KMS XINJIANG INSTITUTE OF ECOLOGY AND GEOGRAPHY,CAS
漫溢对荒漠河岸林恢复的影响及生态轮灌制度 | |
张沛 | |
Subtype | 硕士 |
Thesis Advisor | 徐海量 |
2016 | |
Degree Grantor | 中国科学院大学 |
Place of Conferral | 北京 |
Degree Discipline | 生态学 |
Keyword | 漫溢 荒漠河岸林 植被恢复 生态轮灌 |
Abstract | 作为生态恢复研究的一个重要分支,洪水漫溢干扰能够促进植物的种子的萌发,提高群落的物种多样性,提升群落的稳定性。然而在塔里木河这一典型干旱区内陆河流域,生态用水量少是导致塔里木河流域生态环境脆弱的主要因素,如何利用这有限的生态用水来实现洪水漫溢促进植被的恢复这一问题尚不清楚。基于此,本论文以塔里木河下游生态输水工程的实施为契机,以生态水文过程的基本理论和方法为指导,借鉴国内外在洪水漫溢过程中对植被特征研究的最新理论和方法,选择河水漫溢对荒漠河岸林植被生态恢复的作用为主要研究内容,调查荒漠河岸林植被群落演替对不同漫溢干扰下的响应差异,探讨漫溢对干旱区荒漠河岸林植被恢复的响应机理,研究主要建群植物恢复和保护的适宜漫溢干扰方式及地下水埋深,制定生态轮灌制度,为塔里木河下游的综合治理工程提供理论依据和技术支撑。本研究得出以下结论: (1) 河水漫溢能够增加植物群落的多样性,研究表明,漫溢方式为“每年漫溢1~2次,每次持续10~30天,放水速度25~30m³/s”的情况下植被群落的Shannon-Weiner指数和Margalef指数的值较大,相比于非漫溢区,Shannon-Weiner指数和Margalef指数分别高出79.15%和112.20%。为恢复胡杨林群落,适宜的漫溢方式为每年漫溢1~2次,每次持续10~30天,放水速度25~30m³/s。 (2) 荒漠河岸胡杨林的树轮宽度指数随地下水埋深的增加而减小,二者间存在显著的相关关系。胡杨幼林、近熟林、成熟林和过熟林的胁迫地下水埋深为4.0m、5~5.4m、6.9m和7.8m。为防止荒漠河岸胡杨林衰败,地下水埋深应小于不同龄级胡杨的胁迫水位。 (3) 制定生态轮灌制定所依据的原则为:在恢复乔灌木(胡杨和柽柳为主)时,给水时间应该在7~9月,恢复草本植物时给水时间以4~5月更合适。维系干流生物多样性稳定最佳的漫溢频次是1~2次/年,漫溢持续的时间以20~30天最佳。从胡杨成林的保护角度讲,最大输水间隔可以为3~5年;从恢复胡杨幼苗和促进胡杨种子繁衍的角度讲,最大过水间隔应不超过2年。 (4) 根据塔里木河植被分布及生态需水特点及恢复机理,制定的生态轮灌制度为:距离河道3km以内区域的植被可以通过河道渗漏补给生态用水,无需轮灌;3~20km区域内长势较好的天然植被5年实施轮灌2~4次,地下水埋深较低并且植被发育较差的区段,建议5年内实施轮灌3~5次;20km以外天然植被区由于引水条件较差,建议5年实现轮灌1~2次。 |
Other Abstract | As one of the important ways for ecological restoration, flooding disturbance could promoted seed germination, maintain high biodiversity and strengthen the stability of plant community. In Tarim River basin, the lack of ecological water is the key limiting factor for eco-environment, and it is not clear that how to utilize the finite ecological water to accomplish flooding which leads to restoring of vegetation. Therefore, based on the fundamental theories and methods, with the opportunity of Ecological Water Conveyance Project (EWCP) conducting in Tarim River, this research sets the impact of flooding disturbance on restoration of desert riparian Populus euphratica forest as the main contents, investigates the response and mechanism of vegetation community succession to different flooding disturbance, studies the suitable flooding disturbance mode and groundwater depth for restoration and protection of main constructive species and makes an eco-rotation flow system, for the purpose of providing theoretical basis and technical support for the comprehensive management of Tarim River basin. The main conclusions are stated as follows: (1)Flooding disturbance can increase the bio-diversity of plants community. This research shows that Shannon-Weiner index and Margalef index are relatively high under the flooding disturbance mode of “once or twice annually, ten to thirty days every time, speed 25~30 m³/s”, and compared to the non-flooding area, Shannon-Weiner index and Margalef index surpass by 79.15% and 112.20% separately. Fortunately, the suitable flooding disturbance mode for restoration of desert riparian forest is “once or twice annually, ten to thirty days every time, speed 25~30 m³/s”, too. (2)The tree-ring width index for P. euphratica significantly declines as the groundwater depth increases. The needing minimum groundwater depths of P. euphratica for young trees, near-mature trees, mature trees and over-mature trees are 4.0 m, 5.0~5.4m, 6.9 m and 7.8 m, respectively. In order to protect the desert riparian forest, the actual groundwater depth should be higher than the minimum groundwater depth for each tree growth stage. (3)The principles of developing eco-rotation flow system are: the flooding period should be during July to September for the purpose of restoring trees and shrubs, while, to restore the herbs, the flooding period should be April and May; the suitable flooding disturbance frequency is twice or three times annually for maintaining the high level of bio-diversity, with 20 to 30 days every time; to accelerate the germination of P. euphratica seeds and meet the water requirement of seedlings, the max interval of flooding is two years, whereas, from the point of P. euphratica forest conservation, the max interval could be prolonged to 3~5 years. (4)According to the distribution and water requirement mechanism of vegetation in both bank of Tarim River, the eco-rotation flow system is: vegetation distributed within the range of 3 km from the riverway is supported by riverbed leakage, irrigation is not necessary; vegetation in the range of 3 to 20 km from the riverway should be irrigated twice to four times every five years, however, the area where vegetation grow worse and groundwater is deeper should be irrigated three to five times every five years; vegetation distributed beyond the range of 20 km from the riverway should be irrigated once or twice every five years for the lack of water drawn projects. |
Subject Area | 生态学 |
Language | 中文 |
Document Type | 学位论文 |
Identifier | http://ir.xjlas.org/handle/365004/14721 |
Collection | 研究系统_荒漠环境研究室 |
Affiliation | 中科院新疆生态与地理研究所 |
Recommended Citation GB/T 7714 | 张沛. 漫溢对荒漠河岸林恢复的影响及生态轮灌制度[D]. 北京. 中国科学院大学,2016. |
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