Design and Operation of a Continuous <sup>13</sup>C and <sup>15</sup>N 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 ...

Colorado State University

The aim of our study was to identify interactions between the decomposition of aboveground litter and rhizosphere activity. The experimental approach combined the placement of labelled litter (delta13C=-37.9 per thousand ) with forest girdling in a 35-year-old Norway spruce stand, resulting in four different treatment combinations: GL (girdled, litter), GNL (girdled, no litter), NGL (not girdled, litter), and NGNL (not girdled, no litter). Monthly sampling of soil CO2 efflux and delta13C of soil respired CO2 between May and October 2002 allowed the partitioning of the flux into that derived from the labelled litter, and that derived from native soil organic matter and roots. The effect of forest girdling on soil CO2 efflux was detectable from June (girdling took place in April), and resulted in GNL fluxes to be about 50% of NGNL fluxes by late August. The presence of litter resulted in significantly increased fluxes for the first 2 months of the experiment, with significantly greater litter derived fluxes from non-girdled plots and a significant interaction between girdling and litter treatments over the same period. For NGL collars, the additional efflux was found to originate only in part from litter decomposition, but also from the decay of native soil organic matter. In GL collars, this priming effect was not significant, indicating an active role of the rhizosphere in soil priming. The results therefore indicate mutual positive feedbacks between litter decomposition and rhizosphere activity. Soil biological analysis (microbial and fungal biomass) of the organic layers indicated greatest activity below NGL collars, and we suppose that this increase indicates the mechanism of mutual positive feedback between rhizosphere activity and litter decomposition. However, elimination of fresh C input from both above- and belowground (GNL) also resulted in greater fungal abundance than for the NGNL treatment, indicating likely changes in fungal community structure (i.e. a shift from symbiotic to saprotrophic species abundance).

Feedback interactions between needle litter decomposition and rhizosphere activity.

A new system for soil respiration measurement [P. Rochette, L.B. Flanagan, E.G. Gregorich. Separating soil respiration into plant and soil components using analyses of the natural abundance of carbon-13. Soil Sci. Soc. Am. J., 63, 1207-1213 (1999).] was modified in order to collect soil-derived CO2 for stable isotope analysis. The aim of this study was to assess the suitability of this modified soil respiration system to determine the isotopic composition (delta13C) of soil CO2 efflux and to measure, at the same time, the soil CO2 efflux rate, with the further advantage of collecting only one air sample. A comparison between different methods of air collection from the soil was carried out in a laboratory experiment. Our system, as well as the other dynamic chamber approach tested, appeared to sample the soil CO2, which is enriched with respect to the soil CO2 efflux, probably because of a mass dependent fractionation during diffusion and because of the atmospheric contribution in the upper soil layer. On the contrary, the static accumulation of CO2 into the chamber headspace allows sampling of delta13C-CO2 of soil CO2 efflux.

Sampling soil-derived CO2 for analysis of isotopic composition: a comparison of different techniques.

