We thank Anne Gibson, Katherine Jones, Chris Kolodziejczyk, Alicia Naranjo, Kyle Tiner, and numerous students and temporary technicians for operating the LYCOG facility, conducting sampling, and data processing. L.G.R. acknowledges USDA-NIFA (2010-65615-20632).

1.收集土壤石柱用作称重测渗计<ol><li> 1.5米，深8毫米厚的钢构建开放式钢箱1×1米的正方形。 </li><li>按开放式盒垂直插入土中，用液压机安装在螺旋锚钻3米深入到土壤中。 </li><li>挖掘使用反铲挖土机或类似设备的包裹整体。 </li><li>放置在与土壤接触的玻璃纤维燃烧芯的整体件的基座。穿过钢基灯芯入10升的储排空整料，然后焊接钢底座上的框的底部。 </li><li>通过施加一个非残留除草剂，如草甘膦杀死在整料现有植被。 </li></ol> 2.建立土壤石柱植物群落<ol><li>植物与每个七种高杆草八苗的巨石野草，杂类草，为每平方米56工厂总密度。 <ol><li&gt;植物下面的草:Bouteloua curtipendula（侧燕麦GRAMA）， 裂稃棒 （小白羊），Sorghastrum垂穗（Indiangrass），Tridens albescens（白tridens）。 </li><li>植物以下福布斯: 丹参Residhotel Azurea酒店 （投手圣人）， 加拿大一枝黄花 （加拿大一枝黄花）， 合欢草属illinoensis（伊利诺伊bundleflower，豆类）。 </li></ol></li><li>在拉丁方设计植物幼苗，再随机为每个巨石。 </li><li>水下面种植移植约2个月。我们的目标是初步建立过程中尽量减少水分胁迫。使用任何方便的方法，如手杖或花园喷水器。浇水的频率取决于当地天气和气候，环境降雨的特别的发生。 </li><li>在最初的移植建立阶段，维持在环境降雨的移植，只要有必要的，而室（科3）构成。卸下建立由手工除草过程中出现的巨石有害物种。 </li></ol> 3.室内设计<ol><li>构建两院各宽1.2米，1.5米高，长60米，分为十个5米长的部分。从尺寸5米×1.2米×1.6米深，埋到1.5米重钢建设部分。 <ol><li>在每个部分中安装四个巨石，每两个土壤类型，随机二阶巨石。安装每个巨石顶上4540千克能力的平衡。 </li><li>包括Bastsil巨石在偶数段的配对。 </li></ol></li><li>加入地上部分用1米长×1米宽×0.3米高钣金导管，以提供一个途径气流相邻部分。 <ol><li>供应冷却剂在10℃下从161.4千瓦致冷单元到每个管道内的冷却盘管。 </li><li>附上清晰的棚膜，如其他使用的植物（厚度0.006"/ 15mm）的，气候操控实验23。 </li><li>适合每盖一个拉链开口由瓣草案的支持，以允许访问的巨石进行采样。 </li><li>取下塑料盖在生长季节的结束。 </li></ol></li></ol> 4， 二氧化碳和空气温度测量;温度控制<ol><li>两个样品室的入口和出口C A通过位于在superambient和低于环境室的入口和出口过滤空气样品线每2分钟。这些数据告诉二氧化碳注入和风扇转速控制。 <ol><li>样品C A和水汽含量，并在每个5米段在20分钟的间隔的入口和出口测量空气温度（T A）中。 </li><li>测量根据制造商的协议，使用红外气体分析仪的所有空气样本二氧化碳和水蒸汽的含量是实时的。 </li><li>测量T A在入口，中点，一个每个部分具有屏蔽细导线热电偶D出口。 </li></ol></li><li>调节冷却剂通过冷却盘管在每节，以保持从部分一致的平均值（中间部分）T A到接近室温T A部的入口的流动。 </li><li>定位量子传感器具有的天空一览无遗，并根据制造商的协议测量光量子通量密度。光平是输入鼓风机控制算法。 </li></ol> 5. C A处理中的应用<ol><li>白天<ol><li>混合纯的二氧化碳（CO 2）与进入的环境空气，以500μl的L-1 C A，在superambient腿的入口导管使用质量流量控制器。见第4 C A测量细节。 </li><li>通过使用风机入口处的第1室和下游段的平流输送富氧空气。 </li><li>中号通过调节风机转速aintain的390微升L-1（环境空气）所需的出口C A。 <ol><li>增加风机转速，如果出口C A低于设定值。这允许对CO 2的植物吸收较少的时间，从而获得更高的C出口甲 。 </li><li>降低鼓风机转速，如果C出口A是高于设定点。 </li></ol></li><li>使用在低于室温室同样的方法，除了将环境空气和控制，以实现250微升L-1出口C A。 </li></ol></li><li>夜间<ol><li>反向空气流的方向。 </li><li>注入二氧化碳进入superambient室的日间出口端达到530微升L-C A和控制平流率保持640微升L-1在夜间出口（白天入口。 </li><li>将环境空气在〜390微升L-1 的 CO 2进入夜间入口子环境室及控制平流率（白天出口）维持530微升L-1在夜间退出。 </li></ol></li></ol> 6.降水输入<ol><li>应用平均生长季节降雨量为每个整体。 <ol><li>从通过滴灌系统国产水源供水给每个整体。安排灌溉事件及其用量近似的实验场所季节性降雨模式。确切的时间表取决于当地的气候。 </li></ol></li><li>控制应用时机与数据记录器和测量应用卷流量计。 </li></ol> 7取样<ol><li>在二氧化碳控制期间测量体积土壤含水量（VSWC）每周的垂直剖面，用中子衰减仪或其他合适的探头。 <ol><li>推荐配置文件的增量为20厘米深度的增量1米德第p，和1个50厘米增量低于1微米。 </li></ol></li><li>衡量整体地上净初级生产力（ANPP）通过收集所有站在地上生物量在生长季节的结束。 <ol><li>所有地上生物量每年除去，因此现存生物表示当前的主生产。 </li><li>排序按品种，干燥至恒重采样量，并权衡。 </li><li>使用个别品种的生物质来量化植物物种ANPP的贡献。 </li></ol></li></ol>

