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Many retailers take initiatives to reduce food waste, which can lead to enhanced sustainability, including reduced environmental impacts and cost savings. Another common environmental strategy in retail management is to increase the range of organic products. This study examined if organic food products have a higher level of waste, which thereby risk to counteract the environmental ambitions behind offering these products. The study also examined to what degree differences in waste level could be explained by turnover, shelf-life and wholesale pack size. In the study, six Swedish supermarkets provided data on all articles sold or wasted in the deli, meat, dairy and cheese departments during 2010 and 2011. 24 organic products were compared to their conventional counterparts; 22 of these had higher waste levels (from 1.5 to 29 times higher). Differences in wastage were also compared across departments; in all four departments, organic products as a group had higher waste percentage at all four departments. There was a negative correlation between the total mass sold of a product and the percentage waste. Also, longer shelf-life was associated with decreased waste, but only for products with low turnover. The systematic problem of retail food waste – particularly of organic products and other products with a low turnover – may be mitigated by increasing turnover, by stocking products with longer shelf-life or by decreasing the ordered volume (e.g. through decreased wholesale pack sizes). 相似文献
413.
在植物粮食、土壤有机氯农药残留监测,使用涂有OV-17和QF-1固定液的白色载体ChromosorbW,该种色谱柱对六六六的四种异构体分离比较好,但对DDT的四种异构体分离不理想,采用红色载体ChromosorbP和白色载体ChomosorbW湿床填充的色谱柱,分离有机氯农药8种组份仅需15分钟,提高了有机氯农药的分离分析效果。 相似文献
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重庆电厂炉前煤及飞灰中As元素在有机酸作用下的淋滤行为 总被引:3,自引:0,他引:3
采用模拟酸雨手段,突出有机酸对As元素的淋出作用。分别配置pH=4.47的硝酸、乙酸及硝酸与乙酸的混酸三种淋滤液,对重庆电厂炉前煤及飞灰中的As元素进行40h的淋滤实验,以探讨有机酸淋滤条件下As元素的淋出行为。结果表明:有机酸淋滤液对炉前煤及飞灰中的As元素具有较强的淋出作用,有机酸中H^+的缓冲释放作用是导致As元素较强淋出率的主要因素。 相似文献
416.
Steven Kragten Krijn B. Trimbos Geert R. de Snoo 《Agriculture, ecosystems & environment》2008,126(3-4):163-167
The aim of this study was to analyse the effects of differences in cropping pattern between organic and conventional arable farms on the breeding activity of skylarks and to assess the effects of arable crop management on skylark nest survival. Skylark nest density was seven times higher on organic farms than on conventional farms (0.63 vs. 0.09 nest per 10 ha). Skylarks showed a strong preference for spring cereals, lucerne and grass leys, all of which were mainly or exclusively grown on organic farms. On organic farms nests were initiated during the entire breeding season, but on conventional farms no nesting activity was found during the peak of the season (early May to early June). On organic farms 27% of all nests was successful. Increasing the availability of suitable breeding habitat during the peak of the breeding season on conventional farms might provide one means of enhancing breeding skylark populations. On organic farms, crop management should focus on reducing nest loss due to farming operations. 相似文献
417.
城市污水一级半处理方法的研究 总被引:5,自引:0,他引:5
本文提出了用高负荷生物接触氧化法对城市污水进行一级半处理的方法。采用软性填料接触氧化池处理模拟城市污水的合成污水,在负荷为10—25kgCOD/m~3·d时,有机物去除率为60%—70%,处理程度介于一级与二级处理之间,相当于一级半处理。一级半处理方法可使有机物去除速度大大增加,同时获得含能量较大的生物污泥,为消化产气、能量回收创造条件。 相似文献
418.
本文测定了几种有机污染物在双组分有机相与水相之间的分配系数,结果显示污染物在这种两相体系间的分配系数与构成有机相的两种有机溶剂对污染物的萃取常数及体积份数有关,并对污染物在有机相存在分子缔合时的分配行为进行了探讨. 相似文献
419.
为探究锌(Zn)污染对农田土壤氧化亚氮(N2O)排放的影响,分别以猪粪和尿素为肥源进行室内培养实验,对比分析不同含量Zn (0、50、500、1500和5000mg/kg)对N2O排放的影响及其机制,并在培养第52d向所有处理再次添加尿素以探究其长期效应,共培养80d.结果表明:第1次添加肥料阶段,在尿素为肥源处理中不同含量Zn均表现为显著抑制作用(P<0.05),而猪粪为肥源处理中除50mg/kg无显著影响外(P>0.05),其它含量处理均显著促进N2O排放(P<0.05).第2次添加肥料阶段,不同肥源条件下Zn的作用规律一致,即50mg/kg无显著影响(P>0.05),500和1500mg/kg显著提高N2O排放而5000mg/kg处理与之相反(P<0.05).此阶段500、1500和5000mg/kg处理以猪粪和尿素为肥源时其N2O累积排放量与同肥源对照的比值分别为3.49、3.13、0.01和2.53、2.74、0.04,可见同等含量Zn在猪粪为肥源条件下作用更强,500和1500mg/kg Zn的促进机制为Zn提高了土壤中NH4+-N、NO3--N含量以及控制反硝化过程N2O产生和还原功能基因相对丰度的比值(nirS/nosZ),而5000mg/kg Zn抑制了土壤中NH4+-N进一步转化为NO3--N,从而降低了N2O排放. 相似文献
420.