&#x6E29;&#x5E26;&#x548C;&#x5317;&#x65B9;&#x68EE;&#x6797;&#x751F;&#x6001;&#x7CFB;&#x7EDF;&#x5305;&#x542B;&#x5173;&#x4E8E;&#x571F;&#x5730;&#x3001; &#x751F;&#x7269;&#x91CF;&#x548C;&#x571F;&#x58E4;&#x6709;&#x673A;&#x8D28;&#x7684;&#x5F62;&#x5F0F;&#x50A8;&#x5B58;&#x7684;&#x78B3;&#x7684;&#x5F88;&#x5927;&#x4E00;&#x90E8;&#x5206;&#x3002;&#x589E;&#x52A0;&#x5927;&#x6C14; [CO2]&#x3001; &#x589E;&#x6E29;&#x3001; &#x9AD8;&#x7684;&#x6C2E;&#x6C89;&#x964D;&#x548C;&#x96C6;&#x7EA6;&#x5316;&#x7684;&#x7ECF;&#x8425;&#x5C06;&#x66F4;&#x6539;&#x6B64; C &#x5B58;&#x50A8;&#x3002;&#x5355;&#x56E0;&#x5B50;&#x53CD;&#x5E94;&#x7684;&#x51C0;&#x521D;&#x7EA7;&#x751F;&#x4EA7;&#x6709;&#x6848;&#x53EF;&#x7A3D;&#xFF1A; &#x66F4;&#x9AD8;&#x7684;&#x5149;&#x5408;&#x901F;&#x7387; &#xFF08;&#x4E3B; [CO2] &#x54CD;&#x5E94;&#xFF09; &#xFF1B;&#x589E;&#x52A0;&#x957F;&#x5EA6;&#x7684;&#x751F;&#x957F;&#x5B63;&#x8282; &#xFF08;&#x4E3B;&#x8981;&#x6E29;&#x5EA6;&#x54CD;&#x5E94;&#xFF09; &#xFF1B;&#x548C;&#x53F6;&#x9762;&#x79EF;&#x6307;&#x6570; &#xFF08;&#x4E3B;&#x8981; N &#x6C89;&#x79EF;&#x548C;&#x90E8;&#x5206; [CO2] &#x54CD;&#x5E94;&#xFF09; &#x8D8A;&#x9AD8;&#x3002;&#x5C06;&#x4F1A;&#x589E;&#x52A0;&#x571F;&#x58E4;&#x6709;&#x673A;&#x8D28;&#x589E;&#x52A0;&#x5783;&#x573E;&#x8F93;&#x5165;&#xFF0C;&#x867D;&#x7136;&#x542F;&#x52A8;&#x6700;&#x521D;&#xFF0C;&#x53EF;&#x80FD;&#x4F1A;&#x964D;&#x4F4E;&#x571F;&#x58E4; C &#x80A1;&#x7968;&#x4F46;&#x5783;&#x573E;&#x8D28;&#x91CF;&#x5F71;&#x54CD;&#x5E94;&#x8BE5;&#x5F88;&#x5C0F; &#xFF08;&#x54CD;&#x5E94; [CO2]&#x3001; N &#x6C89;&#x79EF;&#x548C;&#x6E29;&#x5EA6;&#xFF09; &#xFF1B;&#x5C06;&#x4F1A;&#x51CF;&#x5C11;&#x7531;&#x4E8E;&#x589E;&#x52A0;&#x6E29;&#x5EA6; &#xFF1B;&#x5E76;&#x5C06;&#x589E;&#x52A0;&#xFF0C;&#x56E0;&#x4E3A;&#x8FDF;&#x949D;&#x7684;&#x5206;&#x89E3;&#x4E0E; N &#x6C89;&#x79EF;&#xFF0C;&#x867D;&#x7136;&#x53EF;&#x4EE5;&#x589E;&#x52A0;&#x9AD8;&#x8D28;&#x91CF;&#x5783;&#x573E;&#x5206;&#x89E3;&#x7684;&#x901F;&#x5EA6;&#x548C;&#x4F4E;&#x8D28;&#x91CF;&#x7684;&#x5783;&#x573E;&#x5219;&#x4E0B;&#x8DCC;&#x3002;&#x5355;&#x56E0;&#x5B50;&#x7684;&#x54CD;&#x5E94;&#x53EF;&#x80FD;&#x4F1A;&#x4EA7;&#x751F;&#x8BEF;&#x5BFC;&#x7531;&#x4E8E;&#x76F8;&#x4E92;&#x4F5C;&#x7528;&#x56E0;&#x7D20;&#xFF0C;&#x7279;&#x522B;&#x662F;&#x90A3;&#x4E9B;&#x4E4B;&#x95F4; N &#x548C;&#x5176;&#x4ED6;&#x56E0;&#x7D20;&#xFF0C;&#x5982;&#x4ECE;&#x4F4E;&#x6E29;&#x8BF1;&#x5BFC;&#x5206;&#x89E3;&#x589E;&#x52A0; N &#x53EF;&#x7528;&#x6027;&#x7684;&#x95F4;&#x63A5;&#x5F71;&#x54CD;&#x3002;&#x957F;&#x671F;&#x5F3A;&#x5EA6;&#x7684;&#x53CD;&#x9988;&#xFF0C;&#x4F8B;&#x5982;&#x589E;&#x52A0;&#x7684;&#x9700;&#x6C42; N &#x589E;&#x957F;&#xFF0C;&#x4ECE;&#x5C06;&#x538B;&#x5012;&#x4E86;&#x5BF9;&#x5355;&#x4E00;&#x56E0;&#x7D20;&#x7684;&#x77ED;&#x671F;&#x53CD;&#x5E94;&#x3002;&#x4F46;&#x662F;&#xFF0C;&#x7BA1;&#x7406;&#x6709;&#x76F8;&#x5F53;&#x5927;&#x7684;&#x6F5C;&#x529B;&#xFF0C;&#x4E3A;&#x63A7;&#x5236; C &#x5B58;&#x50A8;&#x533A;&#x3002;

[CO2] &#x9AD8;&#x67B6;&#x3001; &#x6C2E;&#x6C89;&#x79EF;&#x3001; &#x589E;&#x52A0;&#x7684;&#x6E29;&#x5EA6;&#x548C;&#x78B3;&#x5438;&#x6536;&#x7684;&#x6E29;&#x5E26;&#x548C;&#x5317;&#x65B9;&#x68EE;&#x6797;&#x751F;&#x6001;&#x7CFB;&#x7EDF;&#x7BA1;&#x7406;&#x7684;&#x53EF;&#x80FD;&#x5F71;&#x54CD;&#xFF1A; &#x4E00;&#x4E2A;&#x6587;&#x732E;&#x7EFC;&#x8FF0;&#x3002;

Temperate and boreal forest ecosystems contain a large part of the carbon stored on land, in the form of both biomass and soil organic matter. Increasing atmospheric [CO2], increasing temperature, elevated nitrogen deposition and intensified management will change this C store. Well documented single-factor responses of net primary production are: higher photosynthetic rate (the main [CO2] response); increasing length of growing season (the main temperature response); and higher leaf-area index (the main N deposition and partly [CO2] response). Soil organic matter will increase with increasing litter input, although priming may decrease the soil C stock initially, but litter quality effects should be minimal (response to [CO2], N deposition, and temperature); will decrease because of increasing temperature; and will increase because of retardation of decomposition with N deposition, although the rate of decomposition of high-quality litter can be increased and that of low-quality litter decreased. Single-factor responses can be misleading because of interactions between factors, in particular those between N and other factors, and indirect effects such as increased N availability from temperature-induced decomposition. In the long term the strength of feedbacks, for example the increasing demand for N from increased growth, will dominate over short-term responses to single factors. However, management has considerable potential for controlling the C store.

