资阳市大气污染源排放清单研究

采用实地调研、资料收集等方式获得了2017年资阳市典型污染源的活动水平数据,参照城市大气污染物排放清单编制技术手册建立了基于排放因子法和物料衡算法的资阳市大气污染源排放清单,分析了主要污染物的行业排放特征和空间分布特征。结果表明,2017年资阳市SO₂、NO_X、CO、PM₁₀、PM_2.5、VOCs、NH₃总排放量分别为3.58kt、13.91kt、94.91kt、25.51kt、8.67kt、23.84kt和46.44kt。SO₂排放主要来自工业源;NOX排放主要来自移动源;CO排放主要来自工业过程及移动源;PM₁₀和PM_2.5、排放来自扬尘源和露天秸秆焚烧;VOCs主要来自溶剂使用源;NH₃主要来自农业活动。资阳市主要污染物排放分布在工业点源较为集中的雁江区和安岳县,乐至县污染物排放量相对较小。     

聚磷激酶基因在假单胞菌中的整合和表达

为了构建高效除磷的微生物,将来源于大肠杆菌的聚磷激酶基因(ppk)插入广宿主载体pBBR1MCS-2多克隆位点区,得到质粒pBBR1MCS-2-ppk.以该质粒为模板,通过PCR扩增出携带有载体启动子和终止子序列的ppk基因,插入自杀型质粒pUTmini-Tn5中得到重组质粒pUTmini-Tn5-ppk.pUTmini-Tn5-ppk经三亲接合作用进入Pseudomonas putidaKT2440,同时mini-Tn5通过转座作用将ppk整合到宿主菌株的染色体DNA中,获得基因工程菌Pseudomonas putidaKT2440-PPK,用于表达ppk.RT-PCR结果显示,ppk基因在KT2440-PPK中得到较高量的表达,而在原始菌株KT2440中表达微弱.人工模拟污水实验结果表明,接种1 h时KT2440-PPK中聚磷含量达到最大,为3.05 mg/g,约是对照菌株KT2440的15倍.测定模拟污水中磷酸盐的含量表明,KT2440-PPK可以去除该模拟污水中90%以上的磷酸盐.     

Ecological service assessment of human-dominated freshwater ecosystem with a case study in Yangzhou Prefecture, China

Freshwater ecosystems provide a host of services to humanity. These services are now rapidly being lost, not least because of the inability of making the impacts measurable. To overcome this obstacle, assessment frameworks for freshwater ecosystem services are needed. A simple water equivalent framework to assess the ecological services provided by freshwater ecosystems was developed in this study. It translated the occupation of freshwater ecosystem services into biologically freshwater volumes and then compares this consumption to the freshwater throughput, that is, the ecological capacity available in this region. In this way, we use the example of Yangzhou Prefecture, to account the main categories of human occupation of water ecosystem services. The result showed that there is a huge gap between the consumption and the supply of freshwater ecosystem services. This must encourage local government to make land-use and water management decisions both economically rational and environmentally sound.     

NOx和VOC自然源排放及其对中国地区对流层光化学特性影响的数值模拟研究

利用Williams等和Guenther等的模型估计中国地区NOx和VOC的自然源排放.所得清单显示土壤NOx排放总量(以N计)为225.75 Gg;植被VOC年排放总量(以C计)为13.23 Tg,其中异戊二烯、单萜烯、其它VOC分别为7.77、1.86、3.60 Tg;排放有明显季节变化和空间变化.运用中尺度气象模式MM5以及光化学模式Calgrid研究这些排放在不同季节对对流层化学的影响.结果表明,O3、NOx、HNO3和PAN的全国平均浓度在土壤NOx排放影响下分别增加15.3%、15.7%、25.5%和6.5%;在植被VOC排放影响下改变5.6%、-4.9%、-19.3%和142.3%;在两者综合影响下增加26.1%、8.8%、4.3%和177.9%;浓度变化在夏季明显强于其它季节.自然源对中国地区光化学污染物空间分布有不同程度的影响,这种影响同区域气象条件、源排放和NMHC/NOx比值等因素有关.NOx和VOC的自然源排放对光化学特性影响显著,在光化学模拟过程中不容忽视.     

