本文關(guān)鍵詞： 鎘 中國土壤 赤子愛勝蚓 毒性效應(yīng) 生態(tài)閾值　出處：《蘇州科技學(xué)院》2015年碩士論文　論文類型：學(xué)位論文

【摘要】：本文選用我國18種典型田間土壤,采用OECD頒布的標(biāo)準(zhǔn)方法研究了鎘在不同類型土壤中對模式動(dòng)物赤子愛勝蚓的急性毒性和慢性毒性,獲取基于不同的測試終點(diǎn)土壤鎘生態(tài)毒性閾值。探討了土壤性質(zhì)對鎘的生態(tài)閾值的影響并建立了在蚯蚓生物毒性基礎(chǔ)上基于土壤性質(zhì)的鎘的生態(tài)閾值預(yù)測模型。(1)急性毒性試驗(yàn)結(jié)果表明,土壤類型對Cd對蚯蚓的急性毒性有較大的影響,鎘在鷹潭紅壤中的毒性表現(xiàn)最強(qiáng),而在貴陽黃壤中的毒性最弱,Cd在不同土壤中的引起蚯蚓半數(shù)致死毒性閾值LC的變化范圍為440.7-1520.4mg/kg。將Cd的毒性閾值LC_(50)與主要的土壤理化性質(zhì)(土壤pH值、陽離子交換量、有機(jī)質(zhì)含量和粘粒含量)進(jìn)行相關(guān)性分析,發(fā)現(xiàn)土壤pH值和有機(jī)質(zhì)含量是導(dǎo)致Cd在不同類型土壤中毒性差異的主要因素,二者與LC_(50)呈顯著正相關(guān)關(guān)系。分析土壤中有效態(tài)Cd含量與蚯蚓體內(nèi)Cd積累量,二者顯著正相關(guān)。土壤理化性質(zhì)通過影響土壤有效態(tài)Cd含量,影響蚯蚓體內(nèi)Cd積累量,進(jìn)而對蚯蚓Cd毒性產(chǎn)生影響。(2)慢性毒性試驗(yàn)結(jié)果表明,赤子愛勝蚓的生長發(fā)育(體重變化)對Cd的響應(yīng)不太敏感,大多數(shù)土壤中只有當(dāng)鎘濃度達(dá)到較高水平(200 mg/kg)時(shí)才對蚯蚓的體重產(chǎn)生比較明顯的抑制效應(yīng),而反映赤子愛勝蚓生殖的測試終點(diǎn)(產(chǎn)繭量)對Cd的響應(yīng)十分敏感。不同類型土壤中Cd對蚯蚓產(chǎn)繭量的影響差異較大,其中Cd抑制赤子愛勝蚓產(chǎn)繭的毒性閾值EC_(50)作用范圍為66.5 263.5 mg/kg。將Cd的毒性閾值EC_(50)值與主要的土壤理化性質(zhì)進(jìn)行相關(guān)性分析,發(fā)現(xiàn)土壤pH值和有機(jī)質(zhì)含量與EC_(50)呈顯著正相關(guān)關(guān)系,粘粒與EC_(50)呈顯著負(fù)相關(guān)關(guān)系。同時(shí)分析不同類型土壤中蚯蚓體內(nèi)鎘積累量變化,土壤pH越高,有機(jī)質(zhì)含量越高,土壤中Cd生物有效性就越低。(3)針對影響土壤鎘的生態(tài)閾值預(yù)測模型的重要環(huán)境特征—有機(jī)質(zhì)(以低分子有機(jī)酸為例),模擬土壤溶液,探究其影響鎘毒性/生物有效性內(nèi)在機(jī)制,發(fā)現(xiàn)有機(jī)質(zhì)與重金屬鎘離子形成金屬有機(jī)配合物,從而降低了土壤溶液中自由態(tài)鎘離子,進(jìn)而降低了重金屬鎘的毒性,其解毒能力大小取決于有機(jī)質(zhì)與金屬所形成有機(jī)配合物時(shí)絡(luò)合常數(shù),絡(luò)合常數(shù)越大,解毒能力越強(qiáng),金屬鎘的毒性也就越低。本論文研究結(jié)果可為評價(jià)我國土壤鎘的生態(tài)風(fēng)險(xiǎn)和建立土壤Cd生態(tài)閾值提供依據(jù)。
[Abstract]:In this paper, the acute and chronic toxicity of cadmium to model animal Aicheng vermis in different types of soils was studied by using the standard method issued by OECD in 18 typical field soils in China. The ecological toxicity threshold of cadmium in soil based on different testing endpoints was obtained. The effects of soil properties on ecological threshold of cadmium were discussed and a prediction model of ecological threshold of cadmium based on soil properties was established based on the biological toxicity of earthworm. The results of acute toxicity test showed that. Soil type had a great effect on the acute toxicity of CD to earthworms, and cadmium had the strongest toxicity in Yingtan red soil. The toxicity of CD in yellow soil of Guiyang was the weakest, and the LC50 of LC50 caused by CD in different soils ranged from 440.7-1520.4 mg / kg. The toxicity threshold of CD LCSP 50 was compared with the main soil physical and chemical properties (soil pH value, cation exchange capacity, and so on). The correlation analysis of organic matter content and clay content showed that pH value and organic matter content were the main factors that led to the difference of CD toxicity in different types of soils. The content of available CD in soil and the accumulation of CD in earthworm were positively correlated. The physical and chemical properties of soil affected the accumulation of CD in earthworm by affecting the content of available CD in soil. The results of chronic toxicity test showed that the growth and development (body weight change) of Aisheng earthworm was not sensitive to CD. In most soils, only when cadmium concentration reached a high level of 200 mg / kg did the weight of earthworms be inhibited significantly. But the test end point (cocoon yield) which reflects the reproduction of Aisheng vermis is very sensitive to the response of CD. The effect of CD on the cocoon production of earthworm in different types of soil is quite different. The toxicity threshold of CD on cocoon production of Aisheng earthworm was 66.5 ~ 263.5 mg / kg 路kg ~ (-1). The correlation between the toxicity threshold of CD and the physical and chemical properties of soil was analyzed. It was found that soil pH value and organic matter content were positively correlated with ECS _ (50). There was a significant negative correlation between clay and ECS 50. At the same time, the change of cadmium accumulation in earthworm in different types of soil was analyzed. The higher the soil pH, the higher the content of organic matter. The lower the CD bioavailability in soil is, the lower the CD bioavailability is.) aiming at the important environmental characteristics of the ecological threshold prediction model affecting soil cadmium-organic matter (taking low molecular organic acid as an example, simulating soil solution to explore the intrinsic mechanism of its effect on cadmium toxicity / bioavailability, It is found that organic matter forms organometallic complexes with heavy metal cadmium ions, thus reducing the free state cadmium ions in soil solution and thus reducing the toxicity of heavy metal cadmium. The degree of detoxification ability depends on the complexation constant of organic complex formed by organic matter and metal. The larger the complexation constant is, the stronger the detoxification ability is. The toxicity of cadmium is also lower. The results of this paper can be used to evaluate the ecological risk of soil cadmium and to establish the ecological threshold of soil CD in China.
【學(xué)位授予單位】：蘇州科技學(xué)院
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：X53

