PARTNERS: University of Wisconsin-Madison, Brown University, University of Missouri-St. Louis, U.S. Geological Survey (USGS), USGS-EROS Data Center, South Florida Water Management District, Chinese Academy of Sciences, University of California-Berkeley, University of Hong Kong, Taiwan National University, University of Georgia, other Forest Service units 

SUMMARY: It is commonly believed that more diverse habitats are less invasible due to niche occupation. However, recent evidence shows that invasibility is a much more complex issue and may be determined by multiple factors. Invasibility tends to be the highest when the existing biomass is the lowest. Also, habitat invasibility changes over time. For better control and management, future research should focus more on the mass dominance of a few trule invasives rather than total number of exotics in a habitat. Currently, Southern Research Station scientists working with the Eastern Forest Environmental Threat Assessment Center (EFETAC) are collecting metadata regarding various habitat characteristics and invasibility from diverse ecosystems in U.S. forests, other ecosystems, and around the world to further test the generality of the above conclusions. The researchers ask the following questions: (1) What kinds of habitats/communities are most invasible and whether such invasibility is associated with disturbance (including land use), landscape configuration, and habitat traits? (2) Does biodiversity help resist biotic invasion, and if so, how? And (3) How does climate change in the future affect the spread of invasive species? 

Preliminary observations show that species-rich communities are invasible but may be so at a lesser degree, although individual component species can show highly invader-specific resistance or promotion. However, species richness apparently does not work in isolation; it has to work with species mass abundance in either measuring or determining habitat invasibility. A community’s ability to preclude species invasions may be dependent upon a threshold level of both species richness and abundance, below which the importance of species interactions is only a weak force. Comparisons among the major community-types within and among geographic regions in the future can provide new insights for both invasion biology and management.

STATUS: Ongoing

PROGRESS:

Miao, S.L., Y. Li, Q. Guo, H. Yu, J. Ding, F. Yu, J. Liu, X. Zhang, and M. Dong. In Review. Potential alternatives to classical biocontrol: Using native agents in invaded habitats and genetically engineered sterile cultivars for invasive plant management. Journal of Plant Ecology. 

Ren, H., S. Jian, H. Lu, Q. Zhang, W. Shen, W. Han, Z. Yin, and Q. Guo. 2008. Restoration of mangrove plantations and colonisation by native species in Leizhou bay, South China. Ecological Research 23:401-407. (PDF)

Guo, Q. and A. Symstad. 2008. A two-part measure of degree of invasion for cross-community comparisons. Conservation Biology 22:666-672. (PDF)

Chen, H., L. Chen, J. Li, T.P. Albright, Q. Guo, and L. Ma. 2007. Study on species invasion warning modeling using GIS and data mining. In Wang, Y., J Li, B. Lei, J. Yang, Eds. Remote Sensing and GIS Data Processing and Applications; and Innovative Multispectral Technology and Applications, Proc. SPIE 6790, 7 pp.

LINKS:

University of Wisconsin-Madison

Brown University

University of Missouri-St. Louis

U.S. Geological Survey (USGS)

USGS-EROS Data Center

South Florida Water Management District

Chinese Academy of Sciences

University of California-Berkeley

University of Hong Kong

Taiwan National University

University of Georgia

CONTACT: Qinfeng Guo, EFETAC Threat Assessment Team Ecologist, qguo@fs.fed.us or 828-257-4246