期刊
JOURNAL OF ARID ENVIRONMENTS
卷 46, 期 1, 页码 79-91出版社
ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD
DOI: 10.1006/jare.2000.0657
关键词
carbon assimilation; Mediterranean ecosystems; Mediterranean shrublands; plant water relations; shoot water potential; stem photosynthesis; summer-deciduousness
Seasonal changes in phenology, shoot demography and physiology of the summer-deciduous shrub Anthyllis cytisoides L. were monitored at a field site in semi-arid south-eastern Spain. Vegetative growth took place during the cool season and the shrubs were leafless for c. 3 months during the dry season. In shrubs which had been supplied with water since late spring, leaf and shoot growth continued in the summer. Photosynthetic rate was limited by low plant water status for most of the observation period. Maximum photosynthetic rates of 14 mu mol CO2 m(-2) s(-1) were measured in early April but then declined progressively to practically zero in early July. Shrubs supplied with water maintained the same maximum photosynthetic rate in June. Superimposed on the environmentally controlled seasonal variation in the photosynthetic rate was a change in the leaf to stem area ratio as a result of leaf development, senescence (decrease in leaf nitrogen) and abscission. Anthyllis cytisoides is a drought avoider with a predictable, but temporally variable resting period. At various times of the seasonal cycle, the summer-deciduous habit allows only limited phenological and physiological responses to temporally favourable environmental conditions, which constrains carbon gain and productivity. (C) 2000 Academic Press.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据