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771.
为了解调节C/N比和添加复合菌剂对园林废弃物堆肥过程中有机物降解的动态变化和理化指标的影响,进行了不同处理措施的堆肥试验.结果表明,调节C/N比和添加复合菌剂有利于堆温的升高和有机质的分解,促进堆肥养分含量的增加,有利于全氮、有效氮及全钾的累积,但对全磷含量没有明显影响.表明调节C/N比和添加复合菌剂的处理措施比只调节C/N比更有利于堆肥的快速腐熟以及堆肥产品质量的提高. 相似文献
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The effect of feeding rate on the growth performance of green sturgeon (Acipenser medirostris) fry
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Four one‐week growth trials were conducted on green sturgeon fry to determine the effect of feeding rate on their growth performance at 18 °C when they were fed a salmonid soft moist feeds containing 445–457 g kg?1 of crude protein and 201–207 g kg?1 of lipid. The fry used in Trials I‐IV were 5–8 weeks after their initiation of exogenous feeding. Their average initial body weights were 1.63 ± 0.01, 2.63 ± 0.03, 5.08 ± 0.08 and 7.49 ± 0.05 g, respectively. Six feeding rates used were as follows: 2.5–15.0% body weight per day (% BW day?1) with a 2.5% increment in Trial I; 1.25–7.50% BW day?1 with a 1.25% increment in Trial II; and 2.0–7.0% BW day?1 with a 1.0% increment in Trials III and IV. Four replicates with 50 fry per tank in Trials I‐III and 30 fry per tank in Trial IV were assigned randomly to each feeding rates. The final body weight, specific growth rate, feed efficiency, protein retention, and whole‐body moisture, lipid, and energy contents were significantly (P < 0.05) affected by the feeding rates. The optimum feeding rates determined by the broken‐line model were 7.1, 5.7 and 5.3% BW day?1 for Trials I, II and IV, when the fry were 5, 6 and 8 weeks after their initiation of exogenous feeding, respectively. 相似文献
777.
Dryland wheat is the major contributor to wheat production in the world, where water deficiency and poor soil fertility are key factors limiting wheat grain yields and nutrient concentrations. A field experiment was carried out from June 2008 to June 2011 at Shilipu (latitude 35.12°N, longitude 107.45°E and altitude 1200 m above sea level) on the Loess Plateau (a typical dryland) in China, to investigate the effects of rotation with soybean (Glycine max) green manure (GM) on grain yield, total N and total Zn concentrations in subsequent wheat (Triticum aestivum L.), and on nitrate-N and available Zn in the soil. The benefits of crop rotation with soybean GM on wheat grain yields became more evident with time. In the second and third years, the grain yields of wheat rotated with soybean GM reached 4871 and 5089 kg ha−1 at the 108 kg N ha−1 rate. These yields were 21% and 12% higher than the highest yields of wheat under a fallow-winter wheat (FW) rotation. Rotation with soybean GM reduced the amount of N fertilizer required to obtain wheat grain yields and biomass levels similar to wheat grown in the FW rotation by 20–33%. In the first 2 years, average grain N concentrations over all N rates increased by 6% and 12%, and those of Zn increased by 26% and 14% under the soybean GM-winter wheat (SW) rotation, compared with the FW rotation. The increased grain N and Zn concentrations were found to be related to the increased concentrations of nitrate-N and available Zn in the soil, particularly at the sowing of winter wheat. However, grain N and Zn concentrations were not improved by rotation with soybean GM in the third year. This was attributed to the dilution effect caused by the more grain yield increase than its nutrient export. In conclusion, planting soybean for GM in fallow fields reduced the need for N fertilizer to enhance wheat yields in this dryland region. Change in wheat grain N and Zn concentrations was related to soil nutrient concentrations, and to the balance between increased grain yield and its nutrient export. 相似文献
778.
In view of the facts that existing evaluation standard for chinese green building is not meticulous, namely, most standard terms are qualitative, the quantification of standard terms is not reasonable and there are no weight differences between standard t 相似文献
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普洱茶提取物与绿茶提取物降糖功效的研究 总被引:2,自引:0,他引:2
通过整体动物模型研究比较普洱茶提取物与绿茶提取物的降糖功效。以C57BL/6J小鼠作为对照组,将遗传性糖尿病(KKAy)小鼠随机分组,分别灌胃给予普洱茶提取物与绿茶提取物4周,以空腹血糖、血糖曲线下面积作为观察指标,比较二者的药效作用;以SD雄性大鼠一次性腹腔注射链脲佐菌素(STZ)造模糖尿病大鼠,根据初始空腹血糖值随机进行分组,连续灌胃给予普洱茶提取物与绿茶提取物4周,以空腹血糖、血糖曲线下面积和空腹血清胰岛素作为观察指标。结果显示普洱茶提取物和绿茶提取物对KKAy小鼠和STZ糖尿病模型大鼠空腹血糖均有降低作用,同时均能降低血糖曲线下面积,但是不同的是普洱茶提取物在降低动物空腹血糖和血糖曲线下面积方面要优于绿茶提取物,同时普洱茶提取物能够较模型组显著降低大鼠空腹血清胰岛素,而绿茶提取物在降低大鼠空腹血清胰岛素与模型组相比无明显差异。比较了两种茶提取物对糖尿病的体外靶酶糖醛还原酶和PTP1B的抑制作用,发现普洱茶提取物对PTP1B活性有较强的抑制作用,抑制率88.0%,绿茶提取物对该酶无抑制作用。综合实验结果表明,普洱茶提取物的降糖功效优于绿茶提取物。 相似文献
780.
Aline Pissinatti Patricia Helena Santoro 《Communications in Soil Science and Plant Analysis》2018,49(13):1660-1670
The aim of this experiment was to test on-farm growing after composting the mixture of following legume plants Crotalaria juncea, Cajanus cajan, Mucuna aterrima with the grass Sorghum bicolor. The treatments were compared to commercial growing medium (CGM) and CGM+NPK to produce bedding plants of lettuce, broccoli, kale, and cabbage. The nutrient contents in CGM and CGM+NPK were higher than the values found in the mixture of the legumes plants with the grass. The pH was higher in the growing media from legume plants as well as the electrical conductivity in the combination CroSor and CajSor. The water retention capacity was higher in the treatments MucSor and CGM. The chemical attributes indicated that CroSor, CajSor, MucSor and CGM+NPK were better than CGM. The growing media from the mixture of legume with grass are an affordable alternative to produce bedding plants of lettuce, broccoli, kale and cabbage under organic agriculture system. 相似文献