong focus on the six interconnected biodiversity hotspots of tropical Asia, and the flora of the Madagascar and Indian Ocean Island Biodiversity Hotspot. To achieve this, we use a combination of taxonomy, ecology, molecular systematics, historical biogeography and genomics to address a wide range of research topics, ranging from the construction of new regional floras and description of new species, reconstructing community assembly and in-situ diversification on oceanic islands and describing historical long-distance dispersal, to analysing genome-level diversification, studying the prospects for native plant community restoration and analysing the effects of palaeogeographic changes in landmass configuration in the Southern hemisphere on patterns of plant evolution.

Interested to collaborate or apply? Contact us! for more information.

 

Project 5: Climate resilience of seed germination and seedling establishment.

How seed germination and seedling developmental physiology of tropical and subtropical trees are affected by climate change is poorly understood, especially in marginal communities that exist in climatic transitional zones such as the subtropical to tropical transitional regions of Guangxi. Climate change scenarios predict higher frequency, intensity, and severity in drought periods for tropical regions and prolonged and more intense drought have already been observed in many parts of the world. If the generally expected inverse relationship between species’ shade tolerance and drought tolerance is true, we are likely to see a community level shift in species distribution that favors more drought-tolerant pioneer species at the loss of valuable timber species that are usually more shade tolerant. I am investigating how drought, light and temperature stress affects the survival and function of tropical and subtropical forest species, specifically during the seed germination and seedling development process. The focus will be on the species’ physiological responses related to carbon acquisition and hydraulic conductivity. In addition to providing fundamental knowledge on the mechanisms of carbon gain, water balance and transport, this research will be able to evaluate which strategically important resource species should be prioritized for food and resource security, conservation and climate adaptation strategies.

Interested to collaborate or apply? Contact us! for more information.

 

Project 6: Biophysics of seed water relations.

Water is the most crucial physical factor that affects seed viability during storage as well as during germination. Understanding the biophysical aspects of water during germination and storage are fundamental for developing a sound scientific basis for long term seed storage and predicting seed germination success after storage. For many seeds preservation or viability after storage depends on the seed moisture content as well as preservation temperature. Water uptake is an essential requirement for seed germination in any flowering plant seed. In addition, oxygen and an appropriate temperature are needed for mature, non-dormant seeds to complete germination. In minute dust seeds it is crucial that they gain sufficient amounts of water to counter large losses of net water across the seed coat (testa). Water relations are known to match species’ habitat requirements and hence allowing for better understanding conservation needs of especially threatened species. This project is designed to assess the factors that affect seed coat permeability to water, the effect of Absicic Acid on regulating internal water in seeds and to determine how mobilization of storage resources affect different phases of germination.

Interested to collaborate or apply? Contact us! for more information.

Selection of project sites