The random testability of the n-input AND gate

Four experiments were conducted with eighteen lambs sustained entirely by intragastric nutrition at gross energy inputs varying from 430 to 860 kJ/kg live weight0·75 (W0·75). Isolated rumen micro-organisms (RMO) were infused into the abomasum in quantities varying from 0 to 2 g digestible N/kg W0·75 to assess the increase in N balance as a result of increasing RMO input when N was limiting.The over-all utilization of N from RMO (RMO-N) could be described by the equation y = 0·543 x −0·457, residual SD = 0·037, where y is the N balance and x is the abomasal input of RMO-N, both expressed in g/kg W0·75. Thus the coefficient of efficiency of utilization of infused RMO-N was 0·543 (SE 0·008). The coefficient of efficiency of utilization of RMO-N truly digested (i.e. the biological value) was 0·659 (SE 0·015).The RMO-N input (mean with SE) at N equilibrium was 0·843 (0·009) g/kg W0·75. The true digestibility of RMO-N was 0·813 (0·004). The urinary N excretion when no N was infused was 0·329 (0·008) g/kg W0·75 and the N excreted via the faeces with zero N input was 0·036 (0·009) g/kg W0·75.

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Fixação biológica de nitrogênio no Semiárido Brasileiro (Biological nitrogen fixation in the Brazilian Semiarid)

Revista Brasileira de Geografia Física ◽

10.26848/rbgf.v8.0.p585-597 ◽

2015 ◽

Vol 8 ◽

pp. 585

Author(s):

Ana Dolores Santiago de Freitas ◽

Everardo Sampaio ◽

Carolina Santos ◽

Aleksandro Silva ◽

Renata Carvalho

Keyword(s):

Nitrogen Fixation ◽

Biological Nitrogen Fixation ◽

Plant Density ◽

Tree Cover ◽

Semiarid Region ◽

Legume Species ◽

Natural Ecosystems ◽

Brazilian Semiarid ◽

N Input ◽

Biological Nitrogen

A fixação biológica de nitrogênio (FBN) é a principal forma de entrada de N em ecossistemas naturais e em sistemas agrícolas de subsistência, como os praticados predominantemente no Semiárido brasileiro. Estimativas dos aportes de N na Caatinga e em cultivos de importância para a região ainda são escassas, em parte pela dificuldade de medir simultaneamente as proporções de N derivadas da atmosfera (%Ndda) e as produções de biomassa no mesmo sistema. Estudos pioneiros indicam que diversas espécies de leguminosas, herbáceas e arbóreas, nativas e/ou cultivadas, podem fixar elevadas proporções de seu N. Em Caatinga bem preservada, os aportes de N em leguminosas arbóreas foram estimados em 11 kg ha-1 ano-1, um valor relativamente baixo devido à baixa densidade de plantas fixadoras. Entretanto, a densidade de leguminosas fixadoras na vegetação não é o único fator definindo o aporte de N, pois há observações de ausência de FBN em áreas de Caatinga em regeneração, dominadas por espécies fixadoras. No estrato herbáceo, os aportes de N podem chegar a 6 kg ha-1 ano-1, nas áreas com menor cobertura de arbóreas. As quantidades de N fixadas nos diferentes sistemas de cultivo são pouco conhecidas. Para o feijão-caupi, a FBN pode se aproximar dos 30 kg ha-1, em cultivos consorciados com milho, chegando a 45 kg ha-1, em cultivos solteiros. Em cultivos irrigados, adubos verdes podem adicionar 185 kg ha-1, superando a quantidade exportada nas colheitas. Em sistemas agroflorestais, a adição anual de N pode chegar a 40 kg ha-1. Não existem estimativas do N fixado em gramíneas na região, mas algumas espécies apresentem potencial de FBN. Biological nitrogen fixation (BNF) is the main N input in natural ecosystems and in subsistence agricultural systems, such as those commonly practiced in the Brazilian semiarid region. Estimates of N inputs in Caatinga and the main regional crops are still scarce, partly due to the difficulty in measuring concomitantly the proportion of plant N derived from the atmosphere (%Ndfa) and the amount of biomass produced in the same system. Pioneer studies indicate that several legume species, herbs and trees, native and/or cultivated, can fix large proportions of their N. In mature Caatinga, N inputs in tree legumes were estimated at 11 kg ha-1 year-1, a relatively low value due to the low plant density of the legume species. However, plant density is not the only factor defining N input, since absence of fixation has been reported in regenerating Caatinga, even in those dominated by potentially fixing species. In the herb stratum, N input up to 6 kg ha-1 year-1 has been reported in areas with lower tree cover. Inputs in crop systems are largely unknown. Fixation in cowpea can reach 30 kg ha-1, in plants consortiated with corn, and 45 kg ha-1, in single crop. Under irrigation, green manure crops can add 185 kg ha-1 of fixed N, more than the amounts exported by the main crop. In agroforest systems, the annual input may reach 40 kg ha-1. There are no publish reports on N biologically fixed by Poaceae species growing in the semiarid region but it is known that some species have the potential to fix. Keywords: N-15 natural abundance, slash and burn agriculture, diazotrophic microorganism, rhizobia, symbiosis.

