底物和电子受体对互花米草湿地沉积物甲烷产生潜力的影响

采用室内厌氧培养法研究闽江河口潮汐盐湿地甲烷产生不同底物(醋酸、甲醇和三甲胺)及电子受体(SO42-、NO3-和NH4+)对外来入侵种互花米草Spartinaalterniflora湿地表层沉积物甲烷产生潜力的影响,结果表明:盐湿地非竞争性甲烷产生底物中的甲醇对互花米草湿地表层沉积物甲烷产生潜力的促进作用最大,高于醋酸和三甲胺,且3种底物的添加均在培养5d后对沉积物甲烷产生潜力的促进作用最为明显;随着培养时间的增加,不同浓度的SO42-、NO3-、NH4+的添加对沉积物甲烷产生潜力的影响呈现出抑制作用或无抑制作用2种结果,添加电子受体的浓度越高,对沉积物甲烷产生潜力的抑制作用越显著。     

热分解法测定水盐体系中硝酸铵和水含量研究

针对复杂硝酸铵水盐体系溶解度的测定,传统分析方法操作步骤繁琐,且试剂较贵,引入一种简单准确的分析方法,即热分解法,对LiNO3-KNO3-NH4NO3-H2O体系和NaNO3-KNO3-NH4NO3-H2O体系中硝酸铵和水的含量进行精确分析。结果表明,热分解温度控制在230～240℃,若控制样品质量为1.5 g,分解时间不低于36 h,能将LiNO3-KNO3-NH4NO3-H2O体系中的硝酸铵和水彻底分解,且随着样品中硝酸铵含量增加,热分解时间也将延长,分析相对误差能控制在0.2%以内。针对复杂NaNO3-KNO3-NH4NO3-H2O体系,热分解温度控制在230～255℃,若控制样品质量为1.5 g,分解时间不少于44 h,且随着样品中硝酸铵含量的增加,相应延长热分解时间,能将复杂NaNO3-KNO3-NH4NO3-H2O体系中的硝酸铵和水彻底分解,分析相对误差能控制在0.2%以内。     

中国第26次南极科学考察航线上空水溶性气溶胶化学成分特征研究

利用我国第26次南极考察航线上所采集到的气溶胶样品,分析了各水溶性离子组分的浓度、组成及存在形式.采用多种数理统计方法对各离子成分特征及其来源进行了分析.结果显示:阴阳离子总和接近于1,表明航线上空主要阴阳离子具有海洋气溶胶的代表性;CI-、Na<'+>、SO<'2-><,4>、NO<'-><,3>、Mg<'2+>是航...     

Spatial variability of chemical tracers in surface snow along the traverse route from the coast to 1000 km inland at east Dronning Maud Land, Antarctica

We measured the spatial variability of Cl -, Na +, SO 2- 4, NO - 3 and 7Be concentrations in snow cover along the traverse route from S16 to Dome Fuji station in east Dronning Maud Land, Antarctica. The concentrations of Cl - and Na + at the coast exponentially decreased with distance from the coast up to 200 km inland. Between 200 1000 km inland, the concentrations of Na + were nearly constant. On the other hand, the concentrations of Cl - increased with distance beyond 750 km inland. Furthermore, the contribution factors between Cl - and Na + decreased and the Cl -/Na + ratio and the nssCl -/Cl - ratio increased toward the interior of the continent. These results indicate that sea salt aerosols are transported from the coastal region toward the inland region of the Antarctic continent, and that a source of Cl - other than sea salt exists in the inland plateau of Antarctica. The concentrations of SO 2- 4, NO - 3 and 7Be in snow were relatively high in the coastal region and the inland plateau region compared with those in the katabatic wind region.     

