催化燃烧／库仑滴定法测定植物叶片中硫

以三氧化钨为催化剂，燃烧处理植物叶片，硫转化为SO2，后者被吸收液吸收后采用库仑滴定法测定。方法快速简便，测定植物叶片中硫的含量，相对标准偏差为1．5％，适用于大批量样品的快速测定。     

Evaluation of a cost e ective technique for treating aquaculture water discharge using Lolium perenne Lam as a biofilter

Wastewater stabilization ponds generate low cost by-products that are useful for agriculture. The utilization of these by-products for soil amendment and as a source of nutrients for plants requires a high level of sanitation and stabilization of the organic matter, to maintain acceptable levels of soil, water and air quality. In this study, two aquaculture wastewater treatment systems; recirculating system and a floating plant bed system were designed to improve the quality of irrigation water in local communities with low income. In both systems the grass species Lolium perenne Lam was used as a plant biofilter while vegetable specie Amaranthus viridis was used to evaluate the performance of the system and the suitability of the phyto-treated water for irrigation. It was found that the harmful material removal rate for recirculating system was 88.9% for TAN （total ammonia nitrogen）, 90% for NO2--N, 64.8% for NO3--N while for floating plant bed system 82.7% for TAN, 82% for NO2--N and 60.5% for NO3--N. Comparative analysis of the efficiency of waste element removal between the two systems revealed that both systems performed well, however, plant growth was not robust for floating plant bed system while recirculating system is energy consuming. Although both systems did not attain sufficient levels of TN （total nitrogen） and TP （total phosphorus） load reduction, the treatment with L. perenne remarkably improved the irrigation water quality. A. viridis plants irrigated with the phyto-treated discharge water had lesser concentrations of heavy metals in their tissues compared to those irrigated with untreated discharge. The control plants irrigated with untreated discharge were also found to be highly lignified with few stems and small leaves.     

城市道路绿化带不同植物叶片附尘对大气污染的磁学响应

对上海市金沙江路两侧绿化带内24个常绿植物叶片样品进行了磁性与重金属测试,以探讨城市道路绿化带不同植物叶片附尘对大气污染的磁学响应.结果表明,χ、SIRM值分别在（4～59）×10-8m3.kg-1和（496～6 114）×10-6Am2.kg-1之间变化,S-300 mT在89%～98%之间变动.所有植物样品中χARM/χ〈4,χARM/SIRM〈30×10-5mA-1.磁性参数表明,植物叶片附尘以亚铁磁性矿物为主,磁性矿物颗粒以假单畴（PSD）-多畴（MD）为主.重金属元素Zn、Cu、Pb含量与反映亚铁磁性矿物含量的χ、SIRM、χARM呈显著正相关,可以将磁性参数SIRM作为叶片重金属元素的替代指标.推荐在上海地区广泛种植的广玉兰作为道路植物污染的指示植物。     

北京常见绿化树种叶片富集重金属能力研究

以北京地区常见绿化树种为研究对象,测定叶片和土壤重金属含量,对其季节变化规律和污染程度的相关性进行分析,探究植物叶片对土壤中重金属的富集能力.结果表明:①植物叶片中重金属Cu、Pb、Zn含量随季节变化(由春到冬)呈先下降后升高再下降的变化趋势;Cr含量变化呈先升高后下降的趋势,秋季达最高值;春、夏、秋这3季对Cu富集能力较强的为柳树和国槐,冬季为油松;对Cr、Pb富集能力较强的是国槐和侧柏,冬季为侧柏和白皮松;对Zn富集能力较强的为柳树和白皮松,冬季为侧柏;②由市中心至远郊,4种重金属(Cu、Cr、Pb、Zn)污染程度为:景山(C=2.48,C为污染系数)>奥林(C=1.27)>松山(C=1.20)>水关(C=1.18);③水关长城景区植物叶片中重金属含量变化较大,其它3个研究区域重金属含量排序为:景山>奥林>松山;同一树种叶片对不同重金属富集能力排序均为:Zn>Cu>Pb>Cr,且Zn含量与Cr含量差异极显著(P<0.01);④植物叶片中重金属含量与土壤中相应重金属元素污染程度呈二次多项式关系,除Cu元素外,其余3种重金属元素含量与土壤中重金属污染程度相关性较强,且相关系数均达0.9以上.     

