红树林种植-养殖耦合湿地生态修复效果评价

Evaluation of mangrove-aquaculture integrated system in wetland eco-restoration in Shenzhen

2014年08月以深圳海上田园红树林种植-养殖耦合系统为研究对象,从修复湿地的环境质量状况、生物群落结构及植物健康状况等方面,对3个不同修复年限(6,10和12a)样地的生态修复效果进行了定量评价.修复区水体和沉积物营养盐和重金属含量显著低于对照河道区,但各修复区池塘水质均未达到国家海水Ⅱ类水质标准,不能满足水产养殖用水要求;各修复区已修复红树林的生物群落结构,红树植物高度和胸径相比自然林修复比例低于35.5%,得分均处于"差"的等级;红树植物健康状况方面,叶片酶活含量和光合特征随修复年限呈现增大的趋势,但仍处于"差"的等级;6,10和12a修复样地综合评级得分为1.61、1.69和2.07,均为"中",表明修复工程并未对湿地退化生境带来显著恢复,仅适度改善了红树林植物的群落结构和健康状况.

Three wetland sites,restored for6,10and12years respectively,at Waterlands Resort in Shenzhen were designated for the evaluation of wetland eco-restoration.A comprehensive index system was built for quantitative assessments on the efficiency of restoration,including environmental factors,mangrove community structure and physiological status of mangrove plants.Concentrations of macronutrients and heavy metals in both water and sediment of restored areas had been effectively decreased,though still found to be under the acceptable values suggested by the aquaculture criteria.Although the community structure and physiological status of mangrove plant had been significantly improved with the increasing restoration duration,great discrepancies remained between the restored and the natural mangroves.The ecological restoration score for three sites are1.61,1.69and2.07,respectively.Their integrated restoration levels were all ranked as“Medium”,indicted that the full restoration for the retrogressive wetland ecosystem will require decades or longer time for development.