<ol>
	<li>. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Contribution+of+Working+Group+I+to+the+Fifth+Assessment+Report+of+the+Intergovernmental+Panel+on+Climate+Change.">Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change.</a> Climate Change 2013: The Physical Science Basis. , 1535 (2013).</li><li>Gerhart, L. M., Ward, J. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Plant+responses+to+low+CO2+of+the+past.">Plant responses to low CO2 of the past.</a> New Phytol. 188 (3), 674-695 (2010).</li><li>Kimball, B. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cost+comparisons+among+free-air+CO2+enrichment,+open-top+chamber,+and+sunlit+controlled-environment+chamber+methods+of+CO2+exposure.">Cost comparisons among free-air CO2 enrichment, open-top chamber, and sunlit controlled-environment chamber methods of CO2 exposure.</a> Crit. Rev. Plant Sci. 11 (2-3), 265-270 (1992).</li><li>Hendrey, G. R., Lewin, K. F., Nagy, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Free+Air+Carbon+Dioxide+Enrichment:+DevelopmentProgress,+Results.">Free Air Carbon Dioxide Enrichment: DevelopmentProgress, Results.</a> Vegetatio. 104/105 (1), 16-31 (1993).</li><li>Weng, E., Luo, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Soil+hydrological+properties+regulate+grassland+ecosystem+responses+to+multifactor+global+change:+A+modeling+analysis.">Soil hydrological properties regulate grassland ecosystem responses to multifactor global change: A modeling analysis.</a> J. Geophys. Res. 113 (G3), G03003 (2008).</li><li>Brady, N. C., Weil, R. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The Nature and Properties of Soils. , 960 (2002).</li><li>Jenkinson, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Studies+on+the+decomposition+of+plant+material+in+soil.+V.+The+effects+of+plant+cover+and+soil+type+opn+the+logg+of+carbon+from+14C+labelled+ryegrass+decomposing+under+field+conditions.">Studies on the decomposition of plant material in soil. V. The effects of plant cover and soil type opn the logg of carbon from 14C labelled ryegrass decomposing under field conditions.</a> J. Soil Sci. 28 (3), 424-434 (1977).</li><li>Hassink, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preservation+of+plant+residues+in+soils+differing+in+unsaturated+protective+capacity.">Preservation of plant residues in soils differing in unsaturated protective capacity.</a> Soil Sci. Soc. Am. J. 60 (2), 487-491 (1996).</li><li>Oades, J. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+retention+of+organic+matter+in+soils.">The retention of organic matter in soils.</a> Biogeochemistry. 5 (1), 35-70 (1988).</li><li>Knapp, A. K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Consequences+of+more+extreme+precipitation+regimes+for+terrestrial+ecosystems.">Consequences of more extreme precipitation regimes for terrestrial ecosystems.</a> BioScience. 58 (9), 811-821 (2008).</li><li>Ainsworth, E. A., Long, S. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=What+have+we+learned+from+15+years+of+free-air+CO2+enrichment+(FACE)?+A+meta-analytic+review+of+the+responses+of+photosynthesis,+canopy+properties+and+plant+production+to+rising+CO2.">What have we learned from 15 years of free-air CO2 enrichment (FACE)? A meta-analytic review of the responses of photosynthesis, canopy properties and plant production to rising CO2.</a> New Phytol. 165 (2), 351-372 (2005).</li><li>Rogers, A., Ainsworth, E. A., Kammann, C. F. A. C. E., Nosberger, J., Long, S. P., Norby, R. J., Stitt, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ch+24:+Value:+Perspectives+on+the+Future+of+Free-Air+CO2+Enrichment+Studies.">Ch 24: Value: Perspectives on the Future of Free-Air CO2 Enrichment Studies.</a> Managed Ecosystems and CO2: Case Studies, Processes, and Perspectives. Ecological Studies. 187, 431-449 (2006).</li><li>Mayeux, H. S., Johnson, H. B., Polley, H. W., Dumesnil, M. J., Spanel, G. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+controlled+environment+chamber+for+growing+plants+across+a+subambient+CO2+gradient.">A controlled environment chamber for growing plants across a subambient CO2 gradient.</a> Funct Ecol. 7 (1), 125-133 (1993).</li><li>Polley, H. W., Johnson, H. B., Mayeux, H. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Carbon+dioxide+and+water+fluxes+of+C3+annuals+and+C4+perennials+at+subambient+CO2+concentrations.">Carbon dioxide and water fluxes of C3 annuals and C4 perennials at subambient CO2 concentrations.</a> Funct Ecol. 6 (6), 693-703 (1992).</li><li>Polley, H. W., Johnson, H. B., Mayeux, H. S., Malone, S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Physiology+and+growth+of+wheat+across+a+subambient+carbon+dioxide+gradient.">Physiology and growth of wheat across a subambient carbon dioxide gradient.</a> Ann. Bot. 71 (4), 347-356 (1993).</li><li>Polley, H. W., Johnson, H. B., Marino, B. D., Mayeux, H. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Increase+in+C3+plant+water-use+efficiency+and+biomass+over+glacial+to+present+CO2+concentrations.">Increase in C3 plant water-use efficiency and biomass over glacial to present CO2 concentrations.</a> Nature. 361 (6407), 61-64 (1993).</li><li>Polley, H. W., Johnson, H. B., Mayeux, H. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Increasing+CO2:+comparative+responses+of+the+C4+grass+Schizachyrium.+and+grassland+invader+Prosopis.">Increasing CO2: comparative responses of the C4 grass Schizachyrium. and grassland invader Prosopis.</a> Ecology. 75 (4), 976-988 (1994).</li><li>Polley, H. W., Johnson, H. B., Mayeux, H. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nitrogen+and+water+requirements+of+C3+plants+grown+at+glacial+to+present+carbon+dioxide+concentrations.">Nitrogen and water requirements of C3 plants grown at glacial to present carbon dioxide concentrations.</a> Funct. Ecol. 9 (1), 86-96 (1995).</li><li>Polley, H. W., Johnson, H. B., Mayeux, H. S., Brown, D. A., White, J. W. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Leaf+and+plant+water+use+efficiency+of+C4+species+grown+at+glacial+to+elevated+CO2+concentrations.">Leaf and plant water use efficiency of C4 species grown at glacial to elevated CO2 concentrations.</a> Int. J. Plant Sci. 157 (2), 164-170 (2012).</li><li>Polley, H. W., Johnson, H. B., Derner, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Increasing+CO2+from+subambient+to+superambient+concentrations+alters+species+composition+and+increases+above-ground+biomass+in+a+C3/C4+grassland.">Increasing CO2 from subambient to superambient concentrations alters species composition and increases above-ground biomass in a C3/C4 grassland.</a> New Phytol. 160 (2), 319-327 (2003).</li><li>Johnson, H. B., Polley, H. W., Whitis, R. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Elongated+chambers+for+field+studies+across+atmospheric+CO2+gradients.">Elongated chambers for field studies across atmospheric CO2 gradients.</a> Funct. Ecol. 14 (3), 388-396 (2000).</li><li>Gill, R. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nonlinear+grassland+responses+to+past+and+future+atmospheric+CO2.">Nonlinear grassland responses to past and future atmospheric CO2.</a> Nature. 417 (6886), 279-282 (2002).</li><li>Fay, P. A., Carlisle, J. D., Knapp, A. K., Blair, J. M., Collins, S. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Productivity+responses+to+altered+rainfall+patterns+in+a+C4-dominated+grassland.">Productivity responses to altered rainfall patterns in a C4-dominated grassland.</a> Oecologia. 137 (2), 245-251 (2003).</li><li>Miglietta, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Spatial+and+temporal+performance+of+the+miniface+(free+air+CO2+enrichment)+system+on+bog+ecosystems+in+northern+and+central+Europe.">Spatial and temporal performance of the miniface (free air CO2 enrichment) system on bog ecosystems in northern and central Europe.</a> Environmental Monitoring and Assessment. 66 (2), 107-127 (2001).</li></ol>

