Effect of straw incorporation on soil N-pool in submerged rice

Empirical relationships between temperature and nitrogen availability across North American forests

Canadian Journal of Forest Research ◽

10.1139/x92-094 ◽

1992 ◽

Vol 22 (5) ◽

pp. 707-712 ◽

Cited By ~ 16

Author(s):

Xiwei Yin

Keyword(s):

N Mineralization ◽

Regional Scale ◽

Mineral Soil ◽

Published Data ◽

N Availability ◽

Net N Mineralization ◽

Soil N ◽

Litter Fall ◽

Available N ◽

N Pool

Published data were analyzed to examine whether nitrogen (N) availability varies along macroclimatic gradients in North America. Extractable N produced during 8-week aerobic laboratory incubation was used as an index of potential net N mineralization. Mean extractable N during the growing season in the forest floor plus top mineral soil was used as an index of the available N pool. Using multiple regression, potential net N mineralization was shown to increase with available N and with litter-fall N (R2 = 0.722). Available N increased with increasing total soil N and with decreasing mean January and July air temperatures (R2 = 0.770). These relationships appeared to hold also for deciduous and coniferous forests separately across regions. Results suggest that net N mineralization output under uniform temperature and moisture conditions can be generally expressed by variations of N input (litter fall) and the available soil N pool, and that the available soil N pool is predictable along a temperature gradient at a regional scale.

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Effects of Changing Temperature on Gross N Transformation Rates in Acidic Subtropical Forest Soils

Forests ◽

10.3390/f10100894 ◽

2019 ◽

Vol 10 (10) ◽

pp. 894

Author(s):

Xiaoqian Dan ◽

Zhaoxiong Chen ◽

Shenyan Dai ◽

Xiaoxiang He ◽

Zucong Cai ◽

...

Keyword(s):

Temperature Change ◽

N Mineralization ◽

Organic N ◽

Mineralization Rate ◽

Soil N ◽

Autotrophic Nitrification ◽

N Transformation ◽

Gross N Transformation ◽

Increasing Temperature ◽

N Pool

Soil temperature change caused by global warming could affect microbial-mediated soil nitrogen (N) transformations. Gross N transformation rates can provide process-based information about abiotic–biotic relationships, but most previous studies have focused on net rates. This study aimed to investigate the responses of gross rates of soil N transformation to temperature change in a subtropical acidic coniferous forest soil. A 15N tracing experiment with a temperature gradient was carried out. The results showed that gross mineralization rate of the labile organic N pool significantly increased with increasing temperature from 5 °C to 45 °C, yet the mineralization rate of the recalcitrant organic N pool showed a smaller response. An exponential response function described well the relationship between the gross rates of total N mineralization and temperature. Compared with N mineralization, the functional relationship between gross NH4+ immobilization and temperature was not so distinct, resulting in an overall significant increase in net N mineralization at higher temperatures. Heterotrophic nitrification rates increased from 5 °C to 25 °C but declined at higher temperatures. By contrast, the rate of autotrophic nitrification was very low, responding only slightly to the range of temperature change in the most temperature treatments, except for that at 35 °C to 45 °C, when autotrophic nitrification rates were found to be significantly increased. Higher rates of NO3− immobilization than gross nitrification rates resulted in negative net nitrification rates that decreased with increasing temperature. Our results suggested that, with higher temperature, the availability of soil N produced from N mineralization would significantly increase, potentially promoting plant growth and stimulating microbial activity, and that the increased NO3− retention capacity may reduce the risk of leaching and denitrification losses in this studied subtropical acidic forest.

