天津市产业碳排放的影响因素及贡献     

江文渊  曾珍香  张征云 《水土保持通报》2020,40(5):152-159

[目的] 综合考虑“水—土—能—碳”相互关系，研究产业碳排放的影响因素及贡献，为天津市减排决策制定提供一定依据。[方法] 对天津市产业碳排放进行测算，将水土资源因素引入Kaya恒等式，运用LMDI模型计算产业碳排放各影响因素的贡献。[结果] 2004—2018年天津市各产业碳排放均呈现上升趋势；整体来看，水资源经济产出、人口数量促进天津市各产业碳排放，且前者为主要促进因素，水土资源因素抑制各产业碳排放，碳排放强度促进农业碳排放，而抑制其他产业碳排放，人均用地面积抑制农业碳排放，而促进其他产业碳排放；水土资源因素对各产业碳排放影响的变化与水土资源匹配度变化有较好的一致性，单位用地面积用水量越多，其对碳排放的促进作用越大。[结论] 为实现节能减排，应发展节水产业，优化城市水土资源开发利用，发挥水土资源因素对碳排放的抑制作用。  相似文献   

浅圆仓膜下氮气气调膜上控温储粮试验     

董晓欢  黄俊熹  彭朝兴 《粮食储藏》2017,(4):32-35

通过改造浅圆仓测温电缆,实现了浅圆仓膜下充氮气调和膜上中央空调控温,提高了卸粮口、大门口、通风口等死角的害虫致死率。将浅圆仓氮气气调杀虫与控温储粮相结合,实现了储粮安全度夏。  相似文献   

Effects of cover crop growth and decomposition on the distribution of aggregate size fractions and soil microbial carbon dynamics          下载免费PDF全文

D. Linsler  M. Kaiser  R. Andruschkewitsch  C. Piegholdt  B. Ludwig 《Soil Use and Management》2016,32(2):192-199

Although the effects of cover crops (CC) on various soil parameters have been fully investigated, less is known about the impacts at different stages in CC cultivation. The objective of this study was to quantify the influence of CC cultivation stages and residue placement on aggregates and microbial carbon (C_mic). Additionally, the influence of residue location and crop species on CO₂ emissions and leached mineralized nitrogen (N_min) during the plant degradation period was also investigated. Within an incubation experiment, four CC species were sown in soil columns, with additional columns being kept plant‐free. After plant growth, the columns were frozen (as occurs in winter under field conditions) and then incubated with the plant material either incorporated or surface‐applied. With CC, concentrations of large and medium macroaggregates were twice that of the fallow, confirming positive effects of root growth. Freezing led to a decrease in these aggregate size classes. In the subsequent incubation, the large macroaggregates decreased far more in the samples with CC than in the fallow, leading to similar aggregate size distributions. No difference in C_mic concentration was found among the CC cultivation stages. CO₂ emissions were roughly equivalent to the carbon amounts added as plant residues. Comparison of columns with incorporated or surface‐applied residues indicated no consistent pattern of aggregate distribution, CO₂ emission or C_mic and N_min concentrations. Our results suggest that positive effects of CC cultivation are only short term and that a large amount of organic material in the soil could have a greater influence than CC cultivation.  相似文献   

半地下带保温夹套发酵罐的应用     

刘佃林 《现代农业科技》2011,(6):257-258

通过对半地下带保温夹套的发酵罐与普通发酵罐24 h的温度变化和6 d的产气量的对比试验分析,结果表明:采用半地下带保温夹套发酵罐发酵,24 h的温度变化缓慢,受外界温度变化影响小,高温持续的时间较长,利于微生物发酵;产气总量多,持续时间长。  相似文献   

