J. 2014. Organic carbon and nitrogen stocks in a clay loam soil 10 years after a single compost application. Can. J. Soil. Sci. 94: 357Á363. Household food waste compost (FWC), yard waste compost (YWC) and pig manure plus wheat straw compost (PMC) were applied once in the fall of 1998 to a Brookston clay loam soil in southwestern Ontario to determine immediate and long-term effects of organic amendments on soil quality and productivity. In this report, we describe the residual effects of these single compost applications on soil organic carbon (SOC) and total soil nitrogen (TN) stocks 10 yr after compost addition (2009). FWC was applied at 75 Mg ha (1 , 150 Mg ha (1 and 300 Mg ha (1 , while YWC and PMC were applied at the single rate of 75 Mg ha (1 . The 75 Mg ha (1 additions of YWC, PMC and FWC increased SOC in the top 30 cm relative to a control (no compost additions) by 12.3% (9.0 Mg ha (1 ), 16.6% (12.2 Mg ha (1 ) and 0%, respectively; and they increased TN relative to the control by 8.0% (0.53 Mg ha (1 ), 11.7% (0.77 Mg ha (1 ), and 0%, respectively. The 150 and 300 Mg ha (1 additions of FWC increased SOC in the top 30 cm by 13.0 and 24.7 Mg ha (1 , respectively, and they increased TN by 0.93 and 1.70 Mg ha (1 , respectively. These results indicate that increases in SOC and TN stocks accruing from a single compost addition can persist for at least a decade, but the degree of increase depends strongly on compost type and addition rate. It was concluded that high compost addition rates of FWC and/or addition of composts derived from recalcitrant organic materials may be a good strategy for achieving long-term carbon and nitrogen sequestration in the cool, humid fine-textured soils of southwestern Ontario. , J. 2014. Re´serves de carbone organique et d'azote dans un loam argileux dix ans apre`s une seule application de compost. Can. J. Soil. Sci. 94: 357Á363. À l'automne 1998, du compost de de´chets alimentaires domestiques (CDA), de re´sidus de jardinage (CRJ) et de fumier de porc meˆle´a`de la paille de ble´(CFP) ont e´te´applique´une seule fois a`un loam argileux Brookston dans le sud-ouest de l'Ontario. L'expe´rience devait e´tablir les effets imme´diats et prolonge´s de ces amendements organiques sur la qualite´et la productivite´du sol. Le pre´sent article de´crit les effets re´siduels de ces applications uniques sur les stocks de carbone organique du sol (COS) et d'azote total (AT), dix ans apre`s l'amendement (2009). Le CDA a e´te´applique´a`raison de 75 Mg, 150 Mg et 300 Mg par hectare, tandis que le CRJ et le CFP l'ont e´te´au meˆme taux de 75 Mg par hectare. Comparativement a`la parcelle te´moin (aucun amendement), l'addition de 75 Mg de CRJ, de CFP et de CDA a respectivement augmente´la concentration de COS dans la couche supe´rieure de 30 cm du sol de 12,3 % (9,0 Mg par hectare), de 16,6 % (12,2 Mg par hectare) et de 0 %; paralle`lement, elle a accru respectivement la quantite´d'AT de 8,0 % (0,53 Mg par hectare), de 11,7 % (0,77 Mg par hectare) et de 0 %, par rapport a`celle releve´e dans la parcel...

X. M. 2015. Temporal effects of food waste compost on soil physical quality and productivity. Can. J. Soil Sci. 95: 251Á268. The benefits of compost additions on soil organic carbon content and crop productivity are extant in the literature, but detailed studies of compost effects on soil physical quality (SPQ) are limited. The objective of this study was therefore to describe how one-time additions of compost impact the immediate, mid-term and long-term SPQ and crop yields of an agricultural soil. Food waste compost (FWC) was incorporated once into the top 10 cm of a humid-temperate Brookston clay loam soil at rates of 0 (Control), 75 dry t ha(1 (FWC-75), 150 dry t ha(1 (FWCÁ150) and 300 dry t ha (1 (FWC-300); measurements of SPQ parameters and corn yield were then made annually over the next 11 yr. The SPQ parameters included bulk density (BD), organic carbon content (OC), air capacity (AC), plant-available water capacity (PAWC), relative field capacity (RFC), and saturated hydraulic conductivity (K S ), which were obtained from intact (undisturbed) soil core samples. Prior to compost addition, BD, OC, AC, PAWC, RFC and K S were substantially non-optimal, and BD had increased relative to virgin soil by 46%, while OC, AC and PAWC had decreased relative to virgin soil by 60, 56 and 43%, respectively. Improvements in SPQ 1 yr after compost addition were negligible or small for FWC-75 and FWC-150, but FWC-300 generated optimal values for BD, OC, AC, PAWC and RFC. The SPQ parameters degraded with time, but 11 yr after compost addition, OC and AC under FWC-300 were still within their optimal ranges, as well as significantly (PB0.05) greater than the Control values by 65 and 26%, respectively. Soil cracks and biopores apparently induced substantial annual variation in K S , but average K S nevertheless increased with increasing compost addition rate. Corn grain yield varied substantially among years, which was likely due to weather and compost effects; however, 11-yr cumulative yields from the compost treatments were greater than the Control by 2200Á6500 kg ha (1 .

