以滨海滩涂盐地碱蓬〔Suaeda salsa （Linn.） Pall.〕的覆被度（VC）为标准划定低覆被区（30%＜VC≤50%）、中覆被区（50%＜VC≤80%）和高覆被区（80%＜VC≤100%），并以光滩区（0%≤VC≤30%）为对照，对各样地的盐地碱蓬生长指标和土壤理化指标进行测定，并分析了盐地碱蓬生长状况与土壤因子的相关性。结果表明：不同覆被区盐地碱蓬的总生物量、植株密度和株高均有显著（P<0.05）差异，但茎直径则无显著差异；随覆被度增大，盐地碱蓬的各项生长指标依次升高。各覆被区的土壤容重总体上显著低于光滩区，土壤的最大持水量、总孔隙度、毛管孔隙度和通气孔隙度总体上显著高于光滩区，其中，高覆被区的土壤物理性质变幅最大。随土层加深，各覆被区的土壤pH值总体呈升高趋势，但土壤的含水量和水溶性盐含量总体呈降低趋势；而各样地的各土壤养分含量总体呈不同的变化趋势。随覆被度增大，土壤pH值呈降低趋势，而土壤的含水量、水溶性盐和有机质含量总体呈升高趋势。与光滩区相比，各覆被区0~20 cm土层的土壤pH值和土壤全氮含量升高、土壤水溶性盐含量降低，各覆被区各土层的土壤有机质含量不同程度升高、土壤速效磷含量不同程度降低；此外，高覆被区各土层的土壤含水量及中覆被区各土层的土壤全氮含量均高于光滩区，各覆被区40~60 cm土层的土壤速效钾含量均高于光滩区。冗余分析结果表明：盐地碱蓬生长指标与土壤的容重和pH值呈极显著（P<0.01）负相关，与土壤的总孔隙度、含水量、有机质含量和全氮含量分别呈极显著或显著正相关。综合分析结果表明：相较于光滩区，盐地碱蓬覆被区的土壤结构明显改善，土壤的持水能力以及有机质和全氮的含量均不同程度升高；提示盐地碱蓬适度覆被有利于改善滨海滩涂土壤理化性质，提高土壤肥力，特别是对浅层土壤的理化性质有较大影响。

Using vegetation coverage （VC） of Suaeda salsa （Linn.） Pall. in coastal beach as a reference， the vegetation-covered areas were delimited into low vegetation-covered area （30%＜VC≤50%）， medium vegetation-covered area （50%＜VC≤80%） and high vegetation-covered area （80%＜VC≤100%）， and taking the bare land area （0%≤VC≤30%） as the control， the growth indexes of S. salsa and the physicochemical indexes of soil in each sampling plot were measured， and the correlations between growth status of S. salsa and soil factors were analyzed. The results show that the total biomass， plant density and height of S. salsa in different vegetation-covered areas are significantly （P<0.05） different， but the stem diameter shows no significant difference； with the increase of vegetation coverage， each growth index of S. salsa increases successively. The soil bulk density in each vegetation-covered area is generally significantly lower than that in bare land area， while the maximum moisture capacity， total porosity， capillary porosity and aeration porosity of soil are generally significantly higher than those in the bare land area， in which， the soil physical properties in the high vegetation-covered area have the largest variation degrees. With the deepening of soil layer， the soil pH value in each vegetation-covered area shows a tendency to increase in general， but the water content and water soluble salt content in soil show a tendency to decrease in general； while each soil nutrient content in each sampling plot all shows different variation tendencies in general. With the increase of vegetation coverage， the soil pH value shows a tendency to decrease， while the water content， water soluble salt content and organic matter content in soil show a tendency to increase in general. Compared with the bare land area， the soil pH value and soil total nitrogen content of 0-20 cm soil layer increase， while the soil water soluble salt content decreases， soil organic matter content of each soil layer increases while soil available phosphorus content decreases to different degrees in each vegetation-covered area； in addition， the soil water content of each soil layer in the high vegetation-covered area and the soil total nitrogen content of each soil layer in the medium vegetation-covered area are all higher than those in the bare land area， the soil available potassium content of 40-60 cm soil layer in each vegetation-covered area is higher than that in the bare land area. The redundancy analysis result shows that the growth indexes of S. salsa show extremely significant （P<0.01） negative correlations with the bulk density and pH value of soil， and show extremely significant or significant positive correlations with the total porosity， water content， organic matter content and total nitrogen content in soil. The comprehensive analysis result shows that compared with the bare land area， the soil structure of vegetation-covered areas of S. salsa is obviously improved， and the water holding capacity and contents of organic matter and total nitrogen of soil increase to different degrees； it is indicated that appropriate coverage of S. salsa is beneficial to improve the physicochemical properties and fertility of soil in coastal beach， especially has a great influence on the physicochemical properties of the shallow soil.