Methane emissions during storage of di erent treatments from cattle manure in Tianjin

Many studies on methane emissions from animal manure have revealed that animal manure is a major source of methane emissions to the atmosphere that can have negative consequences for people, animals and environment. In general, the release of methane can be influenced by the type of feed taken by animals, temperature, manure characteristics and so on. This study aimed at quantifying and comparing methane release from dairy manure with di erent piling treatments. Four treatments were designed including manure piling height 30, 45, 60 cm and adding 6 cm manure every day until the piling height was 60 cm. Static chamber method and gas chromatography were adopted to measure the methane emissions from April to June in 2009. Methane emission rates of all four manure treatments were low in the first week and then increased sharply until reaching the peak values. Subsequently, all the methane emission rates decreased and fluctuated within the steady range till the end of the experiment. Wilcoxon nonparametric tests analysis indicated that methane emission rate was greatly influenced by manure piling height and manner. There were no significant relationships between methane emission rates and the temperatures of ambience and heap. However, regression analysis showed that the quadratic equations were found between emission rates of all treatments and the gas temperature in the barrels.     

Understanding gaseous reduction in swine manure resulting from nanoparticle treatments under anaerobic storage conditions

Manure is an impending source of carbon(C), sulfur(S) and water(H_2 O). Consequently,microbial populations utilize these constituents to produce methane(CH4), carbon dioxide(CO_2), greenhouse gases(GHGs), and hydrogen sulfide(H_2 S). Application of nanoparticles(NPs) to stored manure is an emerging GHG mitigation technique. In this study, two NPs: nano zinc oxide(nZnO) and nano silver(nAg) were tested in swine manure stored under anaerobic conditions to determine their effectiveness in mitigating gaseous emissions and total gas production. The biological sources of gas production, i.e., microbial populations were characterized via Quantitative Polymerase Chain Reaction(qPCR) analysis. Additionally, pH, redox, and VFAs were determined using standard methods. Each treatment of the experiment was replicated three times and NPs were applied at a dose of 3 g/L of manure. Also, headspace gas from all treatment replicates were analyzed for CH_4 and CO_2 gas concentrations using an SRI-8610 Gas Chromatograph and H_2 S concentrations were measured using a Jerome 631 X meter. Nanoparticles tested in this study reduced the cumulative gas volume by 16%–79% compared to the control. Among the NPs tested, only nZnO consistently reduced GHG concentrations by 37%–97%. Reductions in H_2 S concentrations ranged from 87% to97%. Gaseous reductions were likely due to decreases in the activity and numbers of specific gas producing methanogenic archaea and sulfate reducing bacterial(SRB)species.     

黄土及其他添加物对猪粪贮存过程氨气和温室气体排放的影响

畜禽粪肥在贮存阶段养分损失严重,是CO_2、CH_4、NH_3和N_2O等大气污染物的重要排放来源.本文采用室内培养方法,研究了添加黄土、秸秆、生物炭和膨润土对猪粪贮存过程中氨气及温室气体排放的影响.结果表明,添加10%用量的生物炭和膨润土处理的CO_2累积排放量与不添加任何添加物的猪粪对照相比分别降低了15.4%和20.9%,N_2O累积排放量分别降低了19.8%和37.6%.添加膨润土处理的NH_3损失量显著增加,但添加生物炭和膨润土处理的综合温室效应与猪粪对照相比均显著降低.添加10%秸秆处理的CH_4和NH_3累积排放量分别较猪粪对照降低了56.8%和95.8%,但其综合温室效应与对照相比差异不显著.模拟黄土垫圈过程添加黄土处理的氨气及温室气体累积排放量均显著降低,综合温室效应显著低于其他处理(p0.05).可见,黄土垫圈是保蓄粪肥碳、氮养分的有效措施,猪粪贮存阶段添加少量生物炭、膨润土对于减少粪肥综合温室效应具有积极作用.     