灵庄港河道底泥化学组成及其环境影响初探

本文研究灵庄港待疏浚的底泥的养分特征及重金属污染物的化学组分,探讨该底泥处置方式及其可能带来的环境影响。结果表明：灵庄港疏浚底泥的养分含量高于河道两岸耕地耕作层土壤,底泥中重金属元素符合农用底泥污染物控制标准,可以直接投放到附近的农田以增加经济效益,节约处置费用。     

合成水滑石治理水体阴离子染料污染研究

利用不同层电荷的合成水滑石（层状双氢氧化物）和它们的焙烧态为吸附剂，系统考察了此类材料对于甲基橙染料的吸附保留行为，通过粉末X射线衍射，傅立叶红外和扫描电镜测试说明经水热处理得到的合成水滑石具有良好的结晶度和相纯度．水滑石及其焙烧态对于甲基橙阴离子染料的吸附研究主要采用间歇平衡法实验，吸附体系的电导率变化显示了水滑石的记忆效应，并有可能是焙烧态水滑石再生的动态过程反应低浓度甲基橙在焙烧态水滑石上的吸附实验说明，水滑石层电荷密度对于其焙烧态氧化物吸附低浓度阴离子具有显著的影响。     

青藏公路取土场高寒草原植被的恢复进程

按照青藏公路建设和整修的不同阶段,利用样方调查植被空间分布变化,得出高寒草原植被的自然演替进程遵循以下规律,在工程结束2年,8年,26年后,群落植被覆盖度和生物多样性指标分别达到原生植被的2%～4%,6%～23%;32%～54%,46%～50%;95%以上和100%左右.青藏公路沿线高寒草原植被的人为破坏影响是明显的,植被的自然恢复需要20年左右的时间.工程建设破坏面积大于1500m2,植被难以恢复,土壤沙化和水土流失,影响周边地区生态环境质量.因此,在青藏铁路工程建设中首先应当减少对地形地貌的破坏,其次应当重视对地表土壤的保护并辅助人工植被恢复措施,促进植被的自然恢复.     

Activity maintenance of the excised branches and a case study of NO2 exchange between the atmosphere and P. nigra branches

The efficient maintenance of the activity of excised branches is the powerful guarantee to accurately determine gas exchange flux between the detached branches of tall trees and the atmosphere. In this study, the net photosynthetic rate(NPR) of the excised branches and branches in situ were measured simultaneously by using two photosynthetic instruments to characterize the activity of the excised branches of Phyllostachys nigra. The ratio of normalized NPR of excised branches to NPR in situ was used to assess the photosynthetic activity of detached branches. Based on photosynthetic activity, an optimal hydroponics protocol for maintaining activity of excised P. nigra branches was presented:1/8 times the concentration of Gamborg B5 vitamin mixture with p H = 6. Under the best cultivation protocol, photosynthetic activity of excised P. nigra branches could be maintained more than 90% within 6 hr in the light intensity range of 200–2000 μmol/(m2·sec) and temperature range of 13.4–28.7°C. The nitrogen dioxide(NO2) flux differences between in situ and in vitro branches and the atmosphere were compared using double dynamic chambers.Based on the maintenance method of excised branches, the NO2 exchange flux between the excised P. nigra branches and the atmosphere(from-1.01 to-2.72 nmol/(m2·sec) was basically consistent with between the branches in situ and the atmosphere(from-1.12 to-3.16 nmol/(m2 sec)) within 6 hr. Therefore, this study provided a feasible protocol for in vitro measurement of gas exchange between tall trees and the atmosphere for a period of time.     

骆马湖表层水体中32种PPCPs类物质的污染水平、分布特征及风险评估

为评价骆马湖水体中药品和个人护理品(PPCPs)的污染水平、空间分布特征及生态风险,利用高效液相色谱-串联质谱测定了骆马湖水体中22个采样点的32种PPCPs.结果表明,骆马湖表层水体中共检出了23种PPCPs,总浓度范围为892~1 536 ng·L~(-1),其中浓度最高的为诺氟沙星(256~707 ng·L~(-1)),其次是酮洛芬(85~438 ng·L~(-1))、安赛蜜(101~290 ng·L~(-1))及萘普生(1.9~112 ng·L~(-1)).不同采样位点的PPCPs浓度存在一定的空间差异,呈现湖东北部地区较高,西南部地区较低的趋势.房亭河入湖口处PPCPs浓度较高,嶂山闸出湖口处浓度较低.对13种药物类PPCPs生态风险评价结果表明,诺氟沙星RQs为0.26~0.72,对于骆马湖水生生态系统表现为中风险,吉非罗齐在大部分采样点RQs0.01,表现为低风险,其余的化合物RQs0.01未表现出生态环境风险.采用简单叠加模型计算PPCPs的联合毒性风险熵范围为0.29~0.75,整体上看,骆马湖PPCPs对于水生生物表现出中风险.对6种PPCPs的人体健康风险结果表明,RQs均小于1,表明骆马湖PPCPs对人体健康无直接风险.     

上海南汇潮滩表层中多环芳烃分布特征及环境意义

利用ＧＣ／ＭＳ分析了上海南汇淤泥质潮滩６，８两月表层沉积物中有机污染物多环芳烃，结果表明，该区在６月和８月８潮滩中ＰＡＨ组化芘，苯并芘及黄蒽具有较高的含量，并且在ＰＡＨ总量中所占比重也产大，在潮滩沉积物中已呈明显富集的趋势。