Chemical compositions and radiative properties of dust and anthropogenic air masses study in Taipei Basin, Taiwan, during spring of 2004

Asia is one of the major sources of not only mineral dust but also anthropogenic aerosols. Continental air masses associated with the East Asian winter monsoon always contain high contents of mineral dust and anthropogenic species and transported southeastward to Taiwan, which have significant influences on global atmospheric radiation transfer directly by scattering and absorbing solar radiation in each spring. However, few measurements for the long-range transported aerosol and its optical properties were announced in this area, between the Western Pacific and the southeastern coast of Mainland China. The overall objective of this work is to quantify the optical characteristics of different aerosol types in the Eastern Asian. In order to achieve this objective, meteorological parameters, concentrations of PM₁₀ and its soluble species, and optical property of atmospheric scattering coefficients were measured continuously with 1 h time-resolved from 11 February to 7 April 2004 in Taipei Basin (25°00′N, 121°32′E). In this work, the dramatic changes of meteorological parameters such as temperature and winds were used to determine the influenced period of each air mass. Continental, strong continental, marine, and stagnant air masses defined by the back-trajectory analysis and local meteorology were further characterized as long-range transport pollution, dust, clean marine, and local pollution aerosols, respectively, according to the diagnostic ratios. The aerosol mass scattering efficiency of continental pollution, dust, clean marine, and local pollution aerosols were ranged from 1.3 to 1.6, 0.7 to 1.0, 1.4 and 1.4 to 2.3 m² g⁻¹, respectively. Overall, there are two distinct populations of aerosol mass scattering efficiencies, one for an aerosol chemical composition dominated by dust (<1.0 m² g⁻¹) and the other for an aerosol chemical composition dominated by anthropogenic pollutants (1.3–2.3 m² g⁻¹), which were similar to the previous measurements with high degree of temporal resolution.     

预制床法生物修复胜利油田含油污泥的研究

针对胜利油田滨一污水站产生的含油污泥,建立了面积2400 m2的预制床处理工程,使用石油降解菌菌剂对含油量为110 160mg(以每千克烘干含油污泥计)的污泥进行了生物修复,经过160 d的处理后,含油污泥中石油降解率可达52.75%.针对北方冬季低温的特点,在处理场中建立了温室保温措施.温室内外修复效果的比较表明,在冬季采取适当的保温措施可以明显提高污泥中石油烃类的降解率.     

“双杂”间作稻在开发冬水田中的效果

四川省中稻→冬水田近2000万亩,集中分布于盆地丘陵区,资源丰富。为发挥它的增产潜力,将中稻改为“双杂”间作稻,增产极显著。其中威优49间汕优63,双行间作,早稻科距8cm、窄行15cm、宽行49cm 中嵌插2行晚稻的小区,亩产728.0～776.9kg,比同田毗邻的汕优63中稻增产31.4%～45.0%,增加纯收入56.46元,为丘陵区中稻→冬水田的合理利用开辟了一条很好的途径。     

Numerical experiments for the impacts of temperature and precipitation variation on the growth and development of winter wheat

The growth process of winter wheat was simulated by CERES-wheat model assuming the daily temperature increase -1, 0,1, 2℃ and daily precipitation increase -20, -10, -5, 0, 5, 10, and 20 percent, respectively. The case study site is Zhenjiang City of Jiangsu Province in the east China. Simulation results show that the impacts of temperature variation on winter wheat is stronger than that of precipitation. Climate warming would speed development rate and shorten phonological period. In general, the adverse effect of climate change on grain yield is greater than that of its beneficial effect, especially when the climate becoming cooler and dryer. The increase of temperature and decrease of precipitation would reduce the plant extractablc soil water content.     

Differences of cadmium absorption and accumulation in selected vegetable crops

ＩｎｔｒｏｄｕｃｔｉｏｎＣａｄｍｉｕｍｉｓｐｒｉｎｃｉｐａｌｌｙｄｉｓｐｅｒｓｅｄｉｎｎａｔｕｒａｌａｎｄａｇｒｉｃｕｌｔｕｒａｌｅｎｖｉｒｏｎｍｅｎｔｓｔｈｒｏｕｇｈｖａｒｉｏｕｓａｇｒｉｃｕｌｔｕｒａｌ,ｍｉｎｉｎｇａｎｄｉｎｄｕｓｔｒｉａｌａｃｔｉｖｉｔｉｅｓａｓｗｅｌｌａｓｒｅｓｕｌｔｉｎｇｆｒｏｍｔｈｅｅｘｈａｕｓｔｇａｓｅｓｏｆａｕｔｏｍｏｂｉｌｅｓ(Ｄａｓ,1 997) .Ｔｈｉｓｔｒａｃｅｍｅｔａｌｉｓｔｈｅｐｏｌｌｕｔａｎｔａｎｄｐｏｔｅｎｔｉａｌｔｏｘｉｎｔｈａｔｈａｓｕｎｋｎｏｗｎｆ…     