The likely impact of elevated [CO2], nitrogen deposition, increased temperature and management on carbon sequestration in temperate and boreal forest ecosystems: a literature review.

Les &eacute;cosyst&egrave;mes de for&ecirc;ts temp&eacute;r&eacute;es et bor&eacute;ales contiennent une grande partie du carbone stock&eacute; sur terre, sous forme de biomasse et le sol des mati&egrave;res organiques. Augmentant atmosph&eacute;rique [CO2], lorsque la temp&eacute;rature augmente, les d&eacute;p&ocirc;ts d&#39;azote &eacute;lev&eacute;e et gestion renforc&eacute;e vont changer ce magasin C. Bien document&eacute; unifactorielle r&eacute;ponses du net sont de production primaire : taux de photosynth&egrave;se plus &eacute;lev&eacute; (la principale r&eacute;ponse [CO2]) ; augmentation de la longueur de la culture de saison (la r&eacute;ponse de la temp&eacute;rature principale) ; et indice de surface foliaire plus &eacute;lev&eacute; (les principaux d&eacute;p&ocirc;ts d&#39;azote et en partie [CO2] r&eacute;ponse). Mati&egrave;re organique du sol va augmenter avec l&#39;augmentation de port&eacute;e d&#39;entr&eacute;e, bien que l&#39;amor&ccedil;age peut diminuer le stock de C du sol au d&eacute;part, mais les effets de qualit&eacute; de la liti&egrave;re devraient &ecirc;tre minimes (r&eacute;ponse de [CO2], d&eacute;p&ocirc;ts d&#39;azote et la temp&eacute;rature) ; diminuera en raison de l&#39;augmentation de la temp&eacute;rature ; et augmentera en raison d&#39;un retard de d&eacute;composition avec les d&eacute;p&ocirc;ts d&#39;azote, bien que le taux de d&eacute;composition de la liti&egrave;re de qualit&eacute; peut &ecirc;tre augment&eacute; et celle de liti&egrave;re de basse qualit&eacute; a diminu&eacute;. Seul facteur r&eacute;ponses peuvent &ecirc;tre trompeur &agrave; cause des interactions entre les facteurs, en particulier ceux entre N et autres facteurs et des effets indirects tels que la disponibilit&eacute; accrue de N induite par la temp&eacute;rature de d&eacute;composition. &Agrave; long terme la force de r&eacute;troactions, par exemple la demande croissante de N de croissance accrue, dominera sur des r&eacute;actions &agrave; court terme aux facteurs simples. Cependant, la gestion a un potentiel consid&eacute;rable pour le contr&ocirc;le du magasin C.

L&#39;incidence probable d&#39;&eacute;lev&eacute;e [CO2], les d&eacute;p&ocirc;ts d&#39;azote, augmentation de la temp&eacute;rature et gestion sur la s&eacute;questration du carbone dans les &eacute;cosyst&egrave;mes des for&ecirc;ts temp&eacute;r&eacute;es et bor&eacute;ales : une revue de la litt&eacute;rature.

Gem&auml;&szlig;igten und borealen Wald-&Ouml;kosysteme enthalten einen Gro&szlig;teil der auf dem Land, in Form von Biomasse und Boden organische Substanz gespeicherten Kohlenstoff. Erh&ouml;hung der atmosph&auml;rischen [CO2], steigender Temperatur, &auml;ndert erh&ouml;hte Stickstoffdeposition und intensiveren Bewirtschaftung dieser C-Speicher sich. Gut dokumentiert einzigen Faktor Antworten net Prim&auml;rproduktion sind: h&ouml;here photosynthetische Rate (die wichtigsten [CO2] Antwort); L&auml;nge der wachsenden Jahreszeit (die wichtigsten Temperaturgang); und h&ouml;her Blatt-Bereich Index (die wichtigsten N-Ablagerung und teilweise [CO2] Reaktion). Organischer Substanzen im Boden erh&ouml;ht sich mit zunehmender Wurf Eingang, obwohl Grundierung kann den Boden C bestand zun&auml;chst verringern, aber Wurf hochwertige Effekte sollte minimal sein (Antwort auf [CO2], N-Ablagerung und Temperatur); aufgrund steigender Temperatur sinkt; und steigt wegen Retardierung der Zersetzung mit N-Ablagerung, obwohl die Rate der Zersetzung von qualitativ hochwertigen Wurf erh&ouml;ht werden kann und der minderwertige Wurf abgenommen. Einzigen Faktor Antworten k&ouml;nnen aufgrund von Wechselwirkungen zwischen Faktoren, insbesondere diejenigen zwischen N und andere Faktoren und indirekte Effekte wie erh&ouml;hte N-Verf&uuml;gbarkeit von Temperatur-induzierte Zersetzung irref&uuml;hrend sein. Langfristig wird die St&auml;rke der R&uuml;ckmeldungen, zum Beispiel die steigende Nachfrage nach N aus verst&auml;rktem Wachstum, &uuml;ber kurzfristige Reaktionen auf einzelne Faktoren dominieren. Allerdings hat die Verwaltung erhebliches Potenzial f&uuml;r die Steuerung des C-Store.

