scholarly journals Effect of preferential transport and coherent denitrification on leaching of nitrate to drainage

2020 ◽  
Author(s):  
David Nagy ◽  
Annette E. Rosenbom ◽  
Bo V. Iversen ◽  
Finn Plauborg
Keyword(s):  
Aquatic Environment ◽  
Dry Matter ◽  
Field Scale ◽  
N Loss ◽  
Model Concept ◽  
Total N ◽  
N Yield ◽  
Reduction Function ◽  
Preferential Transport

Abstract. To protect the quality of the aquatic environment, it is imperative to be able to assess the leaching of nitrate through various hydrogeological settings. Numerical model concepts have been developed in order to describe this leaching and possible routes of nitrogen at field scale, often without being evaluated in regard to their ability to account for dominant preferential transport and coherent denitrification, which is the rule rather than the exception in soils. This study evaluates whether it is possible to describe 10-years of nitrate concentrations, measured in drainage from a tile-drained agricultural clay till field in Denmark, by applying the soil-plant-atmosphere model DAISY, capable of accounting for preferential transport and denitrification. A DAISY model concept, including macropores capable of capturing the water and bromide balance of the field within this specific timeframe, was able to predict the water transport to drainage, dry matter and N-yield of the harvested crops, while it was unable, with the standard default denitrification model, to predict dynamics and quantity of N-loss to drainage. This was caused by a fast saturation of the plow layer, where nitrate seemed to be denitrified almost instantly, and no surplus nitrate remained to be transported to the drainage. To circumvent this and describe the measured N-loss, modification to the water reduction function affecting denitrification was conducted. The denitrification had to be reduced by approximately 50 % from a seasonal average of 75 kg N ha−1 to 35 kg N ha−1 while 48 % to 80 % of the total N-loss to drainage had to be preferentially transported from the plow layer. This study, therefore, reveals that, by not accounting for preferential transport and coherent denitrification, there is a high risk of underestimating leaching of nitrate to the aquatic environment.

ETUDE DE L’EFFET DE LA LUZERNE OU DU TREFLE ROUGE ASSOCIE AU BROME OU A LA FLEOLE DES PRES SUR LA PRODUCTION D’HERBAGE AU LAC ST-JEAN

1982 ◽  
Vol 62 (4) ◽  
pp. 929-934 ◽  
Author(s):  
F. DARISSE ◽  
R. DRAPEAU
Keyword(s):  
Binary Mixture ◽  
Dry Matter ◽  
Red Clover ◽  
Pure Stand ◽  
The Third ◽  
N Yield

The authors have evaluated the development and the quality of timothy and bromegrass grown alone and in mixtures with either alfalfa or red clover. Nitrogen-fertilized grasses yielded on the average more dry matter than their mixture counterpart. Either of the grasses with red clover contributed more evenly to yield than with alfalfa. The highest yield of protein was obtained from the association of alfalfa with timothy or bromegrass whereas these grasses were the poorest protein yielders even with 72–90 kg/ha of applied N. Yield contribution of timothy and bromegrass in mixture with either legume increased over the first two harvest years; timothy, however, maintained this trend through the third year while bromegrass reached an equilibrium or decreased. From a roughage quality stand-point a binary mixture of the grasses with alfalfa is the best, followed by the grasses with red clover and finally, the grasses in pure stand.

EFFECTS OF CUTTING ON THE NITROGEN ECONOMY AND DRY MATTER YIELD OF LABLAB GROWN UNDER MONOCULTURE AND INTERCROPPED WITH MAIZE IN NORTHERN THAILAND

2000 ◽  
Vol 36 (4) ◽  
pp. 459-468 ◽  
Author(s):  
N. R. DEVKOTA ◽  
B. RERKASEM
Keyword(s):  
Dry Matter ◽  
Cropping System ◽  
Soil Surface ◽  
Yield Component ◽  
N Fixation ◽  
Lablab Purpureus ◽  
Area Index ◽  
Total N ◽  
Equivalent Ratio ◽  
N Yield

