scholarly journals A comparison of animal output and nitrogen leaching losses recorded from drained fertilized grass and grass/clover pasture

1997 ◽  
Vol 129 (3) ◽  
pp. 315-323 ◽  
Author(s):  
K. C. TYSON ◽  
D. SCHOLEFIELD ◽  
S. C. JARVIS ◽  
A. C. STONE
Keyword(s):  
Previous History ◽  
Extended Period ◽  
Drainage Water ◽  
Nitrogen Leaching ◽  
Early Spring ◽  
The European Union ◽  
Nitrate N ◽  
Average Annual Loss ◽  
Highly Correlated ◽  
Clover Pasture

Annual liveweight gain of beef cattle (steers) grazing grass pasture fertilized with 200 kg N/ha was compared over a period of 7 years (1989–95) with that of steers grazing grass/white clover pasture given no artificial N fertilizer at North Wyke, Devon, UK. Nitrogen lost by leaching over the ensuing winter drainage periods was monitored from both pastures. Nitrogen leaching loss from the fertilized pasture over an extended period of 13 years (1983–95) is also reported.The average annual liveweight gain of the steers grazing the grass/clover pasture (0·81 t/ha) was 19% lower than that of the steers grazing the N-fertilized grass pasture (1·00 t/ha). The average annual loss of nitrate-N by leaching in winter drainage from the grass/clover pasture (13 kg/ha) was only 26% of that recorded from the fertilized grass (50 kg/ha). A possible reason for this difference may arise from the previous history of the grass/clover pasture which had been ploughed in 1982, causing a flush of N mineralization and consequently greater immobilization of N in the soil in subsequent years.Losses of N each winter by leaching measured over a 13-year period from the fertilized grass were highly correlated (P<0·001) with the preceding summer's soil moisture deficit, with the highest losses following dry summers. The nitrate-N concentration in the drainage water exceeded the European Union limit in drinking water (11·3 mg/l) in the initial 25 mm of drainage during 11 of the 13 autumns. The average loss of N each winter (53 kg/ha) was equivalent to 26% of the fertilizer-N applied annually. Immediate losses of N by leaching of fertilizer applied in early spring and throughout one very wet summer (1993) were minimal.

Impact of Fertigation versus Controlled-release Fertilizer Formulations on Nitrate Concentrations in Nursery Drainage Water

2011 ◽  
Vol 21 (2) ◽  
pp. 176-180 ◽  
Author(s):  
P. Chris Wilson ◽  
Joseph P. Albano
Keyword(s):  
Water Quality ◽  
Controlled Release ◽  
Drainage Water ◽  
Plant Production ◽  
Fertilization Program ◽  
Median Concentration ◽  
Nitrate N ◽  
Production Area ◽  
Foliage Plant ◽  
Production Areas

Nitrate-nitrogen (N) losses in surface drainage and runoff water from ornamental plant production areas can be considerable. In N-limited watersheds, discharge of N from production areas can have negative impacts on nontarget aquatic systems. This study monitored nitrate-N concentrations in production area drainage water originating from a foliage plant production area. Concentrations in drainage water were monitored during the transition from 100% reliance on fertigation using urea and nitrate-based soluble formulations (SF) to a nitrate-based controlled-release formulation (CRF). During the SF use period, nitrate-N concentrations ranged from 0.5 to 322.0 mg·L−1 with a median concentration of 31.2 mg·L−1. Conversely, nitrate-N concentrations during the controlled-release fertilization program ranged from 0 to 147.9 mg·L−1 with a median concentration of 0.9 mg·L−1. This project demonstrates that nitrate-N concentrations in drainage water during the CRF program were reduced by 94% to 97% at the 10th through 95th percentiles relative to the SF fertilization program. Nitrate-N concentrations in drainage water from foliage plant production areas can be reduced by using CRF fertilizer formulations relative to SF formulations/fertigation. Similar results should be expected for other similar containerized crops. Managers located within N-limited watersheds facing N water quality regulations should consider the use of CRF fertilizer formulations as a potential tool (in addition to appropriate application rates and irrigation management) for reducing production impacts on water quality.

scholarly journals Nutrient losses in drainage and surface runoff from a cattle-grazed pasture in Southland

2000 ◽  
pp. 99-104 ◽  
Author(s):  
R.M. Monaghan ◽  
R.J. Paton ◽  
L.C. Smith ◽  
C. Binet
Keyword(s):  
Surface Runoff ◽  
Dairy Herd ◽  
Drainage Water ◽  
Primary Objective ◽  
Stocking Rate ◽  
N Losses ◽  
Pasture Production ◽  
Leaching Losses ◽  
Drinking Water Standard ◽  
Nitrate N

