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Plant invasion is one of the most serious global problems, destroying ecosystem structure and function. With the severity of plant invasion, it is particularly important to understand the mechanisms of plant invasion in order to control and solve the problem. We summarized different mechanisms of plant invasion and the synergy among them, expounded the allelopathy, the plant-soil feedbacks, the reciprocal symbiosis, the effects of plant functional traits and phenotype plasticity in the process of plant invasion, and comprehensively analyzed the synergy of multiple mechanisms on plant invasion trajectory. According to the results, the invasion trajectory of alien plants in the invasive site was divided into four stages: introduction, colonization, establishment, and invasion. Integrating all kinds of obstacles and promoting factors encountered into it and putting forward the invasion curve of plants would contribute to the future research and management of invasive plants. We further highlighted the current research deficiencies and future research directions and objectives based on analyzing current research methods of plant invasion.

In order to determine the toxicity of antibiotics and anaerobic digestion intermediates on anaerobic treatment of pharmaceutical wastewaters containing antibiotics, the single and joint toxicities of some antibiotics and intermediates to Photobacterium phosphoreum were tested by using the 15-min half inhibitory concentration (15 min-IC50) at pH = 7.00 +/- 0.05. The results showed that the 15 min-IC50 of ethanol, acetate, propionate and butyrate were 19.40, 20.71, 10.47 and 12.17 g x L(-1), respectively, which indicated that the toxicity descended in the order of propionate, butyrate, ethanol and acetate. The 15 min-IC50 of Amoxicillin, Kanamycin, Lincomycin and Ciprofloxacin were 3.99, 5.11, 4.32 and 5.63 g x L(-1), respectively, so the toxicity descended in the order of Amoxicillin, Lincomycin, Kanamycin and Ciprofloxacin. Using equal effect mixing method, the joint toxicity of four anaerobic digestion intermediates, the four intermediates together with Amoxicillin, Ciprofloxacin, Kanamycin, Lincomycin individually and all together were investigated, which demonstrated that the first three interactions were additive and the last three were synergistic. The observations have laid a foundation for control and optimization of anaerobic biotechnology for pharmaceutical wastewater containing antibiotics.