A study was conducted to examine the effects of the time and severity of cutting lablab (Lablab purpureus), both in sole crops and intercropped with maize (Zea mays). The effects of cutting management on the dry matter (DM) yield, leaf area index (LAI), nodulation, the nitrogen (N) yield, and N fixation by lablab were measured, as were the total DM yield, grain yield, and a yield component of maize.Two dates of lablab cutting (40 and 60 d after sowing (DAS)), and two heights of cutting (30 and 20 cm above the soil surface) were applied in factorial combinations as well as a no-cutting treatment. Maize was not cut either in monoculture or intercrops.Intercropping lablab with maize increased the grain yields of maize from 3.2 t ha−1 to 3.8 t ha−1 if lablab was cut at 40 DAS, but delaying cutting until 60 DAS had no effect, while uncut lablab reduced the yield of maize by 10%. Intercropping lablab with maize reduced the total N yield of lablab by over 50%, from 302 to 132 kg N ha−1. Regardless of cropping system, the total N yield of lablab at 130 DAS was 24% less when lablab was cut at 60 DAS compared with 40 DAS. Cutting height did not significantly affect the total N yield of lablab. Although both cropping system and cutting time significantly affected the total N fixation by lablab at 130 DAS, there were no significant effects of cropping system, cutting time or severity of cutting on the proportion of N in lablab derived from N fixation.Values of Land Equivalent Ratio (LER) which ranged between 1.2 and 1.6, and of Area Time Equivalent Ratio (ATER) which ranged between 1.0 and 1.4 for intercrops of maize with lablab indicated a definite advantage of intercropping. LER and ATER values were greatest when lablab was uncut, and least when lablab was cut at 60 DAS.

RESPONSE OF ORCHARD GRASS TO MULTIPLE HARVESTS AND RATES OF NITROGEN IN POST-SEEDING YEARS

1977 ◽  
Vol 57 (3) ◽  
pp. 763-770
Author(s):  
H. T. KUNELIUS ◽  
MICHIO SUZUKI
Keyword(s):  
Dry Matter ◽  
Dactylis Glomerata ◽  
Late Summer ◽  
Total N ◽  
Orchard Grass ◽  
Nitrate N ◽  
Dactylis Glomerata L ◽  
N Rates

Frode orchard grass (Dactylis glomerata L.) was fertilized with 99–495 kg N/ha/yr in three equal applications and harvested three or four times per season over a 3-yr period to determine the productivity, quality of forage and persistence of stands. The application of N resulted in significant (P =.001) linear and quadratic increases in dry matter (DM) yields. Higher DM yields were obtained with the 3-harvest system while the yield distribution within the season was more uniform for the 4-harvest system. Total N concentrations of orchard grass increased linearly with the N rates. Total N yields were dependent on the rates of applied N with the recovery of applied N ranging from 39 to 70% at 99–297 kg N/ha/yr, respectively. The in vitro disappearance of DM was slightly reduced by the high N rates in the 1st and 2nd harvests. The nitrate-N concentrations were highest in the early and late summer ranging from.11 to.29% at 297–495 kg N/ha/yr, respectively. The persistence of orchard grass was better under the 4- than the 3- harvest system.

scholarly journals Milk Production and Quality of Lactating Yak Fed Oat Silage Prepared with a Low-Temperature-Tolerant Lactic Acid Bacteria Inoculant

Foods ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2437
Author(s):  
Mingming Zhu ◽  
Rongqing Xie ◽  
Liangyin Chen ◽  
Minghong You ◽  
Wenlong Gou ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Lactic Acid ◽  
Low Temperature ◽  
Lactic Acid Bacteria ◽  
Milk Yield ◽  
Dry Matter ◽  
Dry Matter Intake ◽  
Fresh Matter ◽  
Total N

