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1.
Methane Production, Emission and Possible Control Measures in the Rice Agriculture 总被引：19，自引：0，他引：19
Wang Mingxing Shangguan Xingjian Shen Renxing Wassmann Reiner Seiler Wolfgang 《大气科学进展》1993,10(3):307-314
In the rice field methane is produced in the soil layer with depths of 2-25 cm. The vertical profile of methane production rate in the paddy soil during the water covering period differs from that in the paddy soil in dry phase. Only a small part, about 30%. of the produced methane is emitted to the atmosphere through rice plant, air bubbles, and molecular diffusion. Therefore, the methane emission rate from the rice field depends not only on the methane production rate in the soil, but also on the transport efficiency of the rice plant, air bubble formation that in turn depends on the production rate, and molecular diffusion.Field measurements show that methane emission rates from a particular rice field have very large diurnal, seasonal and interannual variations, which are related to soil characteristics, water regime, farming procedure, local climate, and rice growing activities. The relationship between the methane emission rate and the above mentioned factors is very complicated. The emission rate 相似文献
2.
Following the Balloon Intercomparison Campaigns carried out from the NSBF, Palestine, Texas, in the fall of 1982 (BIC1) and spring of 1983 (BIC2), three instruments have reported infrared measurements (one in emission and two in absorption) from which results on the concentration of methane between 20 and 40 km altitude have been deduced. While the absorption-retrieved concentration profiles are in excellent agreement, the results from the emission measurements are significantly lower. Recent methane profiles obtained by satellite and from Spacelab 1 are in satisfactory agreement with the absorption data reported here. 相似文献
3.
I. L. Kalyuzhnyi S. A. Lavrov A. I. Reshetnikov N. N. Paramonova V. I. Privalov 《Russian Meteorology and Hydrology》2009,34(1):35-45
Results of measuring methane emissions from the Lammin-Suo oligotrophic bog massif are considered. It is shown that emission intensity depends on the methane transport from the active layer of the peat bed. The highest emission intensity is observed in the sedge-sphagnum microlandscape and over swampy hollows of the hummock-ridge complex. It is found that the methane flux intensity approaches zero when the wetland level drops by 30–35 cm from the bog surface. Spatial methane emission variability is estimated within dominating bog landscapes. The methane emission reaches its maximum values (207%) in microlandscapes with oriented microrelief (hummock-ridge complex); in the central bog (sphagnum-suffrutescent-cottongrass landscape afforested with pine), it reaches its lowest level (76%). A model of methane emissions from bogs is developed. The model has been verified from the observational data. The comparison of model calculations with experimental data is indicative of their good agreement, which makes it possible to use the model in different calculations and assessments of the influence of natural factors on the methane emission intensity. 相似文献
4.
This assessment of the atmospheric methane budget for the African Continent is based on a set of experimental data obtained in tropical Africa including methane emission from various biogenic sources, and biomass burning, and methane consumption in savanna and forest soils. Emission rates from the various sources, uptake rates of soils, and complementary data from the litterature allow calculation of regional methane fluxes by means of different data bases. Biomass burning, animals and natural wetlands are the three dominant sources of methane in Africa while rice paddy fields and termites appear as minor sources. The total methane emission is estimated to be in the range 20–40 MT of CH4 per year, methane uptake by soils being less than 2 MT per year. Net methane emission from the African continent accounts for less than 10% of global emissions from terrestrial ecosystems. 相似文献
5.
V. A. Poddubny E. S. Nagovitsyna Yu. I. Markelov A. G. Buevich K. L. Antonov E. V. Omel&#;kova I. L. Manzhurov 《Russian Meteorology and Hydrology》2020,45(3):193-200
The problem of estimation of average fields of
air pollutant concentration based on local measurement data is stated:
the problem of the passive location of the atmosphere by wind, or the
problem of the fluid location of the atmosphere. The definitions of new
functions are given: the average effective field of concentration and
the average effective field of sources. The system of integral equations
these functions obey is also presented. The results of numerical
estimates of quasi-two-dimensional average fields of methane
concentration in the area of the Barents and Kara seas retrieved from
data on surface concentrations measured on Belyi Island in the summer of
2016 and 2017 are analyzed. A typical feature of the resulting fields is
their mosaic pattern, as well as the higher values of methane
concentration on the continent and in the coastal zone. 相似文献
6.