The authors have nothing to disclose.

该LYCOG设施达到保持C A浓度对三种土壤类型建立实验草地群落250〜500微升L-1连续梯度其业务目标。 C中的一个变化是线性的规定范围。每个部分内的空气温度升高，却被段之间的冷却盘管在大部分路段复位。其结果是，保持一致的平均温度从段到段的操作目标是满足以上多数渐变。温度和C 控制在春季和初夏期间容易维护，当土壤含水量较高，植物处于最高的光合能力。 议定书中的关键步骤 鼓风机速度的控制是保持在规定的 CO 2梯度的最关键的方面。控制是基于一个组合的反馈和前馈技术来满足空气流的植被碳吸收。反馈技术调整基于测量的目标和出口CO 2浓度之间的差风扇速度。馈控制在预期光合速率的变化，迅速（5秒的响应时间）调节风扇的转速，基于与所述量子传感器测量变化光合有效辐射。前馈控制大大提高了通过单独反馈控制来实现控制。通过腔室中的最大风量为1米秒 -1，或约3.6公里小时 -1，这是对风的低端的量级加速这些植物在现场看到。因此，不同的风扇转速不会影响植物反应。 维持CO 2梯度的另一个重要方面是足够的光合能力的存在。该梯度越陡，群体光合能力再大quired动用CO 2浓度。物种或社区更多叶面积，更高的光合速率，或更长的室长度都增加可达到的CO 2的牵伸。还应注意采取整体件体积和深度被选择为提供一个现实的生根量为既定的植物群落。这里使用的物种具有1生根深度 - 1.5米，但是其他物质可以是浅或更深，和整料体积应作相应的调整。最终的关键方面是可靠供应和控制的冷却水，以每个部分之间的冷却盘管的流动，以便腔室的温度相匹配，以在外界环境温度外日变化和季节变化的重要性。 修改到技术 操作的第一年表明，草原植被是勉强能够充分的CO 2 </sub&gt;缩编。这是补救的共有20个巨石从休斯顿和奥斯汀土系，以柳枝单一作物， 柳枝稷选择转换。柳枝稷是一种高产的本地高草，并充分浇水整个生长季节，确保即使在炎热的夏季沿梯度足够Ç吸收能力。第一年也透露大于所述腔室，从而降低流速在下游腔室预期气动阻力，从而导致过热。此问题已得到纠正通过安装额外的下游风机，以提高流速。我们建议安装新的聚乙烯覆盖每个生长季节，以保持最大的透光率。 该技术的局限性 该系统提出了在研究问题该设施能够支持创造机遇和限制某些业务问题。刀豆渐变控制从盛夏通过生长季节的结束变得更加困难，因为夏季气温较高下土壤水分，增加植物水分胁迫，降低光合能力。这反过来又要求较慢的空气流量来实现需要的满足目标C A的浓度，从而进一步提高了温度的C A画下来。此动态说明了这种系统的用于与CO 2浓度干旱相互作用研究的能力有限。每5米部内温度的升高是由于实验的直线流设计不可避免的。每一个腔室中的长波能量累积，直到空气经过冷却盘管和进入下一个腔室。在段温度升高类似幅度的一些预期的一些气候变化情景下未来气温升高较高估计的。因此，在截面温度变化再版esents机会分析草原反应C A和气候变暖之间的相互作用。最后，腔室的尺寸限制了植被的约一米的最大高度，和整料区植被限制为草本植物较小基部的区域。使用树种，例如，研究木本侵占草原，将是不切实际的超越苗期。 意义与其他技术相比 LYCOG相当操作相比，如面部和场外交易技术更经济。 LYCOG使用大约3700大号每月的 CO 2，其大于在MiniFACE系统24中的 CO 2的使用，但比的 CO 2消耗脸部的要少得多的和OTC接近3,12。的维持实验来自主要费用温度控制，其花费大约$ 30,000一年，compara竹叶提取二氧化碳费用开顶腔C A富集的成本，但仍比二氧化碳牺牲自由空气二氧化碳富集系统3的要少得多的估计。经济优势来在除了支持研究的独特能力在低于二氧化碳和沿连续的 CO 2梯度。 当前和未来应用 目前的研究审查生态系统的响应比ANPP等，包括土壤二氧化碳外排，而蒸发量，这将扩大我们在草地碳和水的循环C A影响土壤的具体变化的理解。未来的研究可能性包括通过操作两个室作为superambient但保持一个室在一个较暖温度差相对于环境温度相结合和CO 2处理，例如。当前vegetat离子可以很容易地更换与其他物种或地区学习如何变化，社会结构的影响CO对生态系统功能 2的效果。其他重要生态大气成分，如甲烷或臭氧可以被添加到测试用CO 2相互作用。

