人字闸的形式及建设要点

临汾市人字闸有钢筋混凝土人字闸、平板拆卸式钢制人字闸、拱形薄板拆卸式钢制人字闸 3种形式。人字闸一般由基础、闸墩、翼墙、放水建筑物、人字架和挡水面板等部分组成。自 2 0世纪 90年代以来 ,临汾市已建成人字闸 2 5 0座 ,总库容 10 5万m3 ,为该市山区沿河农村经济发展起到了较大作用。介绍了人字闸的建设要点。     

人字闸工程的规划设计和施工

人字闸是为拦蓄丘陵山区小泉小水而兴建的一种建筑物，其设计施工简单易行，能有效实现山区利用小泉小水进行灌溉的目的。就人字闸的规划、设计、施工过程及有关问题作一浅述，为类似地区修建人字闸提供参考。     

仙台水库坝型方案比选

根据地形、地质、工程量、工程投资及施工难易程度等情况,对仙台水库下坝线黏土心墙堆石坝、混凝土面板堆石坝、钢筋混凝土闸坝与上坝线钢筋混凝土闸坝四种方案进行了比选,推荐采用下坝线黏土心墙堆石坝。     

古县依托人字阐高效治理小流域的经验与做法

人字闸结构简单、投资省、见效快，是一项山地丘陵区充分利用小泉小水进行小流域治理开发的切实有效措施。介绍了山西古县以人字闸截流灌溉工程为突破口，高效治理小流域的经验与做法。     

永和县农业基础设施发展方略

永和是一个山区农业县，生态环境恶劣，经济十分贫困。“三农”问题突出。经调查研究，需大力进行农业基础设施建设。根据当地实际，宜新建淤地坝802座，人字闸40座。打旱井6000眼，人畜饮水工程86处。这些工程的兴建，不仅可保证粮食生产，而且可促进生产力发展，调整经济结构，加快小康建设步伐。     

基层水管单位水利工程运行与管理对策探究

水利工程是关系国计民生的重要基础工程。近年来,随着我国经济水平的提高,基层水管单位的水利工程运行及管理质量得到了大幅提升。但鉴于其本身运行管理的复杂性,不可避免会产生一些问题。基于此,针对基层水管单位水利工程运行与管理存在的问题进行分析,并提出了合理的对策。     

古县依托人字闸高效治理小流域的经验与做法

人字闸结构简单、投资省、见效快,是一项山地丘陵区充分利用小泉小水进行小流域治理开发的切实有效措施。介绍了山西古县以人字闸截流灌溉工程为突破口,高效治理小流域的经验与做法。     

关于辽宁省水土流失监测点建设与管理的思考

水土保持监测网络建设是水土保持监测工作的基础,是水土流失因子率定和水土保持措施治理效益定额测定的保障。在分析辽宁省水土流失监测点布设格局、水土保持措施设置及运行管理现状的基础上,指出存在的问题及未来工作的方向。     

污染地块修复与风险管控后期管理体系初探

开展地块后期管理是保障人居安全及彻底打赢土壤污染防治攻坚战的关键一环。针对污染地块调查与风险评估、修复与风险管控、效果评估各阶段存在的不确定性，以及修复后地块存在污染物浓度反弹和风险管控措施失效等可能风险，有必要开展污染地块修复和风险管控后期管理研究。为此，基于欧美国家污染地块管理经验，综合考虑我国污染地块环境管理要求，确定了需开展后期管理的地块类型，分析了后期管理过程中长期监测、运行维护、制度控制及回顾性评估4种措施的重要作用，初步构建了污染地块修复和风险管控后期管理框架体系，明确了长期监测对象与目的、监测点位、监测指标、监测频次与周期，运行维护内容，制度控制措施，回顾性评估要求及后期管理的终止条件。实施后期管理是贯彻落实《中华人民共和国土壤污染防治法》的重要体现，将为污染地块修复和风险管控后的安全再利用提供重要保障。     

