草本植物根際多環(huán)芳烴降解對(duì)氮沉降增加的短期響應(yīng)
發(fā)布時(shí)間：2018-07-13 10:32
【摘要】：植物根際降解土壤中污染物是植物修復(fù)技術(shù)中非常重要的一部分,是土壤學(xué)、植物學(xué)、毒理生態(tài)學(xué)及環(huán)境科學(xué)等學(xué)科重要研究前沿之一。尤其是在氮沉降日益增加的大環(huán)境下,少量的氮沉降會(huì)在短期內(nèi)提高生態(tài)系統(tǒng)生產(chǎn)力,積累更多生物量,而過量的氮沉降會(huì)導(dǎo)致植物營(yíng)養(yǎng)過剩、土壤酸化,影響生態(tài)系統(tǒng)穩(wěn)定性等危害。那么,在干旱區(qū),氮沉降的增加是否會(huì)影響石化工廠周邊草場(chǎng)植被對(duì)多環(huán)芳烴(Polycyclic Aromatic Hydrocarbons,PAHs)的降解能力,若有降解,那么其降解機(jī)制和隨氮沉降增加所發(fā)生的變化又是什么,都還有待研究。這對(duì)土壤污染修復(fù)和生態(tài)環(huán)境管理與建設(shè)都具有一定的參考價(jià)值。研究通過在新疆獨(dú)山子區(qū)石化工廠周邊模擬氮沉降增加試驗(yàn),經(jīng)分析當(dāng)?shù)夭份�、旱麥草、四齒芥三種優(yōu)勢(shì)草本植物,篩選出根際土壤環(huán)境狀況、酶活性以及微生物功能多樣性較好的博樂蒿為主要研究對(duì)象,設(shè)置CK(無任何處理)、N0(0 kg N/hm~2·a)、N1(10 kg N/hm~2·a)、N2(30 kg N/hm~2·a)、N3(90 kg N/hm~2·a)共五個(gè)處理,每隔一個(gè)月進(jìn)行一次氮添加,于2016年5月25日始至2016年8月19日終,對(duì)施氮前后的土壤樣品進(jìn)行分析和比較。得到如下結(jié)果:(1)不同植物根際與非根際土微生物代謝強(qiáng)度不同,博樂蒿根際土具有較好的微生物代謝活性(AWCD);各植物根際土壤微生物AWCD、優(yōu)勢(shì)度指數(shù)(Simpson)、豐富度指數(shù)(Shannon)、均勻度指數(shù)(McIntosh)均大于非根際土;且根際土壤微生物對(duì)糖類、脂類、酸類和胺類碳源物質(zhì)比較敏感,非根際土壤微生物敏感于酸類、氨基酸類以及糖類碳源物質(zhì),根際土壤微生物的碳源利用寬度更大。研究表明,植被的存在能夠促進(jìn)土壤酶活性、提高土壤微生物代謝活性和功能多樣性,土壤狀況越好,越有利于適應(yīng)環(huán)境變化。三種植物根際與非根際土壤的脫氫酶、過氧化氫酶和脲酶活性的分析中,博樂蒿根際與非根際土壤的三種酶活性均最高,且三種植物根際土壤酶活性均大于非根際土。與土壤化學(xué)性質(zhì)的相關(guān)分析發(fā)現(xiàn),影響土壤微生物功能多樣性的主要因子有pH、土壤有機(jī)質(zhì)(SOM)、速效磷(AP)和硝態(tài)氮(NO_3~--N);根際土壤中PAHs與土壤EC、土壤含水量和pH具有正效應(yīng);非根際土壤中,銨態(tài)氮(NH_4~+-N)和AP的增加能夠加強(qiáng)PAHs的去除效果。(2)氮沉降增加在短期內(nèi)(3個(gè)月)增強(qiáng)了博樂蒿根際土壤中脫氫酶、過氧化氫酶與脲酶活性;提高了根際土壤中的AWCD、Shannon和McIntosh,同時(shí)避免了根際微生物絕對(duì)優(yōu)勢(shì)種的出現(xiàn);能夠較好的減少土壤中2環(huán)(萘)與4環(huán)(屈)多環(huán)芳烴的含量,在總多環(huán)芳烴的去除效果中也存在一定的正效應(yīng)。短期不同水平氮添加處理中,30 kg N/hm~2·a的添加量對(duì)博樂蒿根際土壤中酶活性與微生物功能多樣性都具有較好的促進(jìn)作用,尤其是在PAHs的去除中,2~5環(huán)多環(huán)芳烴(分別為萘、菲、屈、苯并[a]芘)以及總多環(huán)芳烴的含量在此氮水平下均有顯著減少(P0.05)。博樂蒿根際土壤微生物在30 kg N/hm~2·a的氮添加處理中對(duì)六種碳源物質(zhì)的利用強(qiáng)度均最大,CK、N1、N2和N3處理主要利用的碳源物質(zhì)為脂類,對(duì)酸類物質(zhì)利用強(qiáng)度最小;無氮添加和無水處理組的根際土壤微生物對(duì)碳源的利用能力較弱,表明氮沉降的增加能夠明顯改變土壤微生物功能多樣性;基于主成分分析,酸類、糖類、氨基酸類以及脂類是博樂蒿根際土壤微生物群落在不同氮沉降量環(huán)境中發(fā)生變化的主要敏感碳源。(3)模擬氮沉降增加后,博樂蒿根際與非根際土壤環(huán)境因子與酶類、微生物和PAHs之間相關(guān)分析表明,根際土壤中土壤含水量、SOM、AP、pH、NH_4~+-N和NO_3~--N含量的增多對(duì)土壤中多環(huán)芳烴的含量有消減作用,與施氮前相比,養(yǎng)分物質(zhì)的添加對(duì)根際降解PAHs具有一定促進(jìn)作用;非根際土壤中AP、NH_4~+-N與NO_3~--N對(duì)PAHs去除有一定的幫助,與氮添加處理前相比,NO_3~--N的加入同樣能夠促進(jìn)PAHs的去除�？傮w來看,大氣中NH_4~+-N和NO_3~--N的沉降能夠在短期內(nèi)有效促進(jìn)植物根際和非根際土壤中PAHs的去除。
[Abstract]:The degradation of pollutants in the rhizosphere of plants is a very important part of phytoremediation. It is one of the important research frontiers in soil science, botany, toxicology and environmental science. Especially in the environment of increasing nitrogen deposition, a small amount of nitrogen deposition will improve the productivity of the ecosystem and accumulate more life in the short term. The excess nitrogen deposition can lead to the excess plant nutrition, soil acidification, and the impact of the ecosystem stability. In the arid area, whether the increase of nitrogen deposition affects the degradation ability of the Polycyclic Aromatic Hydrocarbons (PAHs) in the perimeter of the petrochemical plant and the degradation mechanism and the following degradation mechanism It has a certain reference value for the remediation of soil pollution and the management and construction of the ecological environment. Through the experiment on the simulated nitrogen deposition in the vicinity of the petrochemical plant in Dushanzi District of Xinjiang, three dominant herbaceous plants of Artemisia Artemisia, dry wheat straw and four tooth