Nitrogen mineralization in short-rotation tree plantations along a soil nitrogen gradient

2006 ◽  
Vol 36 (5) ◽  
pp. 1236-1242 ◽  
Author(s):  
Kye-Han Lee ◽  
Shibu Jose

We measured soil nitrogen (N) mineralization along an N fertilization gradient (control; irrigation only (I + 0 N); irrigation with 56 (I + 56 N), 112 (I + 112 N), and 224 (I + 224 N) kg N·ha–1·year–1, respectively) in 7-year-old cottonwood (Populus deltoides Marsh.), cherrybark oak (Quercus falcata Michx. var. pagodifolia Ell.), American sycamore (Platanus occidentalis L.), and loblolly pine (Pinus taeda L.) plantations established on a well-drained Redbay sandy loam (a fine loamy, siliceous, thermic Rhodic Paleudult), in Florida, USA. Nitrogen mineralization was measured monthly for 1 year, beginning in April 2001, with the buried bag incubation technique. Irrigation alone or fertigation (irrigation + N) affected annual net N mineralization rates under hardwood species, but no effect was found under loblolly pine. Overall, the rates were higher under cherrybark oak (108 kg N·ha–1·year–1) and cottonwood (101 kg N·ha–1·year–1) than under sycamore (82 kg N·ha–1·year–1) and loblolly pine (75 kg N·ha–1·year–1). Significant correlations were observed between N mineralization and stem volume in all species but loblolly pine. These results suggest that N mineralization response to irrigation or fertigation (irrigation + N) is heavily dependent on species-specific feedback mechanisms. Our results also support the hypothesis that the N mineralization versus productivity relationship is a fundamental feature of forests, resulting from the impact of N availability on productivity and the long-term feedback effects of vegetation on N availability.

Agronomy ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 444 ◽  
Author(s):  
Chen-Chi Tsai ◽  
Yu-Fang Chang

Adding biochar to excessive compost amendments may affect compost mineralization rate and nitrogen (N) availability. The objective of this 371-day incubation study was to evaluate the effects of four proportions of woody biochar (0%, 0.5%, 1.0%, and 2.0%) from lead tree (Leucaena leucocephala (Lam.) de. Wit) biochar produced at 750 °C through dynamic mineral N and N mineralization rates in three rural soils (one Oxisol and two Inceptisols). In each treatment, 5% poultry–livestock manure compost was added to serve as an excessive application. The results indicated that the biochar decreased available total inorganic nitrogen (TIN) (NO3−-N+NH4+-N) by on average 6%, 9% and 19% for 0.5%, 1.0% and 2.0% treatments, respectively. The soil type strongly influenced the impact of the biochar addition on the soil nitrogen mineralization potential, especially the soil pH and clay content. This study showed that the co-application of biochar and excessive compost benefited the agricultural soils by improving NO3−-N retention in agroecosystems. The application of biochar to these soils to combine it with excessive compost appeared to be an effective method of utilizing these soil amendments, as it diminished the net N mineralization potential and reduced the nitrate loss of the excessive added compost.


2020 ◽  
Vol 18 (1) ◽  
pp. e1101
Author(s):  
Miguel Oliveira ◽  
Dragan Rebac ◽  
João Coutinho ◽  
Luís Ferreira ◽  
Henrique Trindade

Aim of study: To assess the interactive effects of legume species, residue placement and temperature on the net nitrogen (N) mineralization dynamics in a sandy loam soil.Area of study: Northern PortugalMaterial and methods: Cowpea (Vigna unguiculata L. Walp), faba bean (Vicia faba L.) and pea (Pisum sativum L.) residues were incorporated or applied to the soil surface at typical field yields in Europe and incubated in aerobic conditions for up to 240 days, either at 10ºC or 20ºC. Initial chemical characteristics of the soil and residues were determined. Net N mineralization was estimated at eight time intervals.Main results: Cowpea residues caused no negative changes in soil mineral N contents and were able to release the equivalent of 21-45 kg N ha-1 in 240 days. Net N immobilization (up to 17 kg N ha-1) was observed throughout most of the trial in soil with faba bean and pea residues. Differences in mineralization patterns could be attributed to the higher quality (lower carbon to nitrogen (C:N) ratios) of cowpea. Surface placement increased net N mineralized by as much as 18 kg N ha-1. The sensitivity of N mineralization to changes in temperature and residue placement varied with legume species, likely due to effects associated with differences in C:N ratios.Research highlights: Adding cowpea residues to soil is suitable when high N availability is immediately required. Faba bean or pea residues are better suited for conservation of soil N for later release.


