北方草甸群落结构和组成分析及野花组合模拟构建

Analyses on structure and composition of northern meadow community, and simulated construction of wildflower combination

依据基于植物性状的群落构建机制,对位于晋冀交界处的典型北方草甸群落的垂直结构和多样性以及不同亚层物种的叶级谱、叶片形状、叶倾角、叶片数和冠（丛）径进行统计分析,并据此采用“盒子”模型对群落垂直剖面进行模拟构建;此外,根据中国北方草甸常见的野生植物种类提出了不同层次适宜配置的种类。结果表明：根据株高可将草甸群落划分为3个亚层,其中第2亚层的种数、株（丛）数、重要值、Shannon-Wiener多样性指数、Pielou均匀度指数和Gleason丰富度指数均最大,第1亚层的各项指标均最小;同一重要值等级下,第2亚层植物的冠（丛）径最高、第1亚层的最低。第1亚层植物茎型为直立且不分枝或少分枝,第2亚层植物以丛生茎型为主,第3亚层植物以匍匐状或莲座丛状为主。3个亚层的植物均以小叶型为主;第1亚层植物均具3-10枚叶片,叶片一般兼具茎生叶和基生叶,茎生叶主要为卵形和披针形,且以斜叶型（叶倾角30°-60°）为主;第2亚层以具3-10枚和11-30枚叶片的植物为主,线形、披针形、卵形和阔卵形叶片均存在,且以斜叶型为主;第3亚层以具3-10枚叶片的植物为主,叶片有阔卵形、卵形和披针形,且均为平叶型（叶倾角约90°）。根据各亚层植物性状,用长宽比较大的长方形“盒子”模拟第1亚层,用正方形“盒子”和长宽比小于第1亚层的长方形“盒子”模拟第2亚层,用长宽比最小的长方形“盒子”模拟第3亚层,据此构建北方草甸群落垂直剖面的“盒子”模型。根据该模型,人工野花组合群落适宜的配比为高大的植物种类占20%、中间层次种类占50%、低矮种类占30%,其种数和株（丛）数可因景观需求和立地条件而异。

According to community construction mechanism based on plant traits, vertical structure and diversity of typical northern meadow community located at border of Shanxi Province and Hebei Province and scale spectrum, shape, inclinatiorL angle, number of leaf and crown （tuft） diameter of species in different sub-layers were statistically analyzed, and hereby, community vertical section was simulated and constructed by ＂ Box＂ model. Besides, suitable configuration species in different sub-layers were proposed based on common wild species in meadow of North China. The results show that according to plant height, meadow community can be divided into three sub-layers, in which species and individual （tuft） numbers, important value, Shannon-Wiener diversity index, Pielou evenness index and Gleason richness index of the second sub-layer are the biggest, and those of the first sub-layer are the smallest. At the same grade of important value, crown （tuft） diameter of species in the second sub-layer is the highest, and that in the first sub-layer is the lowest. Stem type of species in the first sub-layer is erect with no or less branch, that of species in the second sub-layer is mainly cespitose, and that of species in the third sub-layer is mainly stoloniferous or rosette. Leaf of species in three sub-layers is mainly microphyll type. In the first sub-layer, leaf number of species all is the range of 3-10, with both cauline leaf and basal leaf, shape of cauline leaf is mainly ovate and lanceolate, and mainly oblique leaf type （leaf inclination angle 30°-60°）. In the second sub-layer, leaf number of species is mainly the range of 3-10 and 11-30, leaf shape is linear, lanceolate, ovate and broadly ovate, and mainly oblique type type. In the third sub-layer, leaf number of species is mainly the range of 3-10, leaf shape is broadly ovate, ovate and lanceolate, and all are flat leaf type （leaf inclination angle about 90°）. Based on characters of species in each sub-layer, rectangle ＂Box＂ with the larger ratio of length to width is used for simulating the first sub-layer, square ＂Box＂ and rectangle ＂Box＂ with ratio of length to width smaller than that of the first sub-layer are used for simulating the second sub-layer, rectangle ＂Box＂ with the smallest ratio of length to width is used for simulating the third sub-layer, hereby, ＂ Box＂ model of vertical section of northern meadow community is constructed. According to this model, suitable configuration of artificial wildflower combination community is 20% of high species, 50% of middle height species, and 30% of low species, and their numbers of species and individuals （tufts） can vary with landscape demand and site condition.