大气中的二氧化碳浓度（C A）最近增加了近400微升L -1约270微升L-1之前的工业革命。 C A预计2100年1至少要达到550微升L-1。增加这个比率超过观察，在过去50万年的任何C A的变化。改变C A的前所未有的速度提出了生态系统的非线性或阈值响应增加C A的可能性。大多数生态系统规模的C A浓缩试验只适用两种处理中，丰富了C A和控制单级。这些实验已经极大地扩展了我们的C 的丰富的生态系统影响的认识。然而，这可以揭示非线性的生态系统的响应的存在，以增加C A的替代方法是，跨到一个连续范围低于环境的生态系统的研究superambient C A。低于环境C A是很难在现场维护，并且最经常被使用生长室2研究。 Superambient C A一直用生长箱，开顶式气室，并提供免费空气富集技术3，4研究。 C A富集操作通过含有多种土壤类型的景观。土属性可以强烈地影响生态系统的反应，C A富集。例如，土壤质地确定的水和养分的土壤剖面5的保留，其可用性植物6，和有机物7-9的数量和质量。土壤水分的有效性是生态系统的反应时在水中有限的系统，包括最草原10 A富集的关键调解人。近场C A浓缩试验通常都检查只有一种土壤类型，以及控制不断诉测试arying C A富集在几个土壤类型所缺乏的。如果C A丰富的生态系统过程的影响具有不同土壤类型，有足够的理由期待空间变化的生态系统响应C A富集和气候11,12随之而来的变化。 的蒸渗仪二氧化碳梯度（LYCOG）设施的目的是要解决的空间变化的生态系统中的至C A水平范围从〜250到500微升L -1的非线性和阈值响应的问题。 LYCOG创建C A对多年生草地植物群落上代表广泛的质地，N和C的含量，以及水文美国中原南部的部分草原的性质土壤中生长的规定的梯度。在设施中使用的特定的土壤系列是休斯敦黑粘土（32巨石），一个变性土（城投Haplustert）典型的低地;奥斯汀（32巨石），高碳氮内特，粉质粘土软土（Udorthentic Haplustol）典型的高地;和Bastsil（16巨石），冲积砂壤土淋溶土（城投Paleustalf）。 在LYCOG采用的工作原理是利用植物的光合能力耗尽C A从包裹空气的定向移动通过封闭室。治疗目标是保持在C A的恒定线性白天梯度从500到250微升L-1。要做到这一点，LYCOG由两个线性腔室，一个腔室superambient保持梯度从500至390（环境）的部分微升L-1 C A，和低于环境室保持的390到250微升L-1部梯度。这两个腔室并排放置，面向上的南北轴。当植物光合能力是足够的一年中部分中的C A梯度维持;通常四月下旬至十一月初。 该室含有调节C A梯度，控制空气温度（T A）接近环境值，并应用统一的降水量所有的土壤需要的传感器和仪器。土壤是从安装在仪表以确定水预算的所有组分水文隔离称量渗漏池附近黑土大草原收集完好整料。水的量和时间，即近似的降雨事件的季节性和期间的平均年降水量达事件的应用。因此，LYCOG能够评估低于环境来superambient C A和土壤类型对草地生态系统功能的长期影响，包括水和碳预算。 LYCOG是第三代的美国农业部ARS草地水土保持研究实验室进行的C A梯度实验。第一代是一个雏形低于环境来所建立的梯度法13的活力和提高了我们的植物叶级生理反应的认识，以低于室温的C A 14-20变化的环境梯度。第二代是概念的油田规模的应用程序，以常年的 C 4草原，与延伸至200〜550μLL -1 21梯度。该油田规模试验首次提供了证据表明，用C草地生产力增加了浓缩可能饱和电流环境浓度20附近，部分原因是因为氮的可用性可能会限制植物生产力superambient C A 22。 LYCOG扩展了第二代实验通过将不同的纹理，让强大的测试在C草地群落的响应土壤的互动效应的复制的土壤。

<table><tbody><tr><td>Dataloggers, multiplexers</td><td>Campell Scientific, Logan, UT, USA</td><td>CR-7, CR-10, CR-21X, SDM-A04, SDM-CD16AC, AM25T</td><td></td></tr><tr><td>Thermocouples: Copper-constantan</td><td>Omega Engineering, Inc., Stamford, CT, USA</td><td>TT-T-40-SLE, TT-T-24-SLE</td><td></td></tr><tr><td>Quantum sensor</td><td>Li-Cor Biosciences, Lincoln, NE, USA</td><td>LI-190SB</td><td></td></tr><tr><td>CO2/H2O analyzer</td><td>Li-Cor Biosciences, Lincoln, NE, USA</td><td>LI-7000</td><td></td></tr><tr><td>Lysimeter scales</td><td>Avery Weigh-Tronix, Houston, TX, USA</td><td>DSL-3636-10</td><td></td></tr><tr><td>Air sampling pump</td><td>Grace Air Components, Houston, TX, USA</td><td>VP 0660</td><td></td></tr><tr><td>Dew-point generator</td><td>Li-Cor Biosciences, Lincoln, NE, USA</td><td>LI-610</td><td></td></tr><tr><td>Cold water chiller</td><td>AEC Application Engineering, Wood Dale, IL, USA</td><td>CCOA-50</td><td></td></tr><tr><td>Chilled water flow control values</td><td>Belimo Air Controls, Danbury, CT, USA</td><td>LRB24-SR</td><td></td></tr><tr><td>Chilled-water cooling coils</td><td>Coil Company, Paoli, PA, USA</td><td>WC12-C14-329-SCA-R</td><td></td></tr><tr><td>Carbon dioxide refrigerated liquid</td><td>Temple Welding Supply, Temple, TX, USA</td><td>UN2187</td><td></td></tr><tr><td>Polyethylene film</td><td>AT Plastics, Toronto, ON, Canada</td><td>Dura-film Super Dura 4</td><td></td></tr><tr><td>Blower motor/controller</td><td>Dayton Electric, Lake Forest, IL, USA</td><td>2M168C/4Z829</td><td></td></tr><tr><td>Solenoids</td><td>Industrial Automation, Cornelius, NC, USA</td><td>U8256B046V-12/DC</td><td></td></tr><tr><td>Leachate collection pump</td><td>Gast Manufacturing, Benton Harbor, MI, USA</td><td>0523-V191Q-G588DX</td><td></td></tr></tbody></table>

a co2 concentration gradient facility for testing co2 enrichment and soil effects on grassland ecosystem function

