| 摘要: |
| 在适宜土壤水分(田间持水量的70%)、中度干旱(田间持水量的55%)和严重干旱(田间持水量的40%)3种土壤水分条件下,研究了油松(Pinustabulaeformis Carr.)苗木生长及水分利用特征。结果表明,随着土壤含水量的降低,油松叶水势、叶含水量、生长速率显著下降。油松枝条的快速生长和干物质迅速积累时期主要集中在4～5月;总耗水量和总生物量的大小顺序为:适宜水分>中度干旱>严重干旱;水分利用率(WUE)则表现为中度干旱最高,严重干旱最低;在适宜水分条件下油松的日、旬、月耗水量明显高于中度干旱和严重干旱处理;3种土壤水分处理下,油松耗水高峰期均为5～8月,最高旬耗水量均在7月上旬,最高耗水日均在7月5日,但在不同土壤水分条件下其耗水日进程存在差异;在中度干旱和严重干旱条件下,SOD活性呈现先升后降的规律,在严重干旱条件下,SOD活性高峰期维持时间较短;3种处理下的K+含量在胁迫后期均高于胁迫初期,表明K+含量与油松抗旱性有一定的相关性。 |
| 关键词: 油松 土壤干旱 苗木生长 水分利用率 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金项目(90302005)；中国科学院知识创新基金项目(KZCX1-06)。 |
|
| Growth and water comsuption characteristics of Chinese pine under soil drought stress |
|
|
| Abstract: |
| Under three soil water levels,which are fitted soil water content,medium drought and serious drought，and account for about 70%,55% and 40% of field capacity （θf）respectively,we studied Chinese pine (Pinus tabulaeformis)′s water consumption and water use characteristics.The result showed that water potential,water content,growth rate decreased significantly with the soil water content decrease.The period of fast growth and maximal biomass accumulation of Chinese pine were mainly in April and May.Total water consumption and biomass and growth were all fitted soil water contents>medium drought>serious drought.But total water use efficiency was highest at medium drought level，lowest at serious drought level.For three soil water contents，the highest water consumption in a month of Chinese pine was in May and August.The highest water consumption of ten days in a month was in the first ten days of July.The highest water consumption day was in July 5.The changes of water consumption in a day were different at three levels of soil water content.Superoxide dismutase (SOD) activity of Chinese pine went up under medium drought and serious drought but kept short time in serious drought.K+ content of Chinese pine was higher in the last growth stage under three treatments of soil water content.It showed the relationships ware bigger between K+ content and drought resistant adaptability of Chinese pine. |
| Key words: Chinese pine (Pinus tabulaeformis) soil drought seedling growth water use efficiency |