不同年龄杉木人工林土壤无机氮比较研究

在福建南平杉木林中心产区,选取11、21、28、40、88年生杉木人工林以及采伐迹地、杂木林为研究对象,研究不同年龄杉木林土壤无机氮的差异．结果表明：不同年龄杉木林土壤NH4^＋-N含量差异显著,以21年生的杉木人工林最高（11．91±0．43mg·kg^-1）,其他的为88年生的（8．33±0．38mg·kg^-1）〉28年生的（8．19±0．25mg·kg^-1）〉11年生的（5．65±0．17mg·kg^-1）〉40年生的（5．63±0．38mg·kg^-1）;NO3^--N含量较低（3．15～4．11mg·kg^-1）,且没有显著差异,这与杉木林所处的生长阶段、土壤理化性质有关．杉木林取代杂木林后,NH4^＋-N和NO3^--N含量都有所下降;采伐迹地土壤NH4^＋-N（19．74±1．44mg·kg^-1）和NO3^--N（18．05±0．72mg·kg^-1）含量远高于88年生的杉木林,分别是88年生的2．37和4．60倍．本地区无机氮含量较低,NH4^＋-N占无机氮的比例为60．0％～74．3％,NH4^＋-N为无机氮的主要形态．     

Characteristics of ion concentrations in snowpits in Longyearbyen, Svalbard, Arctic

１ＩｎｔｒｏｄｕｃｔｉｏｎＳｔｕｄｉｅｓｏｎｃｈｅｍｉｃａｌｃｈａｒａｃｔｅｒｉｓｔｉｃｓｉｎｓｎｏｗｐｉｔａｒｅｖｅｒｙｉｍｐｏｒｔａｎｔｉｎｒｅｓｅａｒｃｈｏｆｍｏｄｅｒｎｐｒｏｃｅｓｅｓｉｎｓｎｏｗａｎｄｉｃｅ,ｗｈｉｃｈｉｓｂａｓｉｃｃｏｎｔ...     

天山乌鲁木齐河源1号冰川大气气溶胶和新雪中可溶性离子关系研究

在2007年4月、8月和10月三个时段内,分昼夜采集了23个气溶胶样品和7个新降雪样品,对样品中的可溶性离子进行了分析。结果表明,乌鲁木齐河源1号冰川(以下简称1号冰川)春、夏、秋三个季节气溶胶平均载量为86.22 neq/m³,分析显示1号冰川存在NH₄HSO₄和(NH₄)₂SO₄气溶胶,并有少量NH₄NO₃气溶胶存在。气溶胶和新雪样品中可溶性离子成分变化趋势相似,气溶胶浓度升高,新雪样品的浓度也会有所升高,反之亦然。气溶胶和新雪中Ca²⁺、Mg²⁺、Na⁺、Cl^-、K⁺的相关性很好,说明雪中这些离子的浓度基本能反映大气中的状况;对气相和颗粒相并存的NH₄⁺和NO₃^-来说,雪中的离子浓度和大气中的离子浓度不相关。     

聚丙烯中空纤维膜分离混合气中氨的研究

以Ｈ２ＳＯ４溶液为吸收液，用聚丙稀中空纤维研究了Ｎ２、ＮＨ３混合气中分离氨的传质过程．该过程中，氨的分离为一级动力学过程，Ｈ２ＳＯ４和（ＮＨ４）２ＳＯ４浓度对氨的分离没有明显影响．实验结果表明，Ｈ２ＳＯ４的平均利用率为９９％以上，（ＮＨ４）２ＳＯ４的生产能力为１４７．７ｋｇ／ｍ２·ｄ．     

北极Svalbard群岛Longyearbyen地区雪坑主要阴、阳离子特征研究

北极Ｓｖａｌｂａｒｄ群岛Ｌｏｎｇｙｅａｒｂｙｅｎ地区３条冰川８个雪坑样品的分析结果表明,该地区冰川表层雪中海盐离子Ｃｌ－和Ｎａ＋占主导地位,其浓度远高于其它离子,而陆源Ｃａ２＋在雪坑秋季污化层中浓度远远高于其它层位,可作为雪坑定年中秋季层位的标志。在季节变化上,海盐离子和ＳＯ２－４、ＮＯ－３在春季和夏季表现为高值,这与冬春季节北大西洋风暴和中纬度人类污染物远距离传输到北极有关,也与夏季局地海洋性气团、大气中氧化作用、光电作用和清除速率有关。同全球的边远地区格陵兰、南极和青藏高原比较,Ｌｏｎｇｙｅａｒｂｙｅｎ地区雪中离子浓度水平较高,特别是海盐离子浓度远高于其它地区。     

