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Emissions of the indirect greenhouse gases NH3 and NOx from Australian beef cattle feedlots 澳大利亚肉牛饲养场排放的间接温室气体NH3和NOx
Pub Date : 2008-01-21 DOI: 10.1071/EA07276
O. T. Denmead, Deli Chen, D. Griffith, Z. Loh, M. Bai, T. Naylor
Emissions of indirect greenhouse gases, notably the nitrogen gases ammonia (NH3) and the odd oxides of nitrogen (NOx), play important roles in the greenhouse story. Feedlots are intense, but poorly quantified, sources of atmospheric NH3 and although production of NOx is to be expected in feedlots, rates of NOx emission are virtually unknown. In the atmosphere, these gases are involved in several transformations, but eventually return to the earth in gaseous or liquid form and can then undergo further transformations involving the formation and emission of the direct greenhouse gas nitrous oxide (N2O). The IPCC Phase II guidelines estimate that indirect N2O emissions due to atmospheric deposition of N compounds formed from NH3 and NOx could be ~14% of the direct emissions from agricultural soils or from animal production systems. IPCC recommends that these indirect emissions be accounted for in making inventory estimates of N2O emission. This paper is a preliminary report of emissions of NH3 and NOx from two Australian feedlots determined with micrometeorological techniques. Emissions of nitrogen gases from both feedlots were dominated by emissions of NH3. The average NH3 emission rate over both feedlots in winter was 46 g N/animal.day, while that of NOx was less than 1% of that rate at 0.36 g N/animal.day. It was apparent that NH3 release was governed by the wetness of the surface. Rates of emission from the feedlot with the wetter surface were almost three times those from the other. The IPCC default emission factor for the combined emission of NH3 and NOx from livestock is 0.2 kg N/kg N excreted, but in our work, the emission factor was 0.59 kg N/kg N excreted. Potential emissions of N2O due to NH3 and NOx deposition were estimated to be of the same magnitude as the direct N2O emissions, the sum of direct and potential indirect amounting to ~3 g N2O-N/animal.day. If applied nationally, this would represent a contribution of N2O from Australian feedlots of 533Gg CO2-e or 2.2% of all Australian N2O emissions.
间接温室气体的排放,特别是氮气体氨(NH3)和氮氧化物(NOx),在温室效应中起着重要作用。饲养场是大气NH3的密集来源,但缺乏量化,尽管预计饲养场会产生氮氧化物,但氮氧化物排放率实际上是未知的。在大气中,这些气体参与了几次转化,但最终以气态或液态形式返回地球,然后可以进行进一步的转化,包括形成和排放直接温室气体一氧化二氮(N2O)。IPCC第二阶段指南估计,由于NH3和NOx形成的N化合物在大气中的沉积而间接排放的N2O可能占农业土壤或动物生产系统直接排放的14%。政府间气候变化专门委员会建议,在编制一氧化二氮排放清单估算时,应考虑到这些间接排放。本文是用微气象技术测定澳大利亚两个饲养场NH3和NOx排放量的初步报告。两个饲养场的氮排放以NH3排放为主。两个饲料场冬季NH3平均排放量为46 g N/头。而在0.36 g N/动物d时,氮氧化物的生长量不足该比率的1%。很明显,NH3的释放受地表湿度的支配。表面较湿的饲养场的排放率几乎是另一个饲养场的三倍。IPCC对畜禽NH3和NOx联合排放的默认排放因子为0.2 kg N/kg N排泄,但在我们的工作中,排放因子为0.59 kg N/kg N排泄。NH3和NOx沉积导致的N2O潜在排放估计与直接N2O排放量相同,直接和潜在间接排放的总和约为~3 g N2O- n /动物日。如果在全国范围内应用,这将代表澳大利亚饲养场对N2O的贡献为533g CO2-e,占澳大利亚N2O总排放量的2.2%。
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引用次数: 43
Persistence of defaunation effects on digestion and methane production in ewes 腐烂对母羊消化和甲烷产生的持续影响
Pub Date : 2008-01-21 DOI: 10.1071/EA07298
S. H. Bird, R. Hegarty, R. Woodgate
The effect of defaunation on feed digestion and on methane production of ewes was determined 10 and 25 weeks after defaunation. When fed a lucerne diet (800 g/day), the absence of protozoa did not change the apparent digestibility of dry matter, excretion of macro-minerals, or methane production 10 or 25 weeks post-treatment. Defaunation did, however, increase microbial protein flow by 22% (estimated from allantoin excretion) and the molar proportions of acetate and butyrate in the rumen, while decreasing excretion of copper and manganese. The fermentation data contrasts with previous studies that found defaunation reduced methanogenesis and rumen acetate proportions, but supports the hypothesis that a reduction in rumen acetate percentage is required to achieve reduced methanogenesis through defaunation.
