Mulching with pruned fronds promotes the internal soil N cycling and soil fertility in a large-scale oil palm plantation

AbstractIntensive management practices in large-scale oil palm plantations can slow down nutrient cycling and alter other soil functions. Thus, there is a need to reduce management intensity without sacrificing productivity. The aim of our study was to investigate the effect of management practices on gross rates of soil N cycling and soil fertility. In Jambi province, Indonesia, we established a management experiment in a large-scale oil palm plantation to compare conventional practices (i.e. high fertilization rates and herbicide weeding) with reduced management intensity (i.e. reduced fertilization rates and mechanical weeding). Also, we compared the typical management zones characterizing large-scale plantations: palm circle, inter-row and frond-stacked area. After 1.5 years of this experiment, reduced and conventional management showed comparable gross soil N cycling rates; however, there were stark differences among management zones. The frond-stacked area had higher soil N cycling rates and soil fertility (high microbial biomass, extractable C, soil organic C, extractable organic N, total N and low bulk density) than inter-row and palm circle (all p ≤ 0.05). Microbial biomass was the main driver of the soil N cycle, attested by its high correlation with gross N-cycling rates (r = 0.93–0.95, p < 0.01). The correlations of microbial N with extractable C, extractable organic N, soil organic C and total N (r = 0.76–0.89, p < 0.01) suggest that microbial biomass was mainly regulated by the availability of organic matter. Mulching with senesced fronds enhanced soil microbial biomass, which promoted nutrient recycling and thereby can decrease dependency on chemical fertilizers.

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Management of sugarcane harvest residues: consequences for soil carbon and nitrogen

Soil Research ◽

10.1071/sr06080 ◽

2007 ◽

Vol 45 (1) ◽

pp. 13 ◽

Cited By ~ 83

Author(s):

Fiona A. Robertson ◽

Peter J. Thorburn

Keyword(s):

Microbial Biomass ◽

Soil Fertility ◽

Microbial Activity ◽

Soil N ◽

Soil Organic C ◽

Total N ◽

Organic C ◽

Soil Microbial ◽

C And N

The Australian sugar industry is moving away from the practice of burning the crop before harvest to a system of green cane trash blanketing (GCTB). Since the residues that would have been lost in the fire are returned to the soil, nutrients and organic matter may be accumulating under trash blanketing. There is a need to know if this is the case, to better manage fertiliser inputs and maintain soil fertility. The objective of this work was to determine whether conversion from a burning to a GCTB trash management system is likely to affect soil fertility in terms of C and N. Indicators of short- and long-term soil C and N cycling were measured in 5 field experiments in contrasting climatic conditions. The effects of GCTB varied among experiments. Experiments that had been running for 1–2 years (Harwood) showed no significant trash management effects. In experiments that had been running for 3–6 years (Mackay and Tully), soil organic C and total N were up to 21% greater under trash blanketing than under burning, to 0.10 or 0.25 m depth (most of this effect being in the top 50 mm). Soil microbial activity (CO2 production) and soil microbial biomass also increased under GCTB, presumably as a consequence of the improved C availability. Most of the trash C was respired by the microbial biomass and lost from the system as CO2. The stimulation of microbial activity in these relatively short-term GCTB systems was not accompanied by increased net mineralisation of soil N, probably because of the greatly increased net immobilisation of N. It was calculated that, with standard fertiliser applications, the entire trash blanket could be decomposed without compromising the supply of N to the crop. Calculations of possible long-term effects of converting from a burnt to a GCTB production system suggested that, at the sites studied, soil organic C could increase by 8–15%, total soil N could increase by 9–24%, and inorganic soil N could increase by 37 kg/ha.year, and that it would take 20–30 years for the soils to approach this new equilibrium. The results suggest that fertiliser N application should not be reduced in the first 6 years after adoption of GCTB, but small reductions may be possible in the longer term (>15 years).