This study aimed to investigate the effect of oat silage treated with a low-temperature-tolerant lactic acid bacteria (LAB) inoculant on milk yield and the quality of lactating yaks. Oat silages were prepared in big round bales, treated without (control) or with a low-temperature-tolerant LAB inoculant (a mixture of Lactobacillus plantarum BP18, Pediococcus pentosaceus HS1 and Lactobacillus buchneri LP22; the application rate of 105 cfu/g on a fresh matter basis). Eighteen lactating yaks were divided into nine pairs with a similar milk yield. Each pair of yaks was randomly allocated to the control or LAB-inoculated silage treatment. The inoculated silage increased the dry matter intake and the total volatile fatty acid (mainly acetate, propionate and butyrate) in rumen fluid compared with the control. The inoculated silage also enhanced the yield of yak milk with high contents of total N, fat and lactose. In addition, high levels of essential amino acids (Thr, Leu and Phe), polyunsaturated fatty acids and low saturated fatty acids were observed in milk when lactating yaks were fed with the inoculated silage. Therefore, inoculation with a low-temperature-tolerant LAB during ensiling could promote the milk yield of lactating yaks by enhancing dry matter intake and ruminal fermentation.

scholarly journals Annual dry matter, metabolisable energy and nitrogen yields of six dryland pastures six and seven years after establishment

2010 ◽  
pp. 177-184 ◽  
Author(s):  
A. Mills ◽  
D.J. Moot
Keyword(s):  
White Clover ◽  
Dry Matter ◽  
Subterranean Clover ◽  
Trifolium Subterraneum ◽  
Pasture Quality ◽  
N Yield ◽  
Nitrogen Yields ◽  
Metabolisable Energy ◽  
Lincoln University

Dry matter (DM) yields, botanical composition, liveweight production and pasture quality of six grazed dryland pastures established in 2002 at Lincoln University, Canterbury, are reported for Years 6 (2007/08) and 7 (2008/09). Lucerne (Medicago sativa) yielded 14.0 t DM/ha/yr and sheep liveweight (LW) production totalled 903 (2007/08) and 1 141 kg/ha/yr (2008/09). Metabolisable energy (ME) on offer (~134 GJ/ha/yr) and N yield (>500 kg/ha/yr) from the lucerne exceeded those of grass-based pastures. Yields (9.8- 11.2 t DM/ha/yr) and liveweight production (814-912 kg/ha/yr) from cocksfoot (Dactylis glomerata) pastures established with subterranean (Trifolium subterraneum) clover were greater than all other grass-based pastures. Annual ME was 79-96 GJ/ha and N yield was 269- 316 kg/ha from the cocksfoot, subterranean clover and volunteer white clover (T. repens) components. For Year 7, the contribution of unsown weeds and grasses in cocksfoot-based pastures was ~28% of total annual yield compared with 55% in ryegrass (Lolium perenne)/ white clover pastures. Consequently, the ME and N yields from sown pasture components in ryegrass/white clover pastures were lower than those from cocksfootbased pastures. These results indicate dryland farms with lucerne and/or cocksfoot/sub clover pastures can produce higher DM yields from more persistent pasture species. Persistence led to more ME and N on offer to grazing livestock, which resulted in higher liveweight production than from the ryegrass pastures. Keywords: balansa clover, Caucasian clover, growth rates, pasture quality, T. ambiguum, T. michelianum

SEEDING YEAR YIELDS AND QUALITY OF ORCHARD GRASS AS INFLUENCED BY N RATES AND HARVEST SYSTEMS

1977 ◽  
Vol 57 (2) ◽  
pp. 427-431
Author(s):  
H. T. KUNELIUS ◽  
MICHIO SUZUKI
Keyword(s):  
Dry Matter ◽  
Dactylis Glomerata ◽  
Total N ◽  
Orchard Grass ◽  
Application Systems ◽  
Nitrate N ◽  
Dactylis Glomerata L ◽  
N Rates

Frode orchard grass (Dactylis glomerata L.) was seeded at 20 kg/ha without a companion crop in 1971 and 1972. Nitrogen was applied at 37–185 kg/ha at seeding and after the first harvest, and the stands were subjected to three harvest systems. Total dry matter (DM) yields increased up to 74 kg N/ha/application. Systems with the latest first harvest and longest regrowth intervals produced highest DM yields. Early seeding was important for the production of high DM yields. Late fall harvest in October resulted in poor winter survival. The total N concentrations of orchard grass ranged from 2.58 to 4.40%, with small or no increases beyond 111 kg N/ha/application. In vitro disappearance of DM was not affected by N rates but varied from 60.7 to 69.8% with the highest readings for the early or short regrowth interval harvests. Nitrate-N concentrations of orchard grass were < 0.15% at 37 kg N/ha/application. At or above 74 kg N/ha/application, nitrate-N usually exceeded 0.15% level which might be potentially toxic to livestock consuming the forage.

