Abstract:[Background] The restoration of the vegetation in the water-level-fluctuating zone is widely valued by the public. This work is aimed to explore the physiological and structural adaptation mechanism of Cynodon dactylon and Morus alba surviving on the water-level-fluctuating zone. [Methods] The natural surviving C. dactylon and the two-year native M. alba (plant height in 1.5-2.0 m) at 171 m and 0,10 and 70 d after re-emergence of the water-level-fluctuating zone were sampled as the study materials. The C. dactylon and M. alba of the same age at 177 m without submergence were sampled as controls (CK). Their growth and physiological indexes (number of fibrous roots, diameter of root, stem length or height of a tree, internode length, number of branches, area of a single leaf, chlorophyll content, soluble sugar content, soluble protein content, free proline content, SOD activity, CAT activity, and root vitality) as well as the anatomical structure changes were analyzed. [Results] 1) The root system of C. dactylon after flooding decreased, and the growth of the aerial parts was inhibited. Most of the growth indexes were recovered to the level of land growth after 70 d of re-emergence. The stem diameter and plant height of M. alba decreased after 70 d of re-emergence, and there was still difference compared to the control. 2) There was no difference in the ratio of chlorophyll a/b between C. dactylon and the CK after 70 d of re-emergence, and the ratio of M. alba was 2.07 at the same time, which was still different from the CK. 3) The recovery rate of osmoregulation substance from roots of C. dactylon to the CK was faster than that of leaves, and there was no difference after 70 d of re-emergence. Some indexes from roots of M. alba in the same period did not restore to the normal level. 4) SOD and CAT of new leaves of C. dactylon and M. alba decreased gradually after re-emergence, and there was no significant difference between them after re-emergence of 70 d. The recovery rate of antioxidant enzyme and TTC content in C. dactylon root was faster than that of M. alba. 5) Most of the cells in the roots and stems of C. dactylon had become larger after submergence, and irregular atmospheric cavity fusion occurred. The structure of the roots was restored to the CK after 70 d of re-emergence. Some of the cells in the cortex of M. alba roots were dissociated, and the number of vessel cells significantly increased. After 70 d of re-emergence, there was still significant difference between the roots of flooded gorup and the CK of M. alba. [Conculsions] The structure and physiological indexes of roots and stems of C. dactylon actively are started the compensation effect quickly after re-emergence, while the M. albais has a slow start compensation mechanism, which is also a reason that the adaptability range of M. alba is narrower than C. dactylon.
甘丽萍, 杨玲, 李豪, 李欣, 任立. 三峡库区消落带狗牙根与桑树淹没后的恢复机制[J]. 中国水土保持科学, 2020, 18(5): 60-68.
GAN Liping, YANG Ling, LI Hao, LI Xin, REN Li. Recovery mechanism of Cynodon dactylon and Morus alba after re-emergence in the water-level-fluctuating zone of the Three Gorges Reservoir. SSWC, 2020, 18(5): 60-68.
苏维词,杨华,赵纯勇,等.三峡库区(重庆段)涨落带土地资源的开发利用模式初探[J].自然资源学报,2005,20(3):326. SU Weici,YANG Hua,ZHAO Chunyong,et al. A preliminary study on land exploitation and utilization models of water-level-fluctuating zone (WLFZ) in the Three Gorges Reservoir Area of Chongqing[J]. Journal of Natural Resources,2005,20(3):326.
[2]
鲍玉海,贺秀斌.三峡水库消落带土壤侵蚀问题初步探讨[J].水土保持研究,2012,18(6):190. BAO Yuhai,HE Xiubin. Preliminary study on soil erosion at the water-level-fluctuating zone of the Three-Gorges Reservoir[J]. Research of Soil and Water Conservation,2012,18(6):190.
[3]
郭燕,杨邵,沈雅飞,等.三峡库区消落带现存草本植物组成与生态位[J].应用生态学报,2018,29(11):3559. GUO Yang,YANG Shao,SHEN Yafei,et al. Composition and niche of the existing herbaceous plants in the water-level-fluctuating zone of the Three Gorges Reservoir Area, China[J]. Chinese Journal of Applied Ecology,2018,29(11):3559.
[4]
裴顺祥,洪明,郭泉水,等.三峡库区消落带水淹结束后狗牙根的光合生理生态特性[J].生态学杂志,2014,33(12):3222. PEI Shunxiang,HONG Ming,GUO Quanshui,et al. Photosynthetic characteristics of Cynodon dactylon in hydro-fluctuation belt of Three Gorges Reservoir at the end of flooding[J]. Chinese Journal of Ecology 2014, 33(12):3222.