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Introduction of Dalbergia odorifera enhances nitrogen absorption on Eucalyptus through stimulating microbially mediated soil nitrogen-cycling

Forest Ecosystems ◽

10.1186/s40663-021-00339-3 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Xianyu Yao ◽

Qianchun Zhang ◽

Haiju Zhou ◽

Zhi Nong ◽

Shaoming Ye ◽

...

Keyword(s):

Microbial Biomass ◽

Soil Ph ◽

N Cycling ◽

N Availability ◽

Soil N ◽

Total N ◽

Available N ◽

Soil C ◽

Hot Season ◽

Dalbergia Odorifera

Abstract Background There is substantial evidence that Eucalyptus for nitrogen (N) absorption and increasing the growth benefit from the introduction of N-fixing species, but the underlying mechanisms for microbially mediated soil N cycling remains unclear. Methods We investigated the changes of soil pH, soil water content (SWC), soil organic carbon (SOC), total N (TN), inorganic N (NH4+-N and NO3−-N), microbial biomass and three N-degrading enzyme activities as well as the biomass and N productivity of Eucalyptus between a pure Eucalyptus urophylla × grandis plantation (PP) and a mixed Dalbergia odorifera and Eucalyptus plantation (MP) in Guangxi Zhuang Autonomous Region, China. Results Compared with the PP site, soil pH, SWC, SOC and TN in both seasons were significantly higher at the MP site, which in turn enhanced microbial biomass and the activities of soil N-degrading enzymes. The stimulated microbial activity at the MP site likely accelerate soil N mineralization, providing more available N (NH4+-N in both seasons and NO3−-N in the wet-hot season) for Eucalyptus absorption. Overall, the N productivity of Eucalyptus at the MP site was increased by 19.7% and 21.9%, promoting the biomass increases of 15.1% and 19.2% in the dry-cold season and wet-hot season, respectively. Conclusion Our results reveal the importance of microbially mediated soil N cycling in the N absorption on Eucalyptus. Introduction of D. odorifera enhances Eucalyptus biomass and N productivity, improve soil N availability and increased soil C and N concentration, which hence can be considered to be an effective sustainable management option of Eucalyptus plantations.

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Linkages between soil carbon, soil fertility and nitrogen fixation in Acacia senegal plantations of varying age in Sudan

PeerJ ◽

10.7717/peerj.5232 ◽

2018 ◽

Vol 6 ◽

pp. e5232 ◽

Cited By ~ 1

Author(s):

Wafa E. Abaker ◽

Frank Berninger ◽

Gustavo Saiz ◽

Jukka Pumpanen ◽

Mike Starr

Keyword(s):

Soil Fertility ◽

Management Practices ◽

Sub Saharan Africa ◽

Mineral Nutrient ◽

Nutrient Concentrations ◽

Soil N ◽

Acacia Senegal ◽

Total N ◽

C:N:P Stoichiometry ◽

Sahel Region

Background Over the last decades sub-Saharan Africa has experienced severe land degradation and food security challenges linked to loss of soil fertility and soil organic matter (SOM), recurrent drought and increasing population. Although primary production in drylands is strictly limited by water availability, nutrient deficiencies, particularly of nitrogen (N) and phosphorus (P), are also considered limiting factors for plant growth. It is known that SOM (often measured as soil organic carbon (SOC)) is a key indicator of soil fertility, therefore, management practices that increase SOM contents, such as increasing tree cover, can be expected to improve soil fertility. The objectives of this study were to investigate the effect of Acacia senegal (Senegalia senegal) trees on soil nitrogen, phosphorus and potassium (K) in relation to SOC, the potential of A. senegal for N2 fixation, and to identify possible N and P ecosystem limitations. Methods Soil nutrient (total N, P, K and available P and exchangeable K) concentrations and stocks were determined for the 0–10, 10–20,20–30 and 30–50 cm layers of A. senegal plantations of varying age (ranging from 7 to 24-years-old) and adjacent grasslands (reference) at two sites in semi-arid areas of Sudan. At both sites, three plots were established in each grassland and plantation. The potential of A. senegal for N2 fixation in relation to plantations age was assessed using δ15N isotopic abundances and nutrient limitations assessed using C:N:P stoichiometry. Results Soil concentrations of all studied nutrients were relatively low but were significantly and directly correlated to SOC concentrations. SOC and nutrient concentrations were the highest in the topsoil (0–10 cm) and increased with plantations age. Acacia foliage δ15N values were >6‰ and varied little with plantations age. Soil C:N and C:P ratios did not differ between grassland and plantations and only 0–10 cm layer N:P ratios showed significant differences between grassland and plantations. Discussion The results indicated that soil fertility in the Sahel region is strongly related to SOM contents and therefore highlighting the importance of trees in the landscape. The higher mineral nutrient concentrations in the topsoil of the plantations may be an indication of ‘nutrient uplift’ by the deeper roots. The high foliar δ15N values indicated that N2 fixation was not an important contributor to soil N contents in the plantations. The accretion of soil N cannot be explained by deposition but may be related to inputs of excreted N brought into the area annually by grazing and browsing animals. The soil C:N:P stoichiometry indicated that the plantations may be limited by P and the grasslands limited by N.

