1991年江淮流域特大洪涝与厄尼诺

1991年初夏,持续性大暴雨导致江淮流域特大洪涝灾害.本文分析了降水量与洪涝的分布和演变及其基本大气环流特征,并着重研究了洪涝的主要成因——厄尼诺现象.文中指出.江淮流域的大或特大洪涝,大多发生在厄尼诺事件的同年或次年.厄尼诺、反厄尼诺与北半球低纬100和500hpa大气环流有长达15个月(从同年6月至次年8月)的显著性相关.厄尼诺事件的影响以各种复杂机制,先在低纬作纬向扩展传播.再向中高纬度频散传播.从而对气象与海洋灾害作出严重影响.     

Accumulation and Chemical Fractionation of Heavy Metals in Andisols after a Different, 6-year Fertilization Management (8 pp)

Goal, Scope and Background Andisols are widespread in Japan and have some special properties such as high anion exchange capacity, low bulk density, and high organic matter content, which might influence the accumulation or chemical fractionation of heavy metals. However, few such data exist in Japanese andisols. The primary objective of this study was to investigate the distribution and chemical fractions of Cu, Zn, Ni, and Cr in the soil profiles and subsequently to assess their potential environmental hazard. Materials and Methods Soil samples were taken from a field experiment conducted on Japanese andisols, which had received either swine compost or chemical fertilizers for 6 years. Concentrations of Cu, Zn, Ni, and Cr were determined for all of the obtained extract solutions by ICP-AES. Results and Discussion Considerably higher total concentrations of Cu and Zn were observed in the top 20 cm layer of the compost-amended soil, relative to the unfertilized soil, while chemical fertilizers had little effect. Application of the swine compost increased the concentrations of Cu and Zn, but not Ni and Cr, in all fractions in the top 20 cm layer. The greatest increase in the organically bound fraction (OM) Cu and dilute acid-exchangeable fraction (DAEXCH) Zn was observed. This suggests that Cu and Zn are potentially bioavailable and mobile in the andisol profiles after 6-year consecutive applications of the swine compost. On the other hand, distribution of Cu, Zn, Ni and Cr among various soil fractions was generally unaffected by chemical fertilizers. Conclusions We observed that 6-year consecutive applications of the swine compost led to an increase in total metals of Cu and Zn, as well as their all-chemical fractions, in the top 20 cm soil layers. Potential hazard of heavy metals, especially of Cu and Zn, as a result of the use of swine compost on andisols, must be taken into account. Recommendations and Outlook The long-term effect of the accumulation of heavy metals, particularly Cu and Zn, in various plant tissues and soils, as well as their potential risk to surface water via runoff and groundwater via leaching, needs to be carefully considered. Further investigations in the long-term experiments are therefore necessary. - Abbreviations. EXCH, exchangeable fraction of metals; DAEXCH, dilute acid-exchangeable fraction of metals; FeMnOX, iron and manganese-oxide-bound fraction; OM, organically-bound fraction; RESD, residual fraction. COMPOST, SRNF, RANF, and CONTROL stand for compost (from swine wastes), slow-release nitrogen fertilizer (coated urea), readily available nitrogen fertilizer (including NH4-N, P, and K fertilizers), and no fertilizer application, respectively.     

Phylogenetic Comparative Methods Strengthen Evidence for Reduced Genetic Diversity among Endangered Tetrapods

Abstract: The fitness of species with little genetic diversity is expected to be affected by inbreeding and an inability to respond to environmental change. Conservation theory suggests that endangered species will generally demonstrate lower genetic diversity than taxa that are not threatened. This hypothesis has been challenged because the time frame of anthropogenic extinction may be too fast to expect genetic factors to significantly contribute. I conducted a meta‐analysis to examine how genetic diversity in 894 tetrapods correlates with extinction threat level. Because species are not evolutionarily independent, I used a phylogenetic regression framework to address this issue. Mean genetic diversity of tetrapods, as assessed by protein heterozygosity, was 29.7–31.5% lower on average in threatened species than in their nonthreatened relatives, a highly significant reduction. Within amphibians as diversity decreased extinction risk increased in phylogenetic models, but not in nonphylogenetic regressions. The effects of threatened status on diversity also remained significant after accounting for body size in mammals. These results support the hypothesis that genetic effects on population fitness are important in the extinction process.     

