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生态学杂志 ›› 2011, Vol. 30 ›› Issue (06): 1091-1099.

• 研究报告 • 上一篇    下一篇

不同采收方式对富养化河道浮床空心菜生物产出的影响

贾悦,李秀珍**,唐莹莹,辛在军,郭文永,孙永光,何彦龙   

  1. 华东师范大学河口海岸学国家重点实验室, 上海 200062
  • 出版日期:2011-06-08 发布日期:2011-06-08

Effects of different cutting regimes on the productivity of Ipomoea aquatica Forsk planted on floating-mats in a eutrophicated river of Shanghai.

JIA Yue, LI Xiu-zhen, TANG Ying-ying, XIN Zai-jun, GUO Wen-yong, SUN Yong-guang, HE Yan-long   

  1. State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200062, China
  • Online:2011-06-08 Published:2011-06-08

摘要: 以浮床空心菜为研究对象,在过水河道条件下,研究了不同采收周期(14 d采收1次、21 d采收1次、28 d采收1次)和留茬高度(15 cm、25 cm、35 cm)组合对浮床植物生物产出的影响。结果表明:刈割后的植物仍能够适应过水河道环境,并在其生长周期内持续生长。经110 d的生长,分枝数提高了近5倍,最长根长27.55 cm,平均根长15 cm,根系直径达11 cm。单株根鲜重可达146 g,每平方米浮床根部可吸附颗粒物3.36 kg。新芽生长速率随采收次数增多,处理组均呈现先不断提高然后减小的趋势,变化幅度为0.54~3.7 cm·d-1,对照组为1.63 cm·d-1。适当刈割能提高新芽再生速率。单次收获生物量同新芽变化规律相似,即先逐渐增多然后减小,生物量增长速率变化幅度3.83~37.9 g·m-2·d-1。从总生物量来看,28 d采收1次留茬25 cm、35 cm组的生物量(干重)产出最高,达2112 g·m-2;从茎叶比看,每14 d采收1次3个留茬高度,及每21 d采收1次留茬15 cm和25 cm方式收获生物量茎叶比较佳。综合考虑产量、质量及浮床便捷管理,每21 d采收1次留茬15 cm的采收方式效果最佳,此时新芽平均生长速率1.88 cm·d-1,平均茎叶比<1,总生物量1966 g·m-2

关键词: 优势种群, 天然林, 生态位宽度, 生态位重叠, 生态位相似性比例

Abstract: This paper studied the effects of different combinations of cutting frequency (once every 14, 21, and 28 days) and stubble-remaining height (15, 25 and 35 cm) on the output of Ipomoea aquatica Forsk planted on floating-mats in a eutrophicated river of Shanghai. After cutting, the plants could still grow healthily during its whole lifecycle. The tiller number after 110 d growth was 5 times of the control, with the longest root length, average root length, and average root system diameter being 27.55 cm, 11 cm, and 15 cm, respectively. The fresh root biomass per plant was 146 g, and the roots per square meter floating mat could adsorb 3.36 kg suspended particulates. With increasing cutting frequency, the sprout growth rate had a trend of increasing first and decreased then, and the variation range was 0.54-3.7 cm·d-1, compared with 1.63 cm·d-1 of the control (no-cutting). Appropriate cutting could promote sprout growth rate. The biomass harvested per unit time had the similar variation trend as sprout growth, and the biomass growth rate was 3.83-37.9 g·m-2·d-1. The dry biomass output was the highest (2112 g·m-2) in treatments cutting every 28 days and stubble-remaining height at 25 cm and 35 cm, and the stem/leaf ratio was higher in treatments cutting every 14 days and stubble-remaining height at 15, 25, and 35 cm, and cutting every 21 days and stubble-remaining height at 15 cm and 25 cm. To comprehensively consider the biomass output and quality as well as the management convenience of floating-mats, cutting every 21 days and stubble-remaining height at 15 cm was the best cutting regime, under which, the average sprout growth rate was 1.88 cm·d-1, stem/leaf ratio was less than 1, and total biomass was 1966 g·m-2.

Key words: Dominant populations, Natural forest, Niche breadth, Niche overlap, Niche similarity