木薯渣与甜菜颗粒粕组合效应对奶牛瘤胃发酵特性的影响     

郑宇慧  张新雨  李胜利 《中国畜牧杂志》2021,(2):130-136

本试验旨在通过体外产气法研究木薯渣与甜菜颗粒粕组合用作泌乳中后期奶牛饲料的可行性及适宜组合比例。试验设计7个处理:木薯渣分别以0%(对照组)、5%、10%、15%、20%、25%和30%与甜菜颗粒粕(风干物质基础)组合,使用AGRS-Ⅲ型微生物发酵产气系统进行体外瘤胃微生物发酵试验,监测体外培养3、6、12、24、48h后的发酵液pH、氨态氮(NH3-N)、微生物蛋白(MCP)含量和体外培养48h后干物质消失率(IVDMD)、累积产气量(GP)及挥发性脂肪酸(VFA)含量等指标。结果表明:体外培养48 h后,GP和底物的最大降解率(RmaxS)随木薯渣占比增加呈线性或二次增加(P<0.05);发酵液各VFA和TVFA含量均随木薯渣占比增加呈线性或二次降低(P<0.05);根据多项组合效应值,以0%组为对照时,5%组和10%组表现为正组合效应,其余组合均表现为负组合效应。在本试验条件下,当木薯渣与甜菜颗粒粕组合使用,且木薯渣为5%~10%较为适宜,但此结果仍需奶牛饲养试验进一步验证。  相似文献   

Chemical and nutritional characteristics of Cannabis sativa L. co-products     

Alessandro Vastolo  Serena Calabrò  Severina Pacifico  Bossima Ivan Koura  Monica Isabella Cutrignelli 《Journal of animal physiology and animal nutrition》2021,105(Z1):1-9

Cannabis sativa L. is an annual herbaceous plant. It was used for centuries to obtain different products. In the last century, hemp cultivation was forbidden due to the psychoactive effects of tetrahydrocannabinol acid (THCA). In the last years, new strains, characterized by high cannabidiolic acid (CBDA) and low THCA level, were developed renewing the interest in hemp cultivation to obtain food or to extract essential oils from flowers. All these processes produce many residues with different chemical–physical characteristics. In order to evaluate their potential use also in animal nutrition, some hemp co-products were evaluated. Two different co-products of seed processes (flour and oil) and two co-products obtained trimming the flowers, differing in granulometry were used. The samples were analysed for chemical composition and evaluated in vitro using the gas production technique with buffaloes' ruminal inoculum. All hemp co-products showed interesting nutritional characteristics, such as crude protein content always higher than 20% on a dry matter basis, and high neutral detergent fibre concentration partially lignified. The in vitro gas production parameters at 120 h of incubation showed quite low fermentability testified by the low organic matter degradability and cumulative gas volume (OMD from 28.09 to 45.64% and OMCV from 110 to 164 ml/g, respectively). Also, the methane produced after 24 h of incubation was particularly low (from 1.78 to 11.73 ml/g dOM). These results could be due to the high lipid and ash amounts or to the CBDA content that probably affected the CH₄ formation processes. According to preliminary results obtained by this study, it is possible to hypothesize that these co-products could be useful to mitigate the methane production into the rumen. Further studies are necessary in order to evaluate the correct inclusion into the diet for ruminants.  相似文献   

一种利用气相色谱快速检测瘤胃体外发酵液中三甲胺浓度的方法     

周阳  金巍  向小娥  成艳芬  朱伟云 《动物营养学报》2021,33(1)

