Abstract

Wastewater used as irrigation water is causing heavy metal accumulation in the agro-ecosystems. A greenhouse study was conducted to compare the phytoaccumulation ability of four agroforestry tree species under different wastewater treatments. Three-month-old potted seedlings of Morus alba, Acacia nilotica, Acacia ampliceps, and Azadirachta indica were irrigation with tap water (C), municipal wastewater (MWW), and industrial wastewater (IWW). Results showed that MWW had a positive and IWW had a negative impact on biomass production in all the species. Acacia ampliceps showed the highest increment (65%) and showed the lowest decrease (5%) in total biomass under both MWW and IWW treatment. Pb concentration was also found highest in the leaves, stem and roots of Azadirachta indica (108.5, 46.2, 180.5 mg kg⁻¹, respectively) under IWW. Production of H₂O₂ was highest in IWW treatment with almost 148% increase observed in Azadirachta indica. Similarly, the production of antioxidative enzymes (Superoxide dismutase, Catalase and Peroxidase) was also highest in Azadirachta indica under IWW. Therefore, results suggest that along with high increment in total biomass, both Acacia ampliceps and Azadirachta indica showed high Pb concentration and an effective antioxidative defense mechanism and thus, can be used for planting in soils irrigated with MWW and IWW.

摘要

用作灌溉用水的废水正在农业生态系统中引起重金属积累。进行了温室研究，以比较四种农林树木在不同废水处理下的植物累积能力。用自来水（C），市政废水（MWW）和工业废水（IWW）灌溉桑树（Morus alba），尼古拉相思树（Acacia nilotica），相思树（Acacia ampliceps）和印度印Three（Azadirachta indica）三个月大的盆栽幼苗。结果表明，MWW对所有物种的生物量生产均具有积极影响，而IWW则具有负面影响。阿拉伯相思在MWW和IWW处理下，总生物量的增幅最高（65％），降幅最低（5％）。铅浓度还发现在叶最高，茎和根印楝（108.5，46.2，180.5毫克千克^-1，分别地）IWW下。在IWW处理中，H ₂ O _2的产量最高，在印度的印za中观察到几乎增加了148％。同样，在IWW下，印za （Azadirachta indica）中抗氧化酶（超氧化物歧化酶，过氧化氢酶和过氧化物酶）的产量也最高。因此，研究结果表明，在总生物量高增量以来，这两相思ampliceps和印楝 由于Pb具有较高的Pb浓度和有效的抗氧化防御机制，因此可用于在MWW和IWW灌溉的土壤中种植。