不同水质灌溉对毛红椿生长及基质性质的影响

Influence of irrigation by different quality water on properties of culture matrix and growth of Toona ciliata var. pubescens

在全球水资源日益缺乏的情景下,伴随城市化过程出现的生活污水量显著增加,如何有效利用这一资源成为社会、经济可持续发展的关键。以珍贵树种毛红椿为材料,在遮雨棚下系统研究了生活污水、生活污水与自来水的混合水(以下简称"混合水")以及自来水为灌溉水质,对毛红椿播种苗生长、育苗基质的性质及其中主要重金属含量的影响,以探讨生活污水应用于育苗生产的可能性。结果表明:(1)生活污水与混合水灌溉后均促进了毛红椿苗高、地径的生长,苗高分别为自来水的213.1%、210.4%,地径分别为163.9%、155.5%,生物量的增加也非常明显,特别是地上部分生物量,不同水质间苗高、地径、生物量均达到显著性差异。(2)生活污水灌溉改善了栽培基质的pH、容重等性质,但重金属含量也出现增加的趋势,不过均低于《土壤环境质量标准》(GB15618—1995)中二级标准限值,同时毛红椿各器官中重金属含量也升高。不同重金属在不同器官中的富集程度不同,Cu、Zn、As、Mn在叶中富集较明显,Cr、Pb没有出现富集现象。因此,生活污水及混合水可应用于毛红椿苗木培育。

It was key to use sewage water sufficiently to achieve socio-economical sustainable development which increased dramatically with urbanization in the scenario of water shortage globally.Influence of irrigation by different quality water,i.e.sewage water,mixture water of sewage water and tap water and tap water on growth of seedlings,matrix properties and their heavy metal concentration were studied by one precious tree-Toona ciliata var.pubescens under shelter to value the possibility of usage of sewage water in seedlings culture.The results showed that：（1）growth of height and ground diameter of Toona ciliata var.pubescens were promoted when irrigated by sewage water and mixture water.Height of seedlings irrigated by sewage water were 213.1%to that irrigated by tap water,and height of seedlings irrigated by mixture water were 210.4%to that irrigated by tap water.Ground diameter of seedlings irrigated by sewage water were 163.9%to that irrigated by tap water,and ground diameter of seedlings irrigated by mixture water were 155.5% to that irrigated by tap water.Biomass,especially over ground biomass was more when irrigated by sewage water than when irrigated by tap water.Seedlings height,ground diameter and biomass were different significantly irrigated by different quality water.（2）pH and density of matrix were improved by irrigated sewage and mixture water.Heavy metal concentration of matrix irrigated by sewage water was higher than that irrigated by tap water too.However,the heavy metals were under the limiting value for culture soil according toⅡ class value of＂Standord of soil environmental quality＂（GB 15618-1995）.Meanwhile,heavy metal concentration in Toona ciliata var.pubescens irrigated by sewage water were higher than that irrigated by tap water.However,only the enrichment coefficient of Cu,Zn,As and Mn in leaf were greater than 1.Cr,Mn and Pb didn＇t accumulate in leaf,stem and root of seedlings.Sewage water,especially mixture water could be used in seedlings culture for its multiple benefits.