Nitrogen fertility and abiotic stresses management in cotton crop: a review

This review outlines nitrogen (N) responses in crop production and potential management decisions to ameliorate abiotic stresses for better crop production. N is a primary constituent of the nucleotides and proteins that are essential for life. Production and application of N fertilizers consume huge amounts of energy, and excess is detrimental to the environment. Therefore, increasing plant N use efficiency (NUE) is important for the development of sustainable agriculture. NUE has a key role in crop yield and can be enhanced by controlling loss of fertilizers by application of humic acid and natural polymers (hydrogels), having high water-holding capacity which can improve plant performance under field conditions. Abiotic stresses such as waterlogging, drought, heat, and salinity are the major limitations for successful crop production. Therefore, integrated management approaches such as addition of aminoethoxyvinylglycine (AVG), the film antitranspirant (di-1-p-menthene and pinolene) nutrients, hydrogels, and phytohormones may provide novel approaches to improve plant tolerance against abiotic stress-induced damage. Moreover, for plant breeders and molecular biologists, it is a challenge to develop cotton cultivars that can tolerate plant abiotic stresses while having high potential NUE for the future.     

基于HJ卫星混合像元分解法的湖北省四湖地区夏收作物种植信息提取

混合像元是造成中低空间分辨率遥感数据计算机解译不准确的主要原因，通过收集2013年四湖地区夏收作物生长期内的不用生育时期的三景HJ卫星CCD数据，生成一个15波段的“类高光谱”数据；在采用阀门技术结合夏收作物NDVI指数变化特点，提取所有夏收作物（小麦与油菜）在四湖地区的空间分布的基础上，成功运用改进的逐步回归法计算出小麦与油菜在混合像元中的丰度值，高精度地取得了四湖地区小麦、油菜种植区的空间分布；将部分结果与同期资源三号卫星融合数据作为标准进行比较，证明基于改进的逐步回归法计算混合像元的丰度值是比较准确的，为运用HJ卫星CCD数据高精度提取农作物种植信息提供了一种可行的方法     

铜绿微囊藻吸附废水中镍离子的研究

生物吸附法治理重金属废水为目前的一个研究热点。本文以铜绿微囊藻为研究对象,考察铜绿微囊藻藻液和藻粉对重金属镍离子的吸附效果。原子吸收光谱结果表明:藻液和藻粉的去除率分别为23.6%和92%,藻粉相比于藻液有更好的处理效果。傅里叶红外光谱(FTIR)及扫描电镜(SEM)结果表明:吸附重金属后,两者的峰型大致一致,藻粉和藻液的空间结构均发生了明显的改变。上述研究结果证明铜绿微囊藻可以作为一种去除重金属的生物吸附剂,为后续藻类治理重金属污染奠定了理论基础。     

Causes of decreased reference evapotranspiration and pan evaporation in the Jinghe River catchment, northern China

This study focused on the changes of reference evapotranspiration (ET₀) and pan evaporation (ET_pan) to study the impacts of climate change on the hydrological cycle in the Jinghe River catchment. Based on the Penman–Monteith equation, the ET₀ was calculated. The temporal trend and spatial distribution of ET₀ and E_pan measured with a 20-cm pan were examined at the 14 stations during 1957–2005. The effects of meteorological factors on the variation of ET₀ were determined by analyzing the trends in themselves with comparison between original climate and detrended climate scenarios and then their sensitivity to ET₀. Both the ET₀ and E_pan showed remarkable decreasing trends from 1957 to 2005 and their decreasing rate was 40.9 and 17.7 mm per 10 years, respectively. Trend analysis of meteorological factors exhibited that the reduction in ET₀ and ET_pan was principally caused by both significant decreases in wind speed and sunshine hours. Furthermore, the decreasing trend of ET₀ was mainly dominated by the significant decrease in wind speed with high sensitivity, to a less extent, by the decrease in net radiation. Although relative humidity is one of the most sensitive variables, its effect on ET₀ was negligible because of its temporal constancy. The contribution of wind speed reduction to decreased ET₀ has increased from 50 to 76.1%, but net radiation, by contrast, decreased from 50 to 23.9%.     