在腐烂10周和25周后测定腐烂对母羊饲料消化和产甲烷的影响。饲喂紫花苜蓿日粮(800 g/d)时,原生动物的缺失并未改变处理后10周或25周的干物质表观消化率、大量矿物质的排泄或甲烷产量。然而,去faunation确实使微生物蛋白流量增加了22%(根据尿囊素排泄量估算),并使瘤胃中乙酸和丁酸盐的摩尔比例增加,同时减少了铜和锰的排泄量。发酵数据与先前的研究结果相反,即腐臭降低了甲烷生成和瘤胃醋酸盐比例,但支持了通过腐臭减少甲烷生成需要降低瘤胃醋酸盐百分比的假设。
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引用次数: 49
Isolation of sulfide oxidisers for desulfurising biogas produced from anaerobic piggery wastewater treatment in Taiwan. 台湾养猪场厌氧废水沼气脱硫用硫化物氧化剂的分离。
Pub Date : 2008-01-21 DOI: 10.1071/EA07248
Jung-Jeng Su, Yen-Jung Chen, Yuanyuan Chang, Szu-Ching Tang
This study aimed to improve the utilisation of biogas in pig farms, the promotion of biogas use and the reduction of greenhouse gas (i.e. methane, carbon dioxide, and nitrous oxide) emissions to the atmosphere. Sulfur oxidisers can convert sulfide (S2–) to sulfur (S0) and even sulfate (SO42–). Strains of CYAS-1, CYAS-2, SW-1, SW-2, and SW-3 were isolated from environmental samples and proven to have capabilities of sulfide oxidation by growing them in 150 mL liquid media with 1.5 g sulfur powder. An increase in sulfate concentration was used to select sulfide oxidisers. Strains CYAS-1 and CYAS-2, which both had significant sulfide oxidation capability, were isolated from the sludge of piggery wastewater treatment facilities. Moreover, strains SW-1, SW-2, and SW-3 were isolated from a pilot-scale biogas bio-filter (BBF) reactor. The experimental results showed that strain CYAS-1 (identified as Acinetobacter spp.), grown in diluted trypticase soy broth (TSB) with sulfur powder, increased the concentrations of SO42– from 17.2 ± 0.5 to 23.8 ± 1.0 mg/L (38.4% increase). Strain CYAS-2 (identified as Corynebacterium spp.), grown in diluted TSB with sulfur powder, increased concentrations of SO42– from 17.7 ± 0.1 to 25.9 ± 0.9 mg/L (47.0% increase). Concentrations of SO42– were increased 40.5, 33.6, and 29.7% in the presence of strains SW-1 (Candida kruse/inconspicua; 96.2% identity), SW-2 (Candida parapsilosis; 93.2% identity), and SW-3 (Trichosporon mucoides; 95.7% identity), respectively.