继续增加大气中二氧化碳的浓度（C a）任务技术研究对陆地生态系统的影响。大多数实验检查只有两个或C 的浓度和单个土壤类型的几级，但如果C A可改变为从低于环境的梯度superambient多个土壤浓度，就可以辨别过去的生态系统的响应是否可以继续直线在未来，无论是应对可能会在景观各不相同。在蒸渗仪二氧化碳梯度基金申请250至500微升L-C A梯度含有粘土，粉质粘土和沙土渗漏池建立黑土草原植物群落。该梯度为光合作用植被温控室封闭在创建逐步消耗的二氧化碳从空气通过室流出定向。保持适当的空气流率，足够photosynthetic能力，温度控制是至关重要的克服系统的主要局限，这是下降的夏季光合速率和增加水的压力。该设施是一种经济的替代的C A富集的其他技术，成功地洞察生态系统响应的形状，以低于环境到superambient C A富集，并且可以适于对测试为二氧化碳与其他温室气体，例如甲烷或臭氧相互作用。

渐变的superambient和低于环境部分被保持在单独的腔室（ 图1）。但是，超过七年操作（2007 - 2013年）的，所述腔保持在C中的线性梯度的浓度为500〜250微升L-1（图2）与只有一小的不连续性在C A的富集腔室的出口之间（整体式40）和梯度的低于环境部的入口（巨石41）。 气温和水汽压赤字依然从部分同时在superambient和低于环境室部分，恒除了在superambient室的第10条和第19及子环境室，在那里气温平均为〜3℃，温度超过其他20部（ 图2）。然而，有可发音的5温度升高 - 7°C各部分中，和correspondiNG增加了蒸气压赤字。 平均超过了2007年至2013年种植季节，VSWC呈线性变化，沿着C对两三种土壤的梯度（ 图3）。 VSWC前20厘米土壤剖面的C A上的沙壤土增长了3.1％，每100微升L-1增加（Bastsil系列）土（R 2 = 0.34，P = 0.01），每100 1.7％ μLL -1 C A上的粘土（休斯顿系列）。然而，有在0-20 VSWC没有改变粉质粘土（奥斯汀系列）土（P = 0.13）。 工厂的生产效率也呈线性变化，与C A和C A的幅度土壤中的反应各不相同。巨石与黑土草原植物群落ANPP（ 图4A）有最小的响应上的粘土C A，59克的C A -2增加每100微升L-1增加（R 2 = 0.22，p值= 0.02）。 ANPP的响应C A富集是在粉质粘土中间，由76克增加-2每100微升大号二氧化碳 -1（R 2 = 0.22，P = 0.02），和最伟大的沙质壤土，在那里ANPP获得131克-2每100微升大号的 CO 2 -1（R 2 = 0.55，P &lt;0.001）。 ANPP的这些土特异性反应，以C A对应密切的梅西奇的 C 4高杆草土特异性应答，Sorghastrum穗披碱草 ，最丰富的草种试验植物群落。 S的 ​​地上生物量增加垂穗最强烈的增加C A上的沙壤土，获得超过200克-2每100微升L-1增加C A（R 2 = 0.40，P = 0.005）。与此相反，S。垂穗获得了只有100克-1每100微升L-1增加C A的粉质粘土（R 2 = 0.50，P &lt;0.0001），而S.垂穗轻微回应C A上的粘土（R 2 = 0.12，P = 0.07; 图4B）。 土壤特异性增加ANPP与C A的富集发生尽管降低生产率上的两个更适应土壤的旱生的 C 4月中草Bouteloua curtipendula（图4C）。B. curtipendula是第二个最丰富的物种在实验社区。在粉质粘土土壤，B。 curtipendula是在低于C A浓度占主导地位的是草，最强烈的下降用 C丰富的粉质粘土（C中的一个69克-2，每100微升L-1增加; R 2 = 0.36，P &lt;0.008），不太强的沙质壤土下降（44克-2 </sup&gt;，每100微升L-1增加C A; R 2 = 0.36，P = 0.008），并没有用C有所不同的粘土（P = 0.46）一个浓缩。 <img alt="图1" src="/files/ftp_upload/53151/53151fig1.jpg" /> 图1.安排室和土壤，含草原植被原状土巨石（图）成长，和三个土壤类型沿CO 2梯度分布示意图室的两个线性序列。地块编号1 -对380 80 - - 250微升L-1部40位于沿500 -渐变的380微升L-1部分和数字41。图文:菲利普·费伊。 <img alt="图2" src="/files/ftp_upload/53151/53151fig2.jpg" /> 图2.小气候沿C A </st荣&gt; 渐变。白天生长季节的二氧化碳（CO 2）浓度，空气温度，并为80巨石的丰富和低于环境室蒸汽压赤字。值是在每个部分的空气入口和出口测量，并从其它位置的线性插值估计。数据点表示方式为2007年至2013年的生长季节。误差棒为清楚起见省略;平均标准误差分别为3.5 二氧化碳 ，0.82的空气温度和0.18蒸汽压赤字。 <img alt="图3" src="/files/ftp_upload/53151/53151fig3.jpg" /> 上沿的 CO 2梯度每土壤类型图3.土壤水分生长期容积土壤水分含量（VSWC）适用于0 - 20厘米为每个土壤类型的土壤剖面，由位置沿CO 2浓度gradien作图吨。线性回归绘制了土壤VSWC的显著关系，CO 2浓度。数据点表示到2013年生长季节2007手段。误差棒为清楚起见省略;意思是在介于0.74至0.99的三种土壤标准误差。 <img alt="图4" src="/files/ftp_upload/53151/53151fig4.jpg" /> 沿CO 2梯度每种土壤类型图4.工厂的生产效率。 （A）平均地上净初级生产力（ANPP），目前年生物所有物种中的60块体与黑土草原植物群落的总和;和当年生物质（二）梅西奇的 C 4高草，Sorghastrum穗披碱草 ，和（C）的旱生的 C 4 midgrass Bouteloua curtipendula沿CO 2浓度梯度绘制按位置。线性回归绘制了土壤的ANPP或物种生物量显著的关系，以CO 2浓度。数据点表示到2013年生长季节2007手段。误差棒为清楚起见省略;在三种土壤平均标准误差从34.9范围到42.5的ANPP，21.8至34.4为S.穗披碱草 ，和7.4 - 24.8为B. curtipendula。

