Inorganic Nitrogen Retention by Watersheds at Fernow Experimental Forest and Coweeta Hydrologic Laboratory

Four restored wetlands dominated by Phragmites australis, Typha latifolia and Scirpus lacustris were used to improve the quality of agricultural runoff in the Delta of the Ebro River (NE Spain) in 1993. The wetlands were continuously flooded with water from a ricefield irrigation network during the growing season and received water with between 0-270 mg m−2d−1 of total nitrogen, 29-105 mg m−2d−1 of dissolved inorganic nitrogen and 0-27 mg m−2d−1 of dissolved organic nitrogen. Surface outflows contained between 0-80 mg m−2d−1 of total nitrogen, 0-12 mg m−2d−1 of dissolved inorganic nitrogen and 1-19 mg m−2d−1 of dissolved organic nitrogen. The nitrogen retention efficiency was close to 100% of the input, except for dissolved organic nitrogen at the end of the growing season. The denitrification rates measured by the acetylene reduction in the sediment ranged between 0 and 3.46 mg N m−2 d−1 and represented between 0 and 12% of the inflowing dissolved inorganic nitrogen. Emergent macrophytes accumulated between 20 and 100 mg N m−2 d−1, which accounts for between 66 and 100% of the inflowing dissolved inorganic nitrogen. The wetland sediment accumulated between 111 and 250 mg N m−2 d−1 during the six month growing season. The removal rate constants calculated according to a first - order plug - flow kinetics, were between 0.01-0.075 m d−1 for total nitrogen and 0.01-0.3 m d−1 for dissolved inorganic nitrogen. Plant uptake, detritus accumulation and decomposition, and nitrogen recycling in the sediment are major processes for nitrogen retention and recycling in the wetlands. This type of wetlands, restored from ricefields, act as highly efficient water polishing filters for agricultural runoff and, at the same time, can contribute to increase the habitat biodiversity of large areas where rice is cultivated extensively.

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Inorganic nitrogen immobilization in live and sterile soil of old-growth conifer and hardwood forests: implications for ecosystem nitrogen retention

Biogeochemistry ◽

10.1007/s10533-011-9627-6 ◽

2011 ◽

Vol 111 (1-3) ◽

pp. 169-186 ◽

Cited By ~ 23

Author(s):

David Bruce Lewis ◽

Jason P. Kaye

Keyword(s):

Inorganic Nitrogen ◽

Nitrogen Retention ◽

Hardwood Forests ◽

Nitrogen Immobilization ◽

Sterile Soil ◽

Old Growth

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Self-purification process and retention of nitrogen in floodplains of River Nemunas

Hydrology Research ◽

10.2166/nh.2010.109 ◽

2010 ◽

Vol 41 (3-4) ◽

pp. 338-345 ◽

Cited By ~ 7

Author(s):

Saulius Vaikasas ◽

Antanas Dumbrauskas

Keyword(s):

Hot Spot ◽

Inorganic Nitrogen ◽

Nitrogen Concentration ◽

Nitrogen Retention ◽

Suspended Sediments ◽

Curonian Lagoon ◽

Purification Process ◽

Nitrogen Runoff ◽

The Baltic ◽

Baltic Sea Basin

Due to its catchment size and its significant level of agricultural pollution, the Nemunas river basin has been identified as an agricultural hot spot in the Baltic Sea basin. On average, the total annual inorganic nitrogen runoff into the river is 26.9 × 106 kg, which corresponds to a load of 275 kg km−2 yr−1. A submerged floodplain, covering 605 km2 of the River Nemunas lowland, maintains the natural retention threshold for pollutants in the water of the main canal and the outfall at Curonian Lagoon, as well as improving farming conditions in the inundated meadows of the valley. It also increases the sedimentation and nitrogen retention capacities of the Nemunas catchment. It has been estimated that about 40% of the fine suspended sediments can be retained and deposited in the flooded meadows of the delta. Controlled inundation of the floodplains in the Nemunas delta may reduce its runoff nitrogen load by 21 kg km−2 per flood event. As a result, nitrogen concentration decreases by approximately 8–10%, causing a self-purification process in the flooded area. Nitrogen retention is dependent upon the velocities of the flood current and has mostly been observed in zones of stagnating water.

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Inorganic nitrogen retention in acid-sensitive lakes in southern Norway and southern Ontario, Canada?a comparison of mass balance data with an empirical N retention model

Hydrological Processes ◽

10.1002/hyp.1249 ◽

2003 ◽

Vol 17 (12) ◽

pp. 2393-2407 ◽

Cited By ~ 26

Author(s):

�. Kaste ◽

P. J. Dillon

Keyword(s):

Mass Balance ◽

Inorganic Nitrogen ◽

Nitrogen Retention ◽

Retention Model ◽

Southern Ontario ◽

N Retention ◽

Southern Norway

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Cropland abandonment enhances soil inorganic nitrogen retention and carbon stock in China: A meta-analysis

Land Degradation and Development ◽

10.1002/ldr.3137 ◽

2018 ◽

Vol 29 (11) ◽

pp. 3898-3906 ◽

Cited By ~ 1

Author(s):

Dashuan Tian ◽

Yangzhou Xiang ◽

Bingxue Wang ◽

Meiling Li ◽

Yanshu Liu ◽

...