mustard are analyzed. CK (no treatment), N0 (0 kg N/hm~2. A), N1 (10 kg N/hm~2. A), N2 (30 kg N/hm~2. A), five treatments (90 kg N/hm~2. A), a nitrogen addition every other month, starting from May 25, 2016 to 2016, were selected as the main research object. At the end of August 19th, the soil samples before and after nitrogen application were analyzed and compared. The results were as follows: (1) the microbial metabolic intensity of rhizosphere and non rhizosphere soil of different plants was different, and the rhizosphere soil of Artemisia Artemisia had better microbial metabolic activity (AWCD), AWCD, Simpson, and Shannon in rhizosphere soil of each plant. The evenness index (McIntosh) is greater than that of non rhizosphere soil, and the rhizosphere soil microorganism is more sensitive to carbohydrate, lipid, acid and amine carbon source, and the non rhizosphere soil microorganism is sensitive to acid, amino acid and carbohydrate source material, and the carbon source of rhizosphere soil microorganism is wider. The study shows that the existence of vegetation can promote soil. Soil enzyme activity and functional diversity improve soil microbial metabolism and functional diversity, the better the soil conditions, the more conducive to the adaptation to environmental changes. In the analysis of dehydrogenase, catalase and urease activity in the rhizosphere and non rhizosphere soils of three plants, the activities of three enzymes in the rhizosphere and non rhizosphere soil of the Artemisia Artemisia were the highest, and three kinds of plant rhizosphere soil enzymes. The correlation analysis between the soil chemical properties and the soil chemical properties showed that the main factors affecting the microbial functional diversity were pH, soil organic matter (SOM), available phosphorus (AP) and nitrate nitrogen (NO_3~--N), PAHs and EC in the rhizosphere soil, soil water content and pH, and ammonium nitrogen (NH_4~+-N) and AP in non rhizosphere soil. Increasing the removal efficiency of PAHs. (2) the increase of nitrogen deposition in the short term (3 months) enhanced dehydrogenase, catalase and urease activity in the rhizosphere soil of Artemisia Artemisia, increased AWCD, Shannon and McIntosh in rhizosphere soil, and avoided the emergence of absolute dominant species in rhizosphere microorganisms, and could better reduce the 2 ring (naphthalene) in soil. The content of 4 ring (flexion) polycyclic aromatic hydrocarbons also has a positive effect in the removal of total polycyclic aromatic hydrocarbons. In the short-term nitrogen addition treatment, the addition of 30 kg N/hm~2. A has a good promotion effect on the enzyme activity and microbial functional diversity in the rhizosphere soil of Artemisia Artemisia, especially in the removal of PAHs. The 2~5 ring is polycyclic aromatic. The content of hydrocarbons (naphthalene, phenanthrene, flexion, benzo [a] pyrene) and total polycyclic aromatic hydrocarbons (BAP) and total polycyclic aromatic hydrocarbons were significantly reduced at this nitrogen level (P0.05). The maximum utilization of six carbon source materials in the nitrogen addition treatment of 30 kg N/hm~2. A in the rhizosphere soil of Artemisia Artemisia was the most important carbon source material used in CK, N1, N2 and N3 treatment. The utilization of the rhizosphere soil microorganisms in the nitrogen free and anhydrous treatment groups was weak, indicating that the increase of nitrogen deposition could significantly change the microbial functional diversity of soil. Based on the principal component