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361.
10a生连香树人工群落生物量研究 总被引:4,自引:0,他引:4
对10年(a)生连香树人工群落生物量的分布与模型及凋落物进行了研究,主要结果为:①建立了连香树各器官与地(胸)径或树高的回归模型68个.②群落总生物量(Wt/thm-2)为126.326,其中,地上和地下部分生物量(W/thm-2)分别为76.068和47.810,凋落物W为2.448.③群落、根系和吸收根的生产力(P/thm-2a-1)分别是12.388~15.248、4.781和0.611.④群落光能和有效光能利用率分别为0.75%和1.88%.⑤97.48%的根集中于0~20cm土层,69.93%的根分布于距干基40cm的水平范围;92.07%的叶分布于3~6m的垂直范围,83.80%的叶分布于距干基1m的水平范围;84.05%的干枝分布于距干基0.5m的水平范围.⑥10~12月凋落量占全年的81.26%.⑦凋落物对元素生物循环的影响大小顺序为P>N>K>Ca>Mg>Fe>Al>Mn.⑧提出了生物循环功能系数、凋落物分解率和保存率的算法及含义 相似文献
362.
生物膜反应器降解生物质气化洗焦废水 总被引:4,自引:1,他引:3
陶瓷球作为固定介质 ,接种本实验室保藏的Pseudomonassp1和Pseudomonassp2混合菌种 ,应用生物膜反应器处理生物质气化过程中产生的洗焦废水 ,对反应器运转整个过程的进出水COD浓度、进出水苯、萘、菲、吡啶、喹啉、异喹啉的含量、反应器内和反应器出水含菌量进行测定 ,以了解生物膜反应器处理生物质气化洗焦废水的特性 .结果表明 ,反应器经挂膜、增菌后 ,可达到稳定运转状态 ,有效的控制了反应器内微生物细胞的流失 ,使生物质气化洗焦废水中的有机物得到较好去除 . 相似文献
363.
陆源营养盐输入对青岛近岸海域DMS生物生产的影响 总被引:4,自引:1,他引:3
近海海域是全球DMS的重要排放源,同时近海海域,尤其是城市近岸海域是生态环境受人为干扰最为严重的区域.为了解人为活动对DMS生物生产的干扰,以青岛近岸海域为研究区域,在2001~2002年进行了不同季节的采样.发现该区域DMS存在季节变化,在生物量高的夏季,水体的DMS浓度也最高;高营养盐区域DMS/Chl a(单位叶绿素的DMS产量)低;低透明度区域DMS/Chl a也较低,且在长日照的夏季,透明度与DMS/Chl a有显著相关关系. 相似文献
364.
G. R. Rao J. V. N. S. Prasad B. M. K. Raju P. Sathi Reddy P. Sharath Kumar B. Venkateswarlu 《International Journal of Green Energy》2016,13(6):531-537
Jatropha curcas L. (Jatropha) is an important multipurpose tree valued for oil. In India, plans are underway to bring substantial area under this crop for meeting the biofuel requirements of the country. A study was conducted to develop allometric relationships in Jatropha to predict various biomass-related components (above ground and below ground) using easily measurable attributes, viz. collar diameter, tree height, number of branches, crown diameter, and crown depth. Further, it was aimed to establish the reliability of these relationships using an independent dataset obtained from varied management situations. Destructive sampling was carried out during the rainy season of 2011, when Jatropha plants were eight years old. Highly significant allometric relationships (F-values significant at 1% level) were obtained while predicting various biomass components (above, below, and total) using easily measurable attributes with R2 values ranging from 0.89 to 0.98. Of all the predictors, collar diameter exhibited a highly significant relationship with total dry biomass per plant (R2 = 0.97). The allometric relationships developed were validated with an independent dataset. The allometric relationships developed would serve as valuable tools for estimating total dry biomass production and carbon sequestration with reasonable accuracy in Jatropha systems, as they are proposed to be taken up in substantial area in the years to come. 相似文献
365.
366.
为了实现微藻培养基的低成本化和废水资源化利用多重目的的耦合,对反渗透浓缩液(RO浓水)作为培养基培养小球藻(Chlorella sp.)的可行性及其影响因素进行了探讨。实验取一级、二级处理出水和消化反应上清液及3种废水与RO浓水混合液制成6种培养基培养小球藻,探究最佳培养基;在此基础上探究浓度与温度对小球藻生长的影响。结果表明,培养15 d后,3种添加了RO浓水的培养基比3种纯废水培养基更有利于小球藻的生长,其中消化反应上清液-RO浓水混合液是最佳培养基;浓水浓度0%~90%的该混合液中小球藻生物量增加315%~780%,且小球藻的生物量表现为随RO浓水浓度的增大先增加后减小的变化趋势,30%是小球藻最佳培养浓度;在10、20和30℃下,浓度0%~90%的培养基中小球藻生物量增加了140%~570%,各浓度中的小球藻均在20℃下生长最好。 相似文献
367.
