本文選題：鹽膚木 + 鉛�。� 參考：《中國(guó)林業(yè)科學(xué)研究院》2017年博士論文

【摘要】：土壤重金屬污染已成為深受全球關(guān)注的環(huán)境問題之一。鉛是一種對(duì)人體危害極大的有毒重金屬,鉛可通過食物鏈對(duì)人體健康造成威脅。因此修復(fù)鉛污染土壤顯得十分緊迫。植物修復(fù)技術(shù)是一種綠色、低成本的土壤污染修復(fù)技術(shù)。前期研究中發(fā)現(xiàn)鹽膚木(Rhus chinensi Mill)在礦區(qū)環(huán)境中,對(duì)鉛有良好的吸收轉(zhuǎn)運(yùn)能力。因此,明確鹽膚木對(duì)鉛的吸收轉(zhuǎn)運(yùn)過程,闡明其轉(zhuǎn)運(yùn)鉛的內(nèi)在機(jī)制,不僅有助于人們了解木本植物鉛的轉(zhuǎn)運(yùn)途徑及其運(yùn)輸機(jī)制,也將為土壤重金屬鉛污染植物修復(fù)提供科學(xué)依據(jù)。本研究通過土培和水培模擬試驗(yàn)深入探討鹽膚木對(duì)鉛的吸收和耐性機(jī)制,揭示鹽膚木根系對(duì)鉛的吸收、累積、分布機(jī)理;鉛在鹽膚木體內(nèi)的化學(xué)形態(tài)及亞細(xì)胞分布;根細(xì)胞壁在鉛累積中的作用。主要研究結(jié)果如下:(1)鉛脅迫下,鹽膚木生物量減少,光合色素含量減少,膜脂過氧化程度顯著加大;鹽膚木表現(xiàn)出一定的毒害癥狀;同時(shí)抗氧化酶活性有升高的趨勢(shì)。表明鹽膚木能夠耐受中等濃度鉛引起的氧化脅迫,并且通過響應(yīng)抗氧化體系來實(shí)現(xiàn)自我保護(hù)。土培和水培條件下,鉛主要富集在植物根系,特別是在側(cè)根。細(xì)胞壁是鉛主要積累位點(diǎn),其次積累在可溶性組分。鉛在植物體內(nèi)主要以醋酸提取態(tài)、鹽酸提取態(tài)和氯化鈉提取態(tài)等形態(tài)存在。鉛脅迫下顯著降低了鉛分布在細(xì)胞壁的比例;而活性較強(qiáng)的氯化鈉提取態(tài)鉛所占比例增加。這種現(xiàn)象的發(fā)生可能是植物生物量下降的主要原因。鉛脅迫下鹽膚木幼苗根系分泌物中草酸濃度顯著增加,同時(shí)會(huì)誘導(dǎo)根系產(chǎn)生蘋果酸和檸檬酸,且濃度隨著鉛濃度增加而增加,表明植物可以利用不同形式的有機(jī)酸與鉛離子螯合并將其運(yùn)輸至可收獲部分。土培和水培下鹽膚木鉛轉(zhuǎn)移系數(shù)分別為0.21-0.55和0.19-0.44,表明鹽膚木具有一定的鉛轉(zhuǎn)移能力。(2)鹽膚木根細(xì)胞壁(CW)及其組分(CW1、CW2和CW3)對(duì)鉛的吸附試驗(yàn)結(jié)果表明:細(xì)胞壁中的纖維素、果膠、木質(zhì)素等在鉛吸附中的貢獻(xiàn)較大;同時(shí)蛋白也參與到鉛吸附中。吸附動(dòng)力學(xué)分析表明孔內(nèi)擴(kuò)散進(jìn)程不是唯一的限速步驟。Freundlich模型可較好描述鹽膚木細(xì)胞壁及其各組分的鉛吸附過程并表明這個(gè)過程是良好的。熱力學(xué)分析表明所有鹽膚木根細(xì)胞壁材料的吸附過程均是吸熱的。(3)鹽膚木根系對(duì)鉛的吸收同溶液中鉛活度有關(guān)。噴施蒸騰抑制劑后,蒸騰量有顯著下降,但兩個(gè)處理組根系中鉛濃度無顯著差異。低溫處理和兩種代謝抑制劑處理則顯著抑制鹽膚木根系對(duì)鉛的吸收,但并不能完全抑制根系的主動(dòng)吸收。因此通過以上幾個(gè)試驗(yàn)表明鹽膚木根系對(duì)鉛的吸收可能是兩種吸收類型共存,且共質(zhì)體途徑貢獻(xiàn)率為23.9%。鹽膚木各組織中鉛濃度與吸收液中鉛濃度呈顯著正相關(guān),鹽膚木各組織對(duì)不同濃度鉛的吸收過程可用改良Michaelis-Menten方程描述,初步表明鹽膚木對(duì)鉛的吸收是通過載體進(jìn)行的。(4)水培試驗(yàn)表明低濃度鈣顯著抑制了鹽膚木根系對(duì)鉛的吸收,但高濃度鈣處理(2mmol·L-1和4 mmol·L-1)則促進(jìn)了鹽膚木根系對(duì)鉛的吸收。添加鈣離子通道抑制劑和蛋白合成抑制劑后,鹽膚木根系鉛濃度也較對(duì)照有顯著減少。通過以上試驗(yàn)結(jié)果可知鹽膚木對(duì)鉛的吸收可能與鈣離子通道有關(guān)并受膜上蛋白調(diào)控。但高鈣處理下鹽膚木根系濃度高于對(duì)照組,表明鹽膚木可能還存在其它陽(yáng)離子通道運(yùn)輸途徑。鉛脅迫下,鹽膚木植物體內(nèi)鈣和鉀濃度減少。同時(shí)根系中鈣和鉀離子流速數(shù)據(jù)表明鉛干擾了鹽膚木對(duì)鈣和鉀的吸收。鈣和鉀離子的穩(wěn)態(tài)平衡被打破,這可能是鉛造成鹽膚木毒害的原因之一。(5)試驗(yàn)結(jié)果表明,草酸和檸檬酸的添加未對(duì)鹽膚木產(chǎn)生明顯的生理毒害效應(yīng)。其中,低濃度檸檬酸(0.5 mmol·L-1)和高濃度草酸(1.0 mmol·L-1)試驗(yàn)組各指標(biāo)的變化趨勢(shì)比其它試驗(yàn)組更為靈敏。低濃度檸檬酸(0.5 mmol·L-1)能促進(jìn)鹽膚木鉛吸收。相反草酸的添加并未使得鹽膚木根系能吸收更多的鉛。外源檸檬酸和草酸可以在一定程度上促進(jìn)植物對(duì)鉛的轉(zhuǎn)運(yùn)。鉛在植物體內(nèi)主要以有效性較低的提取態(tài)(醋酸提取態(tài)、鹽酸提取態(tài)和氯化鈉提取態(tài))存在,因此外源檸檬酸和草酸與鉛形成金屬螯合物能夠緩解鉛離子對(duì)植物體的毒害。
[Abstract]:Heavy metal pollution in soil has become one of the environmental problems that are deeply concerned around the world. Lead is a kind of toxic heavy metal which is very harmful to human body. Lead can threaten human health through food chain. Therefore, it is very urgent to repair lead contaminated soil. Phytoremediation technology is a green, low cost soil remediation technology. It is found that Rhus Chinensi Mill has good absorption and transport ability to lead in the mining environment. Therefore, it is not only helpful for people to understand the transport mechanism of lead and its transport mechanism, but also for the plant of heavy metal lead pollution in the soil. This study provides a scientific basis for the study. This study explored the absorption and tolerance mechanism of saline wood to lead by soil culture and hydroponic simulation, and revealed the absorption, accumulation and distribution of lead in the root system of the salt skin, the chemical form and subcellular distribution of lead in skin and the role of the root cell wall in the accumulation of lead. The main results are as follows: (1) lead stress Under the pressure, the biomass of Rhus chinensis decreased, the content of photosynthetic pigments decreased, the degree of membrane lipid peroxidation increased significantly; the salt skin showed certain toxic symptoms, and the activity of antioxidant enzymes increased. It indicated that the saline wood could tolerate the oxidative stress caused by moderate concentration of lead and realized self protection by response to the antioxidant system. Under the condition of hydroponics, lead is mainly enriched in plant roots, especially in lateral roots. Cell wall is the main accumulation site of lead, followed by the accumulation of soluble components. Lead is mainly in the form of acetic acid extraction, extraction state of hydrochloric acid and extraction state of sodium chloride in the plant. The proportion of lead in cell wall is significantly reduced under lead stress; and the activity is more than that of lead. This