analysis, acids, carbohydrates, amino acids and lipids were different nitrogen settlements in the rhizosphere soil microbial communities of Artemisia bloomer. The main sensitive carbon sources in the environment were changed. (3) after the increase of simulated nitrogen deposition, the correlation analysis between the rhizosphere and the non rhizosphere soil environmental factors and enzymes, microorganisms and PAHs showed that the content of soil water content in rhizosphere soil, SOM, AP, pH, NH_4~+-N and NO_3~--N content increased to the content of polycyclic aromatic hydrocarbons in soil, and it was applied to the soil. Compared with nitrogen, the addition of nutrients can promote the degradation of PAHs in rhizosphere; AP, NH_4~+-N and NO_3~--N in non rhizosphere soil have some help to PAHs removal. Compared with the addition of nitrogen, NO_3~--N addition can also promote the removal of PAHs. Overall, the settlement of NH_4~+-N and NO_3~--N in large gas can be in the short term. PAHs removal in rhizosphere and non rhizosphere soil was promoted.
【學(xué)位授予單位】：新疆大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：X173;X53
[Abstract]:The degradation of pollutants in the rhizosphere of plants is a very important part of phytoremediation. It is one of the important research frontiers in soil science, botany, toxicology and environmental science. Especially in the environment of increasing nitrogen deposition, a small amount of nitrogen deposition will improve the productivity of the ecosystem and accumulate more life in the short term. The excess nitrogen deposition can lead to the excess plant nutrition, soil acidification, and the impact of the ecosystem stability. In the arid area, whether the increase of nitrogen deposition affects the degradation ability of the Polycyclic Aromatic Hydrocarbons (PAHs) in the perimeter of the petrochemical plant and the degradation mechanism and the following degradation mechanism It has a certain reference value for the remediation of soil pollution and the management and construction of the ecological environment. Through the experiment on the simulated nitrogen deposition in the vicinity of the petrochemical plant in Dushanzi District of Xinjiang, three dominant herbaceous plants of Artemisia Artemisia, dry wheat straw and four tooth mustard are analyzed. CK (no treatment), N0 (0 kg N/hm~2. A), N1 (10 kg N/hm~2. A), N2 (30 kg N/hm~2. A), five treatments (90 kg N/hm~2. A), a nitrogen addition every other month, starting from May 25, 2016 to 2016, were selected as the main research object. At the end of August 19th, the soil samples before and after nitrogen application were analyzed and compared. The results were as follows: (1) the microbial metabolic intensity of rhizosphere and non rhizosphere soil of different plants was different, and the rhizosphere soil of Artemisia Artemisia had better microbial metabolic activity (AWCD), AWCD, Simpson, and Shannon in rhizosphere soil of each plant. The evenness index (McIntosh) is greater than that of non rhizosphere soil, and the rhizosphere soil microorganism is more sensitive to carbohydrate, lipid, acid and amine carbon source, and the non rhizosphere soil microorganism is sensitive to acid, amino acid and carbohydrate source material, and the carbon source of rhizosphere soil microorganism is wider. The study shows that the existence of vegetation can promote soil. Soil enzyme activity and functional diversity improve soil microbial metabolism and functional diversity, the better the soil conditions, the more conducive to the adaptation