本研究旨在提高养猪场沼气的利用率,促进沼气的使用,减少温室气体(即甲烷、二氧化碳和一氧化二氮)排放到大气中。硫氧化剂可以将硫化物(S2 -)转化为硫(S0),甚至硫酸盐(SO42 -)。从环境样品中分离出CYAS-1、CYAS-2、SW-1、SW-2和SW-3菌株,并在150 mL含1.5 g硫粉的液体培养基中培养,证明其具有硫化物氧化能力。硫化物氧化剂的选择采用增加硫酸盐浓度的方法。从养猪场污水处理设施的污泥中分离出具有较强硫化物氧化能力的菌株CYAS-1和CYAS-2。此外,菌株SW-1、SW-2和SW-3从沼气生物滤池(BBF)中试反应器中分离得到。结果表明,在添加了硫粉的胰酶豆汤(TSB)中培养CYAS-1菌株(鉴定为不动杆菌),可使SO42 -浓度从17.2±0.5 mg/L提高到23.8±1.0 mg/L(提高38.4%)。菌株CYAS-2(鉴定为棒状杆菌spp.)在含有硫粉的稀释TSB中生长,使SO42 -浓度从17.7±0.1 mg/L增加到25.9±0.9 mg/L(增加47.0%)。菌株SW-1的存在使SO42 -浓度分别升高了40.5%、33.6%和29.7%。96.2%的同一性),SW-2(假丝酵母菌;93.2%的同一性),SW-3(粘毛霉;95.7%认同)。
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引用次数: 6
Policy options to manage greenhouse gas emissions from the livestock sector: an Australian perspective 管理畜牧业温室气体排放的政策选择:澳大利亚的观点
Pub Date : 2008-01-21 DOI: 10.1071/EAV48N2POLICY
D. Ugalde, J. V. Vliet, Anthony McGregor, B. Slattery
The interface between policy and science provides rich opportunity to frame both the policy and science agendas for the reduction of emissions of greenhouse gases from agriculture. The current Greenhouse Gas in Animal Agriculture Conference (2007) provides a valuable forum for the development and integration of the two. Compared with the level of investments worldwide into technologies to reduce emissions from energy generation and transport, investments into managing and reducing emissions from the agriculture and land sectors have lagged, sadly, far behind. Nonetheless, there still remains strong opportunity to reduce substantially the net emissions from the land-based sector while also improving productivity and financial return (both short and long term). Over the past few decades, it has probably been the science agenda that provided the main impetus for understanding the management of processes that give rise to greenhouse gas emissions from agriculture and for improving management options to reduce these emissions. However, recently a range of new policy approaches (both in Australia and elsewhere) have come into play, and these approaches are now demanding a greater suite and possibly a different set of information from science – and over a short timeframe – to provide the technical means for change to be implemented. The challenge for science is to understand the new demands from the policy agendas, and to resolve how the science community can best deliver what is required. In this way science will be delivering additional benefits to agricultural industries and rural communities as activities in the land-based sector align with national interest and opportunities.
政策和科学之间的界面为制定减少农业温室气体排放的政策和科学议程提供了丰富的机会。当前的畜牧业温室气体会议(2007年)为两者的发展和整合提供了一个有价值的论坛。遗憾的是,与全世界对减少能源生产和运输排放的技术的投资水平相比,对管理和减少农业和土地部门排放的投资远远落后。尽管如此,仍然有很大的机会大幅减少陆地部门的净排放量,同时提高生产率和财务回报(短期和长期)。在过去的几十年里,可能是科学议程为理解农业产生温室气体排放的过程的管理以及改善管理方案以减少这些排放提供了主要动力。然而,最近一系列新的政策方法(在澳大利亚和其他地方)已经开始发挥作用,这些方法现在需要更多的、可能是不同的科学信息集——并且在短时间内——来提供实施变革的技术手段。科学面临的挑战是理解政策议程的新要求,并解决科学界如何才能最好地提供所需的东西。通过这种方式,随着陆上部门的活动与国家利益和机会保持一致,科学将为农业工业和农村社区带来额外的好处。
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引用次数: 3
Redirecting rumen fermentation to reduce methanogenesis 改变瘤胃发酵方向以减少甲烷生成
Pub Date : 2008-01-21 DOI: 10.1071/EA07218
T. McAllister, C. Newbold
McAllister, T. A., Newbold, C. J. (2008). Redirecting rumen fermentation to reduce methanogenesis.  Australian Journal of Experimental Agriculture, 48, (1-2), 7-13.