庄浪县淤地坝建管现状及资源化利用对策

淤地坝是水土流失地区沟道治理中的控制性工程，具有良好的综合效益。庄浪县位于黄河中上游，水土流失比较严重，基于庄浪县淤地坝建设实情，总结淤地坝建成后取得的效益、运行管理经验，梳理存在的问题，提出大力推进淤地坝建设、严格落实运行管理责任及开发利用坝库综合效益等对策，以期为推动新时期小流域生态保护与高质量发展，实现乡村生态振兴、产业振兴提供支持。     

Sorption-desorption of "aged" sulfonylaminocarbonyltriazolinone herbicides in soil

Sorption-desorption interactions of pesticides with soil determine the availability of pesticides in soil for transport, plant uptake, and microbial degradation. These interactions are affected by the physical and chemical properties of the pesticide and soil, and for some pesticides, their residence time in the soil. The objective of this study was to characterize sorption-desorption of two sulfonylaminocarbonyltriazolinone herbicides incubated in soils at different soil moisture potentials. The chemicals were incubated in clay loam and loamy sand soils for up to 12 wks at -33 kPa and at water contents equivalent to 50 and 75% of that at -33 kPa. Chemicals were extracted sequentially with 0.01 N CaCl(2) and aqueous acetonitrile, and sorption coefficients were calculated. Sufficient sulfonylaminocarbonyltriazolinone herbicides remained (>40% of that applied) during incubation to allow calculation of sorption coefficients. Aging significantly increased sorption as indicated by increased sorption coefficients. For instance, for sulfonylaminocarbonyltriazolinone remaining after a 12-wk incubation at -33 kPa, K(d) increased by a factor of 4.5 in the clay loam soils and by 6.6 in the loamy sand as compared to freshly treated soils. There was no effect of moisture potential on sorption K(d) values. These data show the importance of characterization of sorption-desorption in aged herbicide residues in soil, particularly in the case of prediction of herbicide transport in soil. In this case, potential transport of sulfonylaminocarbonyltriazolinone herbicides would be over-predicted if freshly treated soil K(d) values were used to predict transport.     

“摩尔”教学的几点体会

介绍了一种如何在初中化学知识的基础上导入摩尔概念的新颖教学法,展示了这种方法的良好效果。     

生态冷漠症的“诊”与“治”

当今有一部分政府官员患有生态冷漠症,其表现有3种,即面对持续恶化的生态环境麻木不仁,生态建设取得一点成绩便盲目乐观,发生了生态安全问题就怨天尤人。医治生态冷漠症应重点抓好以下3个方面的工作:紧密结合工作实际,切实加强对广大干部的科学发展观教育;完善和推行绿色GDP核算标准,加强对各级政府及其官员的考核;制定和完善有关法律法规,加大对政府行为的约束力度。     

Sorption-desorption of two "aged" sulfonylaminocarbonyltriazolinone herbicide metabolites in soil

Aging (herbicide-soil contact time) has been shown to significantly affect the sorption-desorption characteristics of many herbicides, which in turn can affect the availability of the herbicide for transport, plant uptake, and microbial degradation. In contrast, very little work in this area has been done on herbicide metabolites in soil. The objective of this study was to characterize the sorption-desorption of sulfonylaminocarbonyltriazolinone herbicide metabolites incubated in soils at different soil moisture potentials. A benzenesulfonamide metabolite and a triazolinone metabolite from sulfonylaminocarbonyltriazolinone herbicides were incubated in clay loam and loamy sand soils for up to 12 weeks at -33 kPa and at water contents equivalent to 50 and 75% of that at -33 kPa. Chemicals were extracted sequentially with 0.01 N CaCl(2) and aqueous acetonitrile (solution and sorbed phase concentrations, respectively), and apparent sorption coefficients (K(d,app)) were calculated. Sufficient metabolite remained during the incubation (>55% of applied) to allow determination of the coefficients. The initial aging period (2 weeks after application) significantly increased sorption as indicated by increased K(d,app) values for the chemical remaining, after which they remained relatively constant. After 12 weeks of incubation at -33 kPa, K(d,app) values for benzenesulfonamide and triazolinone increased by a factor of 3.5 in the clay loam soil and by a factor of 5.9 in the loamy sand as compared to freshly treated soils. There was no effect of moisture potential on aged apparent K(d,app) values. These data show the importance of characterization of sorption-desorption in aged herbicide residues, including metabolites, in soil, particularly in the case of prediction of herbicide residue transport in soil. In this case, potential transport of sulfonylaminocarbonyltriazolinone herbicide metabolites would be overpredicted if freshly treated soil K(d) values were used to predict transport.     