介绍了生物质直接燃烧发电技术原理及其设备的工作过程,着重讨论了生物质锅炉燃烧过程中的燃料收集和存储、送料堵塞以及受热面结焦等问题,并提出了优化运行和提高锅炉效率的改进措施。 相似文献
368.
生物质能源作为可再生能源的重要组成部分,其在替代能源、环境保护、减少碳排放,促进农民增效方面具有重要作用。以资源贫乏、能源短缺的湖北省作为生物质能源发展市场环境培育分析的研究对象,具有一定的代表性。通过深入分析生物质能源原料市场、产品市场、技术市场的发展现状,得知生物质能源发展的政策法规不完善、市场保障机制体系不健全、公众能源意识淡薄、投融资体制不顺畅、技术研发创新难是制约其产业发展的主要因素。因此对生物质能源发展的市场环境培育提出3方面建议:在政策法规层面,政府需要制定保护性政策来调控市场,以弥补市场力量的不足,并界定好生物质能源产业的发展方向;在监管体系层面,需要设立严格的生物质能源市场准入门槛和有效的定价机制,防止生物质能源过度发展;在企业经营层面,实施生物质能源企业集群带动战略,提升核心竞争力。 相似文献
369.
Michelan R Zimmer TR Rodrigues JA Ratusznei SM de Moraes D Zaiat M Foresti E 《Journal of environmental management》2009,90(3):1357-1364
The effect of flow type and rotor speed was investigated in a round-bottom reactor with 5 L useful volume containing 2.0 L of granular biomass. The reactor treated 2.0 L of synthetic wastewater with a concentration of 800 mgCOD/L in 8-h cycles at 30 degrees C. Five impellers, commonly used in biological processes, have been employed to this end, namely: a turbine and a paddle impeller with six-vertical-flat-blades, a turbine and a paddle impeller with six-45 degrees -inclined-flat-blades and a three-blade-helix impeller. Results showed that altering impeller type and rotor speed did not significantly affect system stability and performance. Average organic matter removal efficiency was about 84% for filtered samples, total volatile acids concentration was below 20 mgHAc/L and bicarbonate alkalinity a little less than 400 mgCaCO3/L for most of the investigated conditions. However, analysis of the first-order kinetic model constants showed that alteration in rotor speed resulted in an increase in the values of the kinetic constants (for instance, from 0.57 h(-1) at 50 rpm to 0.84 h(-1) at 75 rpm when the paddle impeller with six-45 degrees -inclined-flat-blades was used) and that axial flow in mechanically stirred reactors is preferable over radial-flow when the vertical-flat-blade impeller is compared to the inclined-flat-blade impeller (for instance at 75 rpm, from 0.52 h(-1) with the six-flat-blade-paddle impeller to 0.84 h(-1) with the six-45 degrees -inclined-flat-blade-paddle impeller), demonstrating that there is a rotor speed and an impeller type that maximize solid-liquid mass transfer in the reaction medium. Furthermore, power consumption studies in this reduced reactor volume showed that no high power transfer is required to improve mass transfer (less than 0.6 kW/10(3)m3). 相似文献
370.
Tensions between amenity- and timber-based economies in the U.S. and Canadian Pacific Northwest motivated a study of scenic beauty inside mature forests and timber harvests. A diverse sample of regional forests, measures of forest structure, and large, representative samples of photographs and public judges were employed to measure scenic beauty inside un-harvested mature and old-growth forests, and timber harvests. The latter varied systematically in down wood levels and retention level and pattern. Scenic beauty tended to be optimized at a basal area of 110–155 m3/ha and/or 700–900 trees/ha. Older forests and those with larger trees were perceived to be more beautiful. In harvests, greater retention levels, less down wood, and dispersed rather than aggregated retention patterns contributed to aesthetic improvements. Green-tree retention harvests offer considerable potential gains in perceived scenic beauty compared to perceived very ugly clearcuts, particularly at higher retention levels. These gains are more reliable from dispersed retention patterns. The silvicultural parameters studied change strength in affecting scenic beauty with changes in retention level. These interactions are explored in relation to a range of scenic quality objectives as an aid to planners, visual impact analysts, and silviculturists. 相似文献