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Linking nitrogen load to the structure and function of wetland soil and rhizosphere microbial communities

10.1101/197855 ◽

2017 ◽

Author(s):

Eric R Hester ◽

Sarah F. Harpenslager ◽

Josepha MH van Diggelen ◽

Leon L Lamers ◽

Mike SM Jetten ◽

...

Keyword(s):

Microbial Communities ◽

Greenhouse Gas Emissions ◽

Greenhouse Gas ◽

Amplicon Sequencing ◽

N Fertilization ◽

Wetland Soil ◽

N Availability ◽

Gas Emissions ◽

16S Rrna Amplicon Sequencing ◽

N Input

AbstractWetland ecosystems are important reservoirs of biodiversity and significantly contribute to emissions of the greenhouse gases CO2, N2O and CH4. High anthropogenic nitrogen (N) inputs from agriculture and fossil fuel combustion have been recognized as a severe threat to biodiversity and ecosystem functioning such as control of greenhouse gas emissions. Therefore it is important to understand how increased N input into pristine wetlands affects the composition and activity of micro-organisms, especially in interaction with dominant wetland plants. In a series of incubations analyzed over 90 days, we disentangle the effects of N fertilization on the microbial community in bulk soil and the rhizosphere ofJuncus acutiflorus, a common and abundant graminoid wetland plant. We observed an increase in greenhouse gas emissions when N is increased in incubations withJ. acutiflorus, changing the system from a greenhouse gas sink to a source. Using 16S rRNA amplicon sequencing and metagenomics, we determined that the bacterial orders Opitutales, Subgroup-6 Acidobacteria and Sphingobacteriales significantly responded to high N availability and we hypothesize that these groups are contributing to the increased greenhouse gas emissions. These results indicated that increased N input leads to shifts in microbial activity within the rhizosphere, severely altering N cycling dynamics. Our study provides a framework for connecting environmental conditions of wetland bulk and rhizosphere soil to the structure and metabolic output of microbial communities.

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Assessing Nitrogen Legacies in Western Europe

10.5194/egusphere-egu21-14526 ◽

2021 ◽

Author(s):

Andreas Musolff ◽

Sophie Ehrhardt ◽

Rémi Dupas ◽

Rohini Kumar ◽

Pia Ebeling ◽

...

Keyword(s):