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 宋文恩;陳世寶;;基于水稻根伸長的不同土壤中鎘(Cd)毒性閾值(EC_x)及預(yù)測模型[J];中國農(nóng)業(yè)科學(xué);2014年17期

2 余淑娟;高樹芳;屈應(yīng)明;陳炎輝;王果;;不同土壤條件下鎘對番茄根系的毒害效應(yīng)及其毒害臨界值研究[J];農(nóng)業(yè)環(huán)境科學(xué)學(xué)報(bào);2014年04期

3 王小慶;李菊梅;韋東普;陳世寶;馬義兵;黃占斌;;土壤中銅生態(tài)閾值的影響因素及其預(yù)測模型[J];中國環(huán)境科學(xué);2014年02期

4 夏偉霞;譚長銀;萬大娟;楊燕;張莎娜;;土壤溶解性有機(jī)質(zhì)對重金屬環(huán)境行為影響的研究進(jìn)展[J];中國資源綜合利用;2014年01期

5 孫聰;陳世寶;馬義兵;劉繼芳;;基于物種敏感性分布(Burr-Ⅲ)模型預(yù)測Cd對水稻毒害的生態(tài)風(fēng)險(xiǎn)閾值HC_5[J];農(nóng)業(yè)環(huán)境科學(xué)學(xué)報(bào);2013年12期

6 鄧朝陽;朱霞萍;郭兵;王小玉;吳九九;張軍;;不同性質(zhì)土壤中鎘的形態(tài)特征及其影響因素[J];南昌大學(xué)學(xué)報(bào)(工科版);2012年04期

7 周啟星;王毅;;我國農(nóng)業(yè)土壤質(zhì)量基準(zhǔn)建立的方法體系研究[J];應(yīng)用基礎(chǔ)與工程科學(xué)學(xué)報(bào);2012年S1期

8 吳聲敢;王彥華;吳長興;陳麗萍;蒼濤;俞瑞鮮;安雪花;李崗;趙學(xué)平;;6種重金屬對赤子愛勝蚓的急性毒性效應(yīng)與風(fēng)險(xiǎn)評價(jià)[J];生物安全學(xué)報(bào);2012年03期

9 楊雪峰;葛亞明;姜金慶;徐之勇;崔艷紅;王自良;;氯化鎘對小鼠的急性毒性效應(yīng)[J];中國獸醫(yī)學(xué)報(bào);2012年03期

10 王小慶;馬義兵;黃占斌;;土壤中鎳生態(tài)閾值的影響因素及預(yù)測模型[J];農(nóng)業(yè)工程學(xué)報(bào);2012年05期

，

本文編號(hào)：1546668