Influence of compost source on corn grain yields, nitrous oxide and carbon dioxide emissions in southwestern Ontario. Can. J. Soil Sci. 94: 347Á355. The impacts of compost type on corn grain yields over 10 yr and N 2 O and CO 2 emissions in the first 3 yr after compost application were evaluated on a Brookston clay loam soil in Woodslee, ON. The treatments included yard waste compost (YWC), kitchen food waste compost (FWC), and pig manure compost (PMC), which were applied once in the fall of 1998 to field plots at a rate of 75 Mg ha (1 (dry weight basis) and no further applications occurred thereafter as well as a fertilized control treatment. Large application rates were examined to see if the various compost sources could have a lasting effect on soil C storage, N 2 O and CO 2 emissions and corn yields. Compost application significantly increased corn grain yields by 12.9 to 19.4% over 3 yr. However, after 10 yr, FWC was the only compost source which significantly increased yields by 11.3% compared with the fertilized control. Emissions of N 2 O and CO 2 varied with compost type, soil water content and time. Greater N 2 O emissions occurred in 1999 from PMC (5.4 kg N ha (1 ) than YWC (2.7 kg N ha (1 ) and FWC (1.3 kg N ha (1 ); however, the N 2 O emissions from the PMC were less than from YWC and FWC in 2001. The 3-yr average N 2 O emissions were significantly greater with PMC (2.7 kg N ha (1 ) and YWC (2.5 kg N ha (1 ) compared with the control (1.5 kg N ha (1 ). Hence, the timing of N 2 O emissions varied by compost type, but the overall losses were similar as the higher N 2 O losses in the first year with PMC were offset by the reduced losses with PMC in the third year. Significantly more CO 2 was produced from the FWC in 2000 and from PMC in 2001 than the control. Fleming, R. et Denholme, K. 2014. Influence de la source de compost sur le rendement du maı¨s-grain ainsi que sur les e´missions d'oxyde nitreux et de dioxyde de carbone dans le sud-ouest de l'Ontario. Can. J. Soil Sci. 94: 347Á355. Les auteurs ont de´termine´quel impact la nature du compost a eu sur le rendement du maı¨s-grain pendant dix ans, ainsi que sur les e´missions de N 2 O et de CO 2 durant les trois anne´es suivant l'amendement d'un loam argileux Brookston situe´a`Woodslee, en Ontario. Les traitements e´taient les suivants : compost de re´sidus de jardinage (CRJ), compost de de´chets alimentaires (CDA) et compost de fumier de porc (CFP) applique´s une seule fois a`des parcelles sur le terrain, a`l'automne 1998, a`raison de 75 Mg par hectare (poids sec). Aucune autre application n'a e´te´effectue´e par la suite; une parcelle fertilise´e servait de te´moin. On a opte´pour un taux d'application e´leve´en vue d'e´tablir si le type de compost exerce un effet durable sur le stockage du C dans le sol, sur les de´gagements de N 2 O et de CO 2 , et sur le rendement du maı¨s. L'application de compost a augmente´significativement le rendement du maı¨s-grain pendant trois ans, soit de 12,9 a`19,4 %. Apre`s dix ans toutefois, seul le CDA avait accru ...

Wang, Y. T., Zhang, T. Q., Hu, Q. C., O'Halloran, I. P., Tan, C. S. and Reid, K. 2011. Temporal patterns of soil phosphorus release to runoff during a rainfall event as influenced by soil properties and its effects on estimating soil P losses. Can. J. Soil Sci. 91: 339–347. The phosphorus (P) released in soil runoff during a rainfall event varies as labile P is depleted, and the dynamic pattern can be a function of soil P content and other soil properties. This study was conducted to determine the temporal pattern of runoff dissolved reactive P (DRP) concentration during a simulated rainfall event and the controlling soil properties. Soil samples were collected from six soil types across the province of Ontario, with 10 sites for each, to provide a wide range of soil test P (STP) levels. The instantaneous DRP concentration in surface runoff created during the rainfall event could be predicted by time t (min, since the onset of surface runoff) through a power function: DRP=αt−β, where α and β are constants representing initial potential of soil P release to runoff as DRP at the onset of surface runoff and DRP decrease rate with time, respectively. The values of α and β for a given soil could be determined by DPSM3-2 (Mehlich-3 P/Mehlich-3 Al) using the following formulas:[Formula: see text] The description of the temporal pattern of runoff DRP concentration during a rainfall event with the constants estimated using DPSM3−2 can aid in the prediction of soil runoff DRP loss.