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This study investigated the distribution of exotic invasive plant Spartina alterniflora in mangrove nature reserve. Kandelia candel select representative indigenous, determination candel and Spartina alterniflora mature leaf photosynthetic characteristics, chlorophyll content, osmotic potential physiological characteristics of the membrane permeability of free water and bound water content, comparative analysis of both the intertidal with environmental factors with adaptability; habitat to set four plots, tracking the determination of the different growth stages in one growing season, the growth of Spartina alterniflora characteristics along Zhangjiangkou River upstream to the sea, explore intertidal Spartina alterniflora the relationship between the individual and community growth. Corresponding plots by manual transplanting candel hypocotyl regular surveys candel hypocotyl number and candel seedling growth explore Spartina alterniflora growth of community candel seedlings updated research results are as follows: 1. Zhangzhou Eguchi mangrove nature reserve along the river under different salinity gradient of Spartina alterniflora growth distribution, compared to the mangrove plants, Spartina alterniflora wide ecological amplitude, the salinity adaptation range is also wider (2 ‰ ~~ 30 ‰), and the different salinity has a different distribution, Spartina alterniflora can be adjusted to adapt to different environmental levels through its own phenotype plasticity. Under the same environmental conditions cross flower of Spartina leaves the net photosynthetic rate were higher than Kandelia candel, and the difference was highly significant (p lt; 0.01), in which the the candel distribution of the lower limit of the plot, Spartina alterniflora net photosynthetic rate is a candel 2.14 times; candel leaf transpiration rate and stomatal conductance as salinity increased speed dropped faster, and less than Spartina alterniflora; otherwise chlorophyll content of Spartina alterniflora than candel, the highest chlorophyll a content can reach 1.13 ± 0.15 mg.g of -1 ; Spartina alterniflora low osmotic potential, a minimum of only -3.50 ± 0.12Mpa, can be higher accumulated more penetration regulating substances salt environmental conditions, has strong penetration ability to regulate electrolyte leakage rate is higher than candel to reduce membrane damage suffered by its own regulation mechanisms, so as to adapt to the harsh environmental stresses ; moisture content of Spartina alterniflora and candel difference extremely significant (p lt; 0.01), higher than candel bound water content, better water retention capacity, relative to the mangrove plant, Spartina alterniflora have physiologically certain advantages, and it is precisely because of Spartina alterniflora physiological advantage may result in a competitive advantage with mangrove plants, enabling it to be successful invasion of mangrove communities. Spartina cordgrass spread of asexual reproduction, seedling stage is a period of rapid proliferation, Spartina alterniflora mangrove plants the distribution concentrated area, Spartina alterniflora diffusion distance in the seedling stage, up to 238 ± 20cm, the appropriate salinity (15 ‰) can promote the Spartina alterniflora breeding diffusion the high salinity above 25 ‰ significantly inhibit the diffusion of Spartina alterniflora breeding; soil organic matter content and Spartina grass growth was highly significant positive correlation (p lt; 0.01), salinity significantly inhibited the growth of Spartina alterniflora, Spartina alterniflora along the river increased salinity, plant height, basal diameter, leaf area are significantly lower in the high salinity of 25 ‰, Spartina alterniflora growth began to be greater inhibition; biomass per plant also showed a downward trend with the increase of salinity, but salinity 15 ‰ around Spartina alterniflora larger biomass per unit area, which indicates that the optimal range of salinity of about 15 ‰ Spartina alterniflora population growth. Candel hypocotyl bud growth generally in about a month, animal grazing, and the shoals of salinity, tidal movements, intertidal crabs will affect hypocotyl solid growth, the most upstream plots fixation rate is the highest of 97.5%, the most downstream sample ground of solid forward rate is only 22.5%; candel seedlings of the growth process, light is an extremely important factor, due to inter spend meters grass shade of, growth of K. candel seedlings of the lack of normal light of slow growth, stem slender, leaf chlorosis due to insufficient light part; reproductive stage in Spartina alterniflora All lodging candel seedlings due to the Spartina alterniflora lodging coverage completely lost the light, and eventually all died.
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