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Sources of nitrous oxide from 15N-labelled animal urine and urea fertiliser with and without a nitrification inhibitor, dicyandiamide (DCD)

Soil Research ◽

10.1071/sr07093 ◽

2008 ◽

Vol 46 (1) ◽

pp. 76 ◽

Cited By ~ 41

Author(s):

H. J. Di ◽

K. C. Cameron

Keyword(s):

Nitrous Oxide ◽

Dairy Cow ◽

Priming Effect ◽

Nitrification Inhibitor ◽

Major Effect ◽

N2o Emissions ◽

Soil N ◽

Cow Urine ◽

Nitrification And Denitrification ◽

N Pool

A field lysimeter study was conducted to determine the sources of N2O emitted following the application of dairy cow urine and urea fertiliser labelled with 15N, with and without a nitrification inhibitor, dicyandiamide (DCD). The results show that the application of cow urine at 1000 kg N/ha significantly increased N2O emissions above that from urea applied alone at 25 kg N/ha. The application of urine seemed to have a priming effect, increasing N2O emissions from the soil N pool. Treating the soil with DCD significantly (P < 0.05) decreased N2O emissions from the urine-applied treatment by 72%. The percentage of N2O-N derived from the applied N was 53.1% in the urine-applied treatment and this was reduced to 29.9% when DCD was applied. On average, about 43% of the N2O emitted in the urine-applied treatments was from nitrification. The application of DCD did not have a major effect on the relative contributions of nitrification and denitrification to N2O emissions in the urine treatments. This indicates that the DCD nitrification inhibitor decreased the contributions to N2O emissions from both nitrification and denitrification.

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Contribution of previous year’s leaf N and soil N uptake to current year’s leaf growth in sessile oak

10.5194/bg-2016-59 ◽

2016 ◽

Author(s):

Stephane Bazot ◽

Chantal Fresneau ◽

Claire Damesin ◽

Laure Barthes

Keyword(s):

Leaf Growth ◽

N Uptake ◽

Soil N ◽

Rhizospheric Soil ◽

Growing Seasons ◽

Soil N Uptake ◽

Previous Autumn ◽

Leaf N ◽

N Pool

Abstract. The origin of the N which contributes to the synthesis of N reserves of in situ forest trees in autumn, and to the growth of new organs the following spring, is currently poorly documented. To characterize the metabolism of various possible N sources (plant N and soil N), six distinct 20 year-old sessile oaks were 15N labelled by spraying 15NH415NO3: (i) on leaves in May, to label the N pool remobilized in the autumn for synthesis of reserves; (ii) on soil in the autumn, to label the N pool taken up from soil; (iii) on soil at the beginning of the following spring, to label the N pool taken up from soil in the spring. The partitioning of 15N in leaves, twigs, phloem, xylem, fine roots, rhizospheric soil and microbial biomass was followed during two growing seasons. Results showed a significant incorporation of 15N in the soil-tree system; more than 30 % of the administered 15N was recovered. Analysis of the partitioning clearly revealed that in autumn, roots’ N reserves were formed from foliage 15N (73 %) and to a lesser extent from soil 15N (27 %). The following spring, 15N used for the synthesis of new leaves came first from 15N stored during the previous autumn, mainly from 15N reserves formed from foliage (95 %). Thereafter, when leaves were fully expanded, 15N uptake from soil during the previous autumn and before budburst contributed to the formation of new leaves (60 %).

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Moderate thinning increases soil nitrogen in a Larix principis-rupprechtii (Pinaceae) plantations

10.7287/peerj.preprints.26916v1 ◽

2018 ◽

Cited By ~ 1

Author(s):