[5]
黄先智,沈以红,蒋贵兵,等.三峡库区消落带桑树种植及资源利用调查[J].蚕业科学,2013,39(6):1193. HUANG Xianzhi,SHEN Yihong,JIANG Guibing,et al. An investigation on mulberry cultivation and resource utilization on water-fluctuation belt of the Three Gorges Reservoir[J].Science of Sericulture,2013,39(6):1193.
[6]
LI X L,LI N,JIN Y,et al. Morphological and photosynthetic responses of riparian plant Distylium chinensese seedlings to simulated autumn and winter flooding in Three Gorges Reservoir Region of the Yangtze River,China[J]. Acta Ecologica Sinica,2011,31(1):31.
[7]
李兆佳,熊高明,邓龙强,等.狗牙根与牛鞭草在三峡库区消落带水淹结束后的抗氧化酶活力[J].生态学报,2013,33(11):3362. LI Zhaojia, XIONG Gaoming,DENG Longqiang,et al. Dynamics of antioxidant enzyme activities in roots of Cynodon dactylon and Hemarthria altissima recovering from annual flooding[J]. Acta Ecologica Sinica, 2013,33(11):3362.
[8]
樊大勇,熊高明,张爱英,等.三峡库区水位调度对消落带生态修复中物种筛选实践的影响[J].植物生态学报,2015,39(4):416. FAN Dayong, XIONG Gaoming, ZHANG Aiying,et al. Effect of water-lever regulation on species selection for ecological restoration practice in the water-level fluctuation zone of Three Gorges Reservoir[J]. Chinese Journal of Plant Ecology,2015, 39(4):416.
[9]
袁贵琼.引种植物水桦对三峡库区消落带的适应性及安全性初探[D].重庆:西南大学,2018:22. YUAN Guiqiong. Study on the suitability and safety of Betulan nigra in the hydro-fluctuation zone of the Three Gorges Reservoir Area[D]. Chongqing:Southwest University,2018:22.
[10]
GRACE S C, LOGAN B A. Acclimation of foliar antioxidant systems to growth irradiance in three broad-leaved evergreen species[J]. Plant Physiol, 1996,112(4):1631.
NAKANO Y, ASADA K. Hydrogen peroxide is scavenged by ascorbate-specific peroxidase in spinach chloroplasts[J]. Plant Cell Physiology, 1981, 22(5):867.
[13]
李和平.植物显微技术[M].北京:科学出版社,2009:78. LI Heping. Plant microscopy[M]. Beijing:Science Press, 2009:78.
[14]
李娅,曾波,叶小齐,等.水淹对三峡库区岸生植物秋华柳存活和恢复生长的影响[J].生态学报,2008,28(5):1923. LI Ya,ZENG Bo,YE Xiaoqi,et al. The effects of flooding on survival and recovery growth of the riparian plant Salix variegata Franch. in Three Gorges Reservoir Region[J]. Acta Ecologica Sinica,2008,28(5):1923.
[15]
李佳杏,黄小辉,刘芸,等.模拟三峡库区消落带土壤水分条件下的桑树幼苗生长状况[J].蚕业科学,2012,38(2):210. LI Jiaxing,HUANG Xiaohui,LIU Yun,et al. Mulberry seedling growth under virtual soil moisture condition in hydro-fluctuation belt of the Three Gorges Reservoir Area[J]. Science of Sericulture,2012,38(2):210.
[16]
董馥慧,裴红宾,张永清,等.干旱胁迫与复水对苦荞生长及叶片内源激素含量的影响[J].中国农业科技导报,2019,21(12):41. DONG Fuhui,PEI Hongbin,ZHANG Yongqing,et al. Effect of drought stress and rehydration on growth and content of endogenous hormone in leaves of Fagopyrum tataricum[J]. Journal of Agricultural Science and Technology,2019, 21(12):41.
[17]
刘泽彬.三峡库区消落带两种植物对淹水环境适应性的模拟研究[D].北京:中国农业科学研究院,2014:71. LIU Zebin. A simulation study on the adaptability of two plants in hydro-fluctuation belt of Three Gorges Reservoir Region to flooding[D]. Beijing:China Academy of Agricultural Sciences,2014:71.
[18]
汤章城.逆境条件下植物脯氨酸的累积及其可能的意义[J].植物生理学通讯,1984(1):l5. TANG Zhangcheng. Accumulation of plant proline under adverse conditions and its possible significance[J]. Plant Physiology Communications,1984(1):15.
[19]
潘澜,薛晔,薛立.植物淹水胁迫形态学研究进展[J].中国农学通报,2011,27(7):11. PAN Lan,XUE Ye,XUE Li. Morphological research progress of plant flooding stress[J]. China Agronomy Bulletin, 2011, 27 (7):11.