磷矿粉和水稻秸轩对土壤铅污染钝化和作物生长的影响

发布时间：2017-12-27 20:14

本文关键词：磷矿粉和水稻秸轩对土壤铅污染钝化和作物生长的影响　出处：《华中农业大学》2015年硕士论文　论文类型：学位论文

【摘要】：农田土壤中重金属污染对生态环境质量、食品安全和社会经济持续发展构成严重威胁,已成为环境污染控制的重点与难点,是当前亟待解决的突出环境问题。本文利用磷矿粉(含活化磷矿粉)与经过一定腐化处理的水稻秸秆混合施于铅污染土壤,开展盆栽试验和室内培养试验,研究供试材料对铅的钝化效果和对土壤基本性质的影响,同时利用磷矿粉在湖南省临湘市忠防镇桃林铅锌矿区进行田间试验,钝化土壤重金属。主要研究结果如下:1、施用磷矿粉能提高小白菜叶片叶绿素值和生物量,降低小白菜铅含量和生物积累量。盆栽试验中,施用含磷(P2O5)0.12 g/kg活化磷矿粉能提高小白菜叶绿素值,与对照相比增幅达33%以上,而同量原磷矿粉能提高10%;对照处理中,45天生长的生物量仅为1.48 g/株,施用磷矿粉和活化磷矿粉处理,小白菜生物量分别可达2 g/株和3 g/株以上,而高量活化磷矿粉处理小白菜生物量超过5 g/株;对照处理中小白菜铅浓度高达17.18 mg/kg,铅累积量为25.3 ug/株,低量和高量活化磷矿粉降低小白菜铅浓度到4.96 mg/kg和2.78 mg/kg,铅积累量减少了25%和37%。2、添加磷矿粉和腐熟水稻秸秆都可显著提高土壤p H、有效磷、交换性钙含量和阳离子交换量,与施用量呈正相关,且活化磷矿粉效果强于原磷矿粉。盆栽试验中添加磷矿粉和水稻秸秆可使土壤p H提高0.48,土壤有效磷、交换性钙含量提高1.06-8.21 mg/kg和0.14-0.49 cmol/kg,阳离子交换量增加0.23-1.81 cmol/kg。而培养试验中添加磷矿粉和腐熟水稻秸秆可使土壤p H提高0.28,淹水处理的土壤p H比保持70%田间持水量处理的土壤p H值高,平均差值0.14;可使土壤有效磷含量提高0.11-9.16 mg/kg,添加了腐熟水稻秸秆的处理土壤有效磷含量比未添加的平均增加0.36 mg/kg,淹水处理含量比保持70%田间持水量处理的低0.3-1.5 mg/kg;交换性钙含量提高0.04-0.72 cmol/kg,添加了腐熟水稻秸秆的处理比未添加的略高,但差异不显著,高量原磷矿粉比低量原磷矿粉处理的土壤交换性钙含量增加了0.18cmol/kg,淹水处理比保持70%田间持水量处理的土壤高0.22-0.47 cmol/kg,添加磷矿粉和腐熟水稻秸秆可使土壤阳离子交换量提高0.12-1.44 cmol/kg。3、添加磷矿粉和腐熟水稻秸秆可使土壤各形态铅含量发生显著变化,减少交换态铅含量,增加铁锰氧化物结合态、残渣态等含量。盆栽试验中各处理与对照相比,可降低交换态铅35 mg/kg,降幅28.7%;培养试验中添加磷矿粉和腐熟水稻秸秆使交换态铅降低4.5-50.8 mg/kg,最多比对照降低40.3%。培养试验中添加腐熟水稻秸秆的处理交换态铅浓度比未添加的低4.8-13.2 mg/kg,淹水处理比保持70%田间持水量处理低4.6-17.4 mg/kg。添加腐熟水稻秸秆的处理有机结合态铅浓度比未添加的处理高6.6-10.2 mg/kg;淹水处理的土壤铁锰氧化物结合态比保持70%田间持水量的处理高,最大差值可达14.7 mg/kg,各处理中碳酸盐结合态铅差异不显著。4、施用磷矿粉和活化磷矿粉能提高土壤p H值、钝化重金属、降低农作物重金属含量、促进农作物增产。水稻土经一季种植后p H值约增加0.22,两季种植后可再提高0.10。水稻田中施用活化磷矿粉,油菜收获后土壤交换态铅降低到25.3mg/kg,降幅为35%;土壤有效态锌降低到45.2 mg/kg,降幅为39%。活化磷矿粉可使油菜籽中铅、锌浓度降低43%和24%;活化磷矿粉处理产量与对照相比增产234 kg/ha,增产率为16%。水稻收获后,施用活化磷矿粉能持续降低土壤交换态铅,降幅增加19%;有效态锌减少6.4 mg/kg。活化磷矿粉可使稻谷中铅和锌浓度分别降低40%和27%;活化磷矿粉处理水稻产量与对照相比增产604 kg/ha,增产率为7%。综上可知,活化磷矿粉施于土壤能促进铅的钝化,且比未活化磷矿粉的钝化效果显著;磷矿粉与腐熟秸秆混施能显著提高钝化效果,而未腐熟的秸秆混施没有明显效果;施用钝化剂后进行淹水处理能显著提高钝化效果。本文分析了不同钝化材料在不同条件下对铅的钝化效果,并对实验进行了深入讨论,为铅污染土壤治理提供了一定理论依据,但对于不同材料之间的相互作用,以及不同条件下与铅的交互作用机理,仍需进一步研究。
[Abstract]:Heavy metal pollution in farmland soil is a serious threat to the quality of ecological environment, food safety and sustainable development of society and economy. It has become the focus and difficulty of environmental pollution control, and it is the outstanding environmental problem to be solved at present. This paper uses phosphorite powder (containing activated phosphate rocks) and rice straw mixed decay after a certain processing applied to lead contaminated soil in pot experiment and indoor incubation experiment, the research tested the passivation effect of materials on the lead and influence on soil basic properties, and the use of phosphate rock powder field test was carried out in Linxiang City, Hunan province Zhong Fang the town of Taolin lead-zinc mine, passivation of heavy metals in soil. The main results are as follows: 1. The application of phosphate mineral powder can improve the chlorophyll value and biomass of Chinese cabbage leaves, and reduce the content of lead and biological accumulation in Chinese cabbage. In the pot experiment, the application of phosphorus (P2O5) 0.12 g/kg activated phosphate rocks can improve chlorophyll value, compared with an increase of over 33%, while the amount of raw phosphate can increase 10%; control treatment, 45 days of biomass growth is only 1.48 g/ strains, applying phosphate and activated phosphorite powder, small the cabbage biomass was up to 2 g/ strains and 3 g/ strains, and the high amount of activated phosphate rock processing of Pakchoi biomass is more than 5 g/ strains; small cabbage lead concentration up to 17.18 mg/kg control, the lead accumulation was 25.3 ug/ strain, low volume and high amount of activated phosphorite powder reduced concentration of lead to Chinese cabbage 4.96 mg/kg and 2.78 mg/kg, the lead accumulation decreased 25% and 37%. 