Linking Nitrogen Mineralization and Plant Nitrogen Demand with Thermal Units

2015 ◽  
pp. 49-79 ◽  
Author(s):  
C. Wayne Honeycutt
Keyword(s):  
Nitrogen Mineralization ◽  
Plant Nitrogen ◽  
Nitrogen Demand

Nitrate Losses From Disturbed Forests: Patterns and Mechanisms

1979 ◽  
Vol 25 (4) ◽  
pp. 605-619 ◽  
Author(s):  
Peter M. Vitousek ◽  
Jerry M. Melillo
Keyword(s):  
Nitrogen Mineralization ◽  
Nitrogen Uptake ◽  
Plant Uptake ◽  
Drainage Water ◽  
Nitrate Transport ◽  
Plant Nitrogen ◽  
Nitrate Losses ◽  
Wide Range ◽  
Plant Nitrogen Uptake ◽  
Disturbed Forest

Abstract Losses of nitrate in drainage water from disturbed forest ecosystems vary over a wide range. High losses of nitrate to streamwater or groundwater have been observed in a few sites, while in others only small increases in losses have occurred. A limited set of mechanisms could be responsible for such differences. Before disturbance, annual nitrogen mineralization and plant nitrogen uptake vary widely among temperate forests, with higher rates observed in deciduous forests. Destructive disturbance increases nitrogen mineralization and (at least briefly) reduces plant uptake. The nitrogen mineralized in excess of plant uptake could be lost to streamwater or groundwater, lost to the atmosphere through ammonia volatilization or denitrification, or retained within the disturbed system through nitrogen immobilization by decomposers, clay fixation of ammonium, lags in nitrification, nitrate reduction to ammonium, nitrate adsorption on soil colloids, a lack of water for nitrate transport, or (once plant regrowth is established) plant nitrogen uptake. Systematic studies of these mechanisms will allow the development of a more thorough understanding of the nitrogen cycle in disturbed ecosystems. Such an understanding should in turn permit the prediction of nitrate losses from distrubed forests. Forest Sci. 25:605-619.

scholarly journals Amino acid production exceeds plant nitrogen demand in Siberian tundra

2018 ◽  
Vol 13 (3) ◽  
pp. 034002 ◽  
Author(s):  
Birgit Wild ◽  
Ricardo J Eloy Alves ◽  
Jiři Bárta ◽  
Petr Čapek ◽  
Norman Gentsch ◽  
...  
Keyword(s):  
Amino Acid ◽  
Acid Production ◽  
Amino Acid Production ◽  
Plant Nitrogen ◽  
Nitrogen Demand

The influence of nitrogen nutrition of Desmodium uncinatum on seed production

1973 ◽  
Vol 24 (5) ◽  
pp. 667 ◽  
Author(s):  
TA Gibson ◽  
LR Humphreys
Keyword(s):  
Ammonium Nitrate ◽  
Seed Production ◽  
Seed Yield ◽  
Nitrogen Nutrition ◽  
Floral Initiation ◽  
Plant Nitrogen ◽  
Development Stages ◽  
Whole Plant ◽  
Initiation Stage ◽  
Nitrogen Demand

Desmodium uncinaium cv. Silverleaf was grown in simulated swards well supplied with water and basal nutrients. Nodulated control swards yielded 179 g m-2; whole plant nitrogen accretion was 25 g m-2. The rate of nitrogen uptake decreased during seed maturation and redistribution of nitrogen from leaf, stem, and raceme was inadequate to meet the nitrogen demand of maturing seeds. Ammonium nitrate applied at 16.9 kg nitrogen ha-1 wk-1 from the immediate pre-floral initiation stage or at later development stages increased seed yield by 21 to 31 % according to timing. Applied nitrogen increased the number of racemes differentiated per runner and the size of seeds, and decreased the number of seeds formed per floral node. Components of seed yield such as raceme number per runner, floral nodes per raceme, seeds per node, and seed weight were influenced by position on the plant. The greater part of the ammonium nitrate response was due to increased seed production from the secondary racemes on the larger primary runners.