降水变化对中国南方强酸雨分布的影响

Acid rain has been recognized as a serious environmental problem in China since the 1980s, but little is known about the effects of the climatic change in regional precipitation on the temporal and spatial variability of severe acid rain. We present the effects of the re-gional precipitation trend change on the area and intensity of severe acid rain in southern China, and the spatio-temporal distribution characteristics of SO2 and NO2 concentrations are analyzed on the basis of SO2 and NO2 column concentration data. The results are as follows. (1) The emission levels of SO2 and NO2 have reached or passed the precipitation scavenging capacity in parts of southern China owing to the emission totals of SO2 and NO2 increasing from 1993 to 2004. (2) Notable changes in the proportion of cities subject to severe acid rain occurred mainly in the south of the middle-lower reaches of the Yangtze River during 1993-2004. With an abrupt change in 1999, the severe acid rain regions were mainly located in central and western China during 1993-1999 and moved obviously eastward to the south of the lower-middle reaches of the Yangtze River with the proportion of cities subject to se-vere acid rain increasing significantly from 2000 to 2004. (3) The spatial distribution and variation in the seasonal precipitation change rate of more than 10 mm/10a are similar to those of severe acid rain in southern China. An abrupt change in 1999 is seen for winter and summer precipitation, the same as for the proportion of cities subject to severe acid rain in southern China. The significant increase in summer storm precipitation from 1991 to 1999 mitigated the annual precipitation acidity in the south of the Yangtze River and reduced the area of severe acid rainfall. On the other hand, the decrease in storm rainfall in summer ex-panded the area of severe acid rainfall in the south of the Yangtze River in 2000-2006. Therefore, the change in seasonal precipitation is an important factor in the severe acid rain regions moving eastward and expanding in southern China.     

Effects of precipitation variation on severe acid rain in southern China

Acid rain has been recognized as a serious environmental problem in China since the 1980s,but little is known about the effects of the climatic change in regional precipitation on the temporal and spatial variability of severe acid rain.We present the effects of the regional precipitation trend change on the area and intensity of severe acid rain in southern China,and the spatio-temporal distribution characteristics of SO2 and NO2 concentrations are analyzed on the basis of SO2 and NO2 column concentration data.The results are as follows.(1) The emission levels of SO2 and NO2 have reached or passed the precipitation scavenging capacity in parts of southern China owing to the emission totals of SO2 and NO2 increasing from 1993 to 2004.(2) Notable changes in the proportion of cities subject to severe acid rain occurred mainly in the south of the middle-lower reaches of the Yangtze River during 1993-2004.With an abrupt change in 1999,the severe acid rain regions were mainly located in central and western China during 1993-1999 and moved obviously eastward to the south of the lower-middle reaches of the Yangtze River with the proportion of cities subject to severe acid rain increasing significantly from 2000 to 2004.(3) The spatial distribution and variation in the seasonal precipitation change rate of more than 10 mm/10a are similar to those of severe acid rain in southern China.An abrupt change in 1999 is seen for winter and summer precipitation,the same as for the proportion of cities subject to severe acid rain in southern China.The significant increase in summer storm precipitation from 1991 to 1999 mitigated the annual precipitation acidity in the south of the Yangtze River and reduced the area of severe acid rainfall.On the other hand,the decrease in storm rainfall in summer expanded the area of severe acid rainfall in the south of the Yangtze River in 2000-2006.Therefore,the change in seasonal precipitation is an important factor in the severe acid rain regions moving eastward and expanding in southern China.     

南极中山站近岸海冰生态学研究 Ⅳ.海冰营养盐浓度的季节变化及其与生物量的关系

对１９９２年４月至１２月间中山站近岸海冰营养盐状况以及与生物量的关系进行了分析。为了能与海水中的营养盐进行对比,对海冰融化样的营养盐数据进行了同期冰下海水表层盐度的校正。结果显示,海冰中多数层次的硝酸盐浓度低于冰下表层海水的浓度,而磷酸盐和硅酸盐浓度则正好相反,亚硝酸盐浓度在观测期间均高于冰下表层海水的浓度。海冰营养盐浓度无明显的变化规律,呈现较大的波动,它可以是冰下表层海水的数分之一直至高出一个数量级,除显著的冰底水华期外并不构成冰藻生长的限制因素。海冰营养盐的分布与叶绿素ａ含量无明显的相关性。     