phenomenon may be the main reason for the decrease of plant biomass. The concentration of oxalic acid in root exudates of the seedlings under lead stress is significantly increased, and the root production of malic acid and citric acid will be induced, and the concentration increases with the increase of the concentration of lead, indicating that plants can be used not. The same form of organic acid was combined with lead ion chelate and transported to the reacable part. The transfer coefficient of lead in soil culture and hydroponics was 0.21-0.55 and 0.19-0.44 respectively, indicating that the salt skin had a certain ability of lead transfer. (2) the results of the adsorption test of the root cell wall (CW) and its components (CW1, CW2 and CW3) on the lead showed that the fiber in the cell wall was the fiber. The contribution of vitamin, pectin and lignin to lead absorption is great, and the protein also participates in the lead absorption. Adsorption kinetics analysis shows that the process of intraporm diffusion is not the only speed limit step.Freundlich model, which can better describe the lead adsorption process of the cell wall and its components and show that this process is good. The adsorption process of all the root cell wall materials of the salt skin was endothermic. (3) the absorption of lead in the root system of the salt skin was related to the lead activity in the solution. After spraying transpiration inhibitors, the transpiration decreased significantly, but there was no significant difference in the lead concentration in the roots of the two treatment groups. The low temperature treatment and the treatment of two kinds of metabolic inhibitors significantly inhibited the salt skin. The root system absorbs lead, but it does not completely inhibit the active absorption of root system. Therefore, these experiments show that the absorption of lead in the root system of the salt skin may be two types of absorption, and the contribution rate of the common plastid pathway is the significant positive correlation between the lead concentration and the lead concentration in the absorption solution of 23.9%.. The absorption process of different concentrations of lead can be described by the modified Michaelis-Menten equation. It is preliminarily indicated that the absorption of lead in salinwood is carried out through the carrier. (4) the hydroponic test shows that low concentration of calcium significantly inhibits the absorption of lead in the root system of the salt skin, but the high concentration calcium treatment (2mmol. L-1 and 4 mmol. L-1) promotes the absorption of lead in the root system of the salt skin. After adding calcium ion channel inhibitors and protein synthesis inhibitors, the lead concentration in the root system of the salt skin was also significantly reduced. The results showed that the absorption of lead could be related to the calcium channel and regulated by the protein on the membrane. However, the root concentration of the salt skin was higher than that of the control group, indicating the possibility of the salt skin. There are other channels of cation channel transport. Under lead stress, the concentration of calcium and potassium in the plant body is reduced. At the same time, the data of calcium and potassium ions in the root system show that lead interferes with the absorption of calcium and potassium. The steady equilibrium of calcium and potassium ions is broken, which may be one of the causes of the toxicity of lead. (5) experimental results. The results showed that the addition of oxalic acid and citric acid did not produce obvious physiological toxic effects on the salt skin. Among them, the change trend of low concentration citric acid (0.5 mmol. L-1) and high concentration oxalic acid (1 mmol. L-1) test group was more sensitive than that of other experimental groups. Low concentration citric acid (0.5 mmol. L-1) could promote the absorption of lead in salt skin. The addition of citric acid and oxalic acid can promote the transport of lead to plants to a certain extent. The lead in plants is mainly in the presence of low availability (acetic acid extraction state, hydrochloric acid extraction state and sodium chloride extraction state) in plants, and the metal chelate is formed because of the exogenous citric acid and oxalic acid and lead. Things can relieve the toxic effects of lead ions on plants.
【學(xué)位授予單位】：中國(guó)林業(yè)科學(xué)研究院
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2017
【分類號(hào)】：X173;X53

