本文關鍵詞：凹凸棒添加堆肥過程中的重金屬形態(tài)變化與生物毒性研究　出處：《蘭州交通大學》2015年碩士論文　論文類型：學位論文

  更多相關文章： 凹凸棒 堆肥 重金屬 形態(tài)轉化 生物毒性

【摘要】：隨著我國規(guī)�；�、專業(yè)化、集約化養(yǎng)殖業(yè)的迅速發(fā)展,含有大量重金屬添加劑的飼料被廣泛應用,這導致禽畜糞便中重金屬元素嚴重超標。以此作為有機肥在農耕過程中長期施用,不僅會導致重金屬在土壤和植物中的累積,處理不當會造成嚴重的環(huán)境問題,危及人類健康。因此,研究重金屬形態(tài)在雞糞堆肥發(fā)酵過程中的動態(tài)變化規(guī)律,探明凹凸棒的鈍化機理,分析重金屬形態(tài)的生物毒性對指導畜禽養(yǎng)殖業(yè)廢棄物的資源化利用和凹凸棒在堆肥過程中的應用具有現實意義。本研究以采自甘肅省張掖市甘州區(qū)祥翔養(yǎng)殖農民專業(yè)合作社的雞糞和由甘肅雙泰凹土科技有限公司提供的凹凸棒為實驗材料。設定6個處理,分別在雞糞中添加不同比例的凹凸棒,進行好氧堆肥實驗。通過測定在雞糞堆肥發(fā)酵過程中,Cd、Cr、Cu、Ni和Zn五種重金屬在不同處理中各個取樣時間點(第1、4、12、20、25、32天)上的總量、BCR連續(xù)提取法的形態(tài)分布,以及分析各形態(tài)間不同重金屬的相關性、不同重金屬各形態(tài)與種子萌發(fā)特性的相關性,來研究凹凸棒添加堆肥發(fā)酵過程中的重金屬形態(tài)變化和生物毒性。實驗結果表明:(1)在凹凸棒添加的雞糞堆肥發(fā)酵過程中,堆肥32天腐熟后,各個處理中Cd、Cr、Cu、Ni和Zn的濃度均大于堆肥前,且隨著凹凸棒添加比例的增高,表現出更為顯著的相對濃縮效應。(2)在凹凸棒添加的雞糞堆肥發(fā)酵過程中,堆肥32天腐熟后,各個處理中重金屬Cd、Cr、Ni和Zn的形態(tài)變化均表現出由不穩(wěn)定形態(tài)向穩(wěn)定形態(tài)轉化的趨勢。重金屬Cu則表現出由不穩(wěn)定形態(tài)酸溶態(tài)和穩(wěn)定形態(tài)殘渣態(tài)向其它形態(tài)轉化的趨勢。各處理不同的配比方案,對雞糞堆肥發(fā)酵過程中重金屬的鈍化效果,因重金屬元素的不同而各異,A3(凹凸棒:雞糞為3:20)處理對重金屬Cd和Cr的鈍化效果最佳;A9(凹凸棒:雞糞為9:20)處理對重金屬Cu和Ni的鈍化效果最佳;A6(凹凸棒:雞糞為6:20)處理對重金屬Zn的鈍化效果最佳。(3)凹凸棒的添加對堆肥中重金屬的形態(tài)具有顯著影響。對酸溶態(tài)Cd、Cr、Cu、Ni和Zn而言,同一時間下,隨凹凸棒添加比例的增加其濃度逐漸降低;同一凹凸棒添加比例的處理中,其濃度隨時間的延長而降低。對還原態(tài)Cd、Cr、Cu、Ni和Zn而言,同一時間下,隨凹凸棒添加比例的增加其濃度逐漸降低。同一凹凸棒添加比例的處理中,還原態(tài)Cr濃度隨時間的延長而降低;還原態(tài)Cd、Cu、Ni和Zn濃度隨時間的延長而升高。對氧化態(tài)Cr、Cu、Ni和Zn而言,同一時間下,隨凹凸棒添加比例的增加其濃度逐漸降低;而氧化態(tài)Cd隨凹凸棒添加比例的增加其濃度逐漸升高。同一凹凸棒添加比例的處理中,氧化態(tài)Cd、Cr、Cu和Ni濃度隨時間的延長而升高;氧化態(tài)Zn濃度隨時間的延長而降低。對殘渣態(tài)Cd、Cr、Ni和Zn而言,同一時間下,隨凹凸棒添加比例的增加其濃度逐漸降低;同一凹凸棒添加比例的處理中,其濃度隨時間的延長而升高。對殘渣態(tài)Cu而言,同一時間下,隨凹凸棒添加比例的增加其濃度逐漸升高;同一凹凸棒添加比例的處理中,其濃度隨時間的延長而降低。說明凹凸棒在雞糞堆肥發(fā)酵過程中的添加,對重金屬穩(wěn)定形態(tài)濃度的升高和不穩(wěn)定形態(tài)濃度的降低具有促進作用;對重金屬穩(wěn)定形態(tài)濃度的降低和不穩(wěn)定形態(tài)濃度的升高具有抑制作用。(4)凹凸棒添加的雞糞堆肥發(fā)酵過程中,綜合六個處理,在不同的重金屬形態(tài)中各重金屬之間皆具有顯著相關性。(5)對植物種子而言,與重金屬形態(tài)變化的相關性排序依次為:白菜?小麥?豌豆?玉米;對種子的萌發(fā)指標而言,與重金屬形態(tài)變化的相關性排序依次為:發(fā)芽指數?活力指數?發(fā)芽率?發(fā)芽勢;對不同重金屬而言,重金屬在雞糞堆肥發(fā)酵過程中其生物毒性的大小依次為Zn?Cd?Cu?Cr?Ni;對重金屬不同形態(tài)而言,有效性較高的重金屬形態(tài)對植物種子的萌發(fā)具有一定的抑制作用。
[Abstract]:With China's scale, specialization, the rapid development of intensive livestock farming, feed additives contain large quantities of heavy metals are widely used, which leads to heavy metals in livestock manure seriously exceed the standard. As the organic fertilizer in farming in the process of long-term application, will not only lead to the accumulation of heavy metals in soil and plant, improper handling will cause serious environmental problems that endanger human health. Therefore, study on heavy metal speciation in the composting of chicken manure in the