Keyword(s):

Carbon Stock ◽

Inorganic Nitrogen ◽

Meta Analysis ◽

Nitrogen Retention ◽

Soil Inorganic Nitrogen ◽

Cropland Abandonment ◽

Soil Inorganic

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Influence of moderate phosphate addition on nitrogen retention in an acidic boreal lake

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f04-233 ◽

2005 ◽

Vol 62 (2) ◽

pp. 312-321 ◽

Cited By ~ 10

Author(s):

Øyvind Kaste ◽

Anne Lyche-Solheim

Keyword(s):

Inorganic Nitrogen ◽

Nitrogen Retention ◽

Inorganic Phosphorus ◽

Acidic Lake ◽

Growing Seasons ◽

Coastal Marine ◽

P Fertilizer ◽

Important Regulator ◽

Marine Areas ◽

N Loading

Inorganic phosphorus (P) fertilizer was added to a small, acidic lake in southernmost Norway to test the potential of this technique to increase the retention of total inorganic nitrogen (TIN) and thereby mitigate the effects of elevated leaching of atmospherically derived N. The experiment was conducted over 4 years (1 pretreatment year followed by 3 years with weekly P additions during the growing season). To avoid any undesirable eutrophication effects, the total P concentration was increased from 45 µg P·L1 to a moderate level of 1012 µg P·L1. Compared with the pretreatment year, the P additions increased the average TIN retention in the experimental lake by nearly 70% (from 53 to 88 mmol·m2·year1) during three growing seasons. However, when considering that the reference lake experienced a 55% decrease in TIN retention during the same period, the increase might have been even larger. This underlines the role of P (both natural and anthropogenic) as an important regulator of N retention in upland lake districts that in large parts of southernmost Norway contribute significantly to the N loading on coastal marine areas.

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The additive effect of biochar amendment and simulated nitrogen deposition stimulates the plant height, photosynthesis and accumulation of NPK in pecan (Carya illinoinensis) seedlings

AoB Plants ◽

10.1093/aobpla/plaa035 ◽

2020 ◽

Vol 12 (4) ◽

Author(s):

Zhiying Hou ◽

Yiquan Tang ◽

Caiyun Li ◽

Kean-Jin Lim ◽

Zhengjia Wang

Keyword(s):

Nitrogen Content ◽

Bulk Density ◽

Nitrogen Deposition ◽

Inorganic Nitrogen ◽

Combined Treatment ◽

Nitrogen Retention ◽

Soil Bulk Density ◽

Carya Illinoinensis ◽

Chlorophyll Pigments ◽

Biochar Amendment

Abstract This work investigated the effective doses of biochar (BC) amendment with simulated nitrogen deposition on the stimulation of pecan (Carya illinoinensis) growth. A total of nine conditions combining three levels of BC—BC0, 0 t ha−1 year−1; BC20, 20 t ha−1 year−1; and BC40, 40 t ha−1 year−1—and three levels of simulated nitrogen deposition—N0, 0 kg N ha−1 year−1; N50, 50 kg N ha−1 year−1; and N150, 150 kg N ha−1 year−1—were applied throughout 1 year on the pecan-grafted seedlings of cultivar ‘Pawnee’. The growth, photosynthesis, chlorophyll and nutrient content in the seedlings were measured. The soil bulk density, pH, nitrogen content and enzymatic activities were also measured. Biochar amendment reduced soil bulk density and elevated soil pH. Meanwhile, aided by BC amendment, the inorganic nitrogen content and enzyme activities increased with increasing doses of nitrogen. In the absence of BC amendment, the seedlings’ height, photosynthesis and chlorophyll pigments were only stimulated by a low level of simulated nitrogen deposition (N50), whereas a high level of simulated nitrogen deposition (N150) impeded the growth. The seedlings improved the most under the combined treatment of BC20N150, wherein the seedling heights, photosynthesis and total chlorophyll improved by 22 %, 70 % and 40 %, respectively, compared to those treated solely with BC20. Further increase of nitrogen retention in the soil by the BC40 did not further improve the growth of the seedlings, suggesting the possible mechanisms involve nutrient uptake and usage dynamic in the seedlings. The BC amendment alleviated the antagonist effect from simulated nitrogen deposition that suppressed the absorption of phosphorus, potassium and iron. The effect of applying both BC amendment and simulated nitrogen deposition to the growth of seedlings was additive at fertilizing tree species.

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