Status quo and trends of biological invasion into China.
Combining literature review, filed survey and expert consultation, investigations were carried out of invasive alien species (IAS) in forest, wetland, grassland, desert, inland water and ocean (sea) ecosystems of China. A total of 488 IAS were identified with detailed information collected including name, taxonomy, distribution, origin, location and time first detected or introduced, pathway, hazard, nutrient circumstance, and habitats. Of the 488 IAS, 265 were plants, 171 animals, 26 fungi, 12 vira, 11 procaryotes and 3 protists. Analysis of the invasion years of the 392 IAS that have specific records reveals that only 31 IAS came in before 1850 and the number of IAS has been increasing steadily since 1850, especially since 1950. During the 60 years after 1950, 209 IAS appeared. Their debuts occurred mainly in the coastal regions and border provinces, like Yunnan Province and Xinjiang Uyghur Autonomous Region, but the stage tends to be moving northward. The percentage of intentional introduction almost equaled to that of unintentional introduction, but the latter has become the primary in recent years. America, Europe and other parts of Asia are the main origins of IAS of China. The number of IAS presents a decreasing trend from coastal regions towards inland.