中国油气系统甲烷逸散排放估算

为实现碳达峰碳中和目标,中国正致力于推动能源低碳化转型,这促进能源由煤炭向油气资源的转变.因此,中国石油和天然气系统（油气系统）的甲烷（CH₄）排放日益受到关注.逸散排放包括设备泄漏、排空和火炬燃烧,涉及油气资源的开发、生产、运输、储存和分配等过程.但目前油气系统CH₄逸散排放缺乏统一的核算方法,逸散排放量亦未被纳入国家温室气体清单统计之中.基于相关方法,评估了1980~2020年中国油气系统的CH₄逸散排放.结果表明,油气系统的CH₄逸散排放随着油气资源的生产和消费增长而快速增加,由1980年不足60万t增长至2020年的超过260万t.石油系统和天然气系统在2020年的CH₄逸散排放分别达到约60万t和200万t,是1980年的1.38倍和16.6倍.油气系统的CH₄逸散主要源于天然气生产、石油生产、天然气分配、天然气运输和储存,分别占总排放的41%、20%、18%和13%.天然气管道是主要的逸散设施.相比于常规油气资源开发,非常规油气资源开发的排放强度更高.研究完善了CH₄逸散排放清单,可为CH₄减排提供重要科学数据支持.     

N2O emissions from agricultural soils in the North China Plain:the effect of chemical nitrogen fertilizer and organic manure

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添加剂对牛粪堆肥不同阶段真菌群落演替的影响

为研究物理添加剂对牛粪堆肥过程中真菌群落结构的影响,以牛粪和小麦秸秆为原料,以生物炭、火山石作为添加剂,进行了为期30d的堆肥实验.结果表明,好氧发酵基本实现牛粪无害化和稳定化的要求.高通量测序结果显示,堆肥原料中Wallemia占主导地位,相对丰度达到86.85%;堆肥高温阶段,空白处理和火山石处理中Wallemia、Aspergillus为优势菌属,而生物炭处理中Scedosporium、Acremonium相对丰度较高;降温阶段,Mycothermus和Thermomyces占优势,添加生物炭的处理中Thermomyces的相对丰度较其他两个处理高.腐熟阶段,3个处理中Mycothermus的相对丰度均为最高,而火山石的添加增加了Remersonia及Trichosporon的相对丰度.Spearman相关性分析结果表明,牛粪堆肥过程中Mycothermus与GI、TN、TP、NH₄⁺-N、含水率、pH值、VS、脲酶显著相关（P<0.05）.本研究从真菌变化的角度,为牛粪好氧发酵机理研究与工艺优化提供参考.     

内蒙古河套灌区盐碱土壤N2O排放特征

选择内蒙古河套灌区强度盐碱土壤S₁[电导率（EC）2.60dS/m]和轻度盐碱土壤S₂[电导率（EC） 0.74dS/m]为研究对象,2014~2016年,利用静态箱法3年野外原位观测试验,研究盐碱土壤氧化亚氮（N₂O）排放通量.结果表明：2种不同盐碱程度土壤N₂O排放每年均存在显著差异,轻度盐碱土壤N₂O累积排放量低;随EC升高,土壤盐碱程度加重,土壤N₂O累积排放量升高.2014~2016年作物生长季（4~11月）轻度盐碱土壤N₂O累积排放量分别为180.6,167.6,118.2mg/m²;强度盐碱土壤N₂O累积排放量比轻度盐碱土壤分别增加19%、26%和45%,修复盐碱土壤成为减缓盐碱土壤N₂O累积排放的重要农艺措施.     