Junyong Ma ◽

Hairong Han ◽

Wenwen Zhang ◽

Xiaoqin Cheng

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Management Practice ◽

Light Condition ◽

Stem Density ◽

Soil N ◽

Microbial Biomass Nitrogen ◽

Soil Temperatures ◽

Tree Stem ◽

N Pool

Changes in the concentration of soil N or its components of the soil may directly affect forestry ecosystem functioning. Thinning of forest stands, a widely used forestry management practice, may transform soil nutrients directly by altering the soil environment, or indirectly by changing above- or belowground plant biomass. The study objectives were to determine how tree stem density affects the soil N pool and what mechanisms drive any potential changes. In this study, N and its active components were measured beneath a Larix principis-rupprechtii plantation across two entire growing season and under 12 25*25m plots: LT (low thinning forests, removal of 15% of the trees, three plot repetitions), MT (35% removal) and HT (50% removal) and contrast: CK (no thinning control). The environmental index like the light condition, soil reoperation, soil temperatures and prescription was measured in the plots. Results indicated that STN (soil total nitrogen) was affected by tree stem density adjustments in short-term, STN generally increased with decreasing tree stem density, reaching its highest concentration in the MT treatment before decreasing in HT; this pattern was echoed by DON/STN (DON, dissolve organic nitrogen), under MT, a lower DON/STN was measured across the seasons; and MBN (microbial biomass nitrogen) and the SOC/STN (SOC, soil organic carbon) ratios, density treatments had an influence on MBN concentration and inhibited SOC/STN (SOC, soil organic carbon). MT tended to accumulate more STN and produce lower DON/STN and generally higher microbial activity, which may be partly ascribed to the higher MBN value, MBN/STN ratio and lower DON/STN; and the water condition (water content, surface runoff and sediment loads) and light and soil temperatures may partly be responsible to the N pool dynamic in the different density treatments.

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Modelling the impact of soil processes on the N and O isotope signatures of nitrate in groundwater

10.5194/egusphere-egu21-12432 ◽

2021 ◽

Author(s):

Neus Otero ◽

Mathieu Sebilo ◽

Bernhard Mayer ◽

Daren Gooddy ◽

Dan Lapworth ◽

...

Keyword(s):

Isotopic Composition ◽

Isotope Composition ◽

Organic N ◽

Soil Biology ◽

Soil N ◽

Plant System ◽

Soil Microbial ◽

The Impact ◽

Loire Valley ◽

N Pool

Stable isotope fingerprinting is widely applied to plant-soil-groundwater systems in an aim to identify and even quantify the sources of nitrates found in groundwater. Frequently, in such studies, the &#948;15N and &#948;18O values of nitrogen sources, such as inorganic fertilizers and manure, are directly compared to the isotope signatures of nitrate encountered in groundwater bodies below agricultural watersheds. We submit that the underlying assumptions (conservative behavior of isotope composition, rapid transfer from surface to groundwater) may only be realistic under very specific conditions whereas, in most cases, significant isotope effects exerted by the soil-microbial-plant system on the &#948;15N and &#948;18O values of nitrate need to be taken into account when attempting a quantitative apportionment of sources of groundwater nitrate.We hypothesise that the isotopic signature of nitrate exported from below the root zone and migrating towards the groundwater will reflect the nitrogen isotope composition of the soil organic N pool, rather than the isotope composition of source fertilizer or organic amendments, due to processes that reset source isotope compositions within soil N pools. We test this hypothesis using empirical observations from a diversity of settings, in France, Spain and Canada with a relatively constant historic anthropogenic N source or a simple and well constrained landuse history. Furthermore, through the use of a process-based model (SIMSONIC, Billy et al., 2010) we estimate to what extent the isotopic composition of the predominant N input to the soil-microbial-plant system and the soil N pool has been modified in an attempt to consider these changes in source apportionment studies elucidating the sources of groundwater nitrate.This research was supported through the Consortium award MUTUAL, by the LE STUDIUM&#174; Loire Valley Institute for Advanced Studies via its SMART LOIRE VALLEY (SLV) fellowship programme, co-funded by the H2020 Marie Sklodowska-Curie programme, Contract No. 665790.&#160;Billy C., Billen G., Sebilo M., Birgand F., Tournebize J. (2010) Nitrogen isotopic composition of leached nitrate and soil organic matter as an indicator of denitrification in a sloping drained agricultural plot and adjacent uncultivated riparian buffer strips. Soil Biology and Biochemistry, 42, 108-117.