本试验旨在建立一种利用气相色谱快速检测瘤胃体外发酵液中三甲胺浓度的方法。瘤胃体外发酵试验设置2个组,对照组(n=4)和试验组(n=4),试验组每个发酵瓶中添加0.0414 g三甲胺盐酸盐,发酵24 h。采用10 mol/L氢氧化钾溶液对发酵液样品进行预处理,使用WEL-PEG20M色谱柱和氢火焰离子检测器对三甲胺进行分离和检测。利用无三甲胺背景值的发酵培养基上清液配制不同浓度的三甲胺标准液,制备标准曲线。结果显示:三甲胺的标准曲线在0.1~1.0 mg/mL之间具有较好的线性关系(R 2≥0.993),平均回收率为98.44%~100.27%,三甲胺的最低检出限为0.01 mg/mL。对照组0和24 h发酵液均未检出三甲胺。试验组0 h发酵液三甲胺浓度为0.65 mg/mL,24 h发酵液三甲胺浓度为0.12 mg/mL,说明三甲胺被瘤胃微生物大量利用。综上所述,本试验建立的三甲胺检测方法操作步骤简单,准确度和灵敏度相对较高,能够快速准确监测发酵液中三甲胺浓度的变化,为瘤胃微生物三甲胺代谢研究提供了快捷高效的检测方法。  相似文献   

奶牛场温室气体排放与减排措施     

郑永辉  鞠鑫鑫  孙辉  郭建斌  董仁杰 《中国乳业》2021,(11):34-39

奶牛养殖在产能提升的同时也排放了大量温室气体。本文梳理了奶牛养殖场温室气体排放的重点环节,主要分为奶牛养殖活动温室气体排放以及牛场日常运行耗能两个方面;结合奶牛养殖肠道发酵和粪污管理的温室气体核算方法,归类整理了主要的减排措施,包括进行提高饲料质量和转化效率、粪污高效管理、清洁能源替代等方式,助力奶牛养殖实现低碳乃至零碳排放。  相似文献   

Comparison of emission estimates for non‐CO2 greenhouse gases from livestock and poultry in Korea from 1990 to 2010          下载免费PDF全文

Chunhyun Paik  Yongjoo Chung  Hugon Kim  Young Jin Kim 《Animal Science Journal》2016,87(4):612-623

It has often been claimed that non‐carbon dioxide greenhouse gases (NCGGs), such as methane, nitrous oxide and fluorinated greenhouse gases, are significant contributors to climate change. Here we nvestigate emission estimates of methane and nitrous oxide from livestock and poultry production, which is recognized as a major source of those NCGGs, in Korea over the period of 1990 through 2010. Based on the data on livestock and poultry populations, emission estimates of methane and nitrous oxide are first derived based on the Tier 1 approach. Then, the Tier 2 approach is adopted to obtain emission estimates of methane and nitrous oxide from cattle, which are known to be the largest sources of these NCGGs and account for about 70% of emissions from livestock and poultry in Korea. The result indicates that the Tier 2 estimates of methane and nitrous oxide emissions from enteric fermentation and manure management are significantly different from the Tier 1 estimates over the analysis period.  相似文献   

In vitro rumen fermentation and digestibility of buffaloes as influenced by grape pomace powder and urea treated rice straw supplementation          下载免费PDF全文

Suban Foiklang  Metha Wanapat  Thitima Norrapoke 《Animal Science Journal》2016,87(3):370-377

This study aimed to investigate the effect of grape pomace powder levels and roughage sources on gas kinetics, digestibility and fermentation of swamp buffaloes by using in vitro techniques. The experimental design was a 2 × 4 factorial arrangement in a completely randomized design. Factor A was two sources of roughage (untreated rice straw, RS, and 3% urea treated rice straw, UTRS) and factor B was four levels of grape pomace powder (GPP) supplementation (0, 2, 4, 6% of substrate) on a dry matter basis. Results revealed that GPP supplementation at 2, 4 and 6% of substrate influenced gas kinetics. Cumulative gas production tended to be lower in the supplemented group. In vitro true digestibility was higher in the GPP supplementation at 2% with UTRS while microbial mass was higher in the supplemented groups. Supplementation of GPP significantly increased the total volatile fatty acids, especially propionate. Calculated methane production was subsequently decreased in the supplemented groups. Bacterial population was higher while protozoal population was lower by GPP supplementation. It could be concluded that supplementation of GPP at 2% of the substrate with UTRS improved in vitro true digestibility, rumen fermentation end‐products as well as reducing methane production.  相似文献