process of dynamic changes, proved the passivation mechanism of attapulgite, analysis has practical significance in application of biological toxicity of heavy metals resources to guide livestock waste and attapulgite in composting process in this study. Collected from Zhangye province Gansu city Ganzhou District Xiangxiang aquaculture farmers professional cooperatives chicken manure and concave convex is provided by the Gansu science and Technology Co., Ltd. Thailand attapulgite double stick for Experimental materials. Set 6 treatments were added in different proportions in chicken manure attapulgite, aerobic composting experiment. Through the determination of chicken manure compost fermentation process, Cd, Cr, Cu, Ni and Zn five kinds of heavy metals in different treatments in each sampling time (1,4,12,20,25,32 days) on the amount, morphology the distribution of BCR sequential extraction method, and correlation analysis of different heavy metals, different forms of different heavy metals, correlation and seed germination characteristics of different forms of attapulgite, add composting process of heavy metals in morphology and biological toxicity. The experimental results show that: (1) in chicken manure composting process of attapulgite added in compost 32 days after maturity, Cd, Cu, Cr in each treatment, the concentration of Ni and Zn were higher than that of compost before and with the increase of attapulgite addition ratio, showed more significant enrichment effect. (2) in attapulgite added chicken manure In the fermentation process of compost fertilizer, 32 days after maturity, the treatment of heavy metals in Cd, Cr, Ni and Zn morphological changes showed by unstable form transformation to stable state trend. Heavy metal Cu exhibited by unstable form of acid soluble and stable form of residue to other forms of trend. The proportion of different processing, the effect of passivation of heavy metals during composting of chicken manure, because of heavy metals vary, A3 (attapulgite: chicken manure 3:20) treatment passivation effect on heavy metal Cd and Cr A9 (best; attapulgite: chicken manure 9:20) treatment passivation effect on heavy metals Cu and Ni the best; A6 (attapulgite: Chicken manure 6:20) treatment passivation effect on heavy metal Zn. (3) the addition of attapulgite has significant influence on the speciation of heavy metals in compost. The acid soluble Cd, Cr, Cu, Ni and Zn, at the same time, with the increasing proportion of Attapulgite 鍔犲叾嫻撳害閫愭笎闄嶄綆;鍚屼竴鍑瑰嚫媯掓坊鍔犳瘮渚嬬殑澶勭悊涓，

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