Biochar-manure changes N mineralization in a Gray Luvisol used for agricultural production

Author(s):  
Tien Luo Ying Weber ◽  
Carlos M Romero ◽  
M. Derek MacKenzie

Biochar is a source of stable organic matter being explored as a manure additive. A 64-day incubation experiment was conducted to quantify the short-term effect of manure (RM), biochar-manure (BM), raw biochar (BC), RM + BC, and BM + BC amendment on soil carbon (C) and nitrogen (N) mineralization. Manure increased CO2-C emission rates, with the highest cumulative CO2-C emissions being observed for RM + BC. Treatments with BM halted soil C mineralization, indicating manure-C stabilization. By contrast, neither RM nor BM affected soil N mineralization. Applying BM might benefit soil C sequestration by lowering CO2-C emissions over the long-term.

Soil Research ◽  
2012 ◽  
Vol 50 (5) ◽  
pp. 380 ◽  
Author(s):  
Jorge Sierra ◽  
Natacha Motisi

Several long-term studies on tropical soils have shown that legume residue incorporation increases soil nitrogen (N) sequestration more than that of carbon (C), resulting in a fall in the C/N ratio. This study was designed to assess the short-term effect of legume litter addition on N supply and the long-term effect on soil organic matter (SOM) formation and soil C/N decrease. The long-term effect was evaluated in a 2-year mesocosm experiment with high and frequent organic inputs from two types of legume litter with different C/N ratios, using stable isotope techniques. The short-term effect of litter was analysed using four different litters in 3-month laboratory incubations. A model of litter decomposition was used to describe C and N kinetics in the laboratory experiment and to verify whether the long-term effect of litter may be predicted from short-term incubations. The results of the mesocosm experiment confirmed that legume inputs increased soil organic N (mean +21%) more than organic C (mean +15%) (P = 0.05). Although no differences between litters were observed for C dynamics, N sequestration (14% and 28%) and the final soil C/N (12.0 and 10.8) varied with litter C/N (34.4 and 16.1, respectively). The laboratory experiment and model outputs confirmed these findings and indicated that the higher N sequestration was due to a change in the parameters describing humification of C and N coming from litter. This change depended on litter quality and was greater for litters with low C/N—C humification 0.66 g C g–1 C and N humification 0.76 g N g–1 N for litter C/N 16.1. Carbon and N sequestration were greater in the laboratory experiment, due to a higher mineralisation of the new SOM derived from litter in the mesocosm experiment—32% and 15% for the mesocosm and the laboratory experiments, respectively. Our results indicated that the decrease in soil C/N and the rapid mineralisation of new SOM should be considered in models of litter decomposition to respond correctly to the long- and the short-term effects of legume litter inputs in tropical soils.


2003 ◽  
Vol 182 (5) ◽  
pp. 412-419 ◽  
Author(s):  
Peter J. Cooper ◽  
Lynne Murray ◽  
Anji Wilson ◽  
Helena Romaniuk

BackgroundPsychological interventions for postnatal depression can be beneficial in the short term but their longer-term impact is unknown.AimsTo evaluate the long-term effect on maternal mood of three psychological treatments in relation to routine primary care.MethodWomen with post-partum depression (n=193) were assigned randomly to one of four conditions: routine primary care, non-directive counselling, cognitive–behavioural therapy or psychodynamic therapy. They were assessed immediately after the treatment phase (at 4.5 months) and at 9, 18 and 60 months post-partum.ResultsCompared with the control, all three treatments had a significant impact at 4.5 months on maternal mood (Edinburgh Postnatal Depression Scale, EPDS). Only psychodynamic therapy produced a rate of reduction in depression (Structured Clinical Interview for DSM–III–R) significantly superior to that of the control. The benefit of treatment was no longer apparent by 9 months post-partum. Treatment did not reduce subsequent episodes of post-partum depression.ConclusionsPsychological intervention for post-partum depression improves maternal mood (EPDS) in the short term. However, this benefit is not superior to spontaneous remission in the long term.


Author(s):  
Signe Hulsbæk ◽  
Carsten Juhl ◽  
Alice Røpke ◽  
Thomas Bandholm ◽  
Morten Tange Kristensen

Abstract Background A systematic review and meta-analysis was performed to evaluate the short- and long-term effect of exercise therapy on physical function, independence and wellbeing in older patients following hip fracture, and secondly, whether the effect was modified by trial level characteristics such as intervention modality, duration and initiation timepoint. Methods Medline, CENTRAL, Embase, CINAHL and PEDro was searched up-to November 2020. Eligibility criteria was randomized controlled trials investigating the effect of exercise therapy on physical function, independence and wellbeing in older patients following hip fracture, initiated from time of surgery up-to 1-year. Results Forty-nine studies involving 3905 participants showed a small to moderate effect of exercise therapy at short term (end of intervention) on mobility (Standardized mean difference, SMD 0.49, 95%CI 0.22-0.76); Activities of Daily Living (ADL) (SMD 0.31, 95%CI 0.16-0.46); lower limb muscle strength (SMD 0.36, 95%CI 0.13-0.60); balance (SMD 0.34, 95%CI 0.14-0.54). At long term (closest to 1-year), small to moderate effects were found for mobility (SMD 0.74, 95%CI 0.15-1.34); ADL (SMD 0.42, 95%CI 0.23-0.61); balance (SMD 0.50, 95%CI 0.07-0.94) and Health related Quality of Life (HRQoL) (SMD 0.31, 95%CI 0.03-0.59). Certainty of evidence was evaluated using GRADE ranging from moderate to very low, due to study limitation and inconsistency. Conclusion We found low certainty of evidence for a moderate effect of exercise therapy on mobility in older patients following hip fracture at end-of-treatment and follow-up. Further, low evidence was found for small to moderate short-term effect on ADL, lower limb muscle strength and balance.