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A CO2 Concentration Gradient Facility for Testing CO2 Enrichment and Soil Effects on Grassland Ecosystem Function

在蒸渗仪二氧化碳梯度设备创建了一个250到500μLL -1线性二氧化碳梯度对粘土，粉质粘土和沙土巨石温控室的住房草地植物群落。该设施被用来确定过去和未来的二氧化碳水平如何影响草地碳循环。

一个外线<sub&gt; 2</sub&gt;浓度梯度用于测试CO<sub&gt; 2</sub&gt;浓度与土壤对草地生态系统功能的影响

Continuing increases in atmospheric carbon dioxide concentrations (CA) mandate techniques for examining impacts on terrestrial ecosystems. Most ...

a-co2-concentration-gradient-facility-for-testing-co2-enrichment-soil

Nanyang Technological University

Research

JoVE Journal

Environment

A CO2 Concentration Gradient Facility for Testing CO2 Enrichment and Soil Effects on Grassland Ecosystem Function

11.4K 次观看.  Grassland Soil and Water Research Laboratory. 在蒸渗仪二氧化碳梯度设备创建了一个250到500μLL -1线性二氧化碳梯度对粘土，粉质粘土和沙土巨石温控室的住房草地植物群落。该设施被用来确定过去和未来的二氧化碳水平如何影响草地碳循环。 

视频: A CO2 Concentration Gradient Facility for Testing CO2 Enrichment and Soil Effects on Grassland Ecosystem Function

High-throughput Fluorometric Measurement of Potential Soil Extracellular Enzyme Activities

Microbes in soils and other environments produce extracellular enzymes to depolymerize and hydrolyze organic macromolecules so that they can be assimilated for energy and nutrients. Measuring soil microbial enzyme activity is crucial in understanding soil ecosystem functional dynamics. The general concept of the fluorescence enzyme assay is that synthetic C-, N-, or P-rich substrates bound with a fluorescent dye are added to soil samples. When intact, the labeled substrates do not fluoresce. Enzyme activity is measured as the increase in fluorescence as the fluorescent dyes are cleaved from their substrates, which allows them to fluoresce. Enzyme measurements can be expressed in units of molarity or activity. To perform this assay, soil slurries are prepared by combining soil with a pH buffer. The pH buffer (typically a 50 mM sodium acetate or 50 mM Tris buffer), is chosen for the buffer&#39;s particular acid dissociation constant (pKa) to best match the soil sample pH. The soil slurries are inoculated with a nonlimiting amount of fluorescently labeled (i.e. C-, N-, or P-rich) substrate. Using soil slurries in the assay serves to minimize limitations on enzyme and substrate diffusion. Therefore, this assay controls for differences in substrate limitation, diffusion rates, and soil pH conditions; thus detecting potential enzyme activity rates as a function of the difference in enzyme concentrations (per sample).
Fluorescence enzyme assays are typically more sensitive than spectrophotometric (i.e. colorimetric) assays,&#160;but can suffer from interference caused by impurities and the instability of many fluorescent compounds when exposed to light; so caution is required when handling fluorescent substrates. Likewise, this method only assesses potential enzyme activities under laboratory conditions when substrates are not limiting. Caution should be used when interpreting the data representing cross-site comparisons with differing temperatures or soil types, as in situ soil type and temperature can influence enzyme kinetics.

To measure potential rates of soil extracellular enzyme activities, synthetic substrates that are bound to a fluorescent dye are added to soil samples. Enzyme activity is measured as the fluorescent dye is released from the substrate by an enzyme-catalyzed reaction, where higher fluorescence indicates more substrate degradation.

潜在土壤胞外酶活性的高通量荧光测量

Microbes in soils and other environments produce extracellular enzymes to depolymerize and hydrolyze organic macromolecules so that they can be ...

科研

环境科学

Design and Operation of a Continuous 13C and 15N Labeling Chamber for Uniform or Differential, Metabolic and Structural, Plant Isotope Labeling

Tracing rare stable isotopes from plant material through the ecosystem provides the most sensitive information about ecosystem processes; from CO2 fluxes and soil organic matter formation to small-scale stable-isotope biomarker probing. Coupling multiple stable isotopes such as 13C with 15N, 18O or&#160;2H has the potential to reveal even more information about complex stoichiometric relationships during biogeochemical transformations. Isotope labeled plant material has been used in various studies of litter decomposition and soil organic matter formation1-4. From these and other studies, however, it has become apparent that structural components of plant material behave differently than metabolic components (i.e. leachable low molecular weight compounds) in terms of microbial utilization and long-term carbon storage5-7. The ability to study structural and metabolic components separately provides a powerful new tool for advancing the forefront of ecosystem biogeochemical studies. Here we describe a method for producing 13C and 15N labeled plant material that is either uniformly labeled throughout the plant or differentially labeled in structural and metabolic plant components.
Here, we present the construction and operation of a continuous 13C and 15N labeling chamber that can be modified to meet various research needs. Uniformly labeled plant material is produced by continuous labeling from seedling to harvest, while differential labeling is achieved by removing the growing plants from the chamber weeks prior to harvest. Representative results from growing Andropogon gerardii Kaw demonstrate the system&#39;s ability to efficiently label plant material at the targeted levels. Through this method we have produced plant material with a 4.4 atom%13C and 6.7 atom%15N uniform plant label, or material that is differentially labeled by up to 1.29 atom%13C and 0.56 atom%15N in its metabolic and structural components (hot water extractable and hot water residual components, respectively). Challenges lie in maintaining proper temperature, humidity, CO2 concentration,&#160;and light levels in an airtight 13C-CO2 atmosphere for successful plant production. This chamber description represents a useful research tool to effectively produce uniformly or differentially multi-isotope labeled plant material for use in experiments on ecosystem biogeochemical cycling.

