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41.
Rose Luiza Moraes Tavares Zigomar Menezes de Souza Diego Silva Siqueira Newton La Scala Júnior Alan Rodrigo Panosso 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(8):755-762
Sugarcane management systems affect soil attributes such as the carbon cycle. This fact has stimulated the sugar and alcohol industry to refine the sugarcane production systems by replacing the pre-harvest burning (PB) and manual harvest with mechanized harvesting followed by residue deposition. The aim of this study was to evaluate different management systems with respect to C cycling carbon dioxide and soil parameters (chemical, physical and biological) which were determined over the season. Three sugarcane cultivation systems were evaluated at the following periods: (a) PB, (b) 5-year green harvest and (c) 10-year green harvest. The results indicated that CO2 emission was 36% greater in the 10-year sugarcane green harvest system than in the PB system. The bulk density and macroporosity were the factors that were most affected by the different sugarcane management systems and that significantly influenced soil CO2 emissions. The principal component analysis showed that soil CO2 emission was 18% influenced by base saturation (V%) and 14% by pH, especially in the PB area. Additionally, 19% was affected by carbon and macroporosity in the 5- and 10-year green harvest areas, respectively. From our results, it can be concluded that the most CO2 emissions are in the areas of sugarcane green, this is due to the higher carbon concentration when compared with the area of burning sugarcane. The parameters that most influenced the CO2 emissions were bulk density, porosity, macroporosity, pH and V%. 相似文献
42.
赵鹏 《湖南农业大学学报(自然科学版)》2013,39(5):458-462
为了明确烤烟不同生育期气候资源对烟叶品质的贡献率,以陕西安康烟区2002—2011年气象资料和烟叶化学成分为材料,采用主成分分析法,对烤烟不同生育期的平均温度、降水量和日照时数进行分析,构建不同生育期的气候综合指数(CCI);采用相关分析、通径分析和决策分析对各生育期CCI与烟叶化学成分的关系进行分析。结果表明:不同生育期CCI对烟碱含量的影响以采烤前期最大,旺长期最小,对采烤前期的影响主要为直接作用;对烟叶总糖含量的影响以采烤后期最大,采烤前期最小,对采烤后期的影响主要为直接作用和通过旺长期的间接作用;对烟叶糖碱比的影响以采烤后期最大,旺长期最小,采烤后期的影响主要为直接作用和通过采烤前期的间接作用。 相似文献
43.
采用超高效液相色谱-三重四级杆质谱(UPLC-MS/MS)建立厄贝沙坦及其复方制剂中N-亚硝基-N-甲基-4-氨基丁酸(NMBA)的测定方法。采用Waters ACQUITY UPLC○RHSS T3色谱柱进行分离,以0.005 mol/L甲酸铵(用甲酸调pH值至3.0)为流动相A,甲醇为流动相B,梯度洗脱,质谱检测器,流速为0.3 mL/min。结果显示NMBA的线性范围为0.156 6~3.132 6 ng/mL,相关系数r>0.99,方法检出限浓度为0.047 0 ng/mL(相当于样品浓度0.01μg/g),定量限浓度为0.156 6 ng/mL(相当于样品浓度0.03μg/g),样品加标回收率在80%~130%。说明该方法可以快速、简便、灵敏、准确地测定厄贝沙坦及其复方制剂中NMBA含量。 相似文献
44.
试验旨在研究复方中草药对猪生长性能、屠宰性能、肉品质和免疫功能的影响。将60头育肥猪随机分成4组,每组15头猪。对照组、Ⅰ组、Ⅱ组、Ⅲ组分别在基础日粮中添加0、0.5%、1.0%、2.0%的复方中草药。结果显示:与对照组相比,Ⅰ组育肥猪平均日增重、血清免疫球蛋白G(IgG)含量均显著提高(P<0.05),失水率显著降低(P<0.05)。与对照组相比,Ⅱ组、Ⅲ组育肥猪末重、平均日增重、胴体重、胴体斜长、熟肉率、脾脏指数、血清免疫球蛋白A (IgA)含量、IgG含量均显著提高(P<0.05),料重比、背膘厚、剪切力、失水率均显著降低(P<0.05)。与Ⅰ组相比,Ⅱ组、Ⅲ组育肥猪胴体重、胴体斜长、血清IgG含量均显著提高(P<0.05),背膘厚均显著降低(P<0.05)。研究表明,育肥猪基础饲粮中添加1.0%和2.0%的该复方中草药制剂均能改善育肥猪的生长性能、屠宰性能、肉品质和免疫功能,临床应用中选择1.0%作为最适添加剂量。 相似文献
45.
