Zhang Mingxiang "The People**
December 11, 2023 13th edition).
Due to its strong invasion, Spartina alterniflora continues to expand in the coastal areas of China, destroying the ecological balance. For the treatment of Spartina alterniflora, researchers at home and abroad have explored a number of measures such as physical control, pharmaceutical treatment, and biological control.
Recently, the second national Spartina alterniflora control site meeting was held in Dongying, Shandong Province, to summarize and exchange the effectiveness and experience of Spartina alterniflora control. What kind of grass is Spartina alterniflora? Why a special meeting was held to discuss its control?
Spartina alterniflora belongs to the Poaceae family, is a perennial halophyte herbaceous plant with a well-developed root system, can penetrate more than 1 meter deep into the ground, and has the characteristics of high photosynthesis efficiency. Spartina alterniflora has a strong aerated tissue, the leaves have salt glands, and most of the salt absorbed by the roots is excreted by the salt glands, so it is resistant to flooding and salt. However, Spartina alterniflora is poor drought tolerant and can only grow in the intertidal zone along the coast.
In addition to its strong growth ability, Spartina alterniflora also has a strong reproductive ability. After the mature seeds fall off, they can drift around with the wind, waves, and tides, and once they encounter a suitable growth environment, they can take root and sprout, and spread rapidly through rhizome propagation.
The origin of Spartina alterniflora is in the Americas, and it was introduced to China in the 70s of the 20th century, and plays a certain role in protecting beach berms, promoting land siltation, and slowing down coastline erosion. However, due to its strong invasiveness, Spartina alterniflora continues to expand in the coastal areas of China, and the population area continues to grow, mainly distributed in Shanghai, Jiangsu, Zhejiang, Fujian, Shandong and other places. The invasion of Spartina alterniflora not only reduces the biomass and biodiversity of native species in China's coastal wetlands, destroys the ecological balance, but also causes the silting of waterways and the occupation of tidal flats. Spartina alterniflora was included in the List of the First Batch of Invasive Alien Species in China and the List of Key Management Invasive Alien Species.
For the treatment of Spartina alterniflora, researchers at home and abroad have explored a number of measures such as physical control, pharmaceutical treatment, and biological control. Physical control includes measures such as mulching and shading, mowing, ploughing, fire, flooding, etc., but it is time-consuming and laborious, the environmental disturbance is large, and the rate is high. Pesticide treatment refers to the application of herbicides to kill plants, but the treatment effect is greatly affected by factors such as wind, tidal cycle, and the waxy layer covered by plant stems and leaves, and will bring environmental pollution risks. Therefore, the selection of high-efficiency, low-toxicity and low-residue agents is a difficult point to be broken through in the large-scale application of pharmaceutical treatment. However, the effect of biological control is long-lasting, and the impact on the environment is small, and there are currently ways to introduce natural enemies and biological substitution control.
At present, the management of Spartina alterniflora in China has achieved phased results. Liaoning, Fujian, Shandong, Hainan and other places have completed the removal of Spartina alterniflora in the whole area, and have fully transferred to the stage of management and ecological restoration. In order to achieve effective control of Spartina alterniflora, extensive public participation is required. If the public finds Spartina alterniflora, they can report it to the relevant departments in a timely manner.
The author is a professor at Beijing Forestry University, secretary-general of the Nature Reserve Research Center of the National Forestry and Grassland Administration, and interviewed by Dong Siyu, a people's first reporter).