麦卡利斯特,t.a.,纽博尔德,c.j.(2008)。改变瘤胃发酵方向以减少甲烷生成。中国农业科学,2011,(1),344 - 344。
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引用次数: 438
Absence of persistent methane emission differences in three breeds of dairy cows 三种奶牛的甲烷排放不存在持续差异
Pub Date : 2008-01-21 DOI: 10.1071/EA07219
A. Münger, M. Kreuzer
In the present study, data from an experiment with 10 purebred Holstein, Simmental and Jersey cows each were analysed to test the assumption that there are genetically low methane-producing animals. Methane emission of cows offered forage ad libitum and some concentrate was measured for 3 days in open-circuit respiration chambers in weeks 8, 15, 23, 33 and 41 of lactation. Individual cow data were analysed in five different ways: (i) plotting the trend of methane per unit of dry matter intake (DMI) and milk yield over time; relating measured methane production to estimates derived from equations based on either; (ii) DMI or (iii) nutrient intake; (iv) relating residual feed intake (RFI) to methane emission; and (v) analysis of variance of cow × measurement interactions. The Holstein, Simmental and Jersey cows emitted on average 25, 25 and 26 g methane/kg DMI, respectively. There was no indication of individual cows with persistently low or high methane yield per kg DMI and per kg milk. Measured methane emissions differed from estimated values without a clear pattern, and the relationship between RFI and methane emission of the cows was weak. Finally, analysis of variance failed to show distinct patterns of methane per unit of DMI and milk for individual animals. The apparent lack of persistence of individual animal differences in methane yields suggests that genetic determination of this trait is of minor importance in dairy cows.
在目前的研究中,对10头纯种荷斯坦奶牛、西门塔尔奶牛和泽西奶牛的实验数据进行了分析,以验证存在基因上低甲烷排放动物的假设。于泌乳期第8、15、23、33和41周,在开式呼吸室中连续3 d测量奶牛自由饲喂饲料和部分精料的甲烷排放量。对奶牛个体数据进行了五种不同的分析:(i)绘制单位干物质摄入量(DMI)和产奶量随时间的变化趋势;将测量的甲烷产量与基于两者之一的方程得出的估计值联系起来;(ii) DMI或(iii)营养摄入量;(iv)将剩余采食量与甲烷排放联系起来;(v)奶牛与测量相互作用的方差分析。荷斯坦奶牛、西门塔尔奶牛和泽西奶牛的平均甲烷排放量分别为25、25和26 g /kg DMI。没有迹象表明个别奶牛的每公斤DMI和每公斤牛奶的甲烷产量持续低或高。实测甲烷排放量与估计值差异不明显,RFI与奶牛甲烷排放量的关系较弱。最后,方差分析未能显示出个体动物单位DMI和牛奶中甲烷含量的不同模式。甲烷产量的个体差异明显缺乏持久性,这表明这一性状的遗传决定对奶牛的重要性不大。
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引用次数: 56
GHG emissions during the storage of rough pig slurry and the fractions obtained by mechanical separation 生猪粗浆储存过程中的温室气体排放和机械分离得到的馏分
Pub Date : 2008-01-21 DOI: 10.1071/EA07239
E. Dinuccio, P. Balsari, W. Berg
Emissions of methane (CH4), carbon dioxide (CO2), nitrous oxide (N2O) and ammonia (NH3) during the storage of rough pig slurry and the fractions (solid and liquid) obtained by mechanical separation were investigated in a laboratory-scale study. Manures were stored for a period of 30 days in open vessels (1500 cm3 capacity) within a climate-controlled room which was kept at 25 ± 0.2°C. Gaseous emissions were determined with the dynamic chamber method by infrared photoacoustic detection. The main GHG emission from the liquid manures was CH4. CH4 losses from both liquid and solid fractions together were 3% higher than from the rough slurry. CO2 losses from both liquid and solid fractions together increased by 10% compared with rough pig slurry. Appreciable N2O fluxes were only measured from the solid fraction. Combining the losses during the storage of both liquid and solid fraction, they resulted in reduced NH3 emissions compared with the storage of the rough pig slurry. Evidence from the present study suggests that mechanical separation of pig slurry has the potential to increase up to 25% the emission of CO2-equivalents to the atmosphere during the storage of the separated fractions if compared with the rough slurry.