Die voraussichtlichen Auswirkungen der erh&ouml;hten [CO2], Stickstoffdeposition, erh&ouml;hte Temperatur und Management auf CO2-Sequestrierung in gem&auml;&szlig;igten und borealen Wald-&Ouml;kosysteme: eine Literatur&uuml;bersicht.

Ecosistemi di foreste temperate e boreali contengono una grande parte del carbonio immagazzinata sulla terra, sotto forma di biomassa sia del suolo, materia organica. [CO2] atmosferica in aumento, aumento della temperatura, deposizione di azoto elevato e gestione intensificata cambier&agrave; questo archivio C. Ben documentato fattore singolo risposte della rete di produzione primaria sono: alto tasso fotosintetico (la principale risposta [CO2]); aumentare la lunghezza di una crescente stagione (la risposta di temperatura principale); e il pi&ugrave; alto indice di superficie fogliare (il principale N deposizione e parzialmente risposta [CO2]). Materia organica del suolo aumenta con l&#39;aumento della cucciolata di ingresso, anche se innesco pu&ograve; diminuire lo stock di suolo C inizialmente, ma cucciolata di effetti di qualit&agrave; dovrebbero essere minimi (risposta a [CO2], deposizione N e temperatura); diminuir&agrave; a causa dell&#39;aumento di temperatura; e aumenter&agrave; a causa del ritardo della decomposizione con deposizione di N, sebbene il tasso di decomposizione della lettiera di alta qualit&agrave; pu&ograve; essere aumentato e quello di bassa qualit&agrave; cucciolata &egrave; diminuito. Risposte a fattore singolo possono essere fuorviante a causa delle interazioni tra fattori, in particolare quelli tra N e altri fattori e gli effetti indiretti come la maggiore disponibilit&agrave; di N da indotta da temperatura di decomposizione. A lungo termine la resistenza di feedback, ad esempio la crescente domanda per N da una crescita maggiore, dominer&agrave; sopra le risposte a breve termine ai singoli fattori. Tuttavia, gestione ha un potenziale considerevole per il controllo dell&#39;Archivio C.

Il probabile impatto di elevate [CO2], deposizione di azoto, aumento della temperatura e gestione sul sequestro del carbonio negli ecosistemi di foreste temperate e boreali: una rassegna della letteratura.

