新疆呼图壁绿洲外缘的盐节木（Halocnemum strobilaceum）及其群落的生物生态学特征

盐节木株丛矮小，高约２０－４０ｃｍ；５月底至８月底净生长高度约３ｃｍ。侧根发达，主要分布在土壤由表层往下水分含量急增、多数情况下盐分逐步降低的２０－４０ｃｍ的土层内，几乎与地表平行伸展，有的长达３ｍ以上。盐节木群落为多汁盐柴类半灌木荒漠中的一个群系。本区记载有８个群丛，分布在地下水位１．０－１．７ｍ、表土层含盐量为４％－８％的盐土上。种类组成贫乏，群落结构简单，总覆盖度３０％－５０％，生物量１０００－２０００ｋｇ／ｈｍ￣２。群落中盐节木、有叶盐爪爪（Ｋａｌｉｄｉｕｍｆｏｌｉａｔｕｍ）具有很高的Ｎａ、Ｓ含量，分别在５００００ｍｇ／ｋｇ、１００００ｍｇ／ｋｇ以上；Ｎａ／Ｋ、Ｎａ／Ｃａ、Ｓ／Ｐ比值为８．５－２６．０，其它植物为１左右；植物中的Ｃａ／Ｍｇ比值为１．０－１．６。盐节木６种元素含量的季节变化，Ｎａ呈增高趋势；其变化曲线与Ｃａ、Ｍｇ相反；Ｎａ、Ｓ曲线相似。盐节木水提取液中具有高的Ｃｌ￣－、含量，ｐＨ为６．６６－６．８４。盐节木群落广泛分布在绿洲外缘的盐碱地上。在盐碱地改良、防止风沙、保护绿洲、牲畜冬春放牧等方面，具有重要的生态经济意义。

THE BIOECOLOGICAL CHARACTERISTICS OF HALOCNEMUM STROBILACEUM AND ITS COMMUNITY ON THE BORDER OF OASIS IN HUTUBI , XINJIANG

alocnemum strobilaceum is a low and small clump with 20-40cm in height; its netgrowth height is about 3. 0cm from the end of May to the end of August. The well-developedlateral roots that distribute mainly in the soil layer about 20- 40cm in which the saline con-tent decreases gradually in most cases and moisture content increases dramatically are almostparallel with the earth's surface in some cases reach more than 3m in length.The community of Halocnemum strobilaceum is a formation on the temperate s...