试验旨在研究不同剂量复合中草药添加剂对断奶仔猪生长性能的影响。选取84头(28±1)日龄、体重(8±0.5) kg的"杜×长×大"三元杂交断奶母仔猪,随机分成4组,每组3个重复,每个重复7头猪。试验1组饲喂基础日粮为对照组,试验2、3、4组分别添加2.0、2.5、3.0 g/kg的复合中草药添加剂。结果表明,试验3、4组仔猪平均日增重、平均日采食量显著高于试验1组(P<0.05);试验2、3、4组仔猪料重比、腹泻率显著低于试验1组(P<0.05)。试验3、4组仔猪的血清总蛋白、白蛋白含量显著高于试验1组(P<0.05);试验3、4仔猪血清尿素氮含量、谷丙转氨酶活性显著低于试验1组(P<0.05),试验4组仔猪血清碱性磷酸酶、过氧化氢酶活性显著高于试验1组(P<0.05)。试验4组仔猪血清免疫球蛋白G (IgG)、免疫球蛋白A (IgA)、补体C3、补体C4含量显著高于试验1组(P<0.05)。研究表明,日粮添加3.0 g/kg的复合中草药添加剂能有效提高断奶仔猪生长性能、调节代谢水平、增强免疫功能。 相似文献
46.
祁连山是我国西部重要的生态屏障,拥有大量的草地资源。研究草地土壤细菌群落组成及其与土壤环境因子间的关系,可对维持草地生态及了解祁连山土壤细菌群落组成提供一定的数据基础。采用高通量测序技术检测并分析了祁连山默勒镇3种类型草地 (高寒草甸、人工草地、沼泽化草甸)0~10 cm土壤细菌群落结构及多样性,并对上述土壤细菌群落与土壤理化因子的相关性进行了系统的研究。结果表明:1)沼泽化草甸土壤全氮、全磷、有机质碳、含水量和硝态氮显著高于高寒草甸和人工草地(P<0.05)。2)3地共测得有效序列1022446条,以97%的一致性将序列聚类,高寒草甸、人工草地、沼泽化草甸OTU聚类均值分别是4917、5233、5075条。3)Shannon和Simpson多样性指数3地间差异不显著,Chao1指数表现为人工草地>高寒草甸>沼泽化草甸(P<0.05)。4)在门水平上,3地均以变形菌门、酸杆菌门、放线菌门和浮霉菌门为主要类群;在属水平上,表现出不同类型草地细菌富集类型不同。5)有机质碳、全磷、土壤含水量与土壤细菌群落的组成表现出极显著相关(P<0.01)。综上,祁连山地区小生境内3种草地土壤微生物群落存在差异,有机质碳、全磷、土壤含水量是影响群落的主要驱动因子。 相似文献
47.
为研究不同利用方式对藏北高寒草甸建植一年生燕麦(Avena sativa Linn.)人工草地的土壤理化性质及土壤细菌群落的影响,本试验于8月份植物生长旺季,在持续利用人工草地(AG)、撂荒人工草地(AC)和对照天然草地(NG)采集土壤样品,分析了土壤理化性质、土壤细菌群落组成和结构特征变化。结果表明,AG样地土壤有机质、全钾含量和pH与NG样地相比无显著性变化,土壤全氮、速效氮和速效钾含量显著降低;AC样地与NG样地相比土壤pH显著升高,土壤有机质、全氮、速效氮和速效钾含量显著降低。AG样地土壤细菌群落Chao1,Shannon和Pielou均匀度指数显著高于NG样地,AC样地酸杆菌门和变形菌门丰度显著升高。土壤理化性质是土壤细菌群落结构组成门、属相对丰度变化主要影响因子。综上所述,高寒草甸一年生燕麦人工草地长期利用应科学补充肥料,保持土壤肥力;草地撂荒需谨慎,应及时采取恢复措施避免草地发生退化。 相似文献
48.
