青藏高原16个灌木树种苗期生长特性研究

以青藏高原16个灌木树种的苗木为研究对象， 用固定样株定期观测的方法，观测苗高生长节律，建立苗高生长的Logistic 曲线方程，并结合观测时段内的气象资料计算出进入速生期的日最低气温阈值。结果表明:16个灌木树种的苗高生长期、速生期、进入速生期的日最低气温阈值分别为:红砂111 d、42 d、12.5℃；黄花木121 d、71 d、14.7℃；沙棘121 d、60 d、12.5℃；驼绒藜127 d、49 d、12.5℃；唐古特莸129 d、62 d、17.1℃；梭梭130 d、36 d、11.7℃；鲜卑花133 d、36 d、13.0℃；山蚂蝗133 d、45 d、13.2℃；砂生槐134 d、55 d、17.1℃；白刺花137 d、71 d、17.1℃；金露梅137 d、57 d、14.3℃；霸王137 d、59 d、11.2℃；江孜沙棘152 d、57 d、17.0℃；尼泊尔锦鸡儿155 d、56 d、13.5℃；云南沙棘159 d、52 d、14.0℃；锦鸡儿169 d、68 d、12.5℃。依据生长期和进入速生期的日最低气温阈值提出短生长期和低阈值的红砂、霸王和梭梭可用于寒冷干旱的荒漠或半荒漠区的生态恢复；中等生长期和中等阈值沙棘、驼绒藜、鲜卑花，山蚂蝗，金露梅，黄花木可用于温凉干旱气候的生态恢复；长生长期或高阈值的江孜沙棘，唐古特莸、锦鸡儿、尼泊尔锦鸡儿、云南沙棘、白刺花和砂生槐则适宜于温凉干燥气候的生态恢复。

Growth Characteristics of 16 Shrub Species at Seedling Stage in the Qinghai-Tibet Plateau

Growth characteristics of 16 shrub species growing at seedling stage in the Qinghai-Tibet Plateau were studied by the method of regular observation for site fixed individuals. The rhythm of the growth of seedling height was observed，and related Logistic curve equation was established. The daily minimum temperature threshold at fast-growing period was calculated combining with the weather data at observation period. Three data related to each species were obtained respectively, such as duration of seedling height growth, fast-growing period, and daily minimum temperature threshold: Reaumuria songarica: 111 d, 42 d, and 12.5℃; Piptanthus concolor: 121 d，71 d，and 14.7℃; Hippophae rhamnoides: 121 d，60 d，and 12.5℃；Ceratoides lateens: 127 d，49 d，and 12.5℃；Caryopteris tangutica: 129 d，62 d，and 17.1℃；Haloxylon mmodendron: 130 d，36 d，and 11.7℃；Sibiraea laevigata: 133 d，36 d，and 13.0℃；Psilopeganum sinense: 133 d，45 d，and 13.2℃；Sophora moorcroftiana: 134 d，55 d，and 17.1℃；Sophora davidii: 137 d，71 d，and 17.1℃；Potentilla fruticosa: 137 d，57 d，and 14.3℃；Sarcozygium xanthoxylon: 137 d，59 d，and 11.2℃；Hippophae gyantsensis: 152 d，57 d，and 17.0℃；Caragana sukiensis: 155 d，56 d，13.5℃；Hippophae rhamnoides subsp. yunnanensis: 159 d，52 d，14.0℃；Caragana chinghaiensis: 169 d，68 d，and 12.5℃. Based on the three data, shrub species suitable to be used for ecological restoration in different regions were suggested. Species with short growing period and low threshold temperature would be suitable for the arid and semi-arid areas with cold and dry climate: R. songarica, S. xanthoxylon and H. mmodendron; H. rhamnoides, C. lateens, S. laevigata, P. sinense, P. fruticosa and P. concolor that had medium growing period and temperature threshold would be suitable for the arid areas with moderate climate; H. gyantsensis, C. tangutica, C. chinghaiensis, C. sukiensis, H. rhamnoides subsp. yunnanensis, S. davidii and S. moorcroftiana with long growing period and high temperature threshold would be the choice for at the areas with cool and dry climate.