Methane,nitrous oxide and ammonia emissions during storage and after application of dairy cattle slurry and influence of slurry treatment

Slurries are a significant source of CH₄, NH₃ and N₂O emissions to the atmosphere. The research project aimed at quantifying CH₄, NH₃ and N₂O emissions from liquid manure stores and after manure application under field conditions. The influence of the manure treatment options “no treatment”, “slurry separation”, “anaerobic digestion”, “slurry aeration” and “straw cover” on the emission level was investigated. Approximately 10 m³ of differently treated slurry were stored in pilot scale slurry tanks. Emissions were followed for c. 80 days. After the storage period, slurries were applied to permanent grassland. Greenhouse gas emissions from slurry were mainly caused by methane emissions during storage and by nitrous oxide emissions after field application of manures. Mitigation of GHG emissions can be achieved by a reduction in slurry dry matter and easily degradable organic matter content. Ammonia emissions mainly occurred after field application. Untreated slurry emitted 226.8 g NH₃ m⁻³ and 92.4 kg CO₂ eq. m⁻³ (storage and field application). Slurry separation (liquid fraction and composting of the solid fraction) resulted in NH₃ losses of 402.9 g m⁻³ and GHG losses of 58.5 kg CO₂ eq. m⁻³. Anaerobic digestion was a very effective means to reduce GHG emissions. 37.9 kg CO₂ eq. m⁻³ were lost. NH₃ emissions were similar to those from untreated slurry. Covering the slurry store with a layer of chopped straw instead of a wooden cover increased NH₃ emissions to 320.4 g m⁻³ and GHG emissions to 119.7 kg CO₂ eq. m⁻³. Slurry aeration nearly doubled NH₃ emissions compared to untreated slurry. GHG emissions were reduced to 53.3 kg CO₂ eq. m⁻³.     

2009~2019年中国人为CH4排放量的估算及时空格局

以中国340个地级及以上城市为研究对象,采用自下而上的核算方法,针对农业活动、能源活动和废物处理3个一级CH₄排放源,核算2009年和2019年中国人为CH₄排放量并分析其时空格局.结果表明：2009年中国人为CH₄总排放40.71Tg,2019年为42.89Tg,CH₄排放总量在增加,排放强度和人均排放量基本保持不变.一级排放源中,农业活动、能源活动和废物处理在2009年的CH₄排放量分别为24.88Tg、12.06Tg和3.76Tg,农业活动为主要排放源,2019年三者排放量分别为16.99Tg、21.62Tg和4.28Tg,能源活动成为主要排放源;二级排放源中煤炭开采的CH₄排放最多;不同城市中各排放源的占比存在较大差异,淮安、扬州和南通农业活动排放最多,晋城、大同和太原能源活动排放最多,而北京、上海和广州以废物处理排放为主.城市人为CH₄排放存在显著的空间正相关,高排放—高聚集的城市数量减少,分布集中;低排放—低聚集的城市数量增加,分布重心向东部地区转移;局部城市空间关联类型呈现出较强的空间锁定效应和迁移惰性特征.CH₄排放强度与人均CH₄排放的区域总体差异较大;CH₄排放强度地区间Theil指数差异较大,而地区内差异较小;人均CH₄排放地区间与地区内的Theil指数差异均较小.     

Mitigation Options for Enteric Methane Emissions from Dairy Animals: An Evaluation for Potential CDM Projects in India

Enteric fermentation in livestock is an important source of anthropogenic methane emission. India, with its large livestock population, is estimated to contribute 10.8 Tg of methane annually from this source. An evaluation of various methane mitigation options indicate that some of the available technologies like, diet supplementation with feed additive and molasses urea product are highly cost effective in reducing enteric methane emissions. The gross cost of methane abatement from use of feed additive monensin premix ranges from €0.6 to €1.8/ton CO₂ equivalent, for buffaloes and indigenous cows, respectively. The gross cost of enteric methane mitigation from supplementing molasses urea products and dietary manipulation through increased concentrate feeding is much higher. But, as the monetary value of the increased milk production on application of these technologies was higher than the annual cost of reduction strategy for buffaloes and crossbred cows, the net costs of the former mitigation option was negative for buffaloes (€-28.1/ton CO₂) and of the latter for crossbred cows (€-7.0/ton CO₂,). The availability of cost-effective technologies suggest that the methane mitigation projects under CDM, can be planned in the Indian dairy sector to the mutual benefit of countries with emission targets and India. The vast dairy animal population of India and resulting methane emissions provide good opportunity these countries to buy reasonable quantum of emission credits from projects in India. Such projects will work to the benefit to India by providing a tool for technology transfer to increase animal productivity and attract capital that assists in more prosperous and environmental friendly milk production in the country.     

