略论信息技术在农业气象灾害减灾中的应用

农业气象灾害减灾对策是一项十分复杂的系统工程，其系统可划分为两个子系统：农业气象灾害子系统和减灾对策子系统。农业气象灾害子系统包括灾害的发生、发展到消亡的整个过程。减灾对策子系统是指减轻灾害的对策措施，可概括为灾前防御、灾中抗御、灾后补救等。其系统涉及到灾害的监测、预报、防御、抗御、治理、灾情评估和减灾效益的分析等环节。因此，对这样一个系统工程，除总结和继承传统的农业气象灾害的减灾方法外，还需要利用现代的信息技术；遥感技术、人工智能技术、作物模拟技术等来提高防灾、减灾的能力。     

放牧对祁连山高寒金露梅灌丛草甸土壤微生物的影响

以祁连山北支冷龙岭东段南麓的甘柴滩夏季牧场集体长期混合(藏系绵羊、牦牛)放牧的高寒金露梅(Potentilla fruticosa)灌丛草地为对象,采用平板涂抹分离法和氯仿熏蒸法对不同放牧压力梯度下土壤微生物(细菌、真菌和放线菌)和土壤微生物碳、微生物氮量进行研究,结果表明:不同放牧压力梯度下,金露梅灌丛和丛间草地土壤微生物以细菌占绝对优势,放线菌和真菌较少,垂直分布明显;随着放牧压力梯度的增加,金露梅灌丛和丛间草地,0～25 cm土层中的细菌、放线菌、真菌及微生物碳和微生物氮数量呈降低趋势,其降低程度与放牧压力梯度呈直线正相关.与无放牧金露梅灌丛相比0～25 cm土层的细菌、真菌、放线菌最大降幅分别为49.64%、37.76%和46.64%;金露梅灌丛土壤微生物碳量占土壤有机碳的比例变化为0.85%～0.43%,微生物氮占土壤全氮的0.90%～1.11%,微生物量对土壤营养库的贡献率较低;土壤微生物量和土壤有机质呈显著线形正相关;土壤细菌数量和土壤水分呈显著线形正相关.     

酸雨胁迫下黑壳楠Lindera megaphylla Hemsl.幼苗在夏季和秋季的生理生态特性

浙江为酸雨危害严重地区之一,而植物在酸雨胁迫下的生长和生理变化情况可以衡量其对酸雨的耐受能力,亦可作为植被引种、经营和管理的参考依据.采用盆栽法,研究了在不同季节不同强度酸雨胁迫下黑壳楠Lindera megaphylla Hemsl.的生理生态特性,设置了3个酸雨处理:重度酸雨处理(pH2.5)、中度酸雨处理(pH4.0)和酸雨对照处理(pH5.6).研究结果表明:①酸雨、季节以及酸雨和季节的交互效应对黑壳楠的株高、地径和叶绿素相对含量没有显著影响.②黑壳楠的最大净光合速率(Amax)、表观量子效率(AQE)、光补偿点(LCP)和暗呼吸速率(Rd)对酸雨胁迫敏感,而季节并未显著影响到植物的光合特性.③酸雨胁迫显著影响黑壳楠的气孔导度(Gs)、蒸腾速率(Tr)和水分利用效率(WUE).季节对黑壳楠的蒸腾速率(Tr)和水分利用效率(WUE)影响显著.酸雨和季节的交互效应极显著影响到植物的胞间CO2(Ci)浓度和蒸腾速率(Tr).研究表明夏季黑石楠受酸雨胁迫的影响比秋季严重.重度酸雨胁迫严重影响到黑壳楠的生理生长,在酸雨危害严重地区如浙江不适宜大量种植黑壳楠.     

除草剂2，4-D在土壤中吸附常数的测定

介绍除草剂２,４－Ｄ在４种不同有机碳含量、不同ｐＨ值的土壤中吸附常数的测定．结果表明,４种土壤对２,４－Ｄ的吸附等温线均符合非线形的Ｆｒｅｕｎｄｌｉｃｈ吸附等温式,其有机碳吸附常数的平均值为２３９．６．２,４－Ｄ的吸附常数与土壤有机碳含量呈正相关,土壤的ｐＨ值对２,４－Ｄ的吸附也有一定的影响．     

Distribution of mercury in the combustion products from coal-fired power plants in Guizhou,southwest China

Method 30B and the Ontario Hydro Method (OHM) were used to sample the mercury in the flue gas discharged from the seven power plants in Guizhou Province, southwest China. In order to investigate the mercury migration and transformation during coal combustion and pollution control process, the contents of mercury in coal samples, bottom ash, fly ash, and gypsum were measured. The mercury in the flue gas released into the atmosphere mainly existed in the form of Hg°. The precipitator shows a superior ability to remove Hg^p (particulate mercury) from flue gas. The removal efficiency of Hg²⁺ by wet flue gas desulfurization (WFGD) was significantly higher than that for the other two forms of mercury. The synergistic removal efficiency of mercury by the air pollution control devices (APCDs) installed in the studied power plants is 66.69–97.56%. The Hg mass balance for the tested seven coal-fired power plants varied from 72.87% to 109.67% during the sampling time. After flue gas flowing through APCDs, most of the mercury in coal was enriched in fly ash and gypsum, with only a small portion released into the atmosphere with the flue gas. The maximum discharge source of Hg for power plants was fly ash and gypsum instead of Hg emitted with flue gas through the chimney into the atmosphere. With the continuous upgrading of APCDs, more and more mercury will be enriched in fly ash and gypsum. Extra attention should be paid to the re-release of mercury from the reutilization of by-products from APCDs.