在实验室规模的研究中,研究了猪粗浆储存过程中甲烷(CH4)、二氧化碳(CO2)、氧化亚氮(N2O)和氨(NH3)的排放以及机械分离得到的固体和液体馏分。在温度为25±0.2°C的恒温室内,将粪便储存在1500 cm3容量的开放式容器中30天。采用红外光声检测的动态室法测定了气体发射。液肥排放的温室气体主要为CH4。液体和固体馏分的CH4损失量都比粗浆高3%。与粗浆相比,液体和固体馏分的CO2损失都增加了10%。可观的N2O通量仅从固体部分测量。结合液体和固体部分储存过程中的损失,与储存粗浆相比,它们减少了NH3的排放。来自本研究的证据表明,与粗浆相比,机械分离的猪浆有可能在分离馏分储存期间增加高达25%的二氧化碳当量排放到大气中。
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引用次数: 17
Nutritional management for enteric methane abatement: A review 肠道甲烷减排的营养管理:综述
Pub Date : 2008-01-21 DOI: 10.1071/EA07199
K. Beauchemin, M. Kreuzer, F. O'Mara, T. McAllister
A variety of nutritional management strategies that reduce enteric methane (CH4) production are discussed. Strategies such as increasing the level of grain in the diet, inclusion of lipids and supplementation with ionophores (>24 ppm) are most likely to be implemented by farmers because there is a high probability that they reduce CH4 emissions in addition to improving production efficiency. Improved pasture management, replacing grass silage with maize silage and using legumes hold some promise for CH4 mitigation but as yet their impact is not sufficiently documented. Several new strategies including dietary supplementation with saponins and tannins, selection of yeast cultures and use of fibre-digesting enzymes may mitigate CH4, but these still require extensive research. Most of the studies on reductions in CH4 from ruminants due to diet management are short-term and focussed only on changes in enteric emissions. Future research must examine long-term sustainability of reductions in CH4 production and impacts on the entire farm greenhouse gas budget.
各种营养管理策略,减少肠道甲烷(CH4)的生产进行了讨论。农民最有可能采取诸如增加饲粮中谷物含量、添加脂质和补充离子载体(> - 24ppm)等策略,因为这些策略除了提高生产效率外,还极有可能减少甲烷排放。改善牧场管理、用玉米青贮代替草青贮和使用豆类对减少甲烷有一定的希望,但其影响尚未得到充分的记录。一些新的策略,包括膳食中添加皂苷和单宁,选择酵母培养物和使用纤维消化酶,可能会减轻CH4,但这些仍需要广泛的研究。大多数关于饮食管理导致反刍动物甲烷减少的研究都是短期的,并且只关注肠道排放的变化。未来的研究必须考察甲烷产量减少的长期可持续性以及对整个农场温室气体预算的影响。
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引用次数: 1030
Supplementation with whole cottonseed reduces methane emissions and can profitably increase milk production of dairy cows offered a forage and cereal grain diet 补充全棉籽可减少甲烷排放,并可有效提高饲粮和谷物奶牛的产奶量
Pub Date : 2008-01-21 DOI: 10.1071/EA07224
C. Grainger, T. Clarke, K. Beauchemin, S. McGinn, R. Eckard
The experimental objective was to determine if whole cottonseed (WCS) could be used as a dietary supplement to reduce enteric methane emissions and profitably increase milk production from dairy cattle over the summer period when pasture is limited in quantity and has a low nutritive value. Fifty lactating cows, ~200 days in milk, were randomly allocated to one of two groups (control or WCS). Cows were offered lucerne hay (in the morning) and pasture silage (in the afternoon) made from a predominantly ryegrass sward in one group for 5 weeks. The hay and silage were placed on the ground in a bare paddock. Cows in each group were also individually offered cracked grain in a feed trough at 3 kg DM/cow.day at milking times. In addition, at milking times, cows in the WCS group were individually offered 2.7 kg DM/cow.day of untreated WCS with their grain supplement. Measurements of methane emissions (n = 12), using the SF6 tracer technique, were made in weeks 3 and 5 after the commencement of feeding treatments. Supplementation with WCS significantly reduced methane emissions by 12% (g/cow.day) and by 21% (g/cow.kg milk solids) and significantly increased yield of milk (n = 25) by 15%, milk fat by 19% and milk protein by 16%. WCS had no effect on concentration of milk fat or lactose, but resulted in a significant 3% decrease in protein concentration. WCS appears to be a promising supplement for reducing methane emissions and increasing milk production from dairy cattle when pasture is limited in quantity and has a low nutritive value.