H. Wanner T. Künzle U. Neu B. Ihly G. Baumbach B. Steisslinger 《Meteorology and Atmospheric Physics》1993,51(1-2):117-138
Summary The Swiss Middleland is a 300×50 km large plain embedded between the Jura, whose highest elevations are between 1000 and 2000m MSL, and the Alps, whose highest peaks are about 400m MSL. Because this plain is the main residence area of Switzerland with a great variety of emission sources, it is also a location with high photosmog concentrations during the summer months.Within the framework of the Swiss POLLUMET (Air Pollution and Meteorology) programme, an initial summer smog field experiment was carried out during July 1990 with the participation of different research groups from Switzerland and Germany. The measurements showed that the ozone concentrations within the atmospheric boundary layer were remarkably variable. The highest concentrations in the upper mixed layer varied between 100 and 130 ppb. The background ozone concentration in the upper atmospheric boundary layer increased from day to day. However, a clear indication of long-range transport could not be found. Remarkable local and regional concentration differences are not only based on the complex structure of the large emission sources (highways, urban plumes). They are also the result of the interaction of convectively driven motion systems like slope and valley winds and mountain-plain circulation.With 14 Figures 相似文献
7.
我国华中地区稻田甲烷排放特征 总被引：12，自引：1，他引：12
本文主要讨论地处我国华中水稻生态区的湖南红壤稻田的CH4排放特征。稻田CH4排放的日变化都有一致的规律，即在下午16:00左右出现最大值；CH4排放的日变化幅度与天气条件和水稻植物体有关；CH4排放的日变化与温度日变化的相关性很好（R>0.90）。早稻和晚稻的CH4排放季节变化规律有明显的差别，这主要是由于早、晚稻水稻生长期间的天气特别是空气温度变化的差异引起的，早稻CH4排放率在水稻生长中期（6月）略大，而晚稻在水稻移栽后几天内CH4排放就达到整个季节中的最大值，以后随时间逐渐降低；缺水会使CH4排放率明显降低，而且在重新灌水后相当长时间内CH4排放率没有回升；CH4排放在全有机肥的田中最大，然后依次是常规施肥、全沼渣肥及化肥田；尿素、氯化钾和复合肥的多施可降低稻田CH4排放率；不同施肥田中CH4排放率的温度效应不同；施肥是控制CH4排放的一种可行手段；在整个晚稻生长季节中瞬时CH4排放率与瞬时温度呈明显的指数关系；在1991年双季水稻生长季节中，稻田中CH4的排放量为67.96 g·m-2，其中早稻的CH4排放率为0.36 g·m-2·d-1，晚稻为0.48 g·m-2·d-1。 相似文献
8.
Sulfur budget above the Eastern Mediterranean: relative contribution of anthropogenic and biogenic sources 总被引：1，自引：0，他引：1
G. KOUVARAKIS H. BARDOUKI N. MIHALOPOULOS 《Tellus. Series B, Chemical and physical meteorology》2002,54(3):201-212
To access the relative contribution of anthropogenic and biogenic sulfur sources to the sulfur budget in the Eastern Mediterranean, an area characterized by very high nss- levels, measurements of both wet and dry deposition of sulfur were performed at a remote area on the island of Crete (Finokalia) during a 3-yr period (1996–1999). The estimation of dry deposition is based on both gaseous sulfur dioxide (SO2 ) and particulate phase non-sea-salt sulfate (nss- ) and methane sulfonate (MSA) measurements. During the dry period, deposition of SO2 from long-range transport is the main component of anthropogenic sulfur deposition in the area. The results of the wet and dry deposition obtained at Finokalia have been compared with DMS emission from seawater obtained during two yearly surveys (1997–1998) in the Cretan Sea. Our results indicate that the contribution from biogenic sources to the sulfur budget in the Eastern Mediterranean, although negligible during winter, can account for up to 26% during summer. 相似文献
9.
