二氧化硫对植物新陈代谢的影响(Ⅰ)——对气孔、膜透性与物质代谢的影响

从气孔反应?膜透性变化和酶活性变化3个方面综述了二氧化硫对植物新陈代谢的影响?分析了在SO₂作用下气孔的运动规律,气孔变化与SO₂暴露浓度?暴露时间之间的关系;总结了SO₂对植物膜透性的影响及影响机理;阐述了SO₂对过氧化物酶?超氧化物岐化酶等几种酶的影响      

Effect of sludge treatment on the bioaccumulation of nonylphenol in grass grown on sludge-amended soil

We studied the accumulation of p353-nonylphenol residues in the biomass of grass grown in soil amended with sewage sludge submitted to various conditioning/dewatering treatments. Incubation experiments were conducted growing Poa pratensis in sludge-amended soils and applying one ¹⁴C-labelled isomer of nonylphenol in the different systems. More metabolites than parent compounds were recovered in both roots and leaves of the grass. The type of sludge conditioning and dewatering treatment had a slight effect on the bioaccumulation of nonylphenol and its metabolites. When the grass was cultivated in soils amended with dewatered sludge without conditioning pretreatment, an increased accumulation was observed in the roots, while the final biomass of the grass was lower.     

Detecting general plant functional type responses in fragmented landscapes using spatially-explicit simulations

Habitat loss and increasing landscape fragmentation are known to be key forces driving the ongoing loss of plant species diversity. While the combined effects of increasing isolation and decreasing population size have been studied intensively; it is less understood how plant population performance in heterogeneous landscapes is affected by changes in fragmentation alone.     

Improving human micronutrient nutrition through biofortification in the soil–plant system: China as a case study

Micronutrient malnutrition is a major health problem in China. According to a national nutritional survey, approximately 24% of all Chinese children suffer from a serious deficiency of iron (Fe) (anemia), while over 50% show a sub-clinical level of zinc (Zn) deficiency. More than 374 million people in China suffer from goiter disease, which is related to iodine (I) deficiency, and approximately 20% of the Chinese population are affected by selenium (Se) deficiency. Micronutrient malnutrition in humans is derived from deficiencies of these elements in soils and foods. In China, approximately 40% of the total land area is deficient in Fe and Zn. Keshan and Kaschin-Beck diseases always appear in regions where the soil content of Se in low. The soil–plant system is instrumental to human nutrition and forms the basis of the “food chain” in which there is micronutrient cycling, resulting in an ecologically sound and sustainable flow of micronutrients. Soil-plant system strategies that have been adopted to improve human micronutrient nutrition mainly include: (1) exploiting micronutrient-dense crop genotypes by studying the physiology and genetics of micronutrient flow from soils to the edible parts of crops; (2) improving micronutrient bioavailability through a better knowledge of the mechanisms of the enhancers’ production and accumulation in edible parts and its regulation through soil-plant system; (3) improving our knowledge of the relationship between the content and bioavailability of micronutrients in soils and those in edible crop products for better human nutrition; (4) developing special micronutrient fertilizers and integrated nutrient management technologies for increasing both the density of the micronutrients in the edible parts of plants and their bioavailability to humans.     

氧化塘深度处理焦化废水的初步研究

焦化废水经过常规的二级处理后,ＣＯＤ和ＮＨ３－Ｎ往往难到达到国家排放标准,以活性污泥法处理焦化废水的出水水质为依据,采用氧化塘深度处理焦化废水,其ＣＯＤ和ＮＨ３－Ｎ均可达到国家排放标准。因此,只要只要条件控制得当,运用氧化塘处理低浓度焦化废水可以获得较好处理效果。     

