Ecological Environment Effects Of Different Vegetation Restoration Models In Coastal Sand

In order to discuss the ecological improvement effects of vegetation restoration in coastal sandy land and explore suitable vegetation restoration models,the determination of shrub-grass protection vegetation restoration mode(?),trees-shrub-grass protection vegetation restoration mode(?),pure forest protection vegetation restoration model(?),shrub-grass landscape vegetation restoration model(?)and trees-shrub-grass landscape vegetation restoration model(?)and CK grassland restoration model.Investigated the microclimate factors,soil respiration rate,soil physical and chemical properties,soil enzyme activity and soil microbes of the six models of grass landscape vegetation restoration model.Using a combination of field investigation and indoor analysis,comprehensively compare the effects of different vegetation restoration models on the ecological environment,study the internal relationships between vegetation restoration models and vegetation factors,microclimate,and soil factors,and use principal component analysis and fuzzy mathematics.The membership function method comprehensively evaluates the ecological improvement effects of different vegetation restoration models.The results are as follows:1.In terms of adjusting the microclimate,both shrub-grass and arbor-shrub-grass vegetation models have certain advantages.Among them,the protection type significantly reduces the air temperature in the forest,and the landscape type has a significant effect in regulating the temperature difference between day and night;the tree-shrub protection type(?)and the landscape type(?,?)have more comfortable air humidity.2.In terms of soil physical properties,the effects of vegetation restoration models on improving soil bulk density and porosity are not significant,and further long-term research is needed.In terms of improving soil water content and water holding capacity,the tree,shrub and grass protection type(?)has the best effect,and the protection type is better than the landscape type on the whole.3.The overall improvement effect of soil chemical properties is better,and each restoration mode is greater than the grassland restoration mode(CK).The soil chemical properties of different vegetation restoration models in the same soil layer are significantly different.The overall performance is tree,shrub and grass protection(?)> shrub and grass landscape(?)> shrub and grass protection(?)> tree,shrub and grass landscape(?)>Pure forest protection type(?)>CK.4.The artificial assisted vegetation restoration mode can promote the activities of urease,invertase,hydrogen peroxide and phosphatase in the soil,but has no significant effect on the regulation of protease activity.The overall performance of the soil enzyme activity of different vegetation restoration models is: tree-shrub protection(?)> shrub-grass landscape(?)> tree,shrub-grass landscape(?)> shrub-grass protection(?)> pure forest Protection type(?)>Grassland recovery mode(CK).5.The total amount of soil bacteria,fungi and actinomycetes in different models is from high to low: tree,shrub and grass protection(?)> pure forest protection(?)> tree,shrub and grass landscape(?)> shrub and grass landscape type(?)>Shrub-grass protection type(I)>Grassland restoration model(CK),it can be seen that the protection type promotes the increase of the number of microorganisms significantly higher than the landscape type.6.Soil respiration affected by temperature is highest in summer and lowest in winter.The shrub-grass landscape type(?)has the strongest soil respiration rate,and its herbaceous biomass is the largest.It is not blocked by tall trees and receives a lot of photosynthetically active radiation,which makes the shrubs and herbaceous plants thrive in the plot and the microorganisms and roots respiration are active The soil respiration rate is stronger than other modes.According to the comprehensive evaluation,the ecological functions of different vegetation restoration modes are: Tree-shrub-grass protection restoration mode(?)>Shrub-grass prevention restoration mode(I)> Pure forest protection restoration mode(?)>Tree-shrub-grass landscape restoration mode(?)> Shrub-grass landscape restoration mode(?)> Grassland restoration mode(CK).Compared with the grassland model of natural restoration,the ecological benefits of each vegetation restoration model are significantly higher,and the protection type of each vegetation model is better than the landscape type as a whole.