to environmental changes. In the analysis of dehydrogenase, catalase and urease activity in the rhizosphere and non rhizosphere soils of three plants, the activities of three enzymes in the rhizosphere and non rhizosphere soil of the Artemisia Artemisia were the highest, and three kinds of plant rhizosphere soil enzymes. The correlation analysis between the soil chemical properties and the soil chemical properties showed that the main factors affecting the microbial functional diversity were pH, soil organic matter (SOM), available phosphorus (AP) and nitrate nitrogen (NO_3~--N), PAHs and EC in the rhizosphere soil, soil water content and pH, and ammonium nitrogen (NH_4~+-N) and AP in non rhizosphere soil. Increasing the removal efficiency of PAHs. (2) the increase of nitrogen deposition in the short term (3 months) enhanced dehydrogenase, catalase and urease activity in the rhizosphere soil of Artemisia Artemisia, increased AWCD, Shannon and McIntosh in rhizosphere soil, and avoided the emergence of absolute dominant species in rhizosphere microorganisms, and could better reduce the 2 ring (naphthalene) in soil. The content of 4 ring (flexion) polycyclic aromatic hydrocarbons also has a positive effect in the removal of total polycyclic aromatic hydrocarbons. In the short-term nitrogen addition treatment, the addition of 30 kg N/hm~2. A has a good promotion effect on the enzyme activity and microbial functional diversity in the rhizosphere soil of Artemisia Artemisia, especially in the removal of PAHs. The 2~5 ring is polycyclic aromatic. The content of hydrocarbons (naphthalene, phenanthrene, flexion, benzo [a] pyrene) and total polycyclic aromatic hydrocarbons (BAP) and total polycyclic aromatic hydrocarbons were significantly reduced at this nitrogen level (P0.05). The maximum utilization of six carbon source materials in the nitrogen addition treatment of 30 kg N/hm~2. A in the rhizosphere soil of Artemisia Artemisia was the most important carbon source material used in CK, N1, N2 and N3 treatment. The utilization of the rhizosphere soil microorganisms in the nitrogen free and anhydrous treatment groups was weak, indicating that the increase of nitrogen deposition could significantly change the microbial functional diversity of soil. Based on the principal component analysis, acids, carbohydrates, amino acids and lipids were different nitrogen settlements in the rhizosphere soil microbial communities of Artemisia bloomer. The main sensitive carbon sources in the environment were changed. (3) after the increase of simulated nitrogen deposition, the correlation analysis between the rhizosphere and the non rhizosphere soil environmental factors and enzymes, microorganisms and PAHs showed that the content of soil water content in rhizosphere soil, SOM, AP, pH, NH_4~+-N and NO_3~--N content increased to the content of polycyclic aromatic hydrocarbons in soil, and it was applied to the soil. Compared with nitrogen, the addition of nutrients can promote the degradation of PAHs in rhizosphere; AP, NH_4~+-N and NO_3~--N in non rhizosphere soil have some help to PAHs removal. Compared with the addition of nitrogen, NO_3~--N addition can also promote the removal of PAHs. Overall, the settlement of NH_4~+-N and NO_3~--N in large gas can be in the short term. PAHs removal in rhizosphere and non rhizosphere soil was promoted.
【學(xué)位授予單位】：新疆大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：X173;X53
【參考文獻(xiàn)】
相關(guān)期刊論文 前10條
1 周嘉聰;劉小飛;鄭永;紀(jì)宇v，
本文編號(hào)：2119053
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