贝壳砂生境典型灌草植被的土壤水分生态特征

Soil Water Ecological Characteristics of Typical Vegetation Types in Sand Habitat Formed from Seashell

为探讨黄河三角洲贝壳堤岛典型灌草植被的土壤蓄水及持水性能,选取贝壳砂生境的酸枣(Ziziphus jujuba var.spinosa)、杠柳(Periploca sepium)和二色补血草(Limonium bicolor)3种典型植被,以裸地作为对照,测定分析不同植被类型下的土壤颗粒组成、水分物理参数和土壤水分特征曲线,以明确贝壳砂生境不同植被类型的土壤水分生态特征。结果表明:(1)贝壳砂生境下,不同灌草植被均具有减少石砾和粗砂粒、增加细砂粒和粉黏粒含量的作用,其中酸枣林可显著减少粗砂粒、增加粉黏粒含量;杠柳林可显著减少石砾、增加细沙粒含量;草本对减少粗砂粒和石砾含量、增加细沙粒和粉黏粒含量的作用较弱。(2)灌草植被可显著提高贝壳砂的蓄水能力,其中酸枣林最强,杠柳林次之,草本最差。0~30cm土层的有效含蓄量和含蓄降雨量均值均表现为酸枣林>杠柳林>草地>裸地。(3)0~30cm的酸枣林贝壳砂持水能力最强,杠柳林次之,草本最差;同一植被类型下0~15cm贝壳砂的持水能力显著高于15~30cm的持水能力。贝壳砂生境3种植被类型改善土壤物理性质及蓄水保土功能表现为灌木林优于草地,其中酸枣林的蓄持水分能力最强,杠柳林次之,草本最差。酸枣更适于贝壳砂生境退化生态系统的植被恢复。

In order to investigate soil water storage and hold capacity under typical shrub vegetations in sh- ell island, Ziziphz^s jujube var.spinose, Periploce sepium and Limonium bicolor located on the Yellow River Delta were analyzed in contrast with bare soil to determine the Soil particle composition, water physi- cal characteristics and soil water characteristic curves, to explore the water characteristic curve under dif- ferent vegetation types. The results show that： （1） Shrub and grass can reduce gravel and coarse sand con- tent, increase the content of fine sand and clay powder, including Z. jujube var. spinose can reduce the coarse sand significantly and increase clay content; P. sepium can reduce the gravel significantly and in- crease fine sand content; The role of herbs in the reduction of coarse sand and gravel content and increase of fine sand and powder clay content is weak. （2）Shrub vegetation can improve the soil properties and the effect of soil water storage ability, The sequence is as follows： Z. jujube var. spinosa^P, sepium~ grassland^bare land, reflected in the two indicators of effective rainfall and implicit rainfall. （3） The se- quence of water holding capacity is as follows： Z. jujube var. spinosa ~ P. sepium ~grassland~ bare land, and 0--15 cm soil water-holding capacity is more than 15--30 cm under the same vegetation type. The results show that the three kinds of vegetation types improve the soil physical properties and the function of water storage and soil preservation. The shrubs are better than the grassland, among which the Z. jujube var. spinosa is the strongest, and the grassland is the worst. Improving effects of the soil physical proper- ty, soil potential water storage and holding capacity of shell sand soil are evaluated as follows： Z. jujube var. spinosa^P, sepium^grassland^bare land. The results show that Z. jujube var. spinosa is more suitable for vegetation restoration in degraded ecosystem.