花卉秸秆和牛粪联合堆肥的中试研究

以花卉废物和牛粪为原料 ,进行了温度反馈的通气量控制联合堆肥的中试研究 .一次发酵采用静态好氧床进行 ,过程控制采用温度反馈通气量控制方法 ,周期 2 0天 ;二次腐熟采用周期性翻堆 ,周期 4 0天 .试验分析了堆肥过程中堆体温度、水分、pH值、有机质、湿重、干重、体积、湿容重、干容重等指标随时间的变化特征 ,结果表明 :采用温度反馈通气量控制的静态好氧堆肥技术进行花卉废物和牛粪的联合堆肥可以有效控制堆肥过程 ,实现有机物料的快速稳定和去除水分 .     

Nanoparticles in mitigating gaseous emissions from liquid dairy manure stored under anaerobic condition

A number of mitigation techniques exist to reduce the emissions of pollutant gases and greenhouse gases(GHGs) from anaerobic storage of livestock manure. Nanoparticle(NP)application is a promising mitigating treatment option for pollutant gases, but limited research is available on the mode of NP application and their effectiveness in gaseous emission reduction. In this study, zinc silica nanogel(ZnSNL), copper silica nanogel(CuSNL), and N-acetyl cysteine(NACL) coated zinc oxide quantum dot(Qdot) NPs were compared to a control lacking NPs. All three NPs tested significantly reduced gas production and concentrations compared to non-treated manure. Overall, cumulative gas volumes were reduced by 92.73%–95.83%, and concentrations reduced by 48.98%–99.75% for H_2S, and 20.24%–99.82% for GHGs. Thus, application of NPs is a potential treatment option for mitigating pollutant and GHG emissions from anaerobically stored manure.     

基于漂浮箱法和扩散模型法测定淡水养殖鱼塘甲烷排放通量的比较

本研究以我国东南部地区淡水养殖鱼塘为研究对象,于2017年9月到2018年8月采用漂浮箱法和扩散模型法同步原位观测其CH_4排放通量,旨在明确运用两种不同方法观测CH_4的排放特征、排放强度及其驱动因子,综合比较两种方法观测结果的差异性,其中扩散模型法能够进一步量化扩散传输对CH_4排放通量的贡献.结果表明,两种方法观测的CH_4排放通量有相似的季节变化特征,即夏秋季排放高,冬春季排放低.通过漂浮箱法观测淡水养殖鱼塘CH_4排放通量的变化范围为0. 14～3. 13 mg·(m~2·h)~(-1),其年平均排放通量为(0. 86±0. 30) mg·(m~2·h)~(-1),而由扩散模型法估算出鱼塘CH_4排放通量变化范围为0. 04～1. 41 mg·(m~2·h)~(-1),其年平均排放通量为(0. 45±0. 08) mg·(m~2·h)~(-1).基于两种方法观测的CH_4排放通量具有相同的环境驱动因子,CH_4排放通量与水温、底泥可溶性有机碳(DOC)和水体化学需氧量(COD)呈现显著的正相关关系,与水体溶解氧(DO)呈现出极显著的负相关关系.综合比较两种方法观测结果,发现由扩散模型法估算出的淡水养殖鱼塘CH_4排放通量约为漂浮箱法测定结果的45%左右(P 0. 01),扩散模型法可能低估淡水养殖系统CH_4排放通量.综上所述,漂浮箱法更适合用于观测我国东南部内陆地区淡水养殖生态系统CH_4排放.     