采用静态箱-气相色谱法在江汉平原开展早稻、晚稻、中稻、虾稻和再生稻5种稻作类型温室气体排放监测试验,研究不同稻作模式下稻田CH4和N2O排放特征、总增温潜势及温室气体排放强度,为准确评估稻田生态系统温室气体排放提供参考依据。结果表明:CH4排放集中在水稻前期淹水阶段,排放峰值最高为虾稻（85.7 mg·m-2·h-1）,较其他稻作模式高71.7%~191.5%。N2O排放峰值主要出现于中期晒田和施肥阶段,排放峰值最高为再生稻（1100.7 μg·m-2·h-1）,较其他稻作模式高16.8%~654.9%。CH4累积排放量从大到小依次为虾稻、再生稻、早稻、晚稻、中稻;N2O累积排放量从大到小依次为再生稻、早稻、晚稻、中稻、虾稻;总增温潜势从大到小依次为虾稻、再生稻、早稻、晚稻、中稻;温室气体排放强度从大到小依次为虾稻、早稻、再生稻、晚稻、中稻。CH4排放占比为82.9%~99.0%,稻虾田高排放主要原因为持续淹水时间长、秸秆还田和饲料投入,探究该模式CH4减排举措最为关键;中稻由于水旱轮作,稻田温室气体排放最低,可作为低碳减排的主要稻作类型。 相似文献
10.
Ｍｏｄｅｌ ｆｏｒ Ｍｅｔｈａｎｅ Ｅｍｉｓｓｉｏｎ ｆｒｏｍ Ｒｉｃｅ Ｆｉｅｌｄｓ ａｎｄ Ｉｔｓ Ａｐｐｌｉｃａｔｉｏｎ ｉｎ Ｓｏｕｔｈｅｒｎ ＣｈｉｎａＤｉｎｇＡｉｊｕａｎｄＷａｎｇＭｉｎｇｘｉｎｇ（ＩｎｓｔｉｔｕｔｅｏｆＡｔｍｏｓｐｈｅｒ... 相似文献
11.
Tropospheric concentrations of methane in remote locations have averaged a yearly world-wide increase of 0.018±0.002 parts per million by volume (ppmv) during the period from January 1978 to December 1983. The concentrations in the north temperate zone are always greater than those in the south temperate zone by 7±1% because the major methane sources are all predominantly located in the northern hemisphere. The average world-wide tropospheric concentration of methane in dry air was 1.625 ppmv at the end of 1983, measured against an NBS standard certified as 0.97 ppmv (but with an accuracy of only ±1%). The world-wide concentration increases are described by a linear equation with a standard deviation of 0.003 ppmv for ten different collection periods during 1978–1983. The precision of measurement of the methane concentration in the atmospheric samples and in the standard was measured to be ±0.4% for each. Repetitive measurements of an air sample collected in November 1977 have shown the same concentration for six years with a standard deviation for these data of ±0.003 ppmv.The causes for the steady increase in methane concentration in the troposphere cannot be fixed with certainty from present data. Contributing causes can include increases in the source strengths from cattle and rice fields. The atmospheric concentrations of CO, CH4 and HO are all closely coupled with one another, and increased concentrations of CO and/or CH4 should cause reduced concentrations of HO, which in turn should lengthen the atmospheric lifetimes of CO and CH4.Among other physical and chemical effects, a increase of 0.18 ppmv per decade should contribute a greenhouse warming of about 0.04°C per decade. Other secondary contributions to the greenhouse effect from increases in CH4 may arise from methane-induced increases in stratospheric H2O, in tropospheric O3, and in numerous other trace species whose concentration is controlled by reaction with HO radicals.An increased CH4 source strength may result from the effect of increasing atmospheric temperatures on the known aqueous biological CH4 sources, such as swamps, and may be an added consequence of the greenhouse effect. 相似文献
12.