Li2SO4溶液中离子间的缔合相互作用:基于密度泛函理论和分子动力学模拟的研究

基于密度泛函理论,使用B3LYP/aVDZ方法对[Li_2SO_4(H_2O)_n]~0(n=0~10、18)水合团簇的结构和性质进行了系统地研究,并结合Car-Parrinello分子动力学(CPMD)模拟了不同浓度的Li_2SO_4溶液结构,目的在于理解在Li_2SO_4溶液中离子间缔合相互作用及可能存在的物种。研究发现,对于[Li_2SO_4(H_2O)_n]~0(n=0~10、18)水合团簇,双配位单齿螯合接触离子对结构比双配位双齿螯合接触离子对结构更稳定,溶剂共享离子对结构最不稳定。同时,CPMD模拟结果表明,在3.09和3.17 mol/kg的Li_2SO_4溶液中,双配位单齿螯合接触离子对结构仍然是主要物种。以上结果表明在饱和的Li_2SO_4溶液(3.16 mol/kg)中,Li~+和SO_4~(2-)离子间的相互缔合作用主要以双配位单齿螯合接触离子对结构的物种存在,而具有双配位双齿螯合离子对结构的物种占少数,溶剂共享离子对结构几乎不存在。     

极地冰雪环境地球化学指标及其指示意义

极地冰雪中可以反映气候环境的环境地球化学指标主要是可溶性杂质和不可溶性微粒。可溶性杂质主要包括H+、Na+、Mg2 +、Ca2 +、NH4+、Cl- 、NO3- 、SO42 - 、CH3SO3- 等。本文在概述冰雪中的这些化学杂质的来源影响因素和时空分布特征的基础上 ,概述了冰雪中NO3- 沉积的主要来源 (即闪电作用和高层大气光化学作用产生的含氮化合物等 )及其影响因素 (包括太阳活动、火山活动、超新星活动、核爆炸试验和沉积后的蒸发及迁移作用等 ) ,SO42 - 的主要来源 (即海洋生物释放和火山喷发等 )、影响因素 (包括源区温度、ENSO事件及海冰面积等 )和它们的时空变化特点 ;讨论了南、北极地区冰雪中微粒沉积的主要源区和变化特征。。     

南极菲尔德斯半岛地区与拉斯曼丘陵地区湖泊水化学比较研究

为了解南极淡水生态系统的水化学特征，完成了拉斯曼丘陵地区１３个湖泊和菲尔德斯半岛１０个湖泊以及雪样的调查分析。西南极乔治王岛菲尔德斯半岛和东南极拉斯曼丘陵的气候条件不同，前者属于极地海洋性气候、气温不很低、湿润、风小、夏季较长；后者属于极地大陆性气候、气温低，冬天严寒、干燥、风大，夏季较短。因此，两地区的湖泊地貌、成因、发育、水生生物种群结构以及水化学状态存在较明显的差异，虽然水化学类型均比较单一，但矿化度却相差甚大。本文还对两区饮水水源进行了评价。     

典型岩溶农业区地下水质与土地利用变化分析--以云南小江流域为例

以云南省泸西县小江典型岩溶农业流域为研究单元,利用1982和2004的地下水质数据及1982的航片和2004年的TM影像,在GIS支持下,研究其20年来的地下水质的时空变化及原因。结果表明：20年来流域地下水质在时间、空间分布上均发生较大的变化;流域耕地扩张和大量化肥、农药使用带来的非点源污染,造成地下水中的NH₄⁺、SO₄^2-、NO₃^-、NO₂^-、Cl^- 离子含量及pH值、总硬度、总碱度明显升高并超标,而林地减少或林地质量的下降,土地发生石漠化时,地下水中的Ca²⁺、HCO₃^- 浓度明显降低,同时,地下水各指标的空间变化与土地利用空间格局的变化表现出动态一致性。     

