Summary comments on assessment methods of ecosystem integrity for national parks.
National parks are one of the foundations of global biodiversity conservation and help protect the ecological environment and biodiversity. Assessing ecosystem integrity in national parks can help understand ecosystem balance, health, and biodiversity status. We introduce three methods to assess ecosystem integrity of national parks: IBI (Index of Biotic Integrity), TLA (Three Level Approach) and EIAF (Ecosystem Integrity Assessment Framework), respectively. IBI relies on high intensity field survey and laboratory analysis. Albeit expensive, time consuming and requiring high level of biological expertise in identifying species, the results are accurate and reliable. TLA, including Remote Assessment, Rapid Assessment and Intensive Assessment, offers great flexibility to assess the integrity of complex ecosystems. EIAF combines the advantages of IBI and TLA, expands the use of indicator species and optimizes scoring statistics. Hence, EIAF is one the most sophisticated assessment methods of ecosystem integrity for national parks. We also discuss some issues such as incomplete assessment indices, single assessment form and subjectivity of assessment methods in current studies. We propose that research on ecosystem integrity of national parks should combine the processes that join nature, economy and society. Such an interdisciplinary approach requires integrated research on sustainable socio-economic development and human health, and explore the relationship between invasive species and ecological environment. We also suggest the need to look for new indicator species that can reflect the state and change trend of ecosystem integrity and thus help develop a standardized assessment system for national parks.