Contribution of winter fluxes to the annual CH4, CO2 and N2O emissions from freshwater marshes in the Sanjiang Plain

Introduction C arbon dioxide, m ethane and nitrous oxide play im portant roles in the radiation balance of the earth contributing to the greenhouse effect (Rodhe, 1990). N 2O also takes part in the destruction of stratospheric ozone (W ang, 1999). N atura…     

浅层咸水灌溉对冬小麦和土壤安全性的研究

主要研究利用浅层地下咸水灌溉冬小麦及土壤的安全性。试验采取3因素多水平组合设计,利用2.5~6.0g·L-1不同矿化度咸水对冬小麦进行灌溉。试验结果表明:冬小麦产量与咸水矿化度呈负相关关系r=-0.8542、r=-0.8457,与咸水灌溉量呈正相关关系r=0.7487、r=0.7401。利用小于4.0g·L-1咸水灌溉对土壤具有一定的脱盐作用,咸水矿化度为6.0g·L-1时土壤中的盐分积累达到85.5%。矿化度5.0g·L-1以上的咸水不宜直接灌溉农田,需经淡水与咸水调配后,矿化度在4.0g·L-1以下方可灌溉农田。     

盘锦市冬季PM2.5水溶性离子特征及来源分析

为探讨盘锦市冬季PM_(2.5)水溶性离子污染特征和来源,于2017年1月采集3个点位的PM_(2.5)样品,用ICS-900离子色谱仪分析了8种离子(Na~+、Mg~(2+)、Ca~(2+)、K~+、NH_4~+、SO_4~(2-)、Cl~-和NO_3~-).开展了PM_(2.5)和离子浓度特征分析、硫氧化率(SOR)和氮氧化率(NOR)计算、离子平衡计算、主成分分析等.结果表明:盘锦市冬季PM_(2.5)浓度与水溶性离子浓度特征为文化公园开发区第二中学;SO_4~(2-)、NO_3~-、NH_4~+质量浓度较大;冬季硫氧化率(SOR)和氮氧化率(NOR)的均值均大于0.10,说明SO_4~(2-)、NO_3~-主要由SO_2和NO_x转化而来;阳离子和阴离子当量相关性较强;开发区整体上呈现出中性,文化公园与第二中学呈现出偏碱性;盘锦市PM_(2.5)中水溶性离子主要来源于煤烟尘,生物质燃烧,二次粒子以及扬尘.     

近50 a西北干旱区冬季积雪日数变化特征

论文基于西北干旱区104个站点1961—2010年的日积雪深度、日平均气温、日降水量数据和NCEP/NCAR数据,利用K-means聚类分析、Mann-Kendall法等方法,对西北干旱区冬季积雪日数的时空变化特征及其变化原因进行分析。结果表明:1)冬季积雪日数大值主要集中在阿尔泰山和准噶尔盆地地区,西辽河流域、鄂尔多斯高原、天山、塔里木、阿拉善高原地区冬季积雪日数相对较少,内蒙古高原地区冬季积雪日数基本呈由高纬地区向低纬地区减少的趋势。2)近50 a,西北干旱区冬季积雪日数呈增加趋势,且各区域主要在1984年发生突变现象。内蒙古高原地区内站点冬季积雪日数变化较大,其他分区内站点的冬季积雪日数基本无变化。3)西北干旱区各分区周期变化主要集中在5、10、25 a左右,其中25 a的周期变化最为明显。4)冬季东亚大槽、南支槽的减弱与西风的增强使西北干旱区降水量增加是导致西北干旱区冬季积雪日数增加的主要原因。     

重庆地区石笋δ13C记录的全新世气候环境变化

本文利用重庆市青木关镇狮子洞石笋QM09铀系测年数据和氧碳稳定同位素数据,重建了研究区9.4~0 ka BP的古气候环境演化历史。依据狮子洞石笋δ~(13)C记录变化趋势,将其划分为2个阶段:(1)9.4~3.0 ka BP期间,狮子洞石笋δ~(13)C记录除了在4.2 ka BP附近发生一次短暂的偏重事件外,整体变化比较平缓,石笋δ~(13)C值比较偏轻;同时石笋δ~(18)O值在该期也较为偏轻,暗示了此时段季风强盛,气候温暖湿润,地表植被变化稳定。此时人类活动比较弱,对自然环境的影响小,植被变化主要受自然气候环境的影响;(2)3.0~0 ka BP期间,石笋δ~(13)C记录不再呈现如第一阶段般平稳变动的趋势,在3.0 ka BP时开始波动下降,在经历1.7 ka BP大幅下降后,δ~(13)C便频繁波动大幅升降。石笋δ~(18)O记录显示该时段季风减弱,气候变干,植被退化,土壤水中溶解的CO_2含量减少。加之该期人类活动剧烈,地表自然植被遭到破坏,当地无机环境更多的参与到地下水循环体系中来,使得石笋δ~(13)C逐渐加重。