Time Series ◽

Agricultural Land ◽

Time Lags ◽

Water Safety ◽

Biological Fixation ◽

Nitrogen Inputs ◽

Wide Range ◽

N Input ◽

Nitrate Concentrations ◽

Input Time

<p>Intensive agricultural land use have introduced vast quantities of nutrients such as reactive nitrogen (N) to soils and subsequently to groundwater and surface waters. High nitrate concentrations are still a pressing issue for drinking water safety and aquatic ecosystem health e.g. in Europe, although fertilizer inputs have been significantly lowered in the last decades. This is partly due to a slow response of riverine nitrate concentrations to changes in nitrogen inputs attributed to N legacies in catchments. N can be stored organically bound as a biogeochemical legacy in soils or can be slowly transported as nitrate in groundwater forming a hydrologic legacy. Legacy can thus lead to a net retention of N in catchments and to substantial time lags in the response to input changes. Here, we systematically explore legacy effects over a wide range of catchment in the Western European countries France and Germany. We are making use of long observational time series of nitrate concentration in 238 catchments covering 40% of the total area of France and Germany. We apply a Weighted Regression on Time, Discharge, and Season (WRTDS) to derive continuous daily flow-normalized concentrations and loads. The temporal pattern of concentration and loads at the catchment outlet is compared to the N input time series evolving from agricultural N surplus, atmospheric deposition and biological fixation. We found that on long-term catchments retain on average 72% of the N input. Time lags between input and output were successfully explained by a lognormal transport time distribution. The modes of these distributions were found to be rather short with a median mode of 5.4 years across all catchments. Based on this data-driven assessment only the fate of N in the catchments is hard to assess as denitrification in soil and groundwater can lead to similar observations as the storage of N in legacies. Focusing on the mobile part of N that is exported by catchments, we estimate that a substantial amount of N is still stored in the subsurface that will be released in the coming years. We therefore analyzed how catchment nitrate export will evolve under the scenario of a total cut down, reduced or constant future N inputs. We report the expected timescale of reaction to implemented measures to help tackling this pressing water quality problem.</p>

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Seasonal variability of organic matter and N input with litterfall in Scots pine stands

Nutrients in Ecosystems - Changes of Atmospheric Chemistry and Effects on Forest Ecosystems ◽

10.1007/978-94-015-9022-8_11 ◽

1998 ◽

pp. 177-186 ◽

Cited By ~ 2

Author(s):

C. Bergmann ◽

T. Fischer ◽

R. F. Hüttl

Keyword(s):

Organic Matter ◽

Scots Pine ◽

Seasonal Variability ◽

N Input ◽

Pine Stands ◽

Scots Pine Stands

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The Effect of Nitrogen Input on Chemical Profile and Bioactive Properties of Green- and Red-Colored Basil Cultivars

Antioxidants ◽

10.3390/antiox9111036 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1036 ◽

Cited By ~ 1

Author(s):

Luís R. O. Cruz ◽

Ângela Fernandes ◽

Francesco Di Gioia ◽

Spyridon A. Petropoulos ◽

Nikolaos Polyzos ◽

...

Keyword(s):

Fatty Acids ◽

Nutritional Value ◽

Quadratic Function ◽

Omega 3 ◽

Chemical Profile ◽

Chemical Parameters ◽

Leaf Extracts ◽

N Input ◽

Omega 6 ◽

Antibacterial And Antifungal

In the present study, three red-colored (Dark Opal, Basilico Rosso, and Red Basil) and one green-colored landrace (Mitikas) of basil (Ocimum basilicum L.) were grown under four nitrogen regimes, namely Control (no fertilizer added), 200 ppm, 400 ppm, and 600 ppm of nitrogen (N). Fresh yield varied depending on N input following a quadratic function in all four genotypes, and green basil performed better compared to the red cultivars. A significant interaction of genotype × N input was recorded for most of the chemical parameters measured. Tocopherols contents of leaves were consistently higher in plants that received 200 ppm of N and lower in those receiving 600 ppm of N, especially in Dark Opal and Red Basil cultivars. Polyunsaturated fatty acids (PUFA) were the major category of fatty acids and Red Basil had the lowest ratio of omega-6/omega 3 (0.29) and thus the best fatty acid profile. Polyphenols content was the highest in Red Basil and Dark Opal (25 mg/g of extract on average) and the lowest in Mitikas and decreased with increasing N input. Similarly, antioxidant activity was the highest in Dark Opal and Red Basil fertigated with 200 ppm of N, whereas all the leaf extracts tested had good antibacterial and antifungal activity. In conclusion, basil chemical and bioactive profile was significantly influenced by both genotype and N input. Red-colored basil, although less productive, had the best chemical profile, and moderate levels of N input may provide the best compromise between yield, nutritional value, and bioactivity for the species.

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