黔西北土法炼锌废渣堆场修复植物叶片和废渣的生态化学计量特征

为探讨土法炼锌废渣堆场实现生态修复后废渣-植物系统中植物内稳性以及不同植被类型与氮磷限制的关系,选择黔西北威宁县猴场镇已开展生态修复达4年的土法炼锌废渣堆场为研究区域,以废渣堆场上生长良好的5种优势乔灌草植物即构树（Broussonetia papyrifera）、柳杉（Cryptomeria fortunei）、大叶醉鱼草（Buddleja davidii）、芦竹（Arundo donax）、三叶草（Trifolium repens L）为研究对象,研究5种优势植物在铅锌废渣堆场中碳（C）、氮（N）、磷（P）、钾（K）的生态化学计量特征及其相互关系。结果表明：不同优势植物修复的废渣中C、N含量较高,P、K含量较低,三叶草废渣中N、P含量显著高于其他植物（p<0.05）,有效氮、有效磷与速效钾表现为三叶草废渣较高,柳杉较低;各元素化学计量特征表现为C∶P > C∶K > C∶N > N∶P > N∶K > P∶K,三叶草废渣中N∶K、P∶K显著高于其余四种植物。5种植物叶片中N含量整体较低,草本植物三叶草N、P、K含量明显高于其余几种植物;通过叶片N∶P分析表明,除三叶草生长受P限制,其余4种植物生长都受N限制。废渣与植物叶片中养分含量间的相关性表明,植物叶片中N、P、K含量分别与废渣中有效态养分（N、P、K）含量呈显著正相关（p<0.05）。除叶片N∶P与废渣中有效态养分（N、P、K）含量呈正相关外,叶片中其余元素间的化学计量比均与废渣中有效态养分（N、P、K）含量呈负相关,其中叶片C∶K、P∶K与废渣中有效态养分（N、P、K）含量呈极显著负相关（p<0.01）。因此,废渣中N、P、K的有效性显著影响着植物叶片中N、P、K的含量及生态化学计量特征。     

模拟酸雨对水稻叶片荧光光谱特性的影响

通过水稻盆栽试验,研究了不同pH值的模拟酸雨对水稻叶片荧光光谱特性的影响。结果表明,高酸度的酸雨对450nm处的峰强以及685nm和740nm处的峰强比值产生较为明显的影响,且该影响随水稻生育期而变化,这揭示出利用激光诱导荧光技术监测酸雨影响作物生长的可行性     

Relationship between types of urban forest and PM2.5 capture at three growth stages of leaves

Particulate matter diameter ≤ 2.5 μm (PM_2.5) causes direct harm to human health. Finding forms of urban forest systems that with the ability to reduce the amount of particulate matter in air effectively is the aim of this study. Five commonly cultivated kinds of urban forest types were studied in Beijing city at three stages of leaf growth. Results show that the urban forest system is capable of storing and capturing dust from the air. The types of shrubs and broadleaf trees that have the ability to capture PM_2.5 from the air are most effective when leaves have fully developed. In the leafless season, the conifer and mixed tree types are the most effective in removing dust from the air. For all kinds of forest types and stages of leaf growth, the PM_2.5 concentration is highest in the morning but lower in the afternoon and evening. Grassland cannot control particles suspended in the air, but can reduce dust pollution caused by dust from the ground blown by the wind back into the air.     

用树叶、树皮含硫量监测包头市大气SO2污染的探讨

植物与周围环境不断进行着气体交换,当外界大气环境发生变化时,就会对植物产生影响,这种影响会在植物体有关部位以各种形式反映出来.研究表明,植物中含硫量与大气SO2浓度呈现出密切相关性,因此,可以通过植物含硫量来反映大气SO2的污染状况.     

贵州喀斯特山区植物叶片碳同位素组成研究

通过测定贵州喀斯特山区灌丛12种主要植物叶片的δ13C值,研究了该区植物叶片碳同位素组成特征,以及种间、生境差异和时空变化特征。研究结果表明:该区植物叶片的碳同位素组成的变化范围为-26.98‰--29.15‰,平均值为-28.14‰。研究区δ13C值的分布相对均匀,除高于我国热带雨林区植物外,低于其它地区。研究结果还表明,种间碳同位素组成存在较大的差异。生境的变化对蕨的碳同位素组成影响较大,而对渐尖毛蕨、盐肤木、火棘、马桑影响较小。盐肤木、渐尖毛蕨、云南鼠刺、火棘叶片的δ13C值从生长初期到末期有降低的趋势,但降低的幅度存在差异。植物的δ13C值随小尺度海拔的变化规律与随大尺度海拔变化的规律一致,都是随着海拔的增加δ13C值增大,但不同植物种间变化的幅度是不一样的。     

环境因素对干旱-半干旱区城市银杏叶片碳同位素组成的影响

影响植物碳同位素组成的环境因素较多,在环境参数越复杂的地区控制因素则越多。城市环境相对于自然环境来说,不仅气象因素对植物同位素组成有较大的影响,而且,城市环境中人为因素如大气污染物、城市建筑等均可以影响植物的碳同位素组成。根据对兰州市校园中银杏（Ginkgo biloba）各向叶片生长期（四月至十月）的碳同位素组成分析,了解影响叶片同位素组成的环境参数特征,通过CANOCO统计分析确定各参数之间的相关性。分析表明,城市中大气污染物质量浓度的变化对植物同位素组成的影响较大（两者的相关性为r=0.550）,降水、光照、温度等也是影响植物碳同位素组成的重要因素。由于受到各个环境因素的综合影响,除有效湿度（两者的相关性为r=0.761）外,其它各种因素与叶片碳同位素组成之间的相关性并不强。而环境参数对植物叶片碳同位素组成影响主要由叶片气孔的开闭进行。