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Introduction of Dalbergia Odorifera Enhances Nitrogen Absorption on Eucalyputs Through Stimulating Microbially Mediated Soil Nitrogen-cycling

10.21203/rs.3.rs-683628/v1 ◽

2021 ◽

Author(s):

Xianyu Yao ◽

Qianchun Zhang ◽

Haiju Zhou ◽

Zhi Nong ◽

Shaoming Ye ◽

...

Keyword(s):

Microbial Biomass ◽

Soil Ph ◽

N Cycling ◽

N Availability ◽

Soil N ◽

N Accumulation ◽

Total N ◽

Available N ◽

Hot Season ◽

Dalbergia Odorifera

Abstract Background: There is the substantial evidence that Eucalyptus for nitrogen (N) absorption and increasing the growth benefit from the introduction of N-fixing species, but the underlying mechanisms for microbially mediated soil N cycling remains unclear. Methods: We investigated the changes of soil pH, soil water content (SWC), soil organic carbon (SOC), total N (TN), inorganic N (NH4+-N and NO3--N), microbial biomass and three N-degrading enzyme activities as well as the biomass and N accumulation of Eucalyptus between a pure Eucalyptus urophylla × grandis plantation (PP) and a mixed Dalbergia odorifera and Eucalyptus plantation (MP) in Guangxi Zhuang Autonomous Region, China. Results: Compared with the PP site, soil pH, SWC, SOC and TN in both seasons were significantly higher at the MP site, which in turn enhanced microbial biomass and the activities of soil N-degrading enzymes. The stimulated microbial activity at the MP site likely accelerated soil N mineralization, providing more available N (NH4+-N in both seasons and NO3--N in the wet-hot season) for Eucalyptus absorption. Overall, the N accumulation of Eucalyptus at the MP site was increased by 19.7% and 21.9%, promoting the biomass increases of 15.1% and 19.2% in the dry-cold season and wet-hot season, respectively.Conclusion: Our results reveal the importance of microbially mediated soil N cycling in the N absorption on Eucalyputs. Introduction of D. odorifera can enhance N absorption and growth on Eucalyputs, improve soil N availability and increased soil C sequestration, which hence can be considered to be an effective sustainable management option of Eucalyptus plantations.

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Compound-specific <sup>15</sup>N stable isotope probing of N assimilation by the soil microbial biomass: a new methodological paradigm in soil N cycling

SOIL Discussions ◽

10.5194/soild-2-1135-2015 ◽

2015 ◽

Vol 2 (2) ◽

pp. 1135-1160

Author(s):

A. F. Charteris ◽

T. D. J. Knowles ◽

K. Michaelides ◽

R. P. Evershed

Keyword(s):