本文建立了一个区域尺度稻田生态系统CH4排放的初步模式，该模式能从理论上反映稻田CH4产生、传输与排放的机理，并提供了一种估计不同区域气候和土壤条件下稻田生态系统CH4排放总量的有效方法。模式主要包括三个部分:水稻的生长、土壤有机物的分解和CH4的产生、传输及排放过程。模式分别模拟了早稻和晚稻CH4的排放，模拟结果与实测比较接近，CH4的季平均排放量，模拟值与实测值的偏差在10% 左右。模式的敏感性实验表明，温度是稻田CH4排放规律的主要控制因子。 相似文献
13.
Joanne H. Shorter J. Barry Mcmanus Charles E. Kolb Eugene J. Allwine Brian K. Lamb Byard W. Mosher Robert C. Harriss Uwe Partchatka Horst Fischer Geoffrey W. Harris Paul J. Crutzen Hans-Josef Karbach 《Journal of Atmospheric Chemistry》1996,24(2):121-140
We have investigated methane emissions from urban sources in the former East Germany using innovative measurement techniques including a mobile real-time methane instrument and tracer release experiments. Anthropogenic and biogenic sources were studied with the emphasis on methane emissions from gas system sources, including urban distribution facilities and a production plant. Methane fluxes from pressure regulating stations ranged from 0.006 to 24. l/min. Emissions from diffuse sources in urban areas were also measured with concentration maps and whole city flux experiments. The area fluxes of the two towns studied were 0.37 and 1.9 g/m2/s. The emissions from individual gas system stations and total town emissions of this study are comparable to results of similar sites examined in the United States. 相似文献
14.
甲烷作为油气生产中的主要气态污染物和增温潜势较强的一类温室气体,其逃逸排放检测与核算是中国油气行业温室气体控制与减排过程中的首要问题。通过比较国内外油气行业逃逸甲烷排放核算方法,以及总结当前国内外油气田现场开展的甲烷排放检测研究,对油气行业企业级温室气体清单编制提出了建议。在甲烷逃逸排放核算方面,由于生产过程、工艺等出现的变化,建议加快建立符合我国油气生产实际情况的排放因子,纳入放空气燃烧的周期变化、绿色完井措施使用、陆上/海上油气生产等内容,鼓励油气生产企业通过设备组件统计、现场实测等方式进行排放因子更新。针对逃逸甲烷现场检测数据不足,影响核算结果对比的现状,在开展油气生产过程现场检测时,建议自下而上与自上而下检测方法相结合,保证检测结果的可验证性、可重复性,并谨慎看待针对部分油气生产区块的检测结果进行大尺度区域甲烷逃逸排放量的推算结果。 相似文献
15.
16.
A. G. Ryaboshapko P. A. Bryukhanov I. M. Bruskina 《Russian Meteorology and Hydrology》2010,35(6):394-400
Data on measuring chemical composition of the atmospheric precipitation sampled at the national network of monitoring transboundary
transport of pollutants over the period from the late 1970s to 2007 are generalized. The area of investigation covers northwestern
European Russia. It is shown that the errors of the principal pollutants (sulfur and nitrogen compounds) measurements are,
on average, within 6%. The precipitation character over the measurement period changed from subacid (4 < pH < 5) to neutral
(5 < pH < 6). The sulfur deposition intensity in the region decreases over the last decades on a permanent basis. An opposite
tendency is observed for the nitrogen deposition. Annually means both of sulfur and nitrogen depositions are close to the
critical loads adopted. The trajectory analysis of the air mass transport leading to a conclusion that main emission sources
of pollutants must be located in the Central European countries. It is supposed that the conditions of the 1999 Gothenburg
Protocol on abating acidifying substance emissions into the atmosphere are not observed, at least for nitrogen. 相似文献
17.