1989 ◽  
Vol 19 (6) ◽  
pp. 816-820 ◽  
Author(s):  
Randy L. Bell ◽  
Dan Binkley

Additions of 15N-labelled ammonium sulfate were used to evaluate the effects of burning at 2- and 4-year intervals during a 24-year period on nitrogen mineralization and immobilization in a loblolly pine (Pinustaeda L.) stand. Net N mineralization in 10-day laboratory incubations of Oe + Oa plus 0–10 cm mineral soil was greatest in the control (210 mg N/m2), intermediate for the 2 year interval burn treatment (87 mg N/m2), and lowest for the 4 year interval burn treatment (78 mg N/m2). Forest floor and mineral soil C/N ratios were greater for the burn treatments than for the control. All samples showed >95% immobilization of added 15N ammonium sulfate, the pattern being 2-year interval >4-year interval control. Both burning regimes appeared to increase N immobilization and decrease N availability on this very N-poor site.


2000 ◽  
Vol 80 (2) ◽  
pp. 271-276 ◽  
Author(s):  
T. Paré ◽  
H. Dinel ◽  
M. Schnitzer

The recycling of poultry (Gallus gallus domesticus) manure (PM) needs to be done in a manner that will not only improve soil physical, chemical and biological properties but also minimize environmental risks. Untreated PM is more difficult to handle and more expensive to apply than granular fertilizers; the application of PM in the form of tablets may be a suitable alternative. It is necessary to determine whether C and N mineralization in tabletized PM (T-PM) differs from non-tabletized PM (NT-PM). Net C and N mineralization from a Brandon loam soil (Typic Endoaquoll) amended with NT-PM and T-PM, were measured in an incubation study at 25 °C. After 60 d of incubation, about 62 and 77% of total PM carbon was mineralized in NT-PM and T-PM amended soils, respectively. Carbon mineralization was not stimulated by the addition of PM tablets containing NPK to soil, while in soils mixed with NT-PM + NPK, soil respiration was reduced. Net N mineralization was similar in soils amended with T-PM and NT-PM, although changes in ammonium (NH4+–N) concentrations during incubation differed. Generally more NH4+–N accumulated in soil amended with T-PM and T-PM + NPK than with NT-PM and NT-PM + NPK The concentrations of nitrate (NO3−–N) did not differ in soils amended with T-PM and NT-PM, indicating a reduction in nitrification and NH4+–N accumulation in soils amended with PM tablets. Key words: Poultry manure, tablets, carbon mineralization, nitrogen mineralization, organic fertilizer


2014 ◽  
Vol 6 (2) ◽  
pp. 3051-3074 ◽  
Author(s):  
M. K. Abbasi ◽  
M. M. Tahir ◽  
N. Sabir ◽  
M. Khurshid