Stable Isotope ◽

Microbial Biomass ◽

Soil Microbial Biomass ◽

Stable Isotope Probing ◽

N Cycling ◽

Organic N ◽

Soil N ◽

Soil Microbial ◽

Incubation Experiments ◽

N Assimilation

Abstract. A compound-specific nitrogen-15 stable isotope probing (15N-SIP) technique is described which allows investigation of the fate of inorganic- or organic-N amendments to soils. The technique uses gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) to determine the δ15N values of individual amino acids (AAs; determined as N-acetyl, O-isopropyl derivatives) as proxies of biomass protein production. The δ15N values are used together with AA concentrations to quantify N assimilation of 15N-labelled substrates by the soil microbial biomass. The utility of the approach is demonstrated through incubation experiments using inorganic 15N-labelled substrates ammonium (15NH4+) and nitrate (15NO3-) and an organic 15N-labelled substrate, glutamic acid (15N-Glu). Assimilation of all the applied substrates was undetectable based on bulk soil properties, i.e. % total N (% TN), bulk soil N isotope composition and AA concentrations, all of which remained relatively constant throughout the incubation experiments. In contrast, compound-specific AA δ15N values were highly sensitive to N assimilation, providing qualitative and quantitative insights into the cycling and fate of the applied 15N-labelled substrates. The utility of this 15N-AA-SIP technique is considered in relation to other currently available methods for investigating the microbially-mediated assimilation of nitrogenous substrates into the soil organic N pool. This approach will be generally applicable to the study of N cycling in any soil, or indeed, in any complex ecosystem.

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Integrated Nutrient Management for Potato-Maize-T. Aman Rice Cropping Pattern

Bangladesh Rice Journal ◽

10.3329/brj.v20i1.30629 ◽

2016 ◽

Vol 20 (1) ◽

pp. 51-58

Author(s):

PK Saha ◽

F Rahman ◽

M Akter ◽

R Islam ◽

ATMS Hossain ◽

...

Keyword(s):

Soil Fertility ◽

Management Practices ◽

Nutrient Management ◽

Poultry Manure ◽

Chemical Fertilizer ◽

Cropping Pattern ◽

Integrated Nutrient Management ◽

Total N ◽

Organic C ◽

Nutrient Sources

A field experiment on integrated nutrient management (INM) for Potato-Maize-T. Aman cropping pattern was conducted at BRRI RS farm, Rangpur (AEZ-3) during 2007-2010. The objectives were to examine the effect of Potato-Maize-T. Aman cropping on soil fertility and to develop appropriate fertilizer management practices for the above mentioned pattern. Inorganic and organic nutrient sources were tested in six different combinations in Rangpur region. Poultry manure (PM) @ 3.0 t ha-1 + IPNS based inorganic fertilizers for potato (N80, P0, K30, S0, Zn0, Mg4, B1) and maize (N136, P0, K40, S2, Zn1.8, Mg2, B1) crops, and STB dose for T. Aman crop (N65, P3, K27, S8) has been recommended for Potato-Maize-T. Aman cropping pattern in Rangpur region. In fertilized plots, there was an apparent negative balance for N and K. The balances for P and S were positive. Organic C, total N and available P in soil increased due to integration of chemical fertilizer with PM. Results indicate that it is necessary to apply organic manure in combination with chemical fertilizer for sustaining soil fertility. For maize and potato crops, fertilizer dose needs to be updated after every three years of successive crop cultivation under Potato-Maize-T. Aman cropping pattern. Net additional income was the highest in T5 where PM and IPNS based fertilizer applied.Bangladesh Rice j. 2016, 20(1): 51-58

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BIOLOGICAL PROPERTIES OF SOME PRINCE EDWARD ISLAND SOILS: RELATIONSHIP BETWEEN MICROBIAL BIOMASS NITROGEN AND MINERALIZABLE NITROGEN

Canadian Journal of Soil Science ◽

10.4141/cjss87-029 ◽

1987 ◽

Vol 67 (2) ◽

pp. 333-340 ◽

Cited By ~ 31

Author(s):

M. R. CARTER ◽

J. A. MACLEOD

Keyword(s):