In response to local concerns about the expanding Southland dairy herd, a 4-year study was initiated in 1995 with the primary objective of quantifying nitrate-N losses to waterways from intensively grazed cattle pastures. Treatments were annual N fertiliser inputs of 0, 100, 200 or 400 kg N/ha. Stocking rate was set according to the pasture production on each of these four treatments, and over the 4 years of study ranged between the equivalent of 2.0 cows/ha for the 0N treatment, to 3.0 cows/ha for the treatment receiving 400 kg N/ ha/year. Mean annual losses of nitrate-N in drainage were 30, 34, 46 and 56 kg N/ha for the 0, 100, 200 and 400 kg N/ha/year treatments, respectively. Corresponding mean nitrate-N concentrations in drainage waters were 8.3, 9.2, 12.5 and 15.4 mg/ l, respectively. Very little direct leaching of fertiliser N was observed, even for drainage events in early spring, shortly after urea fertiliser application. The increased nitrate-N losses at higher rates of N fertiliser addition were instead owing to the indirect effect of increasing returns of urine and dung N to pasture. In Years 2 and 3, leaching losses of Ca, Mg, K, Na and sulphate-S averaged 61, 9, 11, 28 and 17 kg/ha/year, respectively, in the 0N fertiliser treatment. Increasing fertiliser N inputs significantly increased calcium and, to a lesser extent, potassium leaching losses but had no effect on losses of other plant nutrients. Surface runoff losses of Total-P, nitrate-N and ammonium- N were less than 0.5 kg/ha/year. For this well-drained Fleming soil, surface runoff was a relatively minor contributor of N to surface water, even for plots receiving high rates of fertiliser N and at a stocking rate of 3.0 cows/ha. Extrapolating these results to a 'typical' dairy pasture in Eastern Southland would suggest that the safe upper limit for annual fertiliser N additions to this site to achieve nitrate in drainage water below the drinking water standard is approximately 170 kg N/ha. Although losses of Ca in drainage were large, returns of this nutrient in maintenance applications of superphosphate-based products and lime should ensure Ca deficiencies are avoided in Southland dairy pastures. Keywords: cation-anion balances, dairy, N fertiliser, nitrate leaching, surface runoff, Southland

The effect of seeding rate and nitrogen fertilizer on the winter production of irrigated sod-sown oats at Badgery's Creek

1966 ◽  
Vol 6 (20) ◽  
pp. 42 ◽  
Author(s):  
FC Crofts
Keyword(s):  
Nitrogen Fertilizer ◽  
Dry Matter ◽  
Lower Cost ◽  
Early Spring ◽  
Nitrogen Fertilizers ◽  
Critical Factors ◽  
Forage Production ◽  
Seeding Rate ◽  
Spray Irrigation ◽  
Clover Pasture

Under supplementary spray irrigation at Badgery's Creek, N.S.W., it has been possible to increase the late autumn, winter, and early spring production of a clover dominant ryegrass-clover pasture by more than 3,000 lb of dry matter an acre by sod-seeding oats with nitrogen fertilizers. The oat seeding rate and the amount of nitrogen fertilizer applied at seeding are critical factors in determining the amount of additional winter forage obtained. At this stage it appears that the sod-seeding of oats at four bushels an acre with about 90 lb of nitrogen an acre in early autumn will greatly increase winter forage production under irrigation at a much lower cost than that associated with hand-feeding.

The effect of nitrogen fertilizer on the seasonal production of an irrigated ryegrass-clover pasture at Badgery's Creek

1965 ◽  
Vol 5 (19) ◽  
pp. 417 ◽  
Author(s):  
FC Crofts
Keyword(s):  
Nitrogen Fertilizer ◽  
Crude Protein ◽  
Dry Matter ◽  
Early Spring ◽  
Late Spring ◽  
Summer Period ◽  
Fertilizer Nitrogen ◽  
Clover Pasture

Nitrogen fertilizer applied as sulphate of ammonia at 23 to 92 pounds of nitrogen an acre in early spring made forage available for grazing six weeks earlier and returned 19 to 22 pounds of additional dry matter (with 14 to 19 per cent crude protein) for each pound of fertilizer nitrogen applied. However, the responses to nitrogen fertilizer became progressively less over the late spring and summer period and the responses in the autumn, when additional forage is urgently needed for winter reserves, were relatively small.

scholarly journals Inter-comparison of IASI and AATSR over an extended period

2015 ◽  
Vol 8 (9) ◽  
pp. 9785-9821
Author(s):  
M. Bali ◽  
J. Mittaz ◽  
E. Maturi ◽  
M. Goldberg
Keyword(s):  
Extended Period ◽  
Large Temperature ◽  
Calibration System ◽  
Temperature Dependent ◽  
Design Specification ◽  
Temperature Range ◽  
Global Space ◽  
Critical Issues ◽  
Highly Correlated ◽  
Stability And Accuracy