【相似文獻(xiàn)】

相關(guān)期刊論文 前10條

1 曲青山;室內(nèi)外空氣中鉛濃度[J];國(guó)外醫(yī)學(xué)參考資料(衛(wèi)生學(xué)分冊(cè));1975年01期

2 小康;曝露于低濃度鉛會(huì)降低嬰幼兒智力[J];環(huán)境科學(xué);1993年03期

3 ;環(huán)境衛(wèi)生與監(jiān)測(cè)[J];中國(guó)婦幼衛(wèi)生雜志;1992年02期

4 王金達(dá),劉景雙,于君寶,王春梅,王艷,張學(xué)林;沈陽(yáng)市區(qū)環(huán)境空氣中鉛的污染表征[J];城市環(huán)境與城市生態(tài);2003年S1期

5 龔建福;;長(zhǎng)期喂飼含鉛飲食的雄性大鼠軟組織中的鉛濃度[J];新疆環(huán)境保護(hù);1985年S1期

6 盛葉舟;;接觸生產(chǎn)中低濃度鉛時(shí)尿δ-ALA的變化[J];鐵道勞動(dòng)衛(wèi)生通訊;1984年04期

7 李繼強(qiáng),鄭惠華,陳錫永,盧志堅(jiān),陳政池,謝廣寧;韶關(guān)市區(qū)交通干道汽車流量、大氣鉛濃度及人群血鉛、血δ-ALAD活力的調(diào)查[J];環(huán)境與健康雜志;1991年03期