长期定位有机物料还田对关中平原夏玉米-冬小麦轮作土壤NO排放的影响

农田土壤是大气光化学活性气体一氧化氮(NO)的主要人为源之一.为定量研究有机物料还田对NO排放的影响,利用静态暗箱法对关中平原26 a长期定位施肥夏玉米-冬小麦轮作农田NO排放通量进行周年(2016年6月至2017年6月)观测.除对照(CK)处理全年不施肥外,田间设3个施肥处理,冬小麦季分别为全化肥(NPK,165 kg·hm~(-2))、化肥加秸秆[NPKS,(165+40)kg·hm~(-2)]和化肥加牛粪[NPKM,(50+115)kg·hm~(-2)];夏玉米季均施等量化肥(188 kg·hm~(-2)).观测期内,CK处理NO排放通量较小[12.2 g·(hm~2·d)~(-1)];各施肥处理均在夏玉米播种、施肥和冬小麦施肥后出现排放峰,其中NPK处理峰值最高[112.0 g·(hm~2·d)~(-1)].各处理NO年排放总量和排放系数分别为0.13~0.57 kg·hm~(-2)和0.04%~0.12%.NPKS和NPKM处理年排放总量较NPK分别减少17.6%和增加68.0%(P0.05).与NPK处理相比,NPKS和NPKM冬小麦季排放总量降低41.1%~60.0%(P0.05);但夏玉米季增加25.2%~292.1%(P0.05).冬小麦季添加有机物料有效降低NO排放,而夏玉米季NO排放增加则与土壤有机质含量有关.     

天津市生活垃圾处理碳排放时间变化特征及影响因素

控制生活垃圾处理产生的温室气体已成为碳减排的重点方向之一。参考《省级温室气体清单编制指南（试行）》推荐方法核算了天津市2009—2018年生活垃圾处理碳排放量,分析碳排放时间变化特征,并采用改进Kaya恒等式和LMDI加和分解法的碳排放影响因素分解恒等式,分析天津市生活垃圾处理碳排放的影响因素。结果表明：2009—2018年天津市生活垃圾处理碳排放量呈现先降后增的趋势,碳排放量主要来自填埋处理;影响碳排放的因素中,经济产出效应（ΔY）对生活垃圾处理碳排放的驱动作用最大,碳排放强度效应（ΔCF）次之,生活垃圾排放强度效应（ΔWI）和生活垃圾处理结构强度（ΔWS）对碳排放具有负向作用。控制生活垃圾产生量、增加垃圾焚烧处理占比以及提高填埋场甲烷回收率是未来主要的减排方向。

     

零价铁与磁铁矿促进半干式猪粪厌氧产甲烷的效能与机理研究

本实验探究了相同剂量（5 g·L^-1）的零价铁、磁铁矿和两者的混合物对半干式猪粪厌氧消化过程的影响,重点揭示了零价铁和磁铁矿对甲烷生产的协同促进效能与机理.结果表明,与无添加剂的对照组相比,零价铁、磁铁矿和混合添加剂分别使系统的甲烷产量提高了32.8%、21.8%和35.1%.与单独添加零价铁或磁铁矿相比,混合添加剂对产甲烷的提升效果更佳.零价铁与磁铁矿对厌氧消化的协同促进效应体现在以下4个方面：①能更好地维持低氢气分压环境,推动产甲烷种间电子传递;②可使反应器的总碱度维持在相对较高的水平,提高系统缓冲 能力;③能增加厌氧体系中溶解性铁离子浓度,进一步提高厌氧微生物的活性;④同时富集能够介导种间氢传递和种间直接电子传递的细菌和古菌,提高有机底物转化为甲烷的效率.     

添加四环素和重金属锌对牛粪厌氧消化性能及四环素类抗性基因丰度的影响

为探究奶牛粪便中抗生素和重金属残留对厌氧消化和抗生素抗性基因的影响,本研究通过添加四环素(TC)、金属锌(Zn)与共同添加TC和Zn,分析了厌氧消化性能及四环素类抗性基因(tetC、tetG、tetO、tetT、tetW和tetX)和Ⅰ类整合酶基因(intI1)的变化.结果表明,添加TC或Zn会抑制厌氧消化产气,二者共...     