Design and Operation of a Continuous 13C and 15N Labeling Chamber for Uniform or Differential, Metabolic and Structural, Plant Isotope Labeling

This method explains how to build and operate a continuous 13C and 15N isotope labeling chamber for uniform or differential plant tissue labeling. Representative results from metabolic and structural labeling of Andropogon gerardii are discussed.

设计一个连续和操作<sup&gt; 13</sup&gt; C和<sup&gt; 15</sup&gt;Ñ贴标商会统一或差分，代谢和结构，植物同位素标记

Tracing rare stable isotopes from plant material through the ecosystem provides the most sensitive information about ecosystem processes; from CO2 fluxes ...

Measurement of Greenhouse Gas Flux from Agricultural Soils Using Static Chambers

Measurement of greenhouse gas (GHG) fluxes between the soil and the atmosphere, in both managed and unmanaged ecosystems, is critical to understanding the biogeochemical drivers of climate change and to the development and evaluation of GHG mitigation strategies based on modulation of landscape management practices. The static chamber-based method described here is based on trapping gases emitted from the soil surface within a chamber and collecting samples from the chamber headspace at regular intervals for analysis by gas chromatography. Change in gas concentration over time is used to calculate flux. This method can be utilized to measure landscape-based flux of carbon dioxide, nitrous oxide, and methane, and to estimate differences between treatments or explore system dynamics over seasons or years. Infrastructure requirements are modest, but a comprehensive experimental design is essential. This method is easily deployed in the field, conforms to established guidelines, and produces data suitable to large-scale GHG emissions studies.

This article showcases the static chamber-based method for measurement of greenhouse gas flux from soil systems. With relatively modest infrastructure investments, measurements may be obtained from multiple treatments/locations and over timeframes ranging from hours to years.

从农业土壤使用静态钱伯斯温室气体流量测量

Measurement of greenhouse gas (GHG) fluxes between the soil and the atmosphere, in both managed and unmanaged ecosystems, is critical to understanding the ...

Measuring Carbon-based Contaminant Mineralization Using Combined CO2 Flux and Radiocarbon Analyses

A method is described which uses the absence of radiocarbon in industrial chemicals and fuels made from petroleum feedstocks which frequently contaminate the environment. This radiocarbon signal &#8212; or rather the absence of signal &#8212; is evenly distributed throughout a contaminant source pool (unlike an added tracer) and is not impacted by biological, chemical or physical processes (e.g., the 14C radioactive decay rate is immutable). If the fossil-derived contaminant is fully degraded to CO2, a harmless end-product, that CO2 will contain no radiocarbon. CO2 derived from natural organic matter (NOM) degradation will reflect the NOM radiocarbon content (usually &#60;30,000 years old). Given a known radiocarbon content for NOM (a site background), a two end-member mixing model can be used to determine the CO2 derived from a fossil source in a given soil gas or groundwater sample. Coupling the percent CO2 derived from the contaminant with the CO2 respiration rate provides an estimate for the total amount of contaminant degraded per unit time. Finally, determining a zone of influence (ZOI) representing the volume from which site CO2 is collected allows determining the contaminant degradation per unit time and volume. Along with estimates for total contaminant mass, this can ultimately be used to calculate time-to-remediate or otherwise used by site managers for decision-making.

Measuring Carbon-based Contaminant Mineralization Using Combined CO2 Flux and Radiocarbon Analyses

A protocol is described wherein CO2 mineralized from organic contaminant (derived from petroleum feedstocks) biodegradation is trapped, quantified, and analyzed for 14C content. A model is developed to determine CO2 capture zone's spatial extent. Spatial and temporal measurements allow integrating contaminant mineralization rates for predicting remediation extent and time.

测量碳为基础的污染物矿化结合使用CO<sub&gt; 2</sub&gt;助焊剂和放射性碳分析

A method is described which uses the absence of radiocarbon in industrial chemicals and fuels made from petroleum feedstocks which frequently contaminate ...

Measurements of CO2 Fluxes at Non-Ideal Eddy Covariance Sites

This protocol is an example of utilizing the eddy covariance (EC) technique to investigate spatially and temporally averaged net CO2 fluxes (net ecosystem production, NEP), in non-typical ecosystems, on a currently reforested windthrow area in Poland. After a tornado event, a relatively narrow &#8220;corridor&#8221; was created within surviving forest stands, which complicates such kind of experiments. The application of other measuring techniques, such as the chamber method, is even more difficult under these circumstances, because especially at the beginning, fallen trees and in general great heterogeneity of the site provide a challenging platform to perform flux measurements and then to properly upscale obtained results. In comparison with standard EC measurements carried out in untouched forests, the case of windthrow areas requires special consideration when it comes to the site location and data analysis in order to ensure their representativeness. Therefore, here we present a protocol of real-time, continuous CO2 flux measurements at a dynamically changing, non-ideal EC site, which includes (1) site location and instrumentation setup, (2) flux computation, (3) rigorous data filtering and quality control, and (4) gap filling and net fluxes partitioning into CO2 respiration and absorption. The main advantage of the described methodology is that it provides a detailed description of the experimental setup and measurement performance from scratch, which can be applied to other spatially limited ecosystems. It can also be viewed as a list of recommendations on how to deal with unconventional site operation, providing a description for non-specialists. Obtained quality-checked, gap filled, half-hour values of net CO2, as well as absorption and respiration fluxes, can be finally aggregated into daily, monthly, seasonal or annual totals.

Measurements of CO2 Fluxes at Non-Ideal Eddy Covariance Sites

The presented protocol uses the eddy covariance method at non-typical locations, applicable to all types of short-canopy ecosystems with limited area, on a currently reforested windthrow site in Poland. Details of measuring site setup rules, flux calculations and quality control, and final result analysis, are described.

非理想涡流位点的 CO2通量测量

This protocol is an example of utilizing the eddy covariance (EC) technique to investigate spatially and temporally averaged net CO2 fluxes (net ecosystem ...