8 李繼強(qiáng),鄭惠華,陳錫永,盧志堅(jiān),陳政池,謝廣寧;韶關(guān)市區(qū)交通干道大氣鉛濃度及其對(duì)人群健康影響的初步調(diào)查[J];環(huán)境與健康雜志;1991年05期

9 楊端,周仁珍;用魚血δ-氨基乙酰丙酸脫水酶指示水體中鉛污染的研究[J];環(huán)境科學(xué)學(xué)報(bào);1981年01期

10 錢耀忠;張唯一;方翠萍;;2009—2011年上海市奉賢區(qū)5家蓄電池生產(chǎn)企業(yè)鉛濃度的監(jiān)測(cè)結(jié)果[J];職業(yè)與健康;2013年10期

相關(guān)會(huì)議論文 前4條

1 劉愛榮;張遠(yuǎn)兵;李百學(xué);高紅梅;;鉛脅迫下高羊茅植株無機(jī)離子分布的響應(yīng)特點(diǎn)研究[A];中國(guó)植物學(xué)會(huì)七十五周年年會(huì)論文摘要匯編（1933-2008）[C];2008年

2 孫華;白瑞琴;樊明壽;韓蕾;李燕;孫振元;;鎘、鉛脅迫下野生地被植物甘野菊生理生化響應(yīng)的研究[A];2007自然科學(xué)學(xué)術(shù)論文（土壤肥料與農(nóng)業(yè)可持續(xù)發(fā)展）[C];2007年

3 高海英;;鉛脅迫對(duì)冰草生長(zhǎng)和生理生化特性的研究[A];科技創(chuàng)新與經(jīng)濟(jì)結(jié)構(gòu)調(diào)整——第七屆內(nèi)蒙古自治區(qū)自然科學(xué)學(xué)術(shù)年會(huì)優(yōu)秀論文集[C];2012年

4 李永杰;李吉躍;蔡囊;;鉛脅迫對(duì)大葉黃楊鉛積累量及葉片生理特性的影響[A];2009重金屬污染監(jiān)測(cè)、風(fēng)險(xiǎn)評(píng)價(jià)及修復(fù)技術(shù)高級(jí)研討會(huì)論文集[C];2009年

相關(guān)博士學(xué)位論文 前2條

1 施翔;鹽膚木對(duì)鉛的吸收累積及耐性機(jī)制[D];中國(guó)林業(yè)科學(xué)研究院;2017年

2 Alieu Mohamed Bah（艾留）;香蒲耐鉻、鎘、鉛脅迫特異蛋白及生理機(jī)制的研究[D];浙江大學(xué);2011年

相關(guān)碩士學(xué)位論文 前10條

1 武敏;鹽膚木苯丙氨酸解氨酶基因的克隆及其功能性質(zhì)研究[D];山西大學(xué);2012年

2 段立柱;基于AFLP標(biāo)記的鹽膚木種群遺傳多樣性和遺傳結(jié)構(gòu)[D];山西大學(xué);2010年

3 高潔瑩;鹽膚木果粕成分研究[D];湖南中醫(yī)藥大學(xué);2015年

4 秦芳;鋅對(duì)鉛脅迫下桑樹雌雄幼苗生長(zhǎng)的影響[D];西華師范大學(xué);2015年

5 陳科皓;鉛脅迫下節(jié)律性干旱對(duì)紫穗槐和國(guó)槐生長(zhǎng)和生理特性的影響[D];西北農(nóng)林科技大學(xué);2015年

6 董萬春;擬南芥CDR6基因在調(diào)控鉛脅迫響應(yīng)中的功能研究[D];合肥工業(yè)大學(xué);2015年

7 王榆鑫;干旱和鉛對(duì)4種林木種子播種苗的脅迫閾值研究[D];西北農(nóng)林科技大學(xué);2016年

8 呂瀟;鉛脅迫下向日葵幼苗生理及蛋白質(zhì)組學(xué)的研究[D];天津農(nóng)學(xué)院;2016年

9 任紅菲;鉛脅迫對(duì)人參生長(zhǎng)與有效成分影響的研究[D];吉林農(nóng)業(yè)大學(xué);2016年

10 夾書珊;旱柳生長(zhǎng)過程對(duì)鉛脅迫的響應(yīng)機(jī)理研究[D];中南林業(yè)科技大學(xué);2016年

，

本文編號(hào)：2002223