Implications: Method 30B and the Ontario Hydro Method (OHM) were used to test the mercury concentration in the flue gas discharged from seven power plants in Guizhou Province, China. The concentrations of mercury in coal samples, bottom ash, fly ash, and gypsum were also measured. By comparison of the mercury content of different products, we found that the maximum discharge source of Hg for power plants was fly ash and gypsum, instead of Hg emitted with flue gas through the chimney into the atmosphere. With the continuous upgrading of APCDs, more and more mercury will be enriched in fly ash and gypsum. Extra attention should be paid to the re-release of mercury from the reutilization of by-products from APCDs.     

城市污水再生处理过程中壬基酚的迁移转化行为研究

采用SPE—GC—MSD-SIM方法，分析了壬基酚在污水再生处理全过程中的迁移转化行为与归宿。研究表明，在污水二级生物处理流程中，壬基酚主要来源为原污水和泥区回流液；壬基酚的去除途径有一沉池生污泥的吸附迁移作用和曝气池单元的生物降解转化作用，其中一沉池生污泥的吸附去除29．8％，曝气池生物降解54．4％，NP总去除率为84．2％。絮凝、过滤和消毒的污水再生深度处理工艺对壬基酚的迁移转化作用不明显。     

基于WEBGIS的城市建筑物震害评估方法研究

城市是人口高度密集且财富集中的地区,一旦发生地震,城市遭受的破坏和打击是巨大的。由于地震造成损失的主要原因是建筑物的倒塌及破坏,因此通过开发基于WEBGIS的城市建筑物震害预测信息系统,对城市建筑物震害的损失估计有着十分重大的意义。利用WEBGIS网络化空间分析技术,结合城市区域特征分区易损性模型,同时采用综合系数评价方法,对震时城市内的钢混、砖混、砖木、石砌、土木等五类结构进行了易损性计算,最后得出了各类建筑物破坏的严重程度以及由此造成的损失,为震后应急指挥管理提供了指导意见。最后结合在福建省地震局地震灾情快速评估系统中的实际应用,说明该方法的实用性和有效性。     

天灾死亡人数不再是国家机密

近年来灾情数字已逐步公开 根据形势发展和救灾工作的需要,从2005年8月起,我国对全国及省、自治区、直辖市因自然灾害导致死亡人员的总数及相关资料解密。     

Homogeneous and heterogeneous photolysis of nitrate in the atmosphere: state of the science,current research needs,and future prospects

● Recent advances in the photolysis of nitrate/HNO₃ are reviewed. ● Mechanisms and key factors affecting the photolysis of nitrate/HNO₃ are summarized. ● Atmospheric implications and future research recommendations are provided. Nitrate is an important component of atmospheric particulate matter and affects air quality, climate, human health, and the ecosystem. Nitrate was previously considered a permanent sink for nitrogen oxides (NO_x). However, this viewpoint has been challenged in recent years because growing research evidence has shown the transformation of nitrate into NO_x (i.e., renoxification). The photolysis of nitrate/HNO₃, especially in the particulate phase or adsorbed on particles, can be a significant renoxification process in the atmosphere. The formation and photolysis of nitrate in aerosol not only change the diurnal variation of NO_x, but also provide long-distance transport of NO_x in the form of nitrate, which affects local and regional atmospheric chemistry and air quality. This review summarizes recent advances in the fundamental understanding of the photolysis of nitrate/HNO₃ under various atmospheric conditions, with a focus on mechanisms and key factors affecting the process. The atmospheric implications are discussed and future research is recommended.     

光子相关光谱（PCS）在无机高分子絮凝剂形态表征中的应用

本文运用现代先进的微粒检测手段光子相关光谱对常见的两类无机高分子絮凝剂的形态进行了表征。实验结果表明：在所测聚合氯化铁溶液中，体系呈较为单一的集中分布，由平移扩散系数计算得到平均有效直径在５－１１ｎｍ左右。在所测聚合氯化铝溶液中，主要为双峰分布，熟化后样品约为２－５ｎｍ的小颗粒与数十ｎｍ以上分布较宽的聚集体，另外，本文对光子相关光谱在形态表征中的优缺点及其它应用的可能性也作了一定的论述。