于桥水库流域地表水非点源N时空变化特征

在野外水样监测（1999年5月－2000年10月）和土地利用调查的基础上，利用遥感影像和数字化地形图，运用GIS的空间分析和图形叠置功能，研究于桥水库域地表水非点源N的时空变化特征。结果表明，在时间上，NH4^ －N的峰值出现在枯水期，而NO3^-N的峰值出现在丰水期；在空间上，NH4^ －N含量在中部平原区最高，南部丘陵和北部山区居其次，NO3^-N含量的变化则不具有明显的规律性。NH4^ －N和NO3^-不同的时空分布特征与它们的化学性质及流域内土地利用格局有关。     

Groundwater quality and land use change in a typical karst agricultural region: a case study of Xiaojiang watershed, Yunnan

Taking the typical karst agricultural region, Xiaojiang watershed in Luxi of Yunnan Province as a research unit, utilizing the groundwater quality data in 1982 and 2004, the aerial photos in 1982 and TM images in 2004, supported by the GIS, we probe into the law and the reason of its space-time change of the groundwater quality over the past 22 years in the paper. The results show: (1) There were obvious temporal and spatial changes of groundwater quality during the past 22 years. (2) Concentrations of,SO42-,NO3-,NO2-,Cl-,and the pH value, total hardness, total alkalinity increased significantly, in which NH4+,NO3-, and NO2- of groundwater exceeded the drinking water standards as a result of non-point pollution caused by the expansion of cultivated land and mass use of the fertilizer and pesticide. (3) Oppositely, Ca2+ and HCO3- showed an obvious decline trend due to forest reduction and degradation and stony desertification. Meantime, there was a dynamic relation between the groundwater quality change and the land use change.     

中亚热带2种天然林表层土壤N2O排放速率

运用静态箱-气相色谱法对中亚热带地区米槠天然林和阿丁枫天然林土壤N2O排放速率进行了1年（2012年1月—2013年1月）原位观测,分析了土壤温度及含水量对土壤N2O排放速率的影响,并探讨土壤无机N含量变化与土壤N2O排放速率的关系。结果表明,观测期间,2种天然林均表现为大气N2O排放源,米槠天然林和阿丁枫天然林平均土壤N2O排放速率分别为7.29μg·m^-2·h^-1、7.41μg·m^-2·h^-1;米槠天然林和阿丁枫天然林土壤N2O排放速率季节变化明显,最高排放速率均出现在夏季6月,分别为16.51μg·m^-2·h^-1、18.86μg·m^-2·h^-1;2个林分N2O排放速率最低值分别出现在2012年1月和2012年9月,分别为3.04μg·m^-2·h^-1和2.17μg·m^-2·h^-1。2种天然林土壤N2O排放速率均与土壤温度无显著相关性,与土壤含水量显著正相关（P〈0.05）;2种天然林土壤N2O排放速率与NH4＋含量均无显著相关性,米槠天然林和阿丁枫天然土壤N2O排放速率与NO3-含量分别呈显著负相关和显著正相关（P〈0.05）。研究结果表明,土壤含水量及NO3-含量的变化对中亚热带天然林土壤N2O排放速率有着重要的影响。     

2013 年春季华南师范大学石牌校区大气冷凝水的化学特征与来源

通过人工制冷的方法收集2013 年华南师范大学石牌校区大气冷凝水52 个样品,对其进行pH 值和阴阳离子分析。结果表明：2013 年春季石牌校区绝大多数冷凝水样品的pH 值分布范围为5.00~6.47,平均值为5.97,已不属于酸雨。冷凝水的阴阳离子总质量浓度（TDS）介于57.87~484.38 μeq/L 之间,平均值为154.53 μeq/L;各离子质量浓度高低依次为2-4 SO ＞Ca2+＞ -3 NO ＞Na+＞Cl-＞NO2-＞Mg2+≈K+＞F-。石牌校区冷凝水的这种离子质量浓度分布特征显示：其清洁程度较优于2011 年春季该校区和同期上海大气冷凝水,而较差于云南丽江的大气降水,与广东鹤山和青海瓦里关山等地的大气降水相当。其污染来源除部分属自然源外,还主要与建筑活动、工业生产、汽车尾气等人类活动等有密切关系。