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Contribution of previous year's leaf N and soil N uptake to current year's leaf growth in sessile oak

Biogeosciences ◽

10.5194/bg-13-3475-2016 ◽

2016 ◽

Vol 13 (11) ◽

pp. 3475-3484 ◽

Cited By ~ 8

Author(s):

Stephane Bazot ◽

Chantal Fresneau ◽

Claire Damesin ◽

Laure Barthes

Keyword(s):

Leaf Growth ◽

N Uptake ◽

Soil N ◽

Rhizospheric Soil ◽

Growing Seasons ◽

Soil N Uptake ◽

Previous Autumn ◽

Leaf N ◽

N Pool

Abstract. The origin of N which contributes to the synthesis of N reserves of in situ forest trees in autumn and to the growth of new organs the following spring is currently poorly documented. To characterize the metabolism of various possible N sources (plant N and soil N), six distinct 20-year-old sessile oaks were 15N labelled by spraying 15NH415NO3: (i) on leaves in May, to label the N pool remobilized in the autumn for synthesis of reserves, (ii) on soil in the autumn, to label the N pool taken up from soil and (iii) on soil at the beginning of the following spring, to label the N pool taken up from soil in the spring. The partitioning of 15N in leaves, twigs, phloem, xylem, fine roots, rhizospheric soil and microbial biomass was followed during two growing seasons. Results showed a significant incorporation of 15N into the soil–tree system; more than 30 % of the administered 15N was recovered. Analysis of the partitioning clearly revealed that in autumn, roots' N reserves were formed from foliage 15N (73 %) and to a lesser extent from soil 15N (27 %). The following spring, 15N used for the synthesis of new leaves came first from 15N stored during the previous autumn, mainly from 15N reserves formed from foliage (95 %). Thereafter, when leaves were fully expanded, 15N uptake from the soil during the previous autumn and before budburst contributed to the formation of new leaves (60 %).

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Fate of biuret 15N and its effect on net mineralisation of native soil N in forest soils

Soil Research ◽

10.1071/sr07208 ◽

2008 ◽

Vol 46 (7) ◽

pp. 636

Author(s):

J. M. Xue ◽

P. W. Clinton ◽

R. Sands ◽

T. W. Payn ◽

M. F. Skinner

Keyword(s):

Organic Matter ◽

Priming Effect ◽

Sandy Loam ◽

Sandy Loam Soil ◽

Silt Loam ◽

Soil N ◽

Native Soil ◽

Loam Soil ◽

Net Mineralisation ◽

N Pool

Biuret (C2H5N3O2) priming effect on mineralisation of native soil N has not been precisely quantified in previous studies, although it is a potential microbial activity regulator and slow-release N fertiliser. Following application of biuret at concentrations of 0 (B0) and 100 (B100) mg/kg (oven-dried) soil, we measured the dynamics of biuret-derived 15N in soil N pools, soil C mineralisation, and microbial biomass C in a sandy loam and a silt loam during a 112-day-long incubation to investigate the fate of biuret 15N and its effect on net mineralisation of native soil N. Biuret was decomposed faster in the sandy loam soil than the silt loam soil. In the sandy loam soil, the stabilised N pool was a strong sink for the biuret-derived 15N and accumulated about half of the applied 15N at the end of incubation. In the silt loam soil, 68% of the 15N applied was recovered in the NO3−-N pool and the stabilised N pool accumulated only about 25% of the applied 15N at the end of incubation. Biuret addition increased the turnover rate constant of soil organic matter and caused a real priming effect on net mineralisation of native soil N in both soils. The additional mineralisation of native soil N was 20.1 mg/kg (equivalent to 27.3 kg N/ha) in the sandy loam soil and 20.5 mg/kg (equivalent to 57.3 kg N/ha) in the silt loam soil. Biuret priming effect was related to the acceleration of soil organic matter decomposition by increased microbial activity at an early stage and the death/decay of microbes at a later stage of incubation. The native soil N released through the priming effect was partially from soil non-biomass organic matter and partially from soil microbial biomass.

