摘要
为了解决滨海土壤盐碱度高导致的景观萧条问题,利用限氧热解技术制备浒苔生物炭及利用H3PO4改性浒苔生物炭,研究生物炭在盐碱土浸提液、非盐碱土和盐碱土中对Na+的吸附迁移机制。结果表明,生物炭对Na+的吸附符合Langmuir吸附模型和准二级动力学方程。10%H3PO4(v/v)改性的生物炭(A2)对Na+的吸附率最大,吸附容量最大为10.03 mg/g,是原始生物炭的2倍。添加5%(w/w)A2可使盐碱土的pH值由7.90~7.98降低至7.21~7.29。生物炭的添加减少了盐分随水分的上移,在植物根区形成相对的低Na+、低pH区,有利于缓解盐碱对植物的胁迫。H3PO4改性后的生物炭增加了比表面积、羧基和羟基等含氧官能团,同时,H+取代了与-COO-结合的大量金属阳离子,然后被盐碱土的碱性成分消耗,空出的位点又与Na+结合,降低了土壤盐碱度。故H3PO4改性浒苔生物炭有利于改良滨海盐碱土,提高植被的覆盖率。
To solve the problem of landscape depression caused by high salinity and alkalinity of coastal soil,the method of limiting oxygen pyrolysis was used to prepare Enteromorpha prolifera biochar and H3PO4 was used to modify Enteromorpha prolifera biochar.The mechanism of adsorption and migration of Na+in saline-alkaline soil water extract,non-saline-alkaline soil and saline-alkaline soil was studied.The results show that the adsorption of Na+by biochar conforms to the Langmuir adsorption model and the quasi-second-order kinetic equation.The 10%H3PO4(v/v)modified biochar(A2)had the highest adsorption rate of Na+,and the maximum adsorption capacity was 10.03 mg/g,which was twice that of the original biochar.The addition of 5%(w/w)A2 reduced the pH of the saline-alkali soil from 7.90~7.98 to 7.21~7.29.The addition of biochar reduced the upward movement of salt with water,and formed a relatively low Na+and low pH region in the root zone of the plant,which was beneficial to alleviate the stress of the saline-alkali on plants.The biochar modified by H3PO4 increased specific surface area and the oxygen content functional groups such as carboxyl group and hydroxyl group.At the same time,H+replaced a large amount of metal cations bound to-COO-,and was then consumed by the alkaline components of the saline-alkaline soil.The vacated site was combined with Na+,which reduced soil salinity.Therefore,H3PO4 modified Enteromorpha prolifera biochar is beneficial to improve coastal saline-alkali soil and improve vegetation coverage.
作者
陈友媛
王翔宇
吴海霞
孙萍
吴丹
CHEN You-Yuan;WANG Xiang-Yu;WU Hai-Xia;SUN Ping;WU Dan(College of Enviromontal Science and Engineering.Ocean University of China,Qingdao 266100,China;Key Lab of Manine Environmental Science and Ecology,Ministry of Education,Ocean University of China,Qingdao 266100,China;Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of China,Qingdao 266100,China)
出处
《中国海洋大学学报（自然科学版）》
CAS
CSCD
北大核心
2019年第S1期85-92,共8页
Periodical of Ocean University of China
基金
山东省重点研发计划项目(2017GSF17119)
山东省自然科学基金项目(ZR2019MD033)资助~~
关键词
浒苔生物炭
磷酸改性
盐碱土
吸附
淋滤
钠离子
Enteromorpha prolifera biochar
phosphoric acid modification
saline-alkaline soil
adsorption
leaching
sodium ion