改性菌丝体对Ni2+的吸附特性研究

通过专利对菌丝体进行了改性。所制备的改性菌丝体对重金属离子具有良好的吸附效果。结果表明 ,其对Ni2 + 的吸附容量 6 3.2mg/g (初始水溶液中Ni2 + 浓度为 2 0 0mg/L) ,是甲壳素吸附剂的 3.3倍 (19.1mg/g) ,与壳聚糖吸附剂相比吸附容量提高了 135 % ,与D75 1与南开 15 2相比吸附容量非常接近。用 0 .5 %— 0 .2 %的解吸剂便可以完全解吸 ,能够重复使用达 6次以上。本文还研究了改性菌丝体对Ni2 + 的吸附过程中重要的影响因素 ,结果发现 ,在微碱性 (pH =8— 9)条件下 ,改性菌丝体可以把初始浓度高达 80 0mg/L的Ni2 + 溶液一次性降低到 17mg/L ,为改性菌丝体在工业废水处理中的应用奠定了良好的基础。     

掺Ni2+的TiO2颗粒光催化性能的研究

通过溶胶-凝胶法制备掺杂Ni2 的纳米TiO2,并用XRD和TEM进行了表征,发现Ni2 的掺杂减小了TiO2颗粒的粒径,Ni2 /TiO2晶型为锐钛型.通过对目标物罗丹明B的光催化降解实验,发现Ni2 的掺杂提高了TiO2的光催化活性,其降解罗丹明B的反应遵从一级反应动力学方程,Ni2 惨杂量为1.2%时的光催化活性最高.     

双波长标准加入法测微量镍

通过加入掩蔽剂酒石酸，使Zn(Ⅱ）与1－（2－吡啶偶氮）－2－奈酚形成的配合物吸光度降低，而对应的配合物吸光度基本不变，从而提高了大量Zn(Ⅱ)存在下Ni(Ⅱ）测定的准确度，用于测定镀锌溶液中的Ni(Ⅱ），结果令人满意。     

THE EFFECT OF EL NIÑO-RELATED DROUGHT ON THE RECOVERY OF ACIDIFIED LAKES

Although SO₂ emissions and deposition rates havedeclined substantially since the implementation of sulphuremission control programmes in North America [1], recovery(measured as decreases in concentrations) of affected lakes in central Ontario has been much less substantial thananticipated based on the decrease in deposition. The slowrecovery is attributed to the reoxidation and release of storedsulphur in catchments. Reduced sulphur retained in previousyears when sulphur deposition was higher is exposed to air andoxidized during severe droughts, then exported duringsubsequent wet periods. Elevated stream concentrations and export rates occur in the autumns of yearswith prolonged severe droughts, particularly in catchments withextensive wetlands. Drought in our study catchments occurred inyears following strong El Niño events. When the SouthernOscillation Index (SOI) was strongly negative (1976–77, 1982–83,1986–87, 1991–92, 1993–94) the frequency of occurrence ofdrought the following summer in small catchments with shallowoverburden was extremely high. A lakes rate of recovery fromacidification depends upon the amount of excess reduced Sthat has been stored in anoxic zones in the catchment (largely afunction of the extent of wetlands) during years of elevated Sdeposition rates, and the frequency and severity of droughts. Iflong-term changes in global or regional climate alter thefrequency or magnitude of El Niño-related droughts, therecovery of acidified lakes will be affected.     

含镍废液中镍回收的研究

本文研究了强碱性条件下,以乙二胺为络合剂,用水合肼把二价镍离子还原为单质镍的方法。经过大量实验,镍粉的产率在99％以上,其纯度也在99％以上。通过这种方法,既回收了镍,又降低了对环境的污染,结果令人满意。     

企业安全能力及其进化取向的灰色关联度分析(GRA)判定法研究

依据企业资源理论与能力理论的具体研究成果,分析了企业安全能力与企业安全资源之间的关系,进而研究了企业安全能力进化的取向问题。探讨了企业中的安全资源和安全能力及其相互关系,并从安全能力进化取向、安全资源优势、企业竞争优势三者之间存在的内在联系,运用GRA(GrayRelationAnalysis)(灰色关联度分析)方法提出了一种企业安全能力进化取向的判定方法。该方法为企业如何利用有限的资金合理选择安全能力进化的取向,以及制定相应的安全资源积累的顺序,提供了一种理论依据。     

SUWANNEE RIVER LONG RANGE STREAMFLOW FORECASTS BASED ON SEASONAL CLIMATE PREDICTORS1

ABSTRACT: A study of the influence of climate variability on streamflow in the southeastern United States is presented. Using a methodology previously applied to watersheds in Australia and the United States, a long range streamflow forecast (0 to 9 months in advance) is developed. Persistence (i.e., the previous season's streamflow) and climate predictors of the previous season are used to forecast the following season's (winter and spring) streamflow of the Suwannee River located in northern Florida. The winter and spring streamflow is historically the most likely to have severe flood events due to large scale cyclonic (frontal) storms. Results of the analysis indicated that a strong El Nino‐Southern Oscillation (ENSO) signal exists at various lead times to the winter and spring streamflow of the Suwannee River. These results are based on the high correlation values of two commonly used measurements of ENSO strength, the Multivariate ENSO Index (MEI) and Sea Surface Temperature Range 1. Using the relationships developed between climate and streamflow, a continuous exceedance probability forecast was developed for two Suwannee River stations. The forecast system provided an improved forecast for ENSO years. The ability to predict above normal (flood) or below normal (drought) years can provide communities the necessary lead time to protect life, property, sensitive wetlands, and endangered and threatened species.