Coupling Carbon Capture from a Power Plant with Semi-automated Open Raceway Ponds for Microalgae Cultivation

In the United States, 35% of the total carbon dioxide (CO2) emissions come from the electrical power industry, of which 30% represent natural gas electricity generation. Microalgae can biofix CO2 10 to 15 times faster than plants and convert algal biomass to products of interest, such as biofuels. Thus, this study presents a protocol that demonstrates the potential synergies of microalgae cultivation with a natural gas power plant situated in the southwestern United States in a hot semi-arid climate. State-of-the-art technologies are used to enhance carbon capture and utilization via the green algal species Chlorella sorokiniana, which can be further processed into biofuel. We describe a protocol involving a semi-automated open raceway pond and discuss the results of its performance when it was tested at the Tucson Electric Power plant, in Tucson, Arizona. Flue gas was used as the main carbon source to control pH, and Chlorella sorokiniana was cultivated. An optimized medium was used to grow the algae. The amount of CO2 added to the system as a function of time was closely monitored. Additionally, other physicochemical factors affecting algal growth rate, biomass productivity, and carbon fixation were monitored, including optical density, dissolved oxygen (DO), electroconductivity (EC), and air and pond temperatures. The results indicate that a microalgae yield of up to 0.385 g/L ash-free dry weight is attainable, with a lipid content of 24%. Leveraging synergistic opportunities between CO2 emitters and algal farmers can provide the resources required to increase carbon capture while supporting the sustainable production of algal biofuels and bioproducts.

A protocol is described to utilize the carbon dioxide in natural gas power plant flue gas to cultivate microalgae in open raceway ponds. Flue gas injection is controlled with a pH sensor, and microalgae growth is monitored with real time measurements of optical density.

将发电厂的碳捕获与半自动开放式管道池相结合，用于微藻养殖

In the United States, 35% of the total carbon dioxide (CO2) emissions come from the electrical power industry, of which 30% represent natural gas ...

Monitoring Pedogenic Inorganic Carbon Accumulation Due to Weathering of Amended Silicate Minerals in Agricultural Soils.

The present study aims to demonstrate a systematic procedure for monitoring inorganic carbon induced by enhanced weathering of comminuted rocks in agricultural soils. To this end, the core soil samples taken at different depth (including 0-15 cm, 15-30 cm, and 30-60 cm profiles) are collected from an agriculture field, the topsoil of which has already been enriched with an alkaline earth metal silicate containing mineral (such as wollastonite). After transporting to the laboratory, the soil samples are air-dried and sieved. Then, the inorganic carbon content of the samples is determined by a volumetric method called calcimetry. The representative results presented herein showed five folded increments of inorganic carbon content in the soils amended with the Ca-silicate compared to control soils. This compositional change was accompanied by more than 1 unit of pH increase in the amended soils, implying high dissolution of the silicate. Mineralogical and morphological analyses, as well as elemental composition, further corroborate the increase in the inorganic carbon content of silicate-amended soils. The sampling and analysis methods presented in this study can be adopted by researchers and professionals looking to trace pedogenic inorganic carbon changes in soils and subsoils, including those amended with other suitable silicate rocks such as basalt and olivine. These methods can also be exploited as tools for verifying soil inorganic carbon sequestration by private and governmental entities to certify and award carbon credits.

The verification method described here is adaptable for monitoring pedogenic inorganic carbon sequestration in various agricultural soils amended with alkaline earth metal silicate-containing rocks, such as wollastonite, basalt, and olivine. This type of validation is essential for carbon credit programs, which can benefit farmers that sequester carbon in their fields.

监测农业土壤中经修正的硅酸盐矿物风化造成的致病性无机碳积累。

The present study aims to demonstrate a systematic procedure for monitoring inorganic carbon induced by enhanced weathering of comminuted rocks in ...

<meta charset="utf8"></head><body>模拟甲烷菌生态位 – 梯度注射器模型生态系统

Agarose-Based Model Ecosystem for Cultivating Methanotrophs in a Methane-Oxygen Counter Gradient

Aerobic methane-oxidizing bacteria, known as methanotrophs, serve important roles in biogeochemical cycling. Methanotrophs occupy a specific environmental niche within methane-oxygen counter gradients found in soils and sediments, which influences their behavior on an individual and community level. However, conventional methods to study the physiology of these greenhouse gas-mitigating microorganisms often use homogeneous planktonic cultures, which do not accurately represent the spatial and chemical gradients found in the environment. This hinders scientists' understanding of how these bacteria behave in situ. Here, a simple, inexpensive model ecosystem called the gradient syringe is described, which uses semi-solid agarose to recreate the steep methane-oxygen counter gradients characteristic of methanotrophs' natural habitats. The gradient syringe allows for the cultivation of methanotrophic strains and the enrichment of mixed methane-oxidizing consortia from environmental samples, revealing phenotypes only visible in this spatially resolved context. This protocol also reports various biochemical assays that have been modified to be compatible with the semi-solid agarose matrix, which may be valuable to researchers culturing microorganisms within other agarose-based systems.

<meta charset="utf8"></head><body>作者聚焦:设计简单且廉价的技术在实验室中培养甲烷氧化细菌

A protocol is described for preparing a simple model ecosystem that recreates the methane-oxygen counter gradient found in the natural habitat of aerobic methane-oxidizing bacteria, enabling the study of their physiology in a spatially resolved context. Modifications to common biochemical assays for use with the agarose-based model ecosystem are also described.

基于琼脂糖的模型生态系统，用于在甲烷-氧反梯度中培养嗜甲烷菌

Aerobic methane-oxidizing bacteria, known as methanotrophs, serve important roles in biogeochemical cycling. Methanotrophs occupy a specific environmental ...

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潜在土壤胞外酶活性的高通量荧光测量

设计一个连续和操作

从农业土壤使用静态钱伯斯温室气体流量测量

测量碳为基础的污染物矿化结合使用CO

非理想涡流位点的 CO₂通量测量

将发电厂的碳捕获与半自动开放式管道池相结合，用于微藻养殖

监测农业土壤中经修正的硅酸盐矿物风化造成的致病性无机碳积累。

基于琼脂糖的模型生态系统，用于在甲烷-氧反梯度中培养嗜甲烷菌

基于琼脂糖的模型生态系统，用于在甲烷-氧反梯度中培养嗜甲烷菌

基于琼脂糖的模型生态系统，用于在甲烷-氧反梯度中培养嗜甲烷菌