Dr. Frank S. Gilliam, the professor of Biological Sciences from Marshall University (USA) visited South China Botanical Garden (SCBG), Chinese Academy of Sciences (CAS) during 11-15^th July 2011, under the invitation of Prof. Dr. MO Jiangming, the principal investigator of the Ecosystem Management Research Group of SCBG.

During this visit, Prof. Gilliam firstly made a field trip to Dinghushan Long-term Nitrogen Research Project, and then went to Heshan National Field Research Station of Forest Ecosystem for visiting another nitrogen-deposition-research base, accompanied by Prof. Mo Jiangming and Dr. LU Xiankai. To better develop research collaboration, the members of the research group and Prof. Gilliam had a thorough scientific discussion and communication by showing research reports. Prof. Gilliam gave a high appreciation of the on-going research projects and research achievements, and also gave some instructive suggestions. Gilliam and Mo further discussed the international cooperation in the future.

On 14^th July, Prof. Gilliam presented a lecture entitled "The Nitrogen (N) Homogeneity Hypothesis: How Excess N Affects Biodiversity of Temperate Hardwood Forests", which deeply attracted the attention of the related scientists and graduate students in SCBG. Meanwhile, there was a further scientific discussion.

Prof. Gilliam is an internationally well-known ecologist. He devotes himself to the researches of terrestrial ecosystem nutrient cycling, forest ecology, fire ecology and environmental pollution. He is one of the first scientists expanding researches on effects of nitrogen deposition on forest ecosystems. He is an experienced expert in forest community ecology, especially in secondary succession and the species dynamics of the herbaceous layer of forests. In 2010, he was honored as Program Chair for the 95th Annual Meeting of Ecological Society of America, Pittsburgh, PA. Now, he is the associate editor of Journal of Ecology, one of the most authoritative international academic journals on ecology.