scholarly journals Assessment of Nitrogen Leaching of Cropping Pattern by Soil Nitrogen Balance Equation (Case Study: Varamin Irrigation and Drainage Network)

2017 ◽  
Vol 11 (4) ◽  
pp. 30 ◽  
Author(s):  
Maryam Yousefi ◽  
Jaber Soltani ◽  
Ali RahimiKhob ◽  
Mohammad Ebrahim Banihabib ◽  
Elyas Soltani
Keyword(s):  
Soil Nitrogen ◽  
Nitrogen Fertilizer ◽  
Nitrogen Balance ◽  
Nitrogen Concentration ◽  
Cropping Pattern ◽  
Potential Yield ◽  
Plant Nitrogen ◽  
Concentration Equation ◽  
Nitrogen Demand ◽  
Soil Nitrogen Balance

Nitrogen is often one of the most important limiting factors for biomass production. Usually few soils have proper amount of nitrogen, so it is usually added by fertilizers. In cropping systems, nitrogen fertilization practices can provide a sufficient nitrogen supply for plants to achieve the potential yield. However, to ensure reaching to this potential yield, farmers often apply more nitrogen fertilizers than the required nitrogen for achieving maximum yield. Nitrogen fertilizer should be given to soil according to nitrogen content of soil, water and crop nitrogen demand during the growth periods. Especially in the lands that apply wastewater and groundwater for irrigation and irrigation sources have large quantities of nitrogen, therefore we Should reduce the amount of fertilizer used in agricultural lands, In other words for planning the plant fertilizer demand, nitrogen balance in soil should be considered. Nitrogen overuse increases the risk of nitrogen leaching to groundwater, contaminating groundwater and threatening the human health. In recent years, critical plant nitrogen concentration equation is used to determine crop nitrogen demand during the different growth stages of plants. The purpose of this study is to determine the nitrogen demand of Varamin network’s cropping pattern by using the critical plant nitrogen concentration equation and comparing the result with the amount of nitrogen fertilizer commonly applied in the study area. In this study, monthly biomass production for growing period was determined based on normalized water productivity index and plant canopy development. Coefficient of critical nitrogen concentration equation for each plant was determined by previous researches. The result of this study showed that for barley, the amount of nitrogen applied in Varamin network is equal to nitrogen demand of the cropsand for wheat, maize and tomato are 25%, 61% and 18%, respectively, higher than the amount obtained from critical plant nitrogen concentration equation.also according to the results of soil Nitrogen balance in lands covered by AU canal of Varamin network, 707 ton of nitrogen entered to soil and groundwater by leaching and we should considered appropriate solutions to reduce leaching, such as using high-yielding crops that remove a significant amount of N in the harvested portion, synchronizing fertilizer application with crop demand, conjunctive use of wastewater and groundwater with proper nitrogen concentration and etc.

scholarly journals Agricultural Management Affects Root-Associated Microbiome Recruitment Over Maize Development

2019 ◽  
Vol 3 (4) ◽  
pp. 260-272 ◽  
Author(s):  
Cassandra J. Wattenburger ◽  
Larry J. Halverson ◽  
Kirsten S. Hofmockel
Keyword(s):  
Developmental Stages ◽  
Cropping Systems ◽  
Cropping System ◽  
Amplicon Sequencing ◽  
Bulk Soil ◽  
Vegetative Stage ◽  
Plant Nitrogen ◽  
Conventional Systems ◽  
Root Microbiome ◽  
Nitrogen Demand