Using diatom indices for water quality assessment in a subtropical river, China

Diatoms have been regularly used as bioindicators to assess water quality of surface waters. However, diatom-based indices developed for a specific geographic region may not be appropriate elsewhere. We sampled benthic diatom assemblages in the upper Han River, a subtropical river in China, to evaluate applicability of 14 diatom-based indices used worldwide for water quality assessment. A total of 194 taxa from 31 genera were identified in the dry season and 139 taxa from 23 genera in the wet season. During the dry season, significant relationships were found for all but one of the diatom-based indices (Index Diatom Artois–Picardie) with one or more physical and chemical variables including nutrients and ion concentrations in river waters. The Biological Diatom Index (IBD) and diatom-based eutrophication/pollution index (EPI-D) were strongly related to trophic status and ionic content, while Watanabe’s Index was related to organic pollution and conductivity. Yet, the diatom indices showed weak relationships with physical and chemical variables during the wet season. It suggests that diatom-based indices developed in Europe can be applied with confidence as bioindicators of water quality in subtropical rivers of China, at least during base-flow conditions.     

Characterization of titanium oxide optical band gap produced from leachate sludge treatment with titanium tetrachloride

Environmental Science and Pollution Research - This study investigated the coagulation performance of titanium tetrachloride (TiCl4) for leachate treatment and preparation of titanium oxide (TiO2)...     

An improved method used for evaluating potential environmental pollution risk based on spatial distribution and density of farms

Environmental Science and Pollution Research - The livestock manure nitrogen load on farmland (LMNLF) is often used to assess the potential environmental pollution risk of livestock manure nitrogen...     

The interaction effects of FEN1 rs174538 polymorphism and polycyclic aromatic hydrocarbon exposure on damage in exon 19 and 21 of EGFR gene in coke oven workers

Polycyclic aromatic hydrocarbon (PAH) exposure and genetic susceptibility were conductive to genotoxic effects including gene damage, which can increase mutational probability. We aimed to explore the dose-effect associations of PAH exposure with damage of exons of epidermal growth factor receptor (EGFR) and breast cancer susceptibility gene 1 (BRCA1), as well as their associations whether modified by Flap endonuclease 1 (FEN1) genotype. Two hundred eighty-eight coke oven male workers were recruited, and we detected the concentration of 1-hydroxypyrene (1-OH-pyr) as PAH exposure biomarker in urine and examined base modification in exons of EGFR and BRCA1 respectively, and genotyped FEN1 rs174538 polymorphism in plasma. We found that the damage indexes of exon 19 and 21 of EGFR (EGFR-19 and EGFR-21) were both significantly associated with increased urinary 1-OH-pyr (both P_trend < 0.001). The levels of urinary 1-OH-pyr were both significantly associated with increased EGFR-19 and EGFR-21 in both smokers and nonsmokers (both P < 0.001). Additionally, we observed that the urinary 1-OH-pyr concentrations were linearly associated with both EGFR-19 and EGFR-21 only in rs174538 GA+AA genotype carriers (both P < 0.001). Moreover, FEN1rs rs174538 showed modifying effects on the associations of urinary 1-OH-pyr with EGFR-19 and EGFR-21 (both P_interaction < 0.05). Our findings revealed the linear dose-effect association between exon damage of EGFR and PAH exposure and highlight differences in genetic contributions to exon damage and have the potential to identify at-risk subpopulations who are susceptible to adverse health effects induced by PAH exposure.

     

利用废旧锌锰电池制备光催化剂净化甲苯

针对废旧锌锰电池回收利用难,以及光催化剂 TiO2活性低的问题,以废旧锌锰电池和商业二氧化钛为原料,通过球磨法制备了新型复合光催化剂.在紫外光灯照射下,进行了废旧锌锰电池复合改性TiO2对甲苯的光催化氧化实验,并重点探究空速、光照强度、相对湿度和氧气体积分数等关键实验条件对甲苯净化效率的影响.结果表明,改性后的催化剂对甲苯的净化能力大幅提高;当TiO2与废电池芯粉的质量比为2:1时,催化剂的催化效果最好,甲苯的净化效率提高了近45％;空速越大,催化剂对甲苯的净化效率越低;净化效率随光照强度的增加呈现先增加后保持不变的规律;催化剂在相对湿度为30％的条件下具有最佳的催化活性,氧气体积分数为15％时为净化效率达到最大.本研究结果可为废旧锌锰电池的回收利用提供新的思路.     

NO2 catalytic formation,consumption, and efflux in various types of diesel particulate filter

Environmental Science and Pollution Research - The high NO2/NOX ratio in the after-treatment system is beneficial to its performance and achieved by NO catalytic conversion in diesel oxidation...