Abstract. Application of plant residues as soil amendment may represent a valuable recycling strategy that affects on carbon (C) and nitrogen (N) cycling, soil properties improvement and plant growth promotion. The amount and rate of nutrient release from plant residues depend on their quality characteristics and biochemical composition. A laboratory incubation experiment was conducted for 120 days under controlled conditions (25 °C and 58% water filled pore space (WFPS)) to quantify initial biochemical composition and N mineralization of leguminous and non-leguminous plant residues i.e. the roots, shoots and leaves of Glycine max, Trifolium repens, Zea mays, Poplus euramericana, Rubinia pseudoacacia and Elagnus umbellate incorporated into the soil at the rate of 200 mg residue N kg−1 soil. The diverse plant residues showed wide variation in total N, carbon, lignin, polyphenols and C/N ratio with higher polyphenol content in the leaves and higher lignin content in the roots. The shoot of G. max and the shoot and root of T. repens displayed continuous mineralization by releasing a maximum of 109.8, 74.8 and 72.5 mg N kg−1 and representing a 55, 37 and 36% of added N being released from these resources. The roots of G. max and Z. mays and the shoot of Z. mays showed continuous negative values throughout the incubation showing net immobilization. After an initial immobilization, leaves of P. euramericana, R. pseudoacacia and E. umbellate exhibited net mineralization by releasing a maximum of 31.8, 63.1 and 65.1 mg N kg−1, respectively and representing a 16, 32 and 33% of added N being released. Nitrogen mineralization from all the treatments was positively correlated with the initial residue N contents (r = 0.89; p ≤ 0.01), and negatively correlated with lignin content (r = −0.84; p ≤ 0.01), C/N ratio (r = −0.69; p ≤ 0.05), lignin/N ratio (r = −0.68; p ≤ 0.05), polyphenol/N ratio (r = −0.73; p ≤ 0.05) and ligin + polyphenol/N ratio (r = −0.70; p ≤ 0.05) indicating a significant role of residue chemical composition and quality in regulating N transformations and cycling in soil. The present study indicates that incorporation of plant residues strongly modify the mineralization-immobilization turnover (MIT) of soil that can be taken into account to develop synchronization between net N mineralization and crop demand in order to maximize N delivery and minimize N losses.


1992 ◽  
Vol 22 (5) ◽  
pp. 707-712 ◽  
Author(s):  
Xiwei Yin

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.


2016 ◽  
Vol 13 (18) ◽  
pp. 5395-5403 ◽  
Author(s):  
Maya Almaraz ◽  
Stephen Porder

Abstract. There are many proxies used to measure nitrogen (N) availability in watersheds, but the degree to which they do (or do not) correlate within a watershed has not been systematically addressed. We surveyed the literature for intact forest or grassland watersheds globally, in which several metrics of nitrogen availability have been measured. Our metrics included the following: foliar δ15N, soil δ15N, net nitrification, net N mineralization, and the ratio of dissolved inorganic to organic nitrogen (DIN : DON) in soil solution and streams. We were particularly interested in whether terrestrial and stream based proxies for N availability were correlated where they were measured in the same place. Not surprisingly, the strongest correlation (Kendall's τ) was between net nitrification and N mineralization (τ  =  0.71, p < 0.0001). Net nitrification and N mineralization were each correlated with foliar and soil δ15N (p < 0.05). Foliar and soil δ15N were more tightly correlated in tropical sites (τ  =  0.68, p < 0.0001), than in temperate sites (τ  =  0.23, p  =  0.02). The only significant correlations between terrestrial- and water-based metrics were those of net nitrification (τ  =  0.48, p  =  0.01) and N mineralization (τ  =  0.69, p  =  0.0001) with stream DIN : DON. The relationship between stream DIN : DON with both net nitrification and N mineralization was significant only in temperate, but not tropical regions. To our surprise, we did not find a significant correlation between soil δ15N and stream DIN : DON, despite the fact that both have been used to infer spatially or temporally integrated N status. Given that both soil δ15N and stream DIN : DON are used to infer long-term N status, their lack of correlation in watersheds merits further investigation.