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Moderate thinning increases soil nitrogen in a Larix principis-rupprechtii (Pinaceae) plantations

10.7287/peerj.preprints.26916 ◽

2018 ◽

Author(s):

Junyong Ma ◽

Hairong Han ◽

Wenwen Zhang ◽

Xiaoqin Cheng

Keyword(s):

Organic Carbon ◽

Soil Organic Carbon ◽

Management Practice ◽

Light Condition ◽

Stem Density ◽

Soil N ◽

Microbial Biomass Nitrogen ◽

Soil Temperatures ◽

Tree Stem ◽

N Pool

Changes in the concentration of soil N or its components of the soil may directly affect forestry ecosystem functioning. Thinning of forest stands, a widely used forestry management practice, may transform soil nutrients directly by altering the soil environment, or indirectly by changing above- or belowground plant biomass. The study objectives were to determine how tree stem density affects the soil N pool and what mechanisms drive any potential changes. In this study, N and its active components were measured beneath a Larix principis-rupprechtii plantation across two entire growing season and under 12 25*25m plots: LT (low thinning forests, removal of 15% of the trees, three plot repetitions), MT (35% removal) and HT (50% removal) and contrast: CK (no thinning control). The environmental index like the light condition, soil reoperation, soil temperatures and prescription was measured in the plots. Results indicated that STN (soil total nitrogen) was affected by tree stem density adjustments in short-term, STN generally increased with decreasing tree stem density, reaching its highest concentration in the MT treatment before decreasing in HT; this pattern was echoed by DON/STN (DON, dissolve organic nitrogen), under MT, a lower DON/STN was measured across the seasons; and MBN (microbial biomass nitrogen) and the SOC/STN (SOC, soil organic carbon) ratios, density treatments had an influence on MBN concentration and inhibited SOC/STN (SOC, soil organic carbon). MT tended to accumulate more STN and produce lower DON/STN and generally higher microbial activity, which may be partly ascribed to the higher MBN value, MBN/STN ratio and lower DON/STN; and the water condition (water content, surface runoff and sediment loads) and light and soil temperatures may partly be responsible to the N pool dynamic in the different density treatments.

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Water Supply Increases N Acquisition and N Resorption from Old Branches in the Leafless Shrub Calligonum caput-medusae at the Taklimakan Desert Margin

Water ◽

10.3390/w13223288 ◽

2021 ◽

Vol 13 (22) ◽

pp. 3288

Author(s):

Caibian Huang ◽

Fanjiang Zeng ◽

Bo Zhang ◽

Jie Xue ◽

Shaomin Zhang

Keyword(s):

Water Supply ◽

Water Availability ◽

Taklimakan Desert ◽

Soil N ◽

The Taklimakan Desert ◽

Vegetation Establishment ◽

Total Plant ◽

N Resorption ◽

N Use ◽

N Pool

Irrigation is the main strategy deployed to improve vegetation establishment, but the effects of increasing water availability on N use strategies in desert shrub species have received little attention. Pot experiments with drought-tolerant shrub Calligonum caput-medusae supplied with water at five field capacities in the range of 30–85% were conducted using local soil at the southern margin of the Taklimakan Desert. We examined the changes in plant biomass, soil N status, and plant N traits, and addressed the relationships between them in four- and seven-month-old saplings and mature shrubs after 28 months. Results showed that the growth of C. caput-medusae was highly responsive to increased soil moisture supply, and strongly depleted the soil available inorganic N pools from 16.7 mg kg−1 to an average of 1.9 mg kg−1, although the total soil N pool increased in all treatments. Enhancement of biomass production by increasing water supply was closely linked to increasing total plant N pool, N use efficiency (NUE), N resorption efficiency (NRE), and proficiency (NRP) in four-month saplings, but that to total plant N pool, NRE, and NRP after 28 months. The well-watered plants had lower N concentrations in senesced branches compared to their counterparts experiencing the two lowest water inputs. The mature shrubs had higher NRE and NRP than saplings and the world mean levels, suggesting a higher N conservation. Structural equation models showed that NRE was largely controlled by senesced branch N concentrations, and indirectly affected by water supply, whereas NRP was mainly determined by water supply. Our results indicated that increasing water availability increased the total N uptake and N resorption from old branches to satisfy the N requirement of C. caput-medusae. The findings lay important groundwork for vegetation establishment in desert ecosystems.

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