水量衡算条件下人工湿地对有机物的去除

构建了芦苇和无植物人工湿地，在系统水量衡算的基础上比较了两种湿地对生活污水中有机物的去除效果。结果表明，在植物收割后的冬季，有植物湿地对有机物的去除率低于无植物湿地2.2%；在其他季节，芦苇湿地对污水CODCr的去除率比无植物的高出3.2%～4.2%，但对BOD5的去除率却比无植物的低了1.8%～3.4%。有植物湿地对有机物的去除效果比无植物湿地有所改善，但是提高不多。比较了两种系统的氧化还原电位，有植物湿地比无植物湿地高（P<0.05），这种提高主要集中在湿地水面以下约15 cm的范围，从整体来看，两块湿地内部氧化还原状态大体相同，主要是强还原环境。比较了两块湿地基质中降解有机物的细菌、放线菌和真菌的数量，二者没有明显的差别，但是，有植物湿地的根际效应明显。考察了湿地进水有机负荷与去除量的关系，二者呈现显著的线性相关性(R2>0.96)。 

COMPARISON OF ORGANIC MATTER REMOVAL IN SUBSURFACE HORIZONTAL-FLOW WETLANDS BASED ON WATER BUDGET

Planted with Phragmites australis and unplanted wetlands were constructed to compare organic matter removal from domestic wastewater based on water budget. Planted wetland had a removal rate of organic matter 2.2% lower than unplanted wetland in winter with plant harvested. In other seasons, the removal rate of CODCr in planted wetland was 3.2%～4.2% higher than that in unplanted wetland, while BOD\-5 was 1.8%～4.8% lower than that in unplanted wetland. Consequently, planted wetland showed a little well overall performance than unplanted, but the improvement was not obvious. Comparisons of paired systems commonly showed a little higher oxidation reduced potential (ORP) than unplanted wetland; however, the increase mainly concentrated on the range of top 15 cm water. From the overall bed, ORP is mostly similar for both wetlands with anaerobic condition. Bacteria, actinomice and fungi in wetlands substrate were monitored, and there was little difference between planted and unplanted wetlands. However, rhizosphere effect of reed was strong. Organic matter loading rate and removal rate showed obviously strong linear relationships (R2>0.96).