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91.
Cover plants are one of the means to increase the functional biodiversity of fields and to enhance the ecological functions of the communities. However, the design of cropping systems including cover plants relies largely on expert knowledge. There is a lack of methods to select the best suited cover plants according to their role in the agrosystem. We propose to use functional traits to select cover plants suited to sustain ecological services in the banana agrosystems of the French West Indies. Our objectives were (i) to characterize a collection of cover plants on a trait basis, according to their potential to provide the services expected in a banana agrosystem and (ii) to discuss the potential use of this characterization for the design of innovative multi-species banana cropping systems. In these systems, four main services are targeted, i.e. controlling weeds, controlling plant-parasitic nematodes, improving soil fertility and particularly N availability, and avoiding competition with banana for resource acquisition. Three experiments were conducted, under field and controlled conditions, to evaluate the potential of a collection of 28 tropical cover plants to achieve the functions related to these services. For each cover plant, a functional profile was constructed from a combination of plant traits that are easy to assess experimentally. It described plants’ potential to achieve the functions expected in a banana agrosystem. Functional profiles required for cover plant usages were also identified. The comparison of the plant functional profiles and the functional profiles required for their usages enabled us to select the best suited plants for each usage. However, these functional profiles rarely corresponded, meaning that a cover plant is rarely sufficient to achieve all the functions required for a usage. Functional complementarities obtained by the mixture of different species of cover plants are thus often required. Compared to classical approaches of innovative cropping system design based on the experimental testing of spatial and temporal plant combinations, such a trait-based approach saves time by focusing on a shortlist of cover plants best suited according to their functions in the agrosystem. 相似文献
92.
秸秆袋装微贮饲料加工机械的研究 总被引:2,自引:0,他引:2
张本源 《农产品加工.学刊》2005,(2):67-68
秸秆袋装微贮饲料是一种营养价值高、采食和吸收率高、便于贮存和中长距离运输的饲料,是秸秆产业化的一项新技术。研究了商品化秸秆袋装微贮饲料加工机械,并提出了相应的饲料生产工艺。 相似文献
93.
为考察自行研制的南方双季稻区水田高留茬秸秆还田机大田作业效果,以原谷珍香为供试品种进行大田试验,并设置现有的常规秸秆还田机作业进行对照,通过对早稻不同高度的留茬秸秆进行还田作业,考察了该机具的耕作效果,并研究了对后茬晚稻机插质量、群体质量构建及产量和产量构成等指标的影响。结果显示,较对照,同一留茬高度时,经自行研制的南方双季稻区水田高留茬秸秆还田机处理的效果显著,其耕深、耕深稳定性、埋茬深度、耕后地面平整度和植被覆盖率分别平均提升5.18%、4.64%、20.85%、21.61%和4.43%,漏插率、漂秧率、伤秧率和翻倒率分别平均降低28.79%、23.17%、29.84%和45.02%,均匀度合格率和插秧深度合格率分别平均提高1.40%和1.65%,茎蘖数平均提高2.52%~6.62%,SPAD值(移栽后27 d始)平均提高3.59%~6.53%,地上部干物质重(插秧后34 d始)平均提高1.78%~4.81%,穗干重和收获指数分别平均提高3.39%和2.16%,有效穗、穗粒数、千粒重、结实率和理论产量分别平均提高2.52%、1.34%、0.08%、1.41%和5.47%,实际产量平均增产268.86 kg·hm-2,平均增产率4.09%。该机具对秸秆的留茬高度适应性强,作业效果好,适宜在南方双季稻区水田进行推广应用。 相似文献
94.
95.
真菌固态载体预处理对不灭菌玉米秸秆降解的影响 总被引:1,自引:0,他引:1
采用云芝变色栓菌(Trametes versicolor)、色精木霉菌(Trichoderma chromospermum)、深绿木霉菌(Trichoderma atroviride)和云芝变色栓菌分别与色精木霉菌、深绿木霉菌的混合菌对干黄玉米秸秆进行真菌预处理。结果显示,真菌预处理不灭菌秸秆30 d后,木质纤维素的降解率几乎可以忽略,在不灭菌的环境中,接入的真菌对秸秆本身附着的微生物群落不能形成竞争优势,造成较低的木质素降解率。而云芝变色栓菌、色精木霉菌、深绿木霉菌以及云芝变色栓菌分别与色精木霉菌、深绿木霉菌的混合菌对灭菌秸秆预处理30 d后,木质素的降解率分别为34.0%、38.1%、38.1%、39.1%及40.3%。为降低秸秆的灭菌成本,将真菌预处理30 d后的灭菌秸秆作为真菌固态载体与不灭菌秸秆按照1∶9、1∶4及1∶1的干质量比混合培养30 d,结果显示,采用云芝变色栓菌分别与色精木霉菌和深绿木霉菌的混合菌固态载体预处理不灭菌秸秆,木质素降解率可达到30%~40%。因而,真菌固态载体可以较好地适应非灭菌环境并对秸秆中的木质素进行有效降解,是一种有效降低过程成本的预处理手段。 相似文献
96.
