东北典型黑土区讷谟尔河流域土地利用变化对沟蚀影响研究

论文以东北典型黑土区中的黑龙江省讷谟尔河流域作为研究区,以1965年的Corona 和2005年的SPOT5影像做为数据源,获取研究区1965和2005年的侵蚀沟分布数据;以地形图、Landsat/MSS影像和TM影像作为数据源,获取1954、1975、1995和2005年的土地利用数据,据此就研究区沟蚀动态和土地利用变化对沟蚀发展的影响进行分析。结果表明：40 a间侵蚀沟密度>250 m/km²的区域由1965年的0 km²增加到4 077.17 km²,占总侵蚀区面积的37.57%;侵蚀沟密度以北东—南西向为轴线从剧烈增加区逐渐过渡到微度增加区;耕地上沟蚀状况最严重,草地和沼泽地次之,林地侵蚀沟密度较小;耕地和草地之间的互相转换,侵蚀沟密度增加最大,分别为600.60和456.08 m/km²;其次是林地转变为耕地,侵蚀沟密度增加346.91 m/km²;各沟蚀变化区耕地的增加比例在29.21%~46.54%之间,草地减少的比例在27.10%~41.50%之间,沼泽地减少的比例在5.86%~12.50%之间。     

东北典型湖库水体对铜绿微囊藻荧光特性的影响

为考察东北典型湖库水体对铜绿微囊藻(Microcystic aeruginosa)生长过程中IDOM(细胞内溶解性有机物)荧光特性的影响,在镜泊湖、兴凯湖、五大连池、松花湖和大伙房水库5个典型湖库,共10个采样点采集水样,用于铜绿微囊藻的培养,利用EEM(三维荧光光谱)技术,结合三维荧光FRI(区域体积积分)开展IDOM荧光特性的聚类分析. 结果表明:铜绿微囊藻中IDOM的主要荧光特征峰为类蛋白荧光峰(峰S和峰T),峰S荧光强度高于峰T;对IDOM的三维荧光光谱分为5个区(Ⅰ～Ⅴ区)进行区域体积积分,荧光响应值比例(P_Ⅰ+Ⅱ,n和P_Ⅳ,n)总体上呈互补趋势;Ф_T,n(总区域体积积分)表现为镜泊湖>五大连池>兴凯湖>松花湖>大伙房水库,第16天镜泊湖的Ф_T,n最大,平均值为9.76×10-5 AU·nm2/(mg/L);大伙房水库的Ф_T,n最小,平均值为3.72×10-5 AU·nm2/(mg/L). 聚类分析将10个采样点分成3类. HJ1、HJ2采样点为类别1;HX1、LD1、JS1、LD2采样点为类别2;HX2、JS2、HW2、HW1采样点为类别3,其中,类别1(镜泊湖)水体较类别2和类别3水体更适宜铜绿微囊藻的生长.      

四溴联苯醚(BDE-47)对两种海洋桡足类动物的毒性效应

为了研究四溴联苯醚(BDE-47)对海洋桡足类的毒性效应,以太平洋真宽水蚤和日本虎斑猛水蚤为受试生物,依据急性毒性实验96 h-LC₅₀值,设置5个浓度组和1个对照组,测定摄食率、滤水率、耗氧率、排氨率和抗氧化防御系统中SOD、GST、GPx活性以及GSH含量。结果显示：BDE-47对太平洋真宽水蚤和日本虎斑猛水蚤的96 h-LC₅₀分别为
57和851 μg·L^-1,后者明显高于前者。2种桡足类在BDE-47作用下,其能量摄入和代谢均受到不同程度的诱导或抑制。太平洋真宽水蚤在中浓度(1.425 μg·L^-1)下摄食率和排氨率受到促进,高浓度(5.70和11.40 μg·L^-1)下耗氧率明显抑制;日本虎斑猛水蚤高浓度下(170.20 μg·L^-1)摄食率受到抑制,中浓度(21.28 μg·L^-1)下耗氧率受到促进,各个浓度的BDE-47对其排氨率均有明显促进作用。太平洋真宽水蚤SOD活性在BDE-47暴露96 h过程中均低于对照组(P<0.05),受到明显抑制;GST活性随暴露时间延长先升高后降低;GSH含量和GPx活性低浓度(0.7125和1.425 μg·L^-1)下随时间先升高后降低,而高浓度(5.70和11.40 μg·L^-1)下则相反。日本虎斑猛水蚤SOD活性随BDE-47浓度的升高先降低后升高再降低;GST活性和GSH含量在低浓度(10.64和21.28 μg·L^-1)BDE-47中与对照组相比无显著差异(P>0.05),而高浓度(85.10和170.20 μg·L^-1)
BDE-47下,GST活性随时间先升高后降低,GSH含量则先降低后升高再降低;GPx活性呈现先降低后升高趋势。由此可见,BDE-47与这2种桡足类的能量摄入、代谢和抗氧化防御系统存在一定时间及剂量效应,并具有明显的物种差异性。     