Microbial Biomass ◽

N Mineralization ◽

Prince Edward Island ◽

Organic N ◽

Microbial Biomass N ◽

Soil N ◽

Mineral N ◽

Organic C ◽

Mineralization Potential ◽

N Mineralization Potential

The mineral N flush, a measure of microbial biomass N, and the N mineralization potential (No) were determined in eight representative agricultural soils (Humo-Ferric Podzols and Gray Luvisols) of Prince Edward Island. The acidic (pH 5.0–5.8) soils, varying in texture from loam to loamy sand had an organic C range of 0.75–2.74%. Both mineral N flush (4–38 μg N g−1 soil) and the percentage soil organic N in the mineral N flush (0.4–2.0%) were relatively low compared to other studies. This observation was related to the generally low pH range of these soils. Potentially mineralizable soil N (No) ranged from 44 to 247 μg N g−1 and accounted for 4.5–13.3% of the total soil organic N. The No was closely related to the mineral N flush (r2 = 0.94) but poorly related to percent organic matter (r2 = 0.26) or organic N (r2 = 0.38). The results indicate that for these soils of similar properties, with low levels of residual mineral N, the mineral N flush could be utilized as an indirect measure of the soil N mineralization potential. Key words: Biomass C, mineral N flush, N mineralization potential, Podzolic soil, Luvisolic soil

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Effects of two wood-based biochars on the fate of added fertilizer nitrogen—a 15N tracing study

Biology and Fertility of Soils ◽

10.1007/s00374-020-01534-0 ◽

2021 ◽

Author(s):

Subin Kalu ◽

Gboyega Nathaniel Oyekoya ◽

Per Ambus ◽

Priit Tammeorg ◽

Asko Simojoki ◽

...

Keyword(s):

Plant Uptake ◽

Plant Biomass ◽

Application Rate ◽

Control Treatment ◽

Organic N ◽

N Leaching ◽

Soil N ◽

Mineral N ◽

Total N ◽

Application Rates

AbstractA 15N tracing pot experiment was conducted using two types of wood-based biochars: a regular biochar and a Kon-Tiki-produced nutrient-enriched biochar, at two application rates (1% and 5% (w/w)), in addition to a fertilizer only and a control treatment. Ryegrass was sown in pots, all of which except controls received 15N-labelled fertilizer as either 15NH4NO3 or NH415NO3. We quantified the effect of biochar application on soil N2O emissions, as well as the fate of fertilizer-derived ammonium (NH4+) and nitrate (NO3−) in terms of their leaching from the soil, uptake into plant biomass, and recovery in the soil. We found that application of biochars reduced soil mineral N leaching and N2O emissions. Similarly, the higher biochar application rate of 5% significantly increased aboveground ryegrass biomass yield. However, no differences in N2O emissions and ryegrass biomass yields were observed between regular and nutrient-enriched biochar treatments, although mineral N leaching tended to be lower in the nutrient-enriched biochar treatment than in the regular biochar treatment. The 15N analysis revealed that biochar application increased the plant uptake of added nitrate, but reduced the plant uptake of added ammonium compared to the fertilizer only treatment. Thus, the uptake of total N derived from added NH4NO3 fertilizer was not affected by the biochar addition, and cannot explain the increase in plant biomass in biochar treatments. Instead, the increased plant biomass at the higher biochar application rate was attributed to the enhanced uptake of N derived from soil. This suggests that the interactions between biochar and native soil organic N may be important determinants of the availability of soil N to plant growth.

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Effect of Soil Management on Erosion in Mountain Vineyards (N-W Italy)

Sustainability ◽

10.3390/su13041991 ◽

2021 ◽

Vol 13 (4) ◽

pp. 1991

Author(s):

Silvia Stanchi ◽

Odoardo Zecca ◽

Csilla Hudek ◽

Emanuele Pintaldi ◽

Davide Viglietti ◽

...