Methane emissions from rice fields under continuous straw return in the middle-lower reaches of the Yangtze River

A three-year experiment was conducted in the middle-lower reaches of the Yangtze River in China to study the influence of continuous wheat straw return during the rice season and continuous rice straw return in wheat on methane (CH 4 ) emissions from rice fields in which, the rice-wheat rotation system is the most dominant planting pattern. The field experiment was initiated in October 2009 and has continued since the wheat-growing season of that year. The analyses for the present study were conducted in the second (2011) and third (2012) rice growing seasons. Four treatments, namely, the continuous return of wheat straw and rice straw in every season (WR), of rice straw but no wheat straw return (R), of wheat straw but no rice straw return (W) and a control with no straw return (CK), were laid out in a randomized split-plot design. The total seasonal CH 4 emissions ranged from 107.4 to 491.7 kg/ha (2011) and 160.3 to 909.6 kg/ha (2012). The increase in CH 4 emissions for treatments WR and W were 289% and 230% in the second year and 185% and 225% in the third year, respectively, in relation to CK. We observed less methane emissions in the treatment R than in CK by 14%-43%, but not statistically significant. Treatment R could increase rice productivity while no more CH 4 emission occurs. The difference in the total CH 4 emissions mainly related to a difference in the methane flux rate during the first 30-35 days after transplant in the rice growing season, which was caused by the amount of dissolved oxygen in paddy water and the amount of reducible soil materials.     

2000~2020年京津冀BVOCs排放量估算及时空分布特征

为研究京津冀地区天然源挥发性有机化合物(BVOCs)近20a排放量及时空分布特征,本文基于卫星遥感解译获得的2000年、2005年、2010年、2015年、2020年共5期中国土地利用数据,计算获得了京津冀地区各市县BVOCs排放量及排放组成,同时对京津冀地区近20a的BVOCs排放的时空分布进行了特征分析.结果表明,近20a京津冀地区BVOCs平均排放总量为76.40万t/a,其中河北省、北京市、天津市的平均排放总量分别为59.11万t/a,15.29万t/a,2.00万t/a;按照排放组成分析,ISOP平均排放总量为16.80万t/a,占总排放量的21.99%,TMT平均排放总量为29.62万t/a,占总排放量的38.77%,OVOCs平均排放总量为29.97万t/a,占总排放量的39.23%.根据排放时间特征分析,京津冀地区冬季BVOCs排放量最低、夏季BVOCs排放量最高.BVOCs排放的空间分布与土地利用类型和植被分布密切相关,不同土地利用类型的BVOCs排放贡献具有显著差异,近20a京津冀地区林地、耕地、草地的BVOCs平均排放量分别为60.33万t/a,12.78万t/a,2.31万t/a,分别占总排放量的78.90%,16.79%,3.04%.京津冀地区BVOCs空间排放分布差异比较明显,北部、东北部的整体排放量明显高于南部、东南部.本研究可为BVOCs的计算提供研究思路,同时可为京津冀地区空气污染治理提供有关基础数据.     

不同温度下微生物和纤维素酶对发酵猪粪理化特性的影响

采用恒温发酵培养试验,研究了5℃和25℃时分别接种纤维素酶(X)、枯草芽孢杆菌(K)和EM菌(E)及其组合对新鲜猪粪发酵中的全氮、铵态氮、有机质、p H及微生物数量的影响.结果表明,5℃条件下,猪粪中微生物生长受抑制,细菌、真菌、放线菌数量均明显低于25℃,发酵终期猪粪有机质含量为70%~83%,p H值为7.16~7.36;25℃条件时,发酵终期猪粪有机质含量降至61%~72%,p H值升至8.09~8.94.与对照相比较,25℃下添加微生物和纤维素酶的处理有机质含量降低了2.95%~7.70%(除了K和XE处理),C/N值降低了4.04%~37.59%(除了XK处理),p H值增加了1.7%~26.8%.在总的添加量一致的条件下,发酵剂组合KE、XE、XK、XKE对猪粪发酵的效果优于单一发酵剂的X、K、E处理.