主要介绍了近 2 0年来稻田甲烷排放的模式研究和排放量的估算以及减少稻田甲烷排放的措施。数值模式是估算稻田甲烷排放量的一条有效途径 ,模式的研究现在正处于发展阶段。介绍了几个主要的模型 ,既有物理过程模型也有经验模型。年排放量的估算范围为 6 79～ 4 1 4Tg ,随着技术的发展和大量实验的进行估算值的精度正得到不断的提高。减排措施是减少稻田甲烷排放的必要手段 ,但是目前的减排技术均处于研究阶段 ,应用还不成熟 相似文献
18.
A. I. Obzhirov N. L. Pestrikova G. I. Mishukova V. F. Mishukov A. K. Okulov 《Russian Meteorology and Hydrology》2016,41(3):205-212
The spatial distribution of methane content and methane fluxes in the water in the north-western part of the Sea of Japan, in the Kuril basin of the Sea of Okhotsk, and in the near-Kuril part of the Pacific Ocean is studied using the data of marine research expeditions in 2005, 2010, and 2011. The studies revealed the significant variability of the methane flux depending on the source presence and on the sea surface conditions. The high emission of methane from water to the atmosphere is registered in the areas where its concentration exceeds the equilibrium values with the atmosphere. The use of the model of computation of the fields of currents and contaminant transport for the investigated water area enabled explaining the formation of the high concentration of methane in the center of vortices in the zones of sea water convergence in the water areas under study. 相似文献
19.
周边气象条件对南京城区大气污染物浓度的影响 总被引：4，自引：0，他引：4
针对2014年8月南京国际青年奥林匹克运动会期间周边地区污染源的减排控制研究,本文将2010-2012年8月的NCEP/NCAR 的6 h再分析资料作为驱动场,利用WRF模式处理得到时空尺度更为精细的风场资料,结合南京奥体中心观测点的颗粒物及气体污染物浓度资料,通过相关分析以及合成分析,诊断得到了8月影响南京地区主要污染物的周边源区及其关键输送通道。结果表明：尽管8月青奥会时段南京地区主导风为海洋吹向大陆的东南风,但影响南京地区主要污染物（SO2,NO2,PM10）浓度的外源及其主要输送路径各有不同。来自于南京西南部江西、湖南、湖北等地区的较远距离输送是对南京地区SO2浓度影响的关键通道;来自于南京正南方向（安徽、浙江一带）的近距离输送是对南京地区NO2浓度影响的关键通道;来自于南京西南部（湖北一带）的中远距离输送是对南京地区PM10浓度影响的关键通道。 相似文献
20.
R. A. Hill K. Smith K. Russell T. Misselbrook S. Brookman 《Journal of Atmospheric Chemistry》2008,59(2):83-98
Ammonia emissions from stored farm manures form a small but significant proportion (∼10%) of the total emitted annually from
UK sources. These emissions are regulated by factors including: the surface area of the store; the storage method; the physical
form of the stored manure and the source of manure. A method was developed to estimate in situ emissions from a range of store
types (weeping wall and earth-banked lagoon) that are currently under-represented in UK emissions estimates. Passive diffusion
samplers (Willems Badges) were used to determine vertical concentration profiles to a height of 4.5 m at a number of locations
around each slurry store. An atmospheric dispersion model was applied to estimate the contribution from emissions from other
on-farm ammonia sources to the measured data and also to determine the emission rates from the stored manure. A procedure
was applied whereby the emission rates from each source were allowed to vary and a numerical equation solver was applied to
backfit the modelled data set to the field measurements. Measurements were collected at four farms on a monthly basis throughout
the year, with each dataset being collected over 24 h. The uncertainties in the estimates of emissions from the slurry stores
during individual measurement periods typically ranged between 20–40% though higher uncertainties occurred when emission fluxes
from the stores were below 0.25 g NH3–N m−2 day−1 and were entrained in the wakes, and mixed with the emissions, of adjacent buildings. The average emission from the farms
was 0.6 g NH3–N m−2 day−1 which agrees with other recent data on ammonia emissions from crusted slurry stores and, though it is within the range of
data considered in the UK emissions inventory, suggests that emissions from weeping wall stores and earth-banked lagoons may
be currently overestimated in national predictions. 相似文献