1996 ◽  
Vol 1996 ◽  
pp. 174-174
Author(s):  
A.M. Sibbald

Voluntary food intake is generally inversely related to body condition or fatness in mature sheep (Foot, 1972). Since the intake of pelleted diets by housed sheep consists of a number of discrete feeding bouts or 'meals' (e.g. Bermudez et al., 1989), the relatively long-term effect of body condition on intake will be achieved through changes in feeding behaviour at the level of a single meal. The aim of this experiment was to compare the effects of body condition and short-term food restriction on meal patterns in sheep, to investigate the mechanism by which body condition influences daily food intake.


1998 ◽  
Vol 25 (6) ◽  
pp. 719 ◽  
Author(s):  
Jie Luo ◽  
Ji-Chu Chen ◽  
Yu-Ju Zhao

Cytokinins can cause de-etiolation of Arabidopsis thaliana (L.) Heynh. seedlings growing in the dark. Brassinosteroids (BRs) have been considered to regulate negatively the de-etiolation in dark-grown Arabidopsis seedlings. We show here that epi-brassinolide (epi-BL) can partially produce the phenotype of de-etiolation as caused by treatment with cytokinins in the dark, including the development of leaves and epicotyls in the wild-type and the BR-deficient mutant det2. But BRs cannot inhibit hypocotyl elongation, nor restore all the inhibition caused by cytokinins and light. We have found that there are distinct short term and long term phases of induction of de-etiolation by cytokinins. The short-term effect is probably coupled to ethylene in the inhibition of the hypocotyl elongation; the long-term effect causes morphogenesis of leaves and epicotyls. BRs can only regulate de-etiolation in the long term. We propose that the inhibition of hypocotyl elongation of det2 in darkness is caused by the absence of BR-dependent elongation rather than the inhibition caused by the expression of genes for photomorphogenesis. We propose that BRs resemble cytokinins in regulating de-etiolation as positive regulators, and that the inhibition of hypocotyl elongation and the development of leaves and epicotyls in de-etiolation are independent processes.


1985 ◽  
Vol 248 (6) ◽  
pp. E706-E711 ◽  
Author(s):  
J. P. van Putten ◽  
H. M. Krans

Catecholamines are known to have short-term regulatory effects on fat cell hexose uptake. We examined the long-term effects of catecholamines on the insulin-sensitive 2-deoxyglucose (dGlc) uptake in cultured 3T3-L1 adipocytes. Prolonged exposure (48 h) to isoproterenol (beta-adrenergic agonist) stimulated the basal dGlc uptake up to 90%. The effect was specific, time, concentration, and protein synthesis dependent and reversible. The effect of insulin was unaltered and superimposed on the increase in basal dGlc uptake. The long-term effect of isoproterenol was mimicked by epinephrine, dibutyryl cAMP (DBcAMP), and 1-methyl-3-isobutylxanthine (IBMX). By contrast, short-term exposure to isoproterenol (and epinephrine) induced a protein synthesis-independent increase in basal dGlc uptake (30%) not accompanied by an increase in insulin responsiveness. Moreover, on short-term basis, DBcAMP and IBMX suppressed both the basal and insulin-stimulated uptake up to 50%. Determination of the intracellular nonphosphorylated dGlc during the uptake and of the hexokinase activity revealed that the long-term effect of isoproterenol was most likely due to alterations low in dGlc transport. In conclusion, long-term regulators of hexose uptake are in cultured 3T3-L1 adipocytes, isoproterenol, and other cAMP stimulators. The long-term effect is independent from the short-term regulatory effect of the agents and from the effect of insulin.


Geoderma ◽  
2020 ◽  
Vol 357 ◽  
pp. 113956 ◽  
Author(s):  
Xiaogang Yin ◽  
Nicolas Beaudoin ◽  
Fabien Ferchaud ◽  
Bruno Mary ◽  
Loïc Strullu ◽  
...  

2004 ◽  
Vol 84 (1) ◽  
pp. 49-61 ◽  
Author(s):  
E. A. Paul ◽  
H. P. Collins ◽  
K. Paustian ◽  
E. T. Elliott ◽  
S. Frey ◽  
...  

Factors controlling soil organic matter (SOM) dynamics in soil C sequestration and N fertility were determined from multi-site analysis of long-term, crop rotation experiments in Western Canada. Analyses included bulk density, organic and inorganic C and N, particulate organic C (POM-C) and N (POM -N), and CO2-C evolved during laboratory incubation. The POM-C and POM-N contents varied with soil type. Differences in POM-C contents between treatments at a site (δPOM-C) were related (r2= 0.68) to treatment differences in soil C (δSOC). The CO2-C, evolved during laboratory incubation, was the most sensitive indicator of management effects. The Gray Luvisol (Breton, AB) cultivated plots had a fivefold difference in CO2-C release relative to a twofold difference in soil organic carbon (SOC). Soils from cropped, Black Chernozems (Melfort and Indian Head, SK) and Dark Brown Chernozems (Lethbridge, AB) released 50 to 60% as much CO2-C as grassland soils. Differences in CO2 evolution from the treatment with the lowest SOM on a site and that of other treatments (δCO2-C) in the early stages of the incubation were correlated to δPOM-C and this pool reflects short-term SOC storage. Management for soil fertility, such as N release, may differ from management for C sequestration. Key words: Multi-site analysis, soil management, soil C and N, POM-C and N, CO2 evolution


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