湖泊科学2018，Vol.30Issue(1)：15-24,10.DOI:10.18307/2018.0102
我国南方桉树(Eucalyptus)人工林区水库突发性泛黑形成机理初探
Mechanism of "black-water" occurrence in the reservoirs with Eucalyptus plantation,southern China
摘要
Abstract
Eucalyptus can grow into wood in two or three years and has large-scale cultivation in the southern China,with high economic value.Recently it is considered "pump","green desert",and even rumoured "toxic." The water in the reservoir in Eucalyptus planting area appeared "black" sporadically.The water was dark brown with a pungent smell,which has caused great panic within local residents.The phenomenon is associated to Eucalyptus trees plantation.To explore the mechanism of "blackwater" in the reservoir in Eucalyptus plantation,southern China,three typical reservoirs (Najiang,Tianbao,Baihe Reservoirs) were selected in Eucalyptus planting area.Main water quality variables including hydrological and environmental factors were observed 4 times,from August 2015 to April 2016.The physicochemical indexes of water were determined,and then synthetic analysis was performed combined with hydrological data provided by the Nanning Metrological Station.The results indicate that reservoirs in Eucalyptus forest area blackening are associated with a particular season and special climatic conditions.Meanwhile,the instability of water temperature stratification structure is the main driving factor of black materials transport.In summer,hierarchical structure,the water temperature in reservoirs keeping thermal stratification structure stable,results in dissolved oxygen and other water quality indexes were changing with stratification and limits transporting upward.In autumn and winter,stratification disappears,and vertical exchange of water body provides the underlying pollutants with upward force.Finally,pollutants spread the whole body and lead "blackwater" phenomenon.Seasonality and spatial heterogeneity of sulfide,tannic acid,iron,manganese and other materials is closely related to the seasonal characteristics of water temperature stratification.In the Eucalyptus forest reservoirs,iron and manganese concentrations are up to 2.93 and 3.46 mg/L,respectively.A large amount of tannic acid appeared when Eucalyptus leaves soaked in the water.When sulfide,tannic acid,iron and manganese exist together,a series of reactions such as iron,manganese and sulphur,sulphur and tannic acid,iron,manganese and tannic acid can produce black complex.Our results can provide guidance in guaranteeing the safety of drinking water sources in Eucalyptus planting area and lay the foundation for the further research of black water.关键词
桉树林/水库/温度分层/泛黑/单宁酸/饮用水安全/中国南方地区Key words
Eucalyptus forest/reservoir/thermal stratification/black water/tannic acid/safety of drinking water/southern China引用本文复制引用
李一平,罗凡,郭晋川,李荣辉,王芳,高广灿..我国南方桉树(Eucalyptus)人工林区水库突发性泛黑形成机理初探[J].湖泊科学,2018,30(1):15-24,10.基金项目
水利部公益性行业科研专项(201301044)和国家自然科学基金项目(51579071,51409050)联合资助. （201301044）