Keyword(s):

Soil Erosion ◽

Management Practices ◽

Soil Management ◽

Buffer Strips ◽

Total N ◽

Organic C ◽

Erosion Rates ◽

Soil Ecosystem Services ◽

Erosion Mitigation ◽

Management Approaches

We studied the effects of three soil management approaches (permanent grassing, chemical weeding, and buffer strips), and the additional impact of tractor passage on soil erosion in a sloping vineyard located in the inner part of Aosta Valley (N-W Italian Alps). The vineyard rows were equipped with a sediment collection system with channels and barrel tanks. A total of 12 events with sediment production were observed across 6 years, and the collected sediments were weighted and analyzed. Average erosion rates ranged from negligible (mainly in grassed rows) to 1.1 t ha−1 per event (after weeding). The most erosive event occurred in July 2015, with a total rainfall of 32.2 mm, of which 20.1 were recorded in 1 h. Despite the limited number of erosive events observed, and the low measured erosion rates, permanent grassing reduced soil erosion considerably with respect to weeding; buffering had a comparable effect to grassing. The tractor passage, independent of the soil management approaches adopted, visibly accelerated the erosion process. The collected sediments were highly enriched in organic C, total N, and fine size fractions, indicating a potential loss of fertility over time. Despite the measured erosion rates being low over the experiment’s duration, more severe events are well documented in the recent past, and the number of intense storms is likely to increase due to climate change. Thus, the potential effects of erosion in the medium and long term need to be limited to a minimum rate of soil loss. Our experiment helped to compare soil losses by erosion under different soil management practices, including permanent grassing, i.e., a nature-based erosion mitigation measure. The results of the research can provide useful indications for planners and practitioners in similar regions, for sustainable, cross-sectoral soil management, and the enhancement of soil ecosystem services.

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Soil Chemistry and Cucumber (Cucumis sativus L.) Yield as Influenced by 16 Years of Composted Poultry Litter Addition

Journal of Agricultural Science ◽

10.5539/jas.v10n1p325 ◽

2017 ◽

Vol 10 (1) ◽

pp. 325

Author(s):

Hebert D. A. Abobi ◽

Armand W. Koné ◽

Bernard Y. Koffi ◽

Saint Salomon F. Diahuissié ◽

Stanislas K. Loukou ◽

...

Keyword(s):

Soil Fertility ◽

Growth Parameters ◽

Block Design ◽

C:N Ratio ◽

Poultry Litter ◽

Growth And Yield ◽

Soil Parameters ◽

Total N ◽

Organic C ◽

Litter Addition

Poultry litter is increasingly used as organic amendment in market gardening in Côte d’Ivoire. To know about the sustainability of this practice, its impacts on soil quality should be known. This study aimed at assessing the effect on soil fertility of composted poultry litter addition for 16 years following two distinct ways, and identifying soil parameters driving cucumber yield. Trials were laid out in a Fisher randomized block design with 3 treatments replicated 5 times each: Control (C), Surface-applied compost (SAC) and Buried compost (BC). Soil (0-20 cm) chemical characteristics and cucumber growth and yield parameters were measured. Values of all parameters were higher with compost addition compared to the control, except for the C:N ratio. SAC and BC showed similar values of organic C, total N, CEC, pH and available phosphorus. However, Ca2+, Mg2+, K+ and base saturation were higher in SAC than in BC. Relative to values in the control, the greatest changes in soil parameters were observed with exchangeable cations, followed by soil organic matter. Soil organic C and total N concentrations have doubled in SAC while Ca2+, Mg2+, and K+ increased at greater rate (702.4, 400.9 and 186.67% respectively). Also, cucumber growth parameters were the highest with compost addition compared to the control. Significant effect of the compost application way on cucumber was also observed: collar diameter, leaf area and fresh fruit yield in SAC (0.72±0.02 cm, 258.9±12.3 cm2, 11.1±1.3 t ha-1, respectively) were higher than in BC (0.56±0.01 cm, 230.2±2.5 cm2, 5.4±0.5 t ha-1 respectively). Fruit yields in SAC and BC were four times and twice higher than in the control (2.6±0.3 t ha-1), respectively. Cucumber growth parameters were determined by soil concentration in Mg2+ while yield was determined by Ca2+. Composted poultry litter should be promoted for a sustainable soil fertility management in vegetable farming systems.

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