AM真菌、土壤改良剂对松嫩平原沙化土壤的修复过程研究

The soil of western of songnen plain faces a serious sandy problem due to both the natural reasons and human irrational tillage and grazing,which restrict the development of this area.Many kinds of methods have been used for recovery of this sandy soil since 80s of 20th century,while not effective enough for containing the sandy trend.As soil is the fundation of the ecosystem, its structure,character and quality will effect the activity and function of soil fauna and flora,microorganisms directly. This study will focus on the underground of the ecosystem,beginning with the amendment of soil for the restoration of sandy ecosystem.4 species of songnen western plain native plants were chosed for the field work.Then measure the effect of the addition of AMF,biochar and compose on the stucture of the soil and primary production of the ecosystem. There are 2 groups of field work,one is plant plug experiment,the other is seed application experiment,and factorial design and fully-crossed design will be used respectively.The effects of the addition of different amendment and their blends on the soil structure(especially soil aggregation),soil water retention ability,soil fertility and primary production of ecosystm ect will be analyzed later. Based on the field work and the data about the effects,the synergism of AMF,biochar and compost will be found,and an economical & environmental sustainable pattern of the restoration of sandy soil in western songnen plain will be detected and established.

松嫩平原农牧交错带在人类不合理耕作及自然因子的双重作用下，土地普遍沙化，制约了当地经济社会和生态环境的有序发展。20世纪80年代以来虽开展了多种沙化土地治理的模式研究，但沙化趋势未得到有效扼制，土壤肥力逐年下降。本研究以沙化土壤结构的改良为主线，以当地原生的四种耐旱植物-（大针茅、羊草、沙打旺、苜蓿）为主要研究对象，通过野外移栽及播种两种实验手段；随机设计和正交实验设计的途径，分析AM真菌菌剂、生物炭和有机肥单独及混合添加对土壤结构（土壤团聚体）、土壤理化性质、土壤肥力、菌根共生体系的建立以及植物群落多样性的综合影响，揭示AMF菌剂、生物炭、有机肥施加对沙化土壤改良的作用过程，寻求沙化土壤长效的、经济的生物改良技术。

以沙化土壤系统的改良和利用为主线，设计室内控制实验和大田实验，测定土壤碳改良剂的施加对牧草生长和作物产量的影响，以及退化沙化土壤性质的恢复过程。重点揭示人为施加改良剂后对退化生态系统的恢复进程影响，以及植物生产力，作物产量的响应。实验结果表明人为施加改良剂后，沙化土壤的理化性质得到不同程度的改善，土壤持水量，土壤有机碳、碳氮比，土壤团聚体稳定性，土壤速效氮磷钾含量和阳离子交换量比对照有所增加，土壤容重和比重降低。生物炭和有机肥的施加对作物产量、植物叶片叶绿素含量、植株生物量以及土壤微生物类群含量的增加效应显著，但对AM真菌的侵染未体现出显著效应。同时结果表明二者联合施加的效果均优于单独施加，而且即使少量生物炭与有机肥进行混合施加后其效应也显著优于单独施加，体现出了不同改良剂的协同作用。