&#x6E29;&#x5E2F;&#x6797;&#x3068;&#x4E9C;&#x5BD2;&#x5E2F;&#x6797;&#x751F;&#x614B;&#x7CFB;&#x306B;&#x306F;&#x571F;&#x5730;&#x306B;&#x3001;&#x30D0;&#x30A4;&#x30AA;&#x30DE;&#x30B9;&#x304A;&#x3088;&#x3073;&#x571F;&#x58CC;&#x6709;&#x6A5F;&#x7269;&#x306E;&#x5F62;&#x3067;&#x683C;&#x7D0D;&#x3055;&#x308C;&#x3066;&#x70AD;&#x7D20;&#x306E;&#x5927;&#x90E8;&#x5206;&#x304C;&#x542B;&#x307E;&#x308C;&#x3066;&#x3044;&#x307E;&#x3059;&#x3002;&#x5927;&#x6C17; [CO2] &#x3092;&#x5897;&#x52A0;&#x3057;&#x3066;&#x3001;&#x6E29;&#x5EA6;&#x306E;&#x4E0A;&#x6607;&#x3001;&#x9AD8;&#x67B6;&#x306E;&#x7A92;&#x7D20;&#x6C88;&#x7740;&#x3068;&#x6FC0;&#x5316;&#x3055;&#x305B;&#x305F;&#x7BA1;&#x7406;&#x3053;&#x306E; C &#x30B9;&#x30C8;&#x30A2;&#x304C;&#x5909;&#x66F4;&#x3055;&#x308C;&#x307E;&#x3059;&#x3002;&#x3088;&#x304F;&#x4E00;&#x6B21;&#x751F;&#x7523;&#x3055;&#x308C;&#x3066;&#x30CD;&#x30C3;&#x30C8;&#x306E;&#x5358;&#x4E00;&#x56E0;&#x5B50;&#x5FDC;&#x7B54;&#x306E;&#x8A18;&#x8FF0;: &#x9AD8;&#x3044;&#x5149;&#x5408;&#x6210;&#x901F;&#x5EA6; (&#x30E1;&#x30A4;&#x30F3;&#x306E; [CO2] &#x5FDC;&#x7B54;);&#x6210;&#x9577;&#x306E;&#x9577;&#x3055;&#x3092;&#x5897;&#x3084;&#x3059;&#x30B7;&#x30FC;&#x30BA;&#x30F3; (&#x30E1;&#x30A4;&#x30F3;&#x6E29;&#x5EA6;&#x5FDC;&#x7B54;);&#x4E0A;&#x4F4D;&#x306E;&#x8449;&#x9762;&#x7A4D;&#x6307;&#x6570; (&#x30E1;&#x30A4;&#x30F3; N &#x6C88;&#x7740;&#x3068;&#x90E8;&#x5206;&#x7684; [CO2] &#x5FDC;&#x7B54;)&#x3002;&#x571F;&#x58CC;&#x6709;&#x6A5F;&#x7269;&#x306F;&#x3001;&#x30EA;&#x30BF;&#x30FC; &#x30D7;&#x30E9;&#x30A4;&#x30DF;&#x30F3;&#x30B0;&#x306F;&#x5F53;&#x521D;&#x3001;&#x571F;&#x58CC; C &#x5728;&#x5EAB;&#x3092;&#x6E1B;&#x3089;&#x3059;&#x304B;&#x3082;&#x3057;&#x308C;&#x306A;&#x3044;&#x304C;&#x3001;&#x30EA;&#x30BF;&#x30FC;&#x54C1;&#x8CEA;&#x306E;&#x30A8;&#x30D5;&#x30A7;&#x30AF;&#x30C8;&#x3092;&#x6700;&#x5C0F;&#x9650;&#x306B;&#x3059;&#x308B;&#x5FC5;&#x8981;&#x304C;&#x3042;&#x308A;&#x307E;&#x3059;&#x304C;&#x3001;&#x5165;&#x529B; ([CO2] &#x3078;&#x306E;&#x5FDC;&#x7B54;&#x3001;N &#x6C88;&#x7740;&#x304A;&#x3088;&#x3073;&#x6E29;&#x5EA6;); &#x306E;&#x5897;&#x52A0;&#x306B;&#x4F34;&#x3063;&#x3066;&#x5897;&#x52A0;&#x3057;&#x307E;&#x3059;&#x6E29;&#x5EA6;&#x306E;&#x4E0A;&#x6607;&#x306B;&#x3088;&#x308A;&#x6E1B;&#x5C11;&#x3059;&#x308B;;&#x9AD8;&#x54C1;&#x8CEA;&#x306E;&#x30EA;&#x30BF;&#x30FC;&#x306E;&#x5206;&#x89E3;&#x901F;&#x5EA6;&#x3092;&#x5897;&#x52A0;&#x3059;&#x308B;&#x3053;&#x3068;&#x304C;&#x3067;&#x304D;&#x3001;&#x4F4E;&#x54C1;&#x8CEA;&#x306E;&#x3054;&#x307F;&#x306F;&#x6E1B;&#x5C11;&#x3057;&#x305F;&#x304C;&#x9045;&#x6EDE; N &#x6C88;&#x7740;&#x3068;&#x5206;&#x89E3;&#x306E;&#x305F;&#x3081;&#x5897;&#x52A0;&#x3057;&#x307E;&#x3059;&#x3002;&#x5358;&#x4E00;&#x56E0;&#x5B50;&#x5FDC;&#x7B54;&#x7279;&#x5B9A;&#x306E;&#x8981;&#x56E0;&#x9593;&#x306E;&#x76F8;&#x4E92;&#x4F5C;&#x7528;&#x306E;&#x305F;&#x3081;&#x305D;&#x308C;&#x3089;&#x306E; N &#x305D;&#x306E;&#x4ED6;&#x306E;&#x8981;&#x56E0;&#x3068;&#x6E29;&#x5EA6;&#x8A98;&#x8D77;&#x5206;&#x89E3;&#x304B;&#x3089; N &#x306E;&#x53EF;&#x7528;&#x6027;&#x3092;&#x5411;&#x4E0A;&#x306A;&#x3069;&#x306E;&#x9593;&#x63A5;&#x52B9;&#x679C;&#x3068;&#x8AA4;&#x89E3;&#x3055;&#x308C;&#x308B;&#x3053;&#x3068;&#x304C;&#x3067;&#x304D;&#x307E;&#x3059;&#x3002;&#x9577;&#x671F;&#x7684;&#x306B;&#x30D5;&#x30A3;&#x30FC;&#x30C9;&#x30D0;&#x30C3;&#x30AF;&#x3001;&#x305F;&#x3068;&#x3048;&#x3070; N &#x306E;&#x5897;&#x52A0;&#x9700;&#x8981;&#x5897;&#x52A0;&#x306E;&#x6210;&#x9577;&#x304B;&#x3089;&#x306E;&#x5F37;&#x5EA6;&#x77ED;&#x671F;&#x30EC;&#x30B9;&#x30DD;&#x30F3;&#x30B9;&#x5358;&#x4E00;&#x8981;&#x56E0;&#x3092;&#x652F;&#x914D;&#x3059;&#x308B;&#x3067;&#x3057;&#x3087;&#x3046;&#x3002;&#x305F;&#x3060;&#x3057;&#x3001;&#x7BA1;&#x7406; C &#x30B9;&#x30C8;&#x30A2;&#x3092;&#x5236;&#x5FA1;&#x3059;&#x308B;&#x305F;&#x3081;&#x306E;&#x304B;&#x306A;&#x308A;&#x306E;&#x53EF;&#x80FD;&#x6027;&#x304C;&#x3042;&#x308A;&#x307E;&#x3059;&#x3002;