东北北部温带森林和干草地土壤养分分布及影响因素

土壤是陆地生态系统碳储存的重要场所,其养分变化与全球陆地碳循环密切相关。土壤养分是植物生长的重要保证,而土壤各养分之间是紧密联系的。理解土壤养分变化与环境因素的关系有助于更好地了解陆地生态系统碳、氮、磷循环。本研究以东北北部自东向西沿降水量梯度变化纬度带上的温带森林与干草地生态系统为研究对象,利用气象数据和野外土壤实测数据,分析了纬度带上不同植被类型土壤的有机碳、全氮、碳氮比、速效磷的空间分布格局及其与环境因子（年降水量、年均温、土壤pH值）的关系。研究纬度带上降水量自东向西逐渐减少,植被类型从温带森林过渡到干草原,与降水量和植被类型对应,植被生物量也自东向西呈现从高到低的分布梯度。研究结果表明：从整个研究带上来说,降水量与土壤pH值是土壤养分空间分布的决定因素,沿纬度带从东到西,随着降水量逐渐减少,土壤pH值逐渐增加,而土壤有机碳、全氮、碳氮比、速效磷含量逐渐减少。但如果将森林和草地分别讨论则发现,森林和草地生态系统的土壤养分环境控制因素有较大差别。对于草地生态系统而言,降水量和土壤pH值仍然是其土壤养分含量的控制因子,但森林生态系统由于所处区域降水量充足,降水量不再是其土壤养分的控制因子,降水量只与森林土壤碳氮比呈显著正相关。研究还发现森林土壤的速效磷含量与温度呈正相关,与土壤pH值呈负相关,说明温度对东北北部温带森林的土壤养分含量具有一定的控制作用。     

环保督查中心执法难的对策研究

为了贯彻落实建立"国家监察、地方监管、单位负责"环境监管体制的要求,根据中编办的批复,国家环境保护总局设立了华南、华东、东北、西北和西南五大环境保护督查中心.     

Pollution characteristics and health risk assessment of benzene homologues in ambient air in the northeastern urban area of Beijing, China

Ambient benzene homologues were measured at a site in the northeastern urban area of Beijing, China, from August 24 to September 4, 2012 by SUMMA canister sampling followed by laboratory determination using cryogenic cold trap pre-concentration-GC-MS/FID, and their health risks were also assessed. Daily total benzene homologues ranged from 0.99 to 49.71 μg/m3with an average of 11.98 μg/m3. Benzene homologues showed higher concentrations in the morning and evening than that at noontime. Comparison with previous studies revealed a trend of decrease for ambient benzene homologues probably due to the efective emission control in Beijing in recent years. Vehicular exhaust was the main source while volatilization of paints and solvents also made substantial contributions. Health risk assessment showed that BTEX(benzene, toluene, ethylbenzene, o-xylene, m-xylene and p-xylene) and styrene had no appreciable adverse non-cancer health risks for the exposed population, while benzene has potential cancer risk of 1.34E-05. Available data from cities in China all implied that benzene imposes relatively higher cancer risk on the exposed populations and therefore strict control measures should be taken to further lower ambient benzene levels in China.     

Effects of elevated CO2 concentration and nitrogen supply on biomass and active carbon of freshwater marsh after two growing seasons in Sanjiang Plain, Northeast China

An experiments were carried out with treatments differing in nitrogen supply (0, 5 and 15 g N/m²) and CO₂ levels (350 and 700 μmol/mol) using OTC (open top chamber) equipment to investigate the biomass of Calamagrostis angustifolia and soil active carbon contents after two years. The results showed that elevated CO₂ concentration increased the biomass of C. angustifolia and the magnitude of response varied with each growth period. Elevated CO₂ concentration has increased aboveground biomass by 16.7% and 17.6% during the jointing and heading periods and only 3.5% and 9.4% during dough and maturity periods. The increases in belowground biomass due to CO₂ elevation was 26.5%, 34.0% and 28.7% during the heading, dough and maturity periods, respectively. The responses of biomass to enhanced CO₂ concentrations are differed in N levels. Both the increase of aboveground biomass and belowground biomass were greater under high level of N supply (15 g N/m²). Elevated CO₂ concentration also increased the allocation of biomass and carbon in root. Under elevated CO₂ concentration, the average values of active carbon tended to increase. The increases of soil active soil contents followed the sequence of microbial biomass carbon (10.6%) > dissolved organic carbon (7.5%) > labile oxidable carbon (6.6%) > carbohydrate carbon (4.1%). Stepwise regressions indicated there were significant correlations between the soil active carbon contents and plant biomass. Particularly, microbial biomass carbon, labile oxidable carbon and carbohydrate carbon were found to be correlated with belowground biomass, while dissolved organic carbon has correlation with aboveground biomass. Therefore, increased biomass was regarded as the main driving force for the increase in soil active organic carbon under elevated CO₂ concentration.     

向烧烤炉中添酒精烧人更烧心

<正>大学时光本是人生最美好的时刻,然而由于这次意外,她的人生轨迹发生了巨大转变,或许再也无法重返校园。现在再去后悔已毫无意义,悲剧过后,更需反思。烧烤店这样一种行业,明火比较多,隐患无所不在,安全、防范意识应该比其他店铺高才对。对店员的培训应该更具体、更详细,添加酒精更是烧烤店必不可少的,也是安全隐患较大的,烧烤店应该额外注意,多次强调。还要准备更加充分的灭火器材,这样才能保证顾客,还有店     

中国东北、内蒙古地区茶藨属果树资源的研究

本文对东北、内蒙古地区茶属果树资源进行了调查，初步查明有１９种、２变种、１变型，并对其特征、特性、生境、分布及利用价值进行了研究，总结了驯化栽培的研究结果，提出了开发利用的建议。     

东北农村住宅低碳集成技术应用大有可为

近年来,我国东北寒冷地区研究开发出的苯板、稻草板、稻草砖等节能材料已在农村节能住房建设中得到推广应用,并不断规范化和完善,现已应用到双层建筑和不同框架结构的农村建筑中。目前,草砖节能住宅建筑技术已在黑龙江大庆市林甸县、