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261.
为研究不同堆肥对南方屋顶绿化植物生长的适应性,探索不同堆肥对混合栽培基质的改良效果,本研究采用5因素4水平正交实验法,以3种堆肥、椰糠、珍珠岩和草炭为基质,以早熟禾、四季海棠、佛甲草和彩叶草为供试植物,通过观测植物株高、叶片叶绿素含量、净光合速率和蒸腾速率的变化规律,以及添加不同堆肥混合栽培基质对植物生理生长特性的影响,研制出了适用于南方屋顶绿化栽培的最佳组合配方。结果表明,最适宜南方屋顶绿化混合栽培基质的配方为A2B2C3D2,即四季海棠、园林废弃物堆肥4份、椰糠添加量1份、珍珠岩添加量4份,与本实验处理6最接近。该研究对合理配制混合栽培基质,提高南方屋顶绿化栽培的成功率提供了一定的理论和实践依据。 相似文献
262.
263.
George F. Antonious Eric T. Turley Regina R. Hill 《Journal of environmental science and health. Part. B》2013,48(5):361-365
Composting and land application of municipal sewage sludge (SS) and yard waste (YW) compost are increasingly popular ways for using organic waste as a source of organic matter, while decreasing the amount of waste being diverted into landfills. Researchers have largely ignored the effect of SS and SS mixed with YW (SS+YW) compost on the antioxidant contents of vegetables grown under this practice. Accordingly, the main objective of this investigation was to monitor the impact of SS and SS+YW on the nutritional composition of pepper and melon fruits at harvest. Total phenols and ascorbic acid contents of pepper and melons (determined by the Folin-Ciocalteau and the dichlorophenol–indophenol methods, respectively) were greater in pepper than melon fruits. Soil amended with SS or SS+YW significantly elevated the concentrations of ascorbic acid and total phenols in melon fruits compared to no-mulch native soil. The application of SS did not modify the concentration of β-carotene in melon fruits at three harvests. Regardless of soil treatments, ascorbic acid and total phenols concentrations were greater in melon fruits collected at the first harvest compared to harvest three. Pepper fruits collected at harvest three contained the greatest concentrations of ascorbic acid and total phenols; whereas, pepper fruits collected at the second harvest contained the greatest concentrations of soluble sugars. 相似文献
264.
265.
为了对不同比例的二丁与连翘药渣堆肥腐熟度进行评价,采用条垛式好氧堆肥方式,将二丁和连翘两种药渣按照5种不同的比例进行堆肥处理,通过分析堆肥过程中温度、pH、C/N和发芽指数等指标的变化规律,对堆肥腐熟度进行评价。结果表明:在试验处理条件下及堆肥周期内,单一药渣堆肥的两组处理未能完全腐熟,混合药渣堆肥的3组处理均已达到完全腐熟的标准,说明两种药渣混合后进行堆肥,可以有效促进堆肥的顺利进行,且二丁与连翘比例为2∶1(质量比)时发酵效果最好。3组混合药渣的发酵产物可以作为有机肥或土壤改良剂施用,也可以与化肥配合,制备成有机/无机配方肥。 相似文献
266.
267.
嗜热真菌的生物转化功能与经济价值 总被引:5,自引:0,他引:5
嗜热真菌是经济微生物中极为重要的一个类群,许多兼性嗜热真菌可在常温和一般高温条件下生存,它们在有机物质的生物转化和物质循环中起着重要的作用。对嗜热真菌在蘑菇培养料的制备、废物的堆肥化处理、酒曲制作等几种常见生产过程中的生物转化作用和机理进行分析,探讨嗜热真菌在人类生产活动中的作用及经济价值。 相似文献
268.
城市生活垃圾的堆肥研究 总被引:1,自引:0,他引:1
城市生活垃圾经动态式堆肥翻堆机处理制成腐熟堆肥,并最终试制成有机复混颗粒肥,二者先后在茶树、数种花卉作物和数种叶菜类蔬菜上进行田间试验,证明有较好的肥效,且成本较低廉,在农业生产上有实际应用的价值。从环境保护角度上看:这种方法是将城市生活垃圾转化为资源化、无害化的一项有意义的举措。 相似文献
269.
Biodegradation behavior and material properties of aliphatic/aromatic polyesters of commercial importance 总被引:2,自引:0,他引:2
Uwe Witt Rolf- Joachim Müller Wolf- Dieter Deckwer 《Journal of Polymers and the Environment》1997,5(2):81-89
Copolyesters of aliphatic monomers with a defined amount of terephthalic acid recently have been shown to be biodegradable.
This group of plastic materials exhibits very interesting material properties with regard to their technical application potential.
A tensile strength of 25 N/mm2 combined with elongations at break up to 1500% was achieved for BTA materials. Melting points varied from 80 to 140‡C. Biodegradation
rate under compositing conditions were determined, showing typical erosion rates of films, in the range of 5 to 10 Μm/week.
The material properties and the degradation rate as well can be adjusted by the copolymer composition. Stretching of the polymer
in the cold state leads to 10-fold higher mechanical strength of the material. The polyester chain can be extended to high
molar masses, resulting in melt viscosities suitable, e.g., for melt below extrusion. 相似文献
270.
Effect of Poly(Vinyl Alcohol) and Polyethylene on the Growth of Red Pepper and Tomato 总被引:2,自引:0,他引:2
Poly(vinyl alcohol) (PVA) and polyethylene (PE) were blended with a soil for cultivation, and their effects were investigated on the growth behavior of red pepper and tomato by examining the stems, the leaves, and the roots. PVA retarded the growth of red pepper significantly even at a concentration as low as 0.05%. The roots were depauperated more than the stems and the leaves. Tomato was also affected by PVA but to a lesser extent than red pepper. In contrast, the presence of both round pieces (10 mm diameter) of PE film and powdery PE influenced negligibly the growth of red pepper as well as that of tomato up to 35 wt% in soil. 相似文献