&#x9AD8;&#x67B6; [CO2]&#x3001;&#x7A92;&#x7D20;&#x6C88;&#x7740;&#x3001;&#x6E29;&#x5EA6;&#x4E0A;&#x6607;&#x3001;&#x6E29;&#x5E2F;&#x6797;&#x3068;&#x4E9C;&#x5BD2;&#x5E2F;&#x68EE;&#x6797;&#x751F;&#x614B;&#x7CFB;&#x306B;&#x304A;&#x3051;&#x308B;&#x70AD;&#x7D20;&#x9694;&#x96E2;&#x306B;&#x5BFE;&#x3059;&#x308B;&#x7BA1;&#x7406;&#x306E;&#x53EF;&#x80FD;&#x6027;&#x3078;&#x306E;&#x5F71;&#x97FF;&#xFF1A; &#x6587;&#x732E;&#x30EC;&#x30D3;&#x30E5;&#x30FC;&#x3002;

&#xC628;&#xB300;&#xC640; &#xC544; &#xD55C; &#xB300; &#xC0B0;&#xB9BC; &#xC0DD;&#xD0DC;&#xACC4;&#xB294; &#xBC14;&#xC774;&#xC624; &#xB9E4;&#xC2A4;&#xC640; &#xD1A0;&#xC591; &#xC720;&#xAE30; &#xBB3C;&#xC9C8;&#xC758; &#xD615;&#xD0DC;&#xB85C; &#xD1A0;&#xC9C0;&#xC5D0; &#xC800;&#xC7A5; &#xB41C; &#xD0C4;&#xC18C;&#xC758; &#xC0C1;&#xB2F9; &#xBD80;&#xBD84; &#xD3EC;&#xD568; &#xB418;&#xC5B4; &#xC788;&#xC2B5;&#xB2C8;&#xB2E4;. &#xB300;&#xAE30; c o [2]&#xB97C; &#xC99D;&#xAC00;, &#xC99D;&#xAC00; &#xD558;&#xB294; &#xC628;&#xB3C4;, &#xB192;&#xC740; &#xC9C8;&#xC18C; &#xC99D; &#xCC29; &#xBC0F; &#xAC15;&#xD654; &#xD558; &#xACE0; &#xAD00;&#xB9AC;&#xAC00; C &#xC800;&#xC7A5;&#xC18C;&#xB97C; &#xBCC0;&#xACBD; &#xB429;&#xB2C8;&#xB2E4;. &#xC798; &#xBB38;&#xC11C;&#xD654; &#xC8FC; &#xC0DD;&#xC0B0;&#xC740; &#xADF8;&#xBB3C;&#xC758; &#xB2E8;&#xC77C; &#xC694;&#xC18C; &#xC751;&#xB2F5;: &#xB192;&#xC740; &#xAD11;&#xD569;&#xC131; &#xC18D;&#xB3C4; (&#xBA54;&#xC778; [CO2] &#xC751;&#xB2F5;); (&#xC8FC;&#xC694; &#xC628;&#xB3C4; &#xC751;&#xB2F5;); &#xC2DC;&#xC98C; &#xC131;&#xC7A5;&#xC758; &#xAE38;&#xC774; &#xC99D;&#xAC00; &#xADF8;&#xB9AC;&#xACE0; &#xB192;&#xC740; &#xB9AC;&#xD504; &#xC9C0;&#xC5ED; &#xC778;&#xB371;&#xC2A4; (&#xBA54;&#xC778; N &#xC99D; &#xCC29; &#xBC0F; &#xBD80;&#xBD84;&#xC801;&#xC73C;&#xB85C; [CO2] &#xC751;&#xB2F5;). &#xD1A0;&#xC591; &#xC720;&#xAE30; &#xBB3C; &#xC4F0;&#xB808;&#xAE30; &#xBABB;&#xC4F0;&#xAC8C; &#xD1A0;&#xC591; C &#xC8FC;&#xC2DD;&#xC744; &#xCC98;&#xC74C;&#xC5D0;, &#xC904;&#xC77C; &#xC218; &#xC788;&#xC9C0;&#xB9CC; &#xC4F0;&#xB808;&#xAE30; &#xD488;&#xC9C8; &#xD6A8;&#xACFC; &#xCD5C;&#xC18C;&#xD654; &#xD574;&#xC57C; &#xC785;&#xB825; ([c o 2]&#xC5D0; &#xB300; &#xD55C; &#xC751;&#xB2F5;, N &#xC99D; &#xCC29; &#xBC0F; &#xC628;&#xB3C4;) &#xC99D;&#xAC00; &#xD568;&#xAED8; &#xC99D;&#xAC00;&#xD560; &#xAC83; &#xC774;&#xB2E4; &#xC628;&#xB3C4;; &#xC99D;&#xAC00;&#xB85C; &#xC778;&#xD574; &#xC904;&#xC5B4; &#xADF8;&#xB9AC;&#xACE0; &#xB192;&#xC740; &#xC218;&#xC900;&#xC758; &#xC4F0;&#xB808;&#xAE30;&#xC758; &#xBD84;&#xD574; &#xC18D;&#xB3C4; &#xC99D;&#xAC00; &#xC2DC;&#xD0AC; &#xC218; &#xC788;&#xC9C0;&#xB9CC; &#xB0AE;&#xC740; &#xD488;&#xC9C8; &#xC4F0;&#xB808;&#xAE30;&#xC758; &#xAC10;&#xC18C; N &#xC99D; &#xCC29;&#xACFC; &#xBD84;&#xD574;&#xC758; &#xC9C0;&#xCCB4; &#xB54C;&#xBB38;&#xC5D0; &#xC99D;&#xAC00;&#xD560; &#xAC83; &#xC774;&#xB2E4;. &#xB2E8;&#xC77C; &#xC694;&#xC18C; &#xC751;&#xB2F5; &#xC218; &#xC218; &#xC798;&#xBABB; &#xD2B9;&#xD788;&#xC5D0;&#xC11C; &#xC694;&#xC18C; &#xC0AC;&#xC774;&#xC758; &#xC0C1;&#xD638; &#xC791;&#xC6A9; &#xB54C;&#xBB38;&#xC5D0; N &#xBC0F; &#xB2E4;&#xB978; &#xC694;&#xC778; &#xBC0F; &#xBD84;&#xD574; &#xC628;&#xB3C4; &#xC720;&#xB3C4;&#xC5D0;&#xC11C; N &#xAC00;&#xC6A9;&#xC131; &#xC99D;&#xB300; &#xB4F1; &#xAC04;&#xC811; &#xD6A8;&#xACFC; &#xC0AC;&#xC774;. &#xC7A5;&#xAE30;&#xC801;&#xC73C;&#xB85C; &#xD53C;&#xB4DC;&#xBC31;, &#xC608;&#xB97C; &#xB4E4;&#xC5B4; N&#xC5D0; &#xB300; &#xD55C; &#xC99D;&#xAC00; &#xB41C; &#xC131;&#xC7A5;&#xC5D0;&#xC11C; &#xC99D;&#xAC00; &#xC218;&#xC694;&#xC758; &#xAC15;&#xB3C4; &#xB2E8;&#xC77C; &#xC694;&#xC778; &#xB2E8;&#xAE30; &#xC751;&#xB2F5;&#xC744; &#xD1B5;&#xD574; &#xC9C0;&#xBC30;&#xD560; &#xAC83; &#xC774;&#xB2E4;. &#xADF8;&#xB7EC;&#xB098;, &#xAD00;&#xB9AC; C &#xC0C1;&#xC810;&#xC744; &#xC81C;&#xC5B4; &#xD558;&#xAE30; &#xC704;&#xD55C; &#xC0C1;&#xB2F9;&#xD55C; &#xC7A0;&#xC7AC;&#xB825;&#xC744;&#xAC00;&#xC9C0;&#xACE0;.