研究旨在阐明云南文山州常用畜禽饲用秸秆的糖、蛋白和脂类养分的含量和综合等级,为该州饲用秸秆的养分评价和配置提供依据。以文山州近年广大畜禽养殖户常用的草果、‘西畴芭蕉芋’、‘文金1号’、‘文紫椒3号’、小米辣、滇重楼、象草和玉米‘文青贮2号’秸秆为材料,用分光光度法测定了秸秆的可溶性糖、总淀粉和可溶性蛋白质含量,用凯氏定氮法和索氏抽提法分别测定了粗蛋白和粗脂肪含量,并用隶属函数法评价了秸秆糖、蛋白和脂类养分的综合等级。结果表明:滇重楼秸秆的可溶性糖和可溶性蛋白质含量均最高,分别为163.603±0.218 mg/g(DW)和16.637±0.038 mg/g(DW),‘文青贮2号’秸秆的总淀粉和粗脂肪含量均最高,分别约为283.008±2.507 mg/g(DW)和(3.598±0.055)%,‘文紫椒3号’秸秆的粗蛋白含量最高,约为(11.864±0.202)%;可溶性糖、总淀粉、可溶性蛋白质、粗蛋白和粗脂肪含量在不同秸秆间的差异均达到极显著水平;8种秸秆糖、蛋白和脂类养分的综合等级为:滇重楼>‘文青贮2号’>小米辣>‘文紫椒3号’>西畴芭蕉芋>象草>‘文金1号’>草果。 相似文献
97.
围绕屋面覆盖秸秆空芯瓦的安装结构,设计了三种秸秆空芯瓦的安装工艺过程。阐述了秸秆空芯瓦具有重量轻、加工工艺精、颜色多种多样、安装方便、防渗漏性强、成本低廉等众多优点:,说明了固其具有节约资源、保护环境等优点,是今后屋面覆盖材料发展的重要方向。 相似文献
98.
在以小麦淀粉、玉米淀粉、马铃薯淀粉和可溶性淀粉为碳源代替葡萄糖为碳源的 MRS培养基上检测了菌株 L actobacillus amylophilus JCM112 5活菌数的增殖状况以及葡萄糖和有机酸的代谢特征同时测定了 p H值的变化。结果表明以淀粉为碳源时菌株先分解淀粉成葡萄糖并累积到一定数量后再加以利用 ;活菌数呈现双曲线增长现象 ;丙酮酸、乳酸、乙酸和柠檬酸及另一未知有机酸的数量发生了较大的变化。 相似文献
99.
Foliar fertilizers (FF) applied at the reproductive growth stage was reported to increase soybean (Glycine max L. Merr.) yield in field trials. But yield increases have not been consistent. Field experiments were conducted on Calloway silt loam soil in 1981—1982 to determine the effect of two foliar fertilizer (FF) formulations, 16N + 4P + 4K + 1 S (Hanway) and 12 N + 4 P + 4 K + 0.5 S (Folian), and time of application, 0800- and 1900-h, on the growth of seven soybean cultivars from maturity groups V, VI, and VII. Foliar fertilizers were applied at a rate of 187 L/ha?1 in water by a backpack CO2 pressure sprayer at R5 to R6 growth stages. Foliar fertilizers caused no crop injury (leaf burn) when applied at 1900-h but caused moderate injury at 0800-h, which caused a yield reduction. The most significant crop injury was caused by Hanway formulation when applied at 0800-h. Yields were significantly reduced by FF in 1981 but not in 1982. Generally, Folian formulation treatments had higher yields than Hanway formulation treatments, but neither formulation increased yield above that of the untreated plants. The Bragg cultivar exhibited the least amount of crop injury and the most positive yield response to FF. Plant height, 100-seed weight and lodging rates were not adversely affected by the foliar applications. Due to the general lack of consistent yield increases or in some instances yield reduction from FF applications, the formulations used cannot be recommended for use by soybean producers. 相似文献
100.
用新西兰引进的波纳、威诺阿、帕斯加、艾品、巴堪特和当地长期种植的芜菁6种冬春青绿饲料作物在云南省种羊场2个气候带种植,对各品种生物量及干鲜比进行比较分析.结果为芜菁生物量及含水量均较引进品种高;在引进品种中,高海拔山区威诺阿表现最佳,中海拔地区艾品较好. 相似文献