【作者】 王艳；

【导师】 董厚德；

【作者基本信息】 东北林业大学 ， 植物学， 2001， 博士

【摘要】 本文在国内首次对结缕草的生物学和种群生态学进行了比较系统的研究，结果如下： 1.系统地研究了结缕草的形态及解剖结构，揭示出其耐旱、耐践踏、弹性好的生物学和解剖学基础。 2.对结缕草叶构件种群进行了研究，发现结缕草开始生长的生物学零度和休眠前叶片开始变色的低温敏感点均为10℃；结缕草分蘖展叶数目与有效积温之间呈幂函数关系；揭示了叶片出生及死亡的总体规律。 3.采用世代、形态2种方法对野生结缕草种群的年龄结构进行了研究，发现如果在获得关于分蘖形态与年龄相关的较为准确资料的基础之上，用形态方法划分结缕草无性系年龄结构更能反映出种群年龄构成的季节性动态。 4.人工结缕草种群匍匐茎的季节性扩展规律是从生长初期开始扩展速度逐渐加快，到7月末8月初达到最高值，然后呈逐渐下降的趋势。 在无邻体植物干扰条件下，单株结缕草无性系种群面积的扩展与扩展时间之间呈幂函数关系，面积增量与基础面积呈直线相关。 5.密度对单株结缕草无性系种群的影响主要表现在：随初始密度的减小，结缕草单株无性系种群的分形维数增大，表明其利用和占据资源的能力加强，因而结缕草无性系种群具有依外界条件而调节生长格局的生态适应性策略。这种策略还体现在：随可利用空间的扩大，匍匐茎的节间变长，节数增多，匍匐茎迅速伸长；分枝强度加大，子代匍匐茎数目增多，从而尽快地占据生态空间和资源。结缕草无性系对匍匐茎的资源投入比例随密度的减小而加大，以占据更多的水平空间；在密度大的条件下则增加对分蘖的投入比例，从而增强对垂直空间的占据能力。 6.在对结缕草种群有性繁殖进行的研究中发现：食物链对结缕草种子的萌发和传播具有重要作用，使种群得以大范围扩展；在一般贮存条件下，结缕草种子可在2年内保持较高的发芽率。 7.通过对结缕草种内变异问题的研究，总结出结缕草果穗长、每穗小穗数、千粒重几项指标由北向南、由沿海到内陆的变化规律和叶片秋季颜色随纬度变化的规律；从形态和酯酶同工酶角度进行的研究表明，结缕草种内存在着十分丰富的变异，并筛选出了几类具有实用价值的明显变异类型。 8.通过封育和放牧试验，提出了对结缕草种质资源进行生产性保护的新理论。更多还原

【Abstract】 This is the first time to study the biology and population of Zoysia japon.ica in China, and get some results as follows. 1. The morphological and anatomic characteristics of Zoysia japonica are studied in detail. The anatomic basis of drought and tramp resistance and good elasticity of Zoysia japoiica is discovered 2. The leaf梞odular population of Zoysia japonica is studied. Both the biological zero temperature for growth and sensitive temperature for color change of leaf are 10C. The relationship between leaf number and effective accumulative temperatures is power function. The general trend of birth and death of leaf is found. 3. The age structure of natural clonal population of Zoysia japonlca is studied by generational and morphological methods. The results show that if the relationship between age and tiller?s morphology has been found, the morphological method is better because it can show the seasonal change of age structure. 4.The seasonal expanding trends of rhizome in artificial populations of Zoysia j~iponica is that the expanding speed increases with time in the growing season and gets a maximum by the end of July and the beginning of August, thueuu the speed decreased. If there is no disturbance from other plant, which means the ecological space is large enough, the relationship between area梕xpanding of individual clouia] population and time is power function. The increment of area has a I inearitv relationship with basic area of the clone. 5.The influence of densities on individual elonal populations is studied. The fractal dimension value increases with the decreasing of density. The result shows the ability of clone to use and hold resources improves whueti density (Iecreases and cloinal population of Zoysia japonica could adjust growth pattern according t.o the environment. This is a kind of adaptable ecological policy. There are other phenomena to show the policy. When densit.y decreases, the internode of rhizomes becomes longer, node number increases, rhizome elongates quickly and ramification intensifies. So the clone could possess more space and resource. Clonal population of Zaysia japonica allocates more resource to rhizomes whetu density decreases so as to possess plane space but allocates more resource to tillers when density increases so as to possess more upright space. 6. An important influence of food chain for the spreading of Zoysia japonica population is found during the study of sexual reproduction. Seeds of Zoysiu japonica can reserve high germination rate within 2 years under normal condition. II 4? Then the rate decreases with time. 7. The variation within Zoysia japonica genus is studied. Some regular variations are found. The length of spike, spikelets number per spike and weight per 1000 seeds vary with latitude and the distance to sea. Leaf color in autumn changes with latitude too. Morphology and esterase isozyme researches show that there are many variations among populations of Zoysia japonica Some valuable ecotypes have been chosen. 8. A new theor germplasin resources protection by industrial production is put forward on the basis of grazing and enclosing experiments.更多还原