&#xC0C1;&#xC2B9; &#xB41C; &#xAD8C;&#xD55C; [CO2], &#xC9C8;&#xC18C; &#xC99D; &#xCC29;, &#xC99D;&#xAC00; &#xB41C; &#xC628;&#xB3C4; &#xC628;&#xB300;&#xC640; &#xC544; &#xD55C; &#xB300; &#xC0B0;&#xB9BC; &#xC0DD;&#xD0DC;&#xACC4;&#xC5D0; &#xD0C4;&#xC18C; &#xACA9;&#xB9AC;&#xC5D0; &#xB300; &#xD55C; &#xAD00;&#xB9AC;&#xC758; &#xAC00;&#xB2A5;&#xC131;&#xC774; &#xC601;&#xD5A5;: &#xBB38;&#xD559;&#xC758; &#xAC80;&#xD1A0;.

Ecosistemas de bosques templados y boreales contienen gran parte del carbono almacenado en la tierra, en forma de biomasa y el suelo de materia org&aacute;nica. Aumento atmosf&eacute;rico [CO2], aumento de temperatura, deposici&oacute;n de nitr&oacute;geno elevado y gesti&oacute;n intensificada cambiar&aacute; esta tienda C. Bien documentado respuestas solo factor de red son de producci&oacute;n primaria: tasa fotosint&eacute;tica (la principal respuesta [CO2]); aumento de longitud de crecimiento de la temporada (la respuesta de la temperatura principal); y el mayor &iacute;ndice de &aacute;rea foliar (deposici&oacute;n de N principal y en parte respuesta [CO2]). Materia org&aacute;nica del suelo aumenta con el aumento de la camada de entrada, aunque cebado puede disminuir la acci&oacute;n de C en el suelo al principio, pero la camada calidad efectos deben ser m&iacute;nimos (respuesta a [CO2], la deposici&oacute;n de N y temperatura); disminuir&aacute; debido a aumento de temperatura; y aumentar&aacute; debido a retraso de descomposici&oacute;n con la deposici&oacute;n de N, aunque se puede aumentar la tasa de descomposici&oacute;n de la basura de alta calidad y de baja calidad camada disminuido. Las respuestas solo factor pueden ser enga&ntilde;osa debido a las interacciones entre factores, en particular entre N y otros factores y efectos indirectos como la mayor disponibilidad de N de descomposici&oacute;n por temperatura. A la larga la fuerza de los votos, por ejemplo la creciente demanda de N de mayor crecimiento, dominar&aacute; sobre respuestas a corto plazo a factores individuales. Sin embargo, la gerencia tiene un potencial considerable para el control de la tienda de C.

El probable impacto de elevado [CO2], deposici&oacute;n de nitr&oacute;geno, aumentada de la temperatura y gesti&oacute;n en el secuestro de carbono en ecosistemas de bosques templados y boreales: una revisi&oacute;n de literatura.