Diversified cropping systems provide yield benefits that may result from enhanced nutrient availability via the root microbiome. We hypothesized that root-associated microbial communities in diversified and conventional systems would differ most during high plant nitrogen demand, reflecting microbiome-derived benefits, and that these effects would be greatest nearest the root. We compared maize bulk soil, rhizosphere, and rhizoplane prokaryotic and fungal communities in diversified and conventional systems at four plant developmental stages using amplicon sequencing. The greatest differences between systems in root-selected prokaryotic community composition occurred within the rhizoplane during vegetative stage 11 (high nitrogen demand). During this period, the rhizoplane of maize from the diversified, compared with the conventional, cropping system hosted higher abundances of bacteria implicated in complex organic matter decomposition (Verrucomicrobia and Acidobacteria). In contrast, fungal root-associated communities differed most between cropping systems during vegetative stage 4 (low nitrogen demand) and became more similar over time. Unexpectedly, prokaryotic rhizosphere communities, unlike rhizoplane communities, did not always differentiate from bulk soil communities, indicating value in differentiating between root compartments to understand root−microbiome−management interactions. For example, the diversified system rhizosphere and bulk soil prokaryotic communities were not well differentiated compared with the conventional system, indicating the possibility of a camouflage effect.

Decomposition and nitrogen mineralization from green manures intercropped with coffee tree

2018 ◽  
Vol 13 (1) ◽  
pp. 23
Author(s):  
Rosileyde Golçalves Siqueira Cardoso ◽  
Adriene Woods Pedrosa ◽  
Mateus Cupertino Rodrigues ◽  
Ricardo Henrique Silva Santos ◽  
Paulo Roberto Cecon ◽  
...  
Keyword(s):  
Nitrogen Mineralization ◽  
N Mineralization ◽  
Dry Matter ◽  
Nitrogen Concentration ◽  
Growth Time ◽  
Dry Matter Content ◽  
Green Manures ◽  
Coffee Tree ◽  
Jack Bean ◽  
Hyacinth Bean

The knowledge about the rate of decomposition and nitrogen mineralization of green manures provides synchronization with the higher absorption stage by the coffee tree. The rate of decomposition and nitrogen mineralization varies according to the species of green manure and with the environmental factors. The aim of the present study was to evaluate the decomposition and nitrogen mineralization of two green manures intercropped with coffee trees for three different periods. The experiment was divided into two designs for statistical analysis, one referring to the characterization of plant material (fresh mass, dry matter, dry matter content, nitrogen concentration and accumulation in the jack bean (Canavalia ensiformis) and hyacinth bean (Dolichos lablab) and another to evaluate the rate of decomposition and N mineralization of these species. The decomposition rate decreased in both species as their growth time increased in the field. The decomposition was influenced by the phenology of green manures. Nitrogen mineralization of the jack bean decreased as the growth period in the field increased and was faster than hyacinth bean only when cut at 60 days. The N mineralization was slower than mass decomposition in both species.

МАТЕМАТИЧЕСКОЕ МОДЕЛИРОВАНИЕ ДИНАМИКИ МИНЕРАЛЬНОГО ПИТАНИЯ РАСТЕНИЙ В СИСТЕМЕ «УДОБРЕНИЕ-ПОЧВА-РАСТЕНИЕ»

2020 ◽  
Vol 65 (6) ◽  
pp. 1219-1229
Author(s):  
В.А. Четырбоцкий ◽  
◽  
А.Н. Четырбоцкий ◽  
Б.В. Левин ◽  
◽  
...  
Keyword(s):  
Experimental Data ◽  
Temporal Dynamics ◽  
Plant Biomass ◽  
Environmental Parameters ◽  
Parametric Identification ◽  
Agricultural Crop ◽  
Parameter System ◽  
Plant Nitrogen ◽  
Rhizosphere Microorganisms ◽  
Nitrogen Phosphorus

A numerical simulation of the spatial-temporal dynamics of a multi-parameter system is developed. The components of this system are plant biomass, mobile and stationary forms of mineral nutrition elements, rhizosphere microorganisms and environmental parameters (temperature, humidity, acidity). Parametric identification and verification of the adequacy of the model were carried out based on the experimental data on the growth of spring wheat «Krasnoufimskaya-100» on peat lowland soil. The results are represented by temporal distributions of biomass from agricultural crop under study and the findings on the content of main nutrition elements within the plant (nitrogen, phosphorus, potassium). An agronomic assessment and interpretation of the obtained results are given.

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