本文選題：農(nóng)田土壤 + 鎘　； 參考：《浙江農(nóng)林大學(xué)》2017年碩士論文

【摘要】：隨著我國農(nóng)田土壤重金屬污染問題日趨嚴峻,農(nóng)產(chǎn)品安全越來越引起社會各界的高度關(guān)注。本論文采用田間實際采樣、溫室盆栽及田間微區(qū)試驗相結(jié)合的方法,分別通過對農(nóng)田土壤鎘(Cd)污染現(xiàn)狀、玉米低Cd品種篩選和Cd超積累植物對農(nóng)田土壤Cd富集吸收等角度,探討了(i)在Cd污染農(nóng)田種植低累積作物以提高農(nóng)產(chǎn)品的食用安全性以及(ii)利用超積累植物進行植物抽取修復(fù)以消除土壤污染,這兩個應(yīng)對農(nóng)田土壤污染策略的可行性。主要研究結(jié)果如下:對杭州郊縣某典型污染農(nóng)田土壤Cd污染進行的調(diào)查發(fā)現(xiàn),該地50%以上的土壤Cd濃度集中在0.3-0.6 mg/kg,土壤Cd濃度在GB15618-1995《土壤環(huán)境質(zhì)量標準》的二級標準以內(nèi)的點位占29.1%;稻米Cd濃度主要集中在0.2-1.0 mg/kg,點位比例占87.4%,而稻米Cd濃度符合食品衛(wèi)生標準(大米≤0.2 mg/kg)的僅占3.9%;對農(nóng)田土壤進行單因子污染指數(shù)法評價,對相應(yīng)點位稻米進行了健康風(fēng)險評價,發(fā)現(xiàn)研究區(qū)農(nóng)田土壤主要以輕污染為主,但92.3%的稻米存在Cd的潛在健康危害。將124個玉米品種種植于Cd污染農(nóng)田、測定和計算不同玉米品種對土壤Cd的富集系數(shù),并研究不同施肥、水分管理、土壤耕作等農(nóng)藝調(diào)控措施對玉米籽粒Cd吸收性的影響,分析結(jié)果顯示僅聯(lián)創(chuàng)1號和1615/鄭58兩個品種Cd超標,富集系數(shù)偏高,不適宜在Cd污染農(nóng)田種植,其余均可;施肥處理措施下,玉米品種鄭單958籽粒樣品的Cd吸收量對肥料施用的響應(yīng)與先玉335不同;與對照處理比較,單施雞糞、單施磷肥、單施鋅肥、混施磷肥和鋅肥均顯著降低鄭單958玉米品種籽粒中Cd濃度,降低了14.3-20.0%;而先玉335玉米品種籽粒中Cd的濃度分別顯著增加了29.0-42.0%;水分管理和土壤耕作措施對兩種玉米籽粒中Cd濃度的影響均不顯著。溫室盆栽試驗研究了伴礦景天在不同土壤類型和緊實度條件下的生長狀況及對鎘吸收富集的影響,結(jié)果發(fā)現(xiàn):與無壓實處理比較,生長于低緊實度的砂質(zhì)壤土、壤黏土和黏土中伴礦景天地上部生物量顯著下降了66.8-83.5%、59.9-60.4%和57.9-71.4%,總體看來高緊實度對伴礦景天地上部生物量影響更大,高緊實度處理顯著提高了伴礦景天的根系活力(142-241%)。高緊實度處理顯著降低了壤黏土上伴礦景天地上部Cd濃度(35.6%),但低緊實度對砂質(zhì)壤土和黏土上伴礦景天地上部Cd濃度無顯著影響。與無壓實處理比較,低緊實度顯著降低了砂質(zhì)壤土、壤黏土和黏土上伴礦景天的Cd吸取量,分別下降50.4-73.8%、61.4-74.9%和43.4-63.3%,土壤緊實度對壤黏土上伴礦景天的鎘鋅吸取效率影響最為明顯。
[Abstract]:With the pollution of heavy metals in farmland soil is becoming more and more serious, the safety of agricultural products has attracted more and more attention from all walks of life.In this paper, the methods of field sampling, greenhouse potted cultivation and field microregional experiment were used to study the present situation of CD / CD pollution in farmland soil, the selection of maize low CD varieties and the CD enrichment and absorption by CD superaccumulators.This paper discusses the feasibility of planting low accumulation crops in CD polluted farmland to improve the edible safety of agricultural products, and using superaccumulative plants to carry out plant extraction and repair to eliminate soil pollution, and the feasibility of these two strategies to deal with farmland soil pollution.The main results are as follows: the investigation of CD pollution in a typical polluted farmland in a suburb county of Hangzhou,More than 50% of the soil CD concentration in this area is 0.3-0.6 mg / kg, the CD concentration in the soil is 29.1% in the second grade standard of GB15618-1995, and the CD concentration in rice is mainly 0.2-1.0 mg / kg, the percentage of point is 87.4%, and the CD concentration in rice is consistent with that of rice.The proportion of food hygiene standard (rice 鈮，

本文編號：1751364