Mohammad Mijanur Rahman Khairiyah Mat Genki Ishigaki Ryo Akashi 《Animal Science Journal》2021,92(1):e13594
Year by year, huge quantities of by-products are generated during the manufacturing process of soybean-based products. Okara is one of the by-products, and it is an insoluble portion of the soybean. It consists of high moisture (8.4–22.9%); on dry matter basis, it contains high metabolizable energy (9.0–14.2 MJ/kg) and other components that include crude protein (20.9–39.1%), crude fiber (12.2–61.3%), crude fat (4.9–21.5%), and ash (3.4–5.3%). Fermentation of okara improves its nutritional quality and reduces its anti-nutrient contents. Due to animals' palatability, okara can be used to replace the soybean meal/concentrate feed partially or completely in ruminant's diet and partially in nonruminant's diet. Okara feeding does not depress the intake, digestibility, growth, milk production, blood metabolic profiles, and meat quality of animals. However, this by-product decays quickly due to its high moisture content, and its heavy weight and sticky nature make it difficult to process and expensive to dry using conventional methods. This paper thoroughly summarizes the utilization of okara as animal feed in the cause of developing a general guideline with favorable levels of inclusion in the diets of animals for its exploitation and valorization. This review will encourage further research to develop eco-friendly and value added feed for animals. 相似文献
49.
JIANG Ling-ling CHEN Hong-yu SHI Kai-zhi ZHOU Si-xuan YU Bo BU Shi-jin 《中国畜牧兽医》2016,43(11):3073-3079
In order to understand the security of a new kind of antidiarrheal Chinese herbal medicine compound preparation for livestock,acute and sub-chronic toxicity test were conducted.Acute toxicity test used the largest drug dose method,20 Wistar rats were orally treated with the Chinese medicine compound preparation.In the sub-chronic toxicity test,80 rats were randomly divided into 4 groups with 20 rats in each group and orally given a dose of 3 000,1 500,750 and 0 mg/(kg·BW)of Chinese medicine compound preparation once a day for 30 days.The general clinical status was observed,rats weight were measured and the dose was adjusted every week during the test,after the test measured blood routine index,biochemistry index,and preceded the gross anatomy observation,weighing each major organs and calculated the viscera coefficient,and proceded main viscera histopathological observation between the high dose group and the control group.The acute toxicity results showed that every rat would be alive gavaged with the lethal dose(LD50)of compound preparation larger 5 g/(kg·BW).The sub-chronic toxicity autopsy showed that except heart,lung,and testicles in individual rats appeared mild bleeding in the high dose group,the other dose group organs found no abnormal change.The haematological index showed except mononuclear cell rate(P<0.05),and hematocrit declined significantly(P<0.05)in the high dose group,all the indexes of the other groups were in the normal range,there was no significant difference from the control group.The test suggested the Chinese medicine compound preparation was no toxicity under the condition of this test according to acute toxicity classification standard of exogenous chemicals by WTO,there was no effect on the growth and development of rats in the sub-chronic toxicity test,and there was no chronic toxicity at least 1 500 mg/kg feeding conditions in short-term repeated application. 相似文献
50.
The effect of lactic acid bacterial starter culture and chemical additives on wilted rice straw silage 下载免费PDF全文
Yan‐Su Wang Wei Shi Lin‐Ting Huang Cheng‐Long Ding Chuan‐Chao Dai 《Animal Science Journal》2016,87(4):525-535
Lactic acid bacteria (LAB) are suitable for rice straw silage fermentation, but have been studied rarely, and rice straw as raw material for ensiling is difficult because of its disadvantages, such as low nutrition for microbial activities and low abundances of natural populations of LAB. So we investigated the effect of application of LAB and chemical additives on the fermentation quality and microbial community of wilted rice straw silage. Treatment with chemical additives increased the concentrations of crude protein (CP), water soluble carbohydrate (WSC), acetic acid and lactic acid, reduced the concentrations of acid detergent fiber (ADF) and neutral detergent fiber (NDF), but did not effectively inhibit the growth of spoilage organisms. Inoculation with LABs did not improve the nutritional value of the silage because of poor growth of LABs in wilted rice straw. Inoculation with LAB and addition of chemical materials improved the quality of silage similar to the effects of addition of chemical materials alone. Growth of aerobic and facultatively anaerobic bacteria was inhibited by this mixed treatment and the LAB gradually dominated the microbial community. In summary, the fermentation quality of wilted rice straw silage had improved by addition of LAB and chemical materials. 相似文献