关于欧盟植物保护品对鸟类和哺乳动物的风险评估的反思：过去、现在和未来

植物保护品在农作物上的使用会导致鸟类和哺乳动物接触有毒化学物质。在欧盟,关于此类暴露的风险评估均以当前(2009)欧洲食品安全局(EFSA)颁布的指导性文件为依据,与之前的版本相比,该文件在理论风险评估的可实现性方面有所提高(SANCO/4145/2000)。自从7年前实施2009 EFSA 指导性文件以来,基于此已经对众多植物保护品的毒性进行了成功地评估。然而,在今后的修订版本中仍然存在需要改进的重要方面。这篇焦点文章讨论了目前方案的风险评估经验,包括输入参数的保守水平和监管当局的解释以及如何在不远的将来对指导性文件进行修订提出建议。明确了推进指导文件的几方面建议,例如与生态相关的鸟类和哺乳动物生殖端点的推导和情境风险评估中建模方法的使用。在完善现有数据库方面,本文也有所强调,包括校对全欧洲相关焦点物种和扩大食物残留数据库。为了能够在将来形成一个真实可用的指导性文件,强烈建议在产业、监管和欧洲食品安全局等部门之间进行开放和建设性的沟通和交流。这样的合作也将鼓励会员国之间的融合,从而减轻产业和监管机构工作负荷。
精选自Amy C. Brooks, Mike Fryer, Alan Lawrence, Juan Pascual, Rachel Sharp. Reflections on bird and mammal risk assessment for plant protection products in the European Union: past, present and future. Environmental Toxicology and Chemistry: Volume 36, Issue 3, pages 565–575, July 2017. DOI: 10.1002/etc.3719
详情请见http://onlinelibrary.wiley.com/wol1/doi/10.1002/etc.3719/full
     

艾士卡-离子色谱法测定植物叶片中含硫量

建立了艾士卡-离子色谱测定植物中含硫量的方法,该法利用植物样品与艾士卡试剂的混合灼烧,将植物中的硫转化为硫酸盐进行测定,再根据硫酸根的含量计算植物中含硫量。经验证,该方法检出限为0.01%,精密度为2.3%~3.9%,回收率为91.7%~104.3%,适用于植物中含硫量的测定。     

植物性食品中拟除虫菊酯类农药测定方法的改进

基于色素和含水率两方面的考虑,选用了大米、荼叶和西红柿作为实验介质,在植物性食品中拟除虫菊酯类农药提取条件和净化条件等方面均进行了改进和优化.结果发现,采用正己烷/丙酮混合液(97.5∶2.5,V/V)提取植物性食品中菊酯类农药,40～50℃下超声萃取40min;选用弗罗里硅土和活性炭混合填充物制作层析柱;选用石油醚/乙酸乙酯(9∶1,V/V)作为洗脱溶剂,实验回收率达70%以上,结果令人满意.     

城市污水处理厂进水CODCr和SS的相关性研究

CODCr和SS为城市污水处理厂日常必测项目。通过对嘉兴市联合污水处理厂进水CODCr和SS数据进行回归分析,找出了两者之间的线性关系,建立了回归方程,从而得出用已测定的SS来预测CODCr的简便方法。经检验,在一定时间段内预测结果的准确性较高,具有较好的实际应用价值,可以大大提高工作效率和水质的预测能力。     

The effects of disturbance based management on the dynamics of Mediterranean vegetation: A hierarchical and spatially explicit modeling approach

The eastern Mediterranean region has been subjected to intensive human disturbance in the past 10,000 years, mainly in the forms of agro-pastoral activities such as grazing, shrub clearing, and prescribed burning. This disturbance history resulted in the formation of highly heterogeneous landscapes, characterized by high biodiversity. Recent changes in human activities have resulted in a decrease of landscape heterogeneity, leading to decreasing biodiversity and increasing fire risk. To conserve heterogeneity, land managers apply disturbance based management practices, using the same activities that created and maintained landscape heterogeneity in the past. However, the long-term and large-scale outcomes of these disturbances are often unknown, due to the complex response of Mediterranean vegetation to disturbance. Here we report on a spatially explicit, hybrid, and spatially hierarchical ecological model developed by us. The model attempts to predict the outcome of various disturbance based management activities on the long-term spatio-temporal dynamics of five common Mediterranean vegetation types. The model uses a spatially explicit state and transition formulation, with continuous transition functions. Model simulations were conducted on a Mediterranean landscape in Northern Israel, incorporating various disturbance practices that are common in the region. Simulation results highlight the potential of disturbance based management as a tool for conserving landscape heterogeneity, as well as the complex interactions between disturbances and the spatial structure of the landscape in Mediterranean regions.