EFFECTS OF RATES OF N AND REGROWTH INTERVALS ON YIELDS AND QUALITY OF ITALIAN RYEGRASS GROWN AS A SUMMER ANNUAL

1978 ◽  
Vol 58 (3) ◽  
pp. 691-697 ◽  
Author(s):  
H. T. KUNELIUS ◽  
F. W. CALDER
Keyword(s):  
Dry Matter ◽  
Sandy Loam ◽  
Lolium Multiflorum ◽  
Italian Ryegrass ◽  
Total N ◽  
Harvest Intervals ◽  
The Mean ◽  
Suitable System

Italian ryegrass (IRG) (Lolium multiflorum Lam. cv. Lemtal) was grown on a sandy loam and/or on a fine sandy loam in 1974, 1975, and 1976. IRG was fertilized three times each year with 40, 80, or 120 kg N/ha/application and harvested at 3-, 4-, 5- or 6-wk intervals starting in July. Dry matter (DM) yield increased with the rate of applied N. Four-week harvest intervals generally resulted in the greatest DM yields ranging from 4.32 to 7.11 t/ha. Droughty conditions in 1975 reduced the growth and resulted in small DM yields particularly on sandy loam. The mean total N concentrations of IRG ranged from 2.40 to 3.68% and was approximately proportional to applied N. Longer regrowth intervals decreased total N concentrations by. 12–.56% units per week. Applied N did not influence the in vitro disappearance of DM (IVDDM), whereas longer regrowth intervals reduced IVDDM in 1975. The harvest system with a 4-wk regrowth interval and 80 kg N/ha/apphcation resulted in satisfactory DM, N, and digestible DM yields and appeared to be a suitable system for IRG grown as a summer annual.

scholarly journals Yields, plant characteristics, total N and fibre composition of timothy cultivars grown at two latitudes

1996 ◽  
Vol 5 (4) ◽  
pp. 461-473 ◽  
Author(s):  
H. Tapani Kunelius ◽  
Pertti Pärssinen ◽  
Seppo K. Pullli
Keyword(s):  
Nutritional Quality ◽  
Prince Edward Island ◽  
Dry Matter ◽  
Phleum Pratense ◽  
Yield Stability ◽  
Total N ◽  
Acid Detergent Fibre ◽  
Plant Characteristics ◽  
Phleum Pratense L

Timothy (Phleum pratense L.) cultivars of southern (45°N) and northern (≥60°N) origin were grown in Charlottetown, Prince Edward Island, Canada (46° N) and Jokioinen, Finland (61° N) in two years. Timothy was harvested twice a season and nitrogen applied at 100 or 150 kg/ha. Dry matter yields were higher in Charlottetown than in Jokioinen and northern cultivars outyielded southern cultivars. Nitrogen at 150 kg/ha increased total yields an average of 1.4 t/ha over the 100 kg N/ha rate. The stems and panicles of timothy were longer in Charlottetown. Northern cultivars had longer panicles. The leaf content of cultivars ranged from 139 to 230 g/kg. Northern cultivars had greater N concentrations (22.1 g/kg) in cut 2 than southern timothies (19.7 g/kg). Concentrations of neutral detergent fibre (NDF) and acid detergent fibre (ADF) in cut 1 were lower in Jokioinen, In conclusion, northern cultivars performed well in Charlottetown but there were differences in yield stability among cultivars. Nutritional quality of timothy cultivars varied among the sites and the significance of differences in NDF and ADF in relation to animal performance require further study.