2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Rodrick D. Lentz ◽  
Gary A. Lehrsch

The use of solid dairy manure for sugarbeet production is problematic because beet yield and quality are sensitive to deficiencies or excesses in soil N, and soil N availability from manure varies substantially depending on the year of application. Experimental treatments included combinations of two manure rates (0.33 and 0.97 Mg total N ha−1) and three application times, and non-manure treatments (control and urea fertilizer). We measured soil net N mineralization and biomass, N uptake, and yields for sprinkler-irrigated sugarbeet. On average, the 1-year-old, low-rate manure, and 1- and 2-year-old, high-rate manure treatments produced 1.2-fold greater yields, 1.1-fold greater estimated recoverable sugar, and 1.5-fold greater gross margins than that of fertilizer alone. As a group the 1-year-old, low-rate manure, and 2- and 3-year-old, high-rate-manure treatments produced similar cumulative net N mineralization as urea fertilizer; whereas the 1-year-old, high-rate manure treatment provided nearly 1.5-fold more N than either group. With appropriate manure application rates and attention to residual N and timing of sugarbeet planting, growers can best exploit the N mineralized from manure, while simultaneously maximizing sugar yields and profits.


2000 ◽  
Vol 30 (9) ◽  
pp. 1341-1352 ◽  
Author(s):  
C E Prescott ◽  
L Vesterdal ◽  
J Pratt ◽  
K H Venner ◽  
L M de Montigny ◽  
...  

We examined the extent to which nutrient concentrations and C and N mineralization rates in forests floors under different tree species are predictable from the chemistry of foliar litter and its rate of decomposition. We studied replicated single species plantations of western redcedar (Thuja plicata Donn ex D. Don), western hemlock (Tsuga heterophylla (Raf.) Sarg.), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), and Sitka spruce (Picea sitchensis (Bong.) Carr.) at four locations. Nutrient concentrations in forest floors correlated poorly with litter nutrient concentrations; the only significant relationships were for Ca and K. Nitrogen mineralization correlated weakly with forest floor C/N ratio, and differed more among sites than among species. None of the litter chemistry parameters were related to net N mineralization rates. Decomposition was fastest in hemlock litter, intermediate in Douglas-fir litter and lowest in cedar litter. Litter also decomposed more rapidly on hemlock forest floors than on cedar forest floors. Rates of N mineralization in the forest floors were not related to rates of decomposition of foliar litter. Differences among sites in N mineralization rates were related to the understory vegetation composition, particularly the amount of the ericaceous shrub salal, which in turn was related to slope position. These site factors appeared to override the effect of tree species on rates of N mineralization.


1994 ◽  
Vol 24 (8) ◽  
pp. 1636-1645 ◽  
Author(s):  
Charles T. Garten Jr. ◽  
Helga Van Miegroet

We tested the hypothesis that naturally occurring nitrogen (N) isotope ratios in foliage (from plants that do not symbiotically fix atmospheric N2) are an indicator of soil N dynamics in forests. Replicate plots were established at eight locations ranging in elevation from 615 to 1670 m in Great Smoky Mountains National Park in eastern Tennessee, U.S.A. The locations selected ranged from N-poor (low-elevation) to N-rich (high-elevation) forest stands. Soils were sampled in June 1992; plants, forest floors, and upper mineral soils were sampled in August 1992. Net N mineralization and net nitrification potentials for surface mineral soils and organic matter layers at each site were determined by aerobic laboratory incubations. Soils and organic layers from high-elevation sites had greater net N mineralization and nitrification potentials than soils from low-elevation sites. There were significant (P ≤ 0.05) differences between study sites in soil 15N abundance. Therefore, we examined correlations between measures of soil N availability and both mean foliar δ15N values and mean enrichment factors (εp−s = δ15Nleaf − δ15Nsoil). In evergreens, maples, and ferns, mean foliar δ15N values and mean enrichment factors were positively correlated with net N mineralization and net nitrification potentials in soil. The observed relationships between natural 15N abundance in plant leaves and soil N availability were explained by a simple model of soil N dynamics. The model predicts how the isotopic composition of plant N is affected by the following factors: (i) varying uptake of soil NH4-N and NO3-N, (ii) the isotopic composition of different soil N pools, and (iii) relative rates of soil N transformations.


Sign in / Sign up

Export Citation Format

Share Document