鋁和鎘污染對(duì)磚紅壤土壤微生物及土壤呼吸的影響

王松林等

摘 要 通過(guò)室內(nèi)模擬土壤盆栽試驗(yàn)，研究鋁、鎘對(duì)磚紅壤土壤微生物及土壤呼吸的影響。結(jié)果表明：鋁和鎘對(duì)土壤生化過(guò)程有不同的效應(yīng)。鋁濃度≤100 mg/kg和≤50 mg/kg分別對(duì)細(xì)菌和放線菌有一定促進(jìn)作用，高濃度則產(chǎn)生抑制作用，土壤真菌數(shù)量隨土壤鋁濃度的增加而逐漸減少。而鎘對(duì)土壤微生物及土壤呼吸作用的影響比鋁小。鎘對(duì)細(xì)菌生長(zhǎng)影響波動(dòng)幅度大，鎘濃度在5～100 mg/kg時(shí)，對(duì)真菌生長(zhǎng)有促進(jìn)作用，而抑制放線菌的生長(zhǎng)。鋁對(duì)土壤呼吸作用抑制效果隨鋁處理濃度增加而增加，而不同鎘處理濃度對(duì)土壤呼吸作用影響較鋁的作用小。鋁鎘復(fù)合污染對(duì)土壤細(xì)菌和真菌的影響表現(xiàn)出協(xié)同效應(yīng)，對(duì)土壤放線菌的影響表現(xiàn)出拮抗效應(yīng)。

關(guān)鍵詞 鋁；鎘；土壤呼吸；土壤微生物

中圖分類號(hào) S154.3 文獻(xiàn)標(biāo)識(shí)碼 A

Abstract A pot experiment was conducted to study the impacts of aluminum（Al）and cadmium（Cd）pollution on the soil microbes and soil respiration. The results indicated that the pollution effects of Al and Cd on the biochemistry processes were different， The lower concentration of Al， ≤100 mg/kg and ≤50 mg/kg could promote the growth of bacteria and actinomycete， but the higher concentrations of Al could reducd bacteria and actinomycetes number. The number of fungi was gradually reducing with the increasing of the concentration of Al. While， the influence degree of Cd on the soil microbe and soil respiration was weaker than that of Al. The influence of Cd on bacteria fluctuated very much， and the Cd under the concentration of 5-100 mg/kg promoted the fungi growth， and inhibited the growth of the actinomycetes. The Al inhibition on the soil respiration was according to the concentration of Al. However， the influence of Cd on soil respiration was less than that of Al. Synergistic effect on the population of bacteria and fungi under the compound pollution of Al and Cd， and antagonistic effect on the population of actinomycete.

Key words Aluminum； Cadmium； Soil respiration； Soil microbe

doi 10.3969/j.issn.1000-2561.2015.03.026

鋁（Al）是地殼中最豐富的元素之一，土壤鋁主要以鋁硅酸鹽礦物和氧化物等形態(tài)存在，對(duì)植物和環(huán)境影響很小。當(dāng)土壤發(fā)生酸化時(shí)，土壤中的活性鋁增加，導(dǎo)致鋁毒的產(chǎn)生。鋁毒不僅限制作物生長(zhǎng)[1-2]，而且對(duì)微生物和動(dòng)物產(chǎn)生毒害作用[3-4]。酸雨加速土壤固相鋁溶解，在酸雨頻發(fā)的地區(qū)、北歐和北美灰化地區(qū)，湖泊和河流發(fā)生嚴(yán)重酸化，對(duì)生態(tài)環(huán)境造成嚴(yán)重的危害[5-7]。從20世紀(jì)80年代到現(xiàn)在，我國(guó)土壤酸化越來(lái)越嚴(yán)重，尤其發(fā)生在南方酸性土壤，土壤酸化面積占我國(guó)耕地面積的40%以上[8]。

土壤微生物較植物對(duì)環(huán)境脅迫更敏感。有研究報(bào)道土壤酸化與土壤微生物參數(shù)的關(guān)系[9]；……