EFFECTS OF NITROGEN RATES AND HARVEST SCHEDULES ON YIELD AND QUALITY OF WESTERWOLDS RYEGRASS GROWN AS A SUMMER ANNUAL

1980 ◽  
Vol 60 (2) ◽  
pp. 519-524 ◽  
Author(s):  
H. T. KUNELIUS
Keyword(s):  
Dry Matter ◽  
Lolium Multiflorum ◽  
Matter Content ◽  
In Vitro Digestibility ◽  
Dry Matter Content ◽  
Total N ◽  
Yield And Quality ◽  
Nitrogen Rates

Westerwolds ryegrass (Lolium multiflorum Lam. ’Promenade’) was grown on fine sandy and light loam soils. Nitrogen was applied at 40, 80, or 120 kg/ha after emergence and after both the first and second harvests. The 1st harvest under schedules A, B and C was on 10, 15 and 22 July followed by the 2nd harvest in 28, 37 and 40 days and the 3rd harvest in 30, 50 and 37 days after the 2nd harvest, respectively. The 4th harvest for schedule A was 46 days after the 3rd harvest. Mean dry matter yields ranged from 6.26 to 9.03 t/ha, total N in tissue from 2.09 to 2.99%, in vitro digestibility of dry matter from 73.3 to 76.3%, and dry matter content from 12.1 to 14.1% depending on the N rate and/or harvest schedule. Nitrate-N concentration in plant tissue was low for 40 and 80 kg/N/ha/application but reached up to 0.45% for the 120 kg/ha/application under harvest schedule A. Yield distribution within the season was most uniform for schedule B. A 3-harvest schedule with 80 kg/ha of applied N at seeding and after the 1st and 2nd harvests was suitable management for Promenade Westerwolds ryegrass in this region.

The effect of additive treatment of grass silage and the food additive avoparcin on the response of calves to supplementation of silage-based diets with fish meal

1988 ◽  
Vol 47 (2) ◽  
pp. 245-252 ◽  
Author(s):  
R. W. J. Steen
Keyword(s):  
Formic Acid ◽  
Dry Matter ◽  
Volatile Fatty Acids ◽  
Fish Meal ◽  
Live Weight ◽  
Food Additive ◽  
Total N ◽  
Grass Silage ◽  
Fermentation Quality

ABSTRACTTwo experiments have been carried out to examine the effects of the fermentation quality of grass silage and the inclusion of avoparcin in the diet on the response in the performance of calves to supplementation of silage-based diets with fish meal. The eight treatments used in each experiment consisted of untreated and formic acid-treated (2·5 1/t) silages offered ad libitum and supplemented with either barley (B) or a barley/fish meal (BF) concentrate (200 g fish meal per kg), without or with 150 mg avoparcin per head daily in a 2 × 2 × 2 factorial design. All animals received 1·25 and 1·0 kg concentrates per head daily in experiments 1 and 2 respectively. In each experiment, the diets were offered to 40 castrated male cattle which were initially 126 and 110 kg live weight in experiments 1 and 2 respectively. On average over the two experiments the untreated and formic acid-treated silages contained 24·8 and 24·5 g nitrogen (N) per kg dry matter (DM); 475 and 571 g protein N per kg total N; 76 and 62 g ammonia-N per kg total N and 45-9 and 27·5 g volatile fatty acids per kg DM respectively. Silage DM intakes for the untreated silages supplemented with B and BF and the acid-treated silages supplemented with B and BF without avoparcin and for the untreated silages supplemented with B and BF and the acid-treated silages supplemented with B and BF with avoparcin were 3·0, 3·2, 3·2, 3·0, 2·9, 3·0, 3·0 and 3·2 (s.e. 0·16) kg/day respectively. Live-weight gains for the corresponding treatments were 0·97, 1·12, 0·98, 1·01, 1·00, 1·07, 1·10 and 1·13 (s.e. 0·032) kg/day respectively. It is concluded that the inclusion of fish meal in diets based on well preserved, grass silage and barley did not affect intake and produced a small response (70 g/day) in the live-weight gain of calves. The inclusion of avoparcin in the diet did not significantly affect the response to fish meal.

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