本试验的目的是确定全棉籽(WCS)是否可以在牧草数量有限且营养价值较低的夏季期间作为饲粮补充剂,以减少肠道甲烷排放并有益地提高奶牛的产奶量。选取50头泌乳~200 d的奶牛,随机分为对照组和WCS组。一组奶牛饲喂紫花苜蓿干草(上午)和以黑麦草为主的草地青贮饲料(下午),连续5周。干草和青贮饲料放在光秃秃的围场的地上。每组奶牛分别饲喂3 kg DM/头的碎粒饲料。每天挤奶的时候。此外,在挤奶时,WCS组奶牛每头单独饲喂2.7 kg干物质。在未处理的WCS中添加谷物。使用SF6示踪技术测量甲烷排放量(n = 12),于饲喂处理开始后的第3周和第5周进行。添加WCS可显著降低12% (g/奶牛日)和21% (g/奶牛日)的甲烷排放量。牛奶产量(n = 25)显著提高15%,乳脂和乳蛋白分别提高19%和16%。WCS对乳脂和乳糖浓度没有影响,但导致蛋白质浓度显著降低3%。当牧场数量有限且营养价值低时,WCS似乎是减少甲烷排放和增加奶牛产奶量的有希望的补充。
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引用次数: 60
Reliability of the sulfur hexafluoride tracer technique for methane emission measurement from individual animals: an overview 六氟化硫示踪技术测量个体动物甲烷排放的可靠性:综述
Pub Date : 2008-01-21 DOI: 10.1071/EA07297
C. Pinares-Patiño, H. Clark
Measurements of enteric methane (CH4) emissions from individual animals have traditionally been made with indirect calorimetry techniques, which are both accurate and reliable. However, the expense and need for animal training and the extent to which calorimetric results can be extrapolated to free-ranging animals have been questioned and stimulated the development of the sulfur hexafluoride (SF6) tracer technique. The tracer technique is now widely used in New Zealand and many other countries for CH4 emission measurements on grazing and pen-fed cattle, sheep, deer and alpacas. Few studies with cattle and sheep have examined the validity of the SF6 tracer technique. Most of these studies have concluded that estimations of CH4 emission by this technique do not differ from those of calorimetric techniques, though some exceptions have been reported. There is general agreement that the tracer technique is associated with large between-animal variability in the CH4 emission estimates from animals on the same diet, but it remains unknown whether this is due to the environment, housing conditions or the technique itself. High within-animal variability has also been reported from tracer CH4 measurements. There is growing evidence that CH4 emission estimates by the tracer technique are positively influenced by the permeation rate (PR) of the SF6 gas from permeation tubes and it has been suggested that fate of the tracer in the rumen rather than unrepresentative breath sample collection is the likely reason for the latter. It is concluded that although some issues related to the tracer technique need to be clarified, using a narrow range in PR and balancing of PR between treatments should be practised in order to overcome the relationship between PR and CH4 emission estimates.
传统上,测量个体动物肠道甲烷(CH4)排放是用间接量热法技术进行的,这种技术既准确又可靠。然而,动物训练的费用和需要以及量热结果可以外推到自由放养动物的程度受到质疑,并刺激了六氟化硫(SF6)示踪技术的发展。示踪技术目前在新西兰和许多其他国家广泛用于放牧和圈养牛、羊、鹿和羊驼的CH4排放测量。很少有牛和羊的研究检验了SF6示踪技术的有效性。这些研究大多得出结论,这种技术对CH4排放的估计与量热法的估计没有区别,尽管有一些例外报道。人们普遍认为,示踪技术与相同饮食的动物的甲烷排放估计值在动物间存在较大差异有关,但尚不清楚这是由环境、饲养条件还是技术本身造成的。从示踪剂CH4测量中也报道了高动物内变异性。越来越多的证据表明,通过示踪技术估计的CH4排放量受到来自渗透管的SF6气体的渗透率(PR)的积极影响,并且有证据表明,示踪剂在瘤胃中的作用,而不是不具代表性的呼吸样本收集,可能是后者的原因。综上所述,尽管与示踪技术有关的一些问题需要澄清,但为了克服示踪技术与CH4排放估算之间的关系,应采用较窄的PR范围并平衡不同处理之间的PR。
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引用次数: 70
期刊
Australian Journal of Experimental Agriculture
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