This study presents new evidence that radiocarbon, combined with dendrochronological and stable isotopes analysis in tree rings and needles, can help to better understand the influence of pollution on trees. Pinus pinea individuals, adjacent to main roads in the urban area of Caserta (South Italy) and exposed to large amounts of traffic exhaust since 1980, were sampled and the time-related trend in the growth residuals was estimated. We found a consistent decrease in the ring width starting from 1980, with a slight increase in delta(13)C value, which was considered to be a consequence of environmental stress. No clear pattern was identified in delta(15)N, while an increasing effect of the fossil fuel dilution on the atmospheric bomb-enriched (14)C background was detected in tree rings, possibly as a consequence of the increase in traffic exhausts. Our findings suggested that radiocarbon is a very sensitive tool to investigate small-scale (i.e. traffic exhaust at the level crossing) and large-scale (urban area pollution) induced disturbances.

Traffic pollution affects tree-ring width and isotopic composition of Pinus pinea.

Biochar (BC) application to agricultural soils could potentially sequester recalcitrant C, increase N retention, increase water holding capacity, and decrease greenhouse gas (GHG) emissions. Biochar addition to soils can alter soil N cycling and in some cases decrease extractable mineral N (NO and NH) and NO emissions. These benefits are not uniformly observed across varying soil types, N fertilization, and BC properties. To determine the effects of BC addition on N retention and GHG flux, we added two sizes (>250 and <250 µm) of oak-derived BC (10% w/w) to two soils (aridic Argiustoll and aquic Haplustoll) with and without N fertilizer and measured extractable NO and NH and GHG efflux (NO, CO, and CH) in a 123-d laboratory incubation. Biochar had no effect on NO, NH, or NO in the unfertilized treatments of either soil. Biochar decreased cumulative extractable NO in N fertilized treatments by 8% but had mixed effects on NH. Greenhouse gas efflux differed substantially between the two soils, but generally with N fertilizer BC addition decreased NO 3 to 60%, increased CO 10 to 21%, and increased CH emissions 5 to 72%. Soil pH and total treatment N (soil + fertilizer + BC) predicted soil NO flux well across these two different soils. Expressed as CO equivalents, BC significantly reduced GHG emissions only in the N-fertilized silt loam by decreasing NO flux. In unfertilized soils, CO was the dominant GHG component, and the direction of the flux was mediated by positive or negative BC effects on soil CO flux. On the basis of our data, the use of BC appears to be an effective management strategy to reduce N leaching and GHG emissions, particularly in neutral to acidic soils with high N content.

Biochar and nitrogen fertilizer alters soil nitrogen dynamics and greenhouse gas fluxes from two temperate soils.

The decomposition and transformation of above- and below-ground plant detritus (litter) is the main process by which soil organic matter (SOM) is formed. Yet, research on litter decay and SOM formation has been largely uncoupled, failing to provide an effective nexus between these two fundamental processes for carbon (C) and nitrogen (N) cycling and storage. We present the current understanding of the importance of microbial substrate use efficiency and C and N allocation in controlling the proportion of plant-derived C and N that is incorporated into SOM, and of soil matrix interactions in controlling SOM stabilization. We synthesize this understanding into the Microbial Efficiency-Matrix Stabilization (MEMS) framework. This framework leads to the hypothesis that labile plant constituents are the dominant source of microbial products, relative to input rates, because they are utilized more efficiently by microbes. These microbial products of decomposition would thus become the main precursors of stable SOM by promoting aggregation and through strong chemical bonding to the mineral soil matrix.

The Microbial Efficiency-Matrix Stabilization (MEMS) framework integrates plant litter decomposition with soil organic matter stabilization: do labile plant inputs form stable soil organic matter?

Increasing human demands on soil-derived ecosystem services requires reliable data on global soil resources for sustainable development. The soil organic carbon (SOC) pool is a key indicator of soil quality as it affects essential biological, chemical and physical soil functions such as nutrient cycling, pesticide and water retention, and soil structure maintenance. However, information on the SOC pool, and its temporal and spatial dynamics is unbalanced. Even in well-studied regions with a pronounced interest in environmental issues information on soil carbon (C) is inconsistent. Several activities for the compilation of global soil C data are under way. However, different approaches for soil sampling and chemical analyses make even regional comparisons highly uncertain. Often, the procedures used so far have not allowed the reliable estimation of the total SOC pool, partly because the available knowledge is focused on not clearly defined upper soil horizons and the contribution of subsoil to SOC stocks has been less considered. Even more difficult is quantifying SOC pool changes over time. SOC consists of variable amounts of labile and recalcitrant molecules of plant, and microbial and animal origin that are often operationally defined. A comprehensively active soil expert community needs to agree on protocols of soil surveying and lab procedures towards reliable SOC pool estimates. Already established long-term ecological research sites, where SOC changes are quantified and the underlying mechanisms are investigated, are potentially the backbones for regional, national, and international SOC monitoring programs.

M. Francesca Cotrufo

Natural Resource Ecology Laboratory,
Department of Soil and Crop Sciences

Colorado State University

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

M. Francesca Cotrufo

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Natural Resource Ecology Laboratory,Department of Soil and Crop Sciences

Colorado State University

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

Natural Resource Ecology Laboratory,
Department of Soil and Crop Sciences

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