Production and composition of cider spirits distilled in "alquitara"

The capacity of alquitara (a traditional distillation system) to produce cider brandies is evaluated. To do so, the chemical composition of 12 fractions obtained during the distillation process and the cider brandies obtained from five ciders were analyzed (alcohol strength, methanol, volatile substances, furfural, and metals), taking into account European and Spanish legislation. During the course of distillation, an important increase in methanol, furfural, 2-phenylethanol, and metals in the last fractions was observed, while fusel oils were more abundant in the first fractions collected. Only acetaldehyde behaved differently, showing a minimum concentration in the middle fractions that might be explained by its formation on the surface of alquitara. On the other hand, the final distillates obtained by means of this method complied with the considered regulations. Worth highlighting in this regard are the low levels of a potential toxin such as methanol, as well as the detection of a constant ratio for methanol, ethanol, and fusel oil for the pairs of cider/spirits analyzed, which could be interpreted as an indication of good uniformity in the distillation system and method, thus guaranteeing product quality.     

“3S”技术在农业非点源污染研究中的应用

应用“3S”技术进行农业非点源污染预测、控制和管理是最新的动向。为此结合国内外“3S”技术在农业非点源污染研究中的应用现状 ,阐述了“3S”技术在非点源污染研究中的应用意义和方法 ,并对“3S”技术在此领域发展动态进行了展望     

“猪-沼-果”水土保持综合治理模式简析

 “猪—沼—果”工程是20世纪90年代以来江西省赣南等水土流失严重地区综合治理水土流失的一种新模式,对巩固和促进治理成果取得了积极有效的作用。通过介绍“猪—沼—果”综合治理模式的内涵及“猪—沼—果”产业循环生态链,对“猪—沼—果”综合治理模式在小流域治理中的作用和效益进行全面阐述。其作用主要表现在3个方面:1)缓解能源紧缺的矛盾,保护自然植被,巩固治理成果;2)提供有机肥料,改善水土流失地土壤养分条件,促进开发性治理;3)促进小流域经济的发展,加快脱贫致富的步伐。同时,取得了显著的水土保持效益、生态效益和经济效益。     

染色体消失法在小麦育种中应用的研究

用不同世代的小麦杂种为母本和鸭茅状摩擦禾进行属间杂交.利用杂合子发育过程中来自父本的染色体完全、迅速地消失得到大量单倍体胚.借助于胚培养和染色体加倍技术从杂合体小麦快速得到性状稳定的纯系.本文首次继花药培养法之后向读者介绍另一种以常规育种与生物技术手段相结合的小麦单倍-二倍化育种方法.     

西藏"一江两河"地区土壤退化特征

西藏"一江两河"地区日趋严重的土壤退化是由其生态环境的脆弱性、地貌结构的特殊性,特别是人类影响和干预的广泛性、非合理性决定的。在阐述土壤退化类型、特征的基础上,就土壤退化的发生机制进行了综合分析。     

粮食生产潜力短期预测的“趋势-波动模型”的验证

应用全国、31个省、6个典型地区和16个典型县的数据对粮食生产潜力短期预测的"趋势-波动模型"进行了系统性的验证和讨论。研究结果表明:(1)预测误差大小反映短期生产潜力的预测精度,预测误差大的主要原因是经济发达地区高产农田被大量占用和(或)蔬菜、水果种植面积大幅度增加而短期内使粮食单产下降;(2)小趋势修正方法是"趋势-波动模型"中不可缺少的一部分,它能将大趋势预测不能包括的短期如气象因素、科技投入、社会因素等影响纳入预测中,提高预测精度;(3)就我国近些年来的实际情况而言,越是经济发达的地区短期生产潜力的波动越大;同样发达地区短期潜力存在增加-下降-回升阶段;(4)就短期生产潜力预测精度而言:国家级大于省级、省级大于地区级、地区级大于县级;不同省、不同地区、不同县之间预测精度差别比较大,这与境内气候的互补性和农田抗御自然灾害的能力有关。