2, adding phosphorus ore powder and decomposing rice straw can significantly improve soil P H, available phosphorus, exchangeable calcium content and cation exchange volume, and positively correlated with the amount of application, and the effect of activated phosphate ore is stronger than that of raw phosphate rock. In pot experiment, adding phosphorus ore powder and rice straw can increase soil P H by 0.48, increase soil available phosphorus and exchangeable calcium content 1.06-8.21 mg/kg and 0.14-0.49 cmol/kg, and increase cation exchange capacity 0.23-1.81 cmol/kg. And add to the culture of phosphorus ore and decomposition of rice straw in the soil test p H increased by 0.28, flooding the soil P H water treatment maintained more than 70% of field capacity of soil P H value is high, the average value of 0.14; the soil available phosphorus content increased 0.11-9.16 mg/kg, adding the treatment of soil available phosphorus content in rice straw compost the ratio did not add an average increase of 0.36 mg/kg, the content of water treatment water treatment maintained more than 70% of field capacity low 0.3-1.5 mg/kg; exchangeable calcium content increased 0.04-0.72 cmol/kg, adding the treatment of decomposition of rice straw is slightly higher than without, but the difference is not significant, high Liangyuan phosphaterock than the low amount of raw phosphate ore processing exchangeable calcium content in soil increased 0.18cmol/kg, waterlogging water treatment maintained more than 70% of field capacity of soil with high 0.22-0.47 cmol/kg, adding phosphorus ore and decomposition of rice straw in the soil cation exchange capacity increased by 0. 12-1.44 cmol/kg. 3, adding phosphorus ore powder and decomposing rice straw can significantly change the lead content in different forms of soil, reduce the content of exchangeable lead, increase the content of iron manganese oxide bound state, residue state and so on. In the pot experiment, compared with the control, each treatment could reduce the exchange lead 35 mg/kg and decrease 28.7%. In the culture experiment, the addition of phosphate ore and cooked rice straw reduced the exchangeable lead by 4.5-50.8 mg/kg, which was 40.3% lower than that of the control. In the culture experiment, the concentration of exchangeable lead increased with the addition of rotten rice straw. The concentration of lead in the exchangeable lead was lower than that in the 4.8-13.2 mg/kg which was not added. The treatment of waterlogging was lower than that of the 70% field water holding capacity, which was 4.6-17.4 mg/kg. The organic combination of Pb concentration 6.6-10.2 mg/kg higher than the treatment without adding decomposition of rice straw; treatment of flooded soil iron manganese oxide bound processing maintained more than 70% of field capacity is high, the maximum difference was 14.7 mg/kg, the carbonate bound Pb had no significant difference. 4. The application of phosphate mineral powder and activated phosphorus mineral powder can increase the P H value of soil, passivate heavy metals, reduce the content of heavy metals in crops, and promote the increase of crop yield. After one season, the P H value of paddy soil increased by 0.22, and then increased by 0.10 after planting in the two season. After application of activated phosphate ore in paddy field, the soil exchangeable lead decreased to 25.3mg/kg, the decline was 35%, and the available zinc in soil decreased to 45.2 mg/kg, and the decline was 39%. Activated phosphate ore can reduce the concentration of lead and zinc in Rapeseed by 43% and 24%, and the yield of activated phosphorus mineral powder increases by 234 kg/ha compared with the control, and the yield increase is 16%. After the harvest of rice, the application of activated phosphorus mineral powder can continue to reduce the exchangeable lead in the soil, the decrease increase by 19%, and the decrease of 6.4 mg/kg in the effective state zinc. Activated phosphate ore can reduce the concentration of lead and zinc in Rice by 40% and 27%, and the yield of rice by activated phosphorus mineral powder is 604 kg/ha compared with the control, and the yield increase is 7%. In summary, the passivation of activated phosphorite powder applied to soil can promote the lead, and not the passivation effect of activated phosphorite powder significantly; phosphate rock and rotten straw mixed fertilizer can significantly improve the passivation effect, while raw straw mixed fertilizer had no obvious effect; application of passivator after waterlogging treatment can significantly improve the passivation effect. This paper analyzes the effect of different materials on the passivation passivation of lead in different conditions, and the experiment is discussed deeply, provide some theoretical basis for soil lead pollution governance, but for the interaction between different materials, and the interaction of different conditions and mechanism of lead, still need further study.
【学位授予单位】：华中农业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X53

【参考文献】