黄河三角洲盐碱地混交林林下植被现状

Study on Understory Vegetation of the Mixed Plantations on Saline-Alkali Soil in Yellow River Delta

采用样方调查的方法,研究了黄河三角洲盐碱地不同混交林林下植被的种类、生物多样性、生物量及不同土壤盐分林下植被的生长状况。共记录到林下植被31种,隶属于14科31属,其中禾本科最多,为10种;1、3、7、22龄林下植被的优势种分别为芦苇和芦蒿、苦荬菜+灰菜+狗尾草、车前草、韩式隐子草;林下植被的物种并不丰富,生物多样性不高,且富集种少,稀疏种多,地上部分生物量皆大于地下;土壤盐分含量高时,林下植被以耐盐碱植物为主,反之亦然,且由于苦买菜和灰菜具有较强的适应能力,在4个不同土壤盐分含量下都有生长。

The species of understory vegetation in different mixed plantations, the biodiversity, biomass and growth status under different salt content in the soil in the saline-alkali area in Yellow River delta were studied by sample plot survey. Totally 31 understory plant species were recorded, which belonged to 31 genera and 14 families. Among which, there were 10 species from gramineous family, accounting for the largest proportion. The dominant species of understory vegetation in 1 a, 3 a, 7 a and 22a mixed plantations were Phragmites australis ＋ Artemisia selengensis , Ixeris polycephala ＋ Chenopodium album ＋ Setaira viridis , Plantago asiatica, and Cleistogenes squarrosa respectively. There were few understory vegetation species with low biodiversity, less enriched species and more sparse species. The aboveground biomass of the understory vegetation species was generally greater than that of the underground. The dominate species in the mixed plantations with high salt content were mainly the salt tolerant plant species, and vice versa. Because of the strong adaptability to different environmental conditions, Ixeris polycephala and Chenopodium album grew well on sites with four different salt content levels.