共查询到20条相似文献，搜索用时 62 毫秒
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通过对棱角山矾的生物学特性分析,探讨了棱角山矾的繁殖关键技术。挖掘这一乡土树种的开发价值,旨在推动棱角山矾,这一集香化、绿化、美化于一身,且具有较强抗性的优质园林树种在较大范围内推广应用。
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采用自主研发"一种环保植物基质"替代泥炭土,用于石漠化荒山棱角山矾育苗试验,研究其对棱角山矾生长影响。采用单因数敏感分析,筛选出适合其快速繁殖的最佳基质配比。A2基质配比最佳,对棱角山矾扦插苗初生根时间、生根数、成活率及次年生长速率、分枝条数影响显著。试验证明,该环保植物基质能替代传统泥炭土。适量加砂能改善土壤通气性,砂量不宜超过50%。年生长周期重复2次,其表征的休眠期与生长期为棱角山矾试验林的合理育苗时间提供依据。 相似文献
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有机废水处理中的高级氧化技术 总被引：3，自引：0，他引：3
综述了高级氧化技术的原理,介绍了O3/UV、H2O2/UV、O3/H2O2组合过程、化学氧化技术及电化学氧化技术五种典型的高级氧化技术,阐述了高级氧化技术降解有机污水的机理以及在水处理中的应用进展。指出了高级氧化过程应用领域应扩展到水体中难降解的持久性有机污染物,并应加强高级氧化过程所需新型反应器的研制,以便进一步强化废水的降解,提高其处理效率。 相似文献
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指出了排污许可制度改革是我国当前生态文明体制改革的重要一环,从排污许可制度的实施情况来看,企业在实际基层实践过程中仍存在着一些问题。对企业排污许可证申请及证后执行等基础实践过程中存在的较为常见的问题进行了总结与分析,以期为企业及相关监管部门提供参考借鉴。 相似文献
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Geochemical processes in central European oak ecosystems (Quercus petraea and Quercus robur) suffering stand decline were studied in two oak stands of the Weinviertel, Lower Austria, about 30 km north of Vienna. Stores of chemical elements were determined by soil and biomass inventories. Deposition input was monitored over a 2 year period by bulk sampling of throughfall. Soil solution chemistry was studied by tension lysimetry over a 1 year period. Mineral nutrition of oak was judged by foliar analysis. Bulk deposition rates were 10–12 kg N ha−1 year−1, and 15–20 kg S ha−1 year−1. Total annual nitrogen gain is high. Both systems lose calcium and magnesium. Foliar nutrient levels indicate sufficient nutrition with main mineral nutrients, except for magnesium, which is in moderately low supply. Based on these findings, the hypothesis that pollutant deposition has been the cause of a sudden and severe appearance of decline symptoms in the second half of the 1980s must be dismissed. The data on deposition rates and ecosystem nutrient status, however, indicate that the soil of both systems is acidifying, nitrogen stores are increasing, and magnesium pools are depleted. If deposition of pollutants continues at current rates, a slow but steady degradation of many oak ecosystems in the Austrian Weinviertel is inevitable. 相似文献
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氯化锌法木质活性炭生产过程中,有两个主要污染散发源。1,大气污染源;2,废水污染源。在实验室条件下,从废气中损失的氯化锌约为氯化锌损失总量的1/3,废水中为2/3。研究表明,废水主要污染物质由残存的盐酸、氯化锌、氯化亚铁、二氯化铁、氯化镁、氯化钙以及Al~(3 )、K~ 、Mn~(2 )等所组成。而有机污染物质含量甚微。这样的废水,在适当条件下(pH值及石灰添加量等),采用中和絮凝的方法能得到有效的处理;添加适当高分子絮凝剂能改善絮凝体的沉降速率和过滤速率。研究结果也表明,污泥的回收利用以及处理过的废水循环回用至关重要。 相似文献
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利用长期定位观测方法对大夫山森林公园的大气质量进行监测,分析了大夫山森林公园大气污染源的种类、数量、分布规律,包括NO、NO2、NOx和SO2浓度的日变化规律、季节变化规律进行了探讨。在此基础上,通过分析森林公园大气污染物超标率和分担率情况来评价大夫山森林公园大气质量的影响。结果表明,大夫山森林公园的大气质量非常良好,SO2和NOx秋冬季对大气环境有轻微污染,污染分担率最大的SO2,其次是NOx,而NO和NO2对大夫山森林公园环境不产生影响。为进一步提高森林公园的大气环境质量,建议增加冬季常绿阔叶树种。
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随着国家政策对汽车业经济性和环保指标的要求日益严格，汽车排放控制显得越加重要，各大厂家的研发成本中已有近三成的投入花费在排放控制上。但由于汽车的长时间使用和燃料品质的良莠不齐及氧传感器和三元催化器的工况不佳而导致的故障屡见不鲜。这不仅大量消耗厂家的售后成本，也增加了最终用户的使用成本。因此探讨处理好三元催化器与氧传感器之间的工作依存关系显得很重要。 相似文献
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以四川省苍溪县工业园区为例,采用单因子评价法与箱式大气质量模型对区域大气环境质量进行评价与预测,结果显示,工业园所在区域环境空气质量符合《环境空气质量标准》Ⅱ级标准。工业园区SO2的大气环境容量为:284t/a,TSP为:950.2t/a,满足总量控制和环境容量要求。在此基础上,提出了源头把关+末端治理+跟踪监测的污染综合防治对策:1)严格执行政策总量控制,严把企业入园关;2)优化能源结构,推行清洁生产;3)加强宣传教育,树立科学发展观;4)加强评价后跟踪监测,督促环保措施落实到位。 相似文献
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《Scandinavian Journal of Forest Research》2012,27(5):427-435
In Scandinavia, moose (Alces alces L.) sometimes cause severe browsing damage to economically-important pine. Moose-vehicle accidents have spurred construction of fences along roads, and these may interfere with moose migration between summer and winter ranges, or the road alone may be a barrier. If this happens and moose build up along roads, landowners may suffer economically. Therefore, this study investigated whether roads, fences or other factors influence the use of young pine stands by moose. Eighty stands along roads in northern Sweden were evaluated in which individually-browsed branches were counted on 9972 pines. Moose browsing was not significantly related to birch (Betula pendula Roth, B. pubescens Ehrh.) density, nor did it differ between pines (Pinus contorta Douglas or P. sylvestris L.). However, increased pine density, site productivity and proximity to a highway were associated with increased browsing. Further large-scale studies are needed to understand moose habitat selection and the effects of roads. 相似文献