Abstract. The launch of ENVISAT in 2002 and the launch of MetTop-A in 2006 put two highly accurate instruments in space to measure Top of Atmosphere (TOA) radiances. These instruments are the AATSR and IASI. While the AATSR, by design is a climate accurate (i.e. accuracy within 0.1 K and stability within 0.05 K dec−1) instrument, the IASI is a hyperspectral instrument that has a stated accuracy of within 0.5 K. This accuracy and stability are used in producing climate CDR's from these instruments and also aids in using these instruments as benchmarks for inter-comparison studies that aim at measuring stability and accuracy of instruments that are concurrently flying with them. The GSICS (Global Space Based Inter-Calibration System) has extensively exploited the IASI by comparing its measurements with Polar as well as Geostationary satellite instruments and measuring the in-orbit stability and accuracy of these instruments. More recent re-calibration efforts, such as the NOAA CDR project that is aimed at recalibrating the AVHRR uses the IASI and the AATSR as references. However to trust the recalibrated radiances it is vital that the in-orbit accuracy of the reference sources is known and critical issues such as scan angle dependence, and temporal variation of the accuracy are fully evaluated across a large temperature range (200–300 K). In order to better understand the accuracy and asses the trustworthiness of these references we present here a comprehensive analysis of the AATSR–IASI bias derived from their collocated pixels, over the period January 2008 through March 2011. Our analysis indicates that generally the AATSR (Nadir View) and IASI can act as good reference instruments and IASI is much more accurate than its design specification. In fact, taking into account a small bias the AATSR–IASI bias is close to the AATSR pre-launch bias implying that IASI can get close to pre-launch levels of accuracy. We also examine temperature dependent bias in the AATSR at low (< 240 K) temperatures which seems to appear after orbit was lowered of the ENVISAT satellite and its inclination control was discontinued. In addition, a very small scan angular dependence of AATSR–IASI bias indicates that the AVHRR has a scan angle dependent bias. We also examine the bias problem with the 12 μm channel of the AATSR in detail. We show that this bias not only has a temperature dependence (it grows up to 0.4 K at low temperatures) but also has a seasonal dependence in the SST (265–300 K) temperature range and is highly correlated to instrument temperature in the cold temperature range. We then discuss a possible method to correct the 11 and the 12 μm bias so as to use the corrected radiances for re-calibration of AVHRR.

scholarly journals Quantifying heterogeneous transport of a tracer and a degradable contaminant in the field, under two infiltration rates

2012 ◽  
Vol 9 (4) ◽  
pp. 4827-4868
Author(s):  
D. Schotanus ◽  
M. J. van der Ploeg ◽  
S. E. A. T. M. van der Zee
Keyword(s):  
Field Experiments ◽  
Preferential Flow ◽  
Infiltration Rate ◽  
Soil Heterogeneity ◽  
Early Spring ◽  
Early Summer ◽  
Flow Paths ◽  
Infiltration Rates ◽  
Preferential Flow Paths ◽  
Highly Correlated

Abstract. To examine the persistence of preferential flow paths in a field soil, and to compare the leaching of a degradable contaminant with the leaching of a non-degradable tracer, we did two field experiments, using a multicompartment sampler. The first experiment was done during the snowmelt period in early spring, characterized by high infiltration fluxes from snowmelt. The second experiment was done in early summer with irrigation to mimic homogeneous rainfall. In the second experiment, the soil was warmer and degradation of the degradable contaminant was observed. For both experiments, the highest tracer concentrations were found in the same area of the sampler, but the leached tracer masses of the individual locations were not highly correlated. Thus, the preferential flow paths were stable between seasons. With a lower infiltration rate, in the second experiment, more isolated peaks in the drainage and the leached masses were found than in the first experiment. Therefore it is concluded that the soil heterogeneity is mainly caused by local differences in the soil hydraulic properties, and not by macropores. With higher infiltration rates, the clustering of high and low leaching cells was higher. The leached masses of the degradable contaminant were lower than the leached masses of the non-degradable tracer, but the masses were highly correlated. The first-order degradation rate was 0.02 d−1. The dispersivity varied between 1.9 and 7.1 cm. Soil heterogeneity is the main reason for the heterogeneous water flow and solute transport in this soil. Heterogeneous melting of snow does not influence the heterogeneous flow in the soil much at this scale.

scholarly journals Bamboo Water Transport Assessed with Deuterium Tracing

Forests ◽  
2019 ◽  
Vol 10 (8) ◽  
pp. 623 ◽  
Author(s):  
Tingting Mei ◽  
Dongming Fang ◽  
Alexander Röll ◽  
Dirk Hölscher
Keyword(s):  
Water Transport ◽  
Water Use ◽  
Extended Period ◽  
Sap Flux ◽  
Short Term ◽  
The Difference ◽  
Highly Correlated ◽  
Species Specific ◽  
Water Use Rates ◽  
Deuterium Tracing

Bamboo water transport comprises the pathway rhizomes-culms-leaves as well as transfer among culms via connected rhizomes. We assessed bamboo water transport in three big clumpy bamboo species by deuterium tracing. The tracer was injected into the base of established culms, and water samples were collected from leaves of the labeled culms and from neighboring culms. From the base of labeled culms to their leaves, the average tracer arrival time across species was 1.2 days, maximum tracer concentration was reached after 1.8 days, and the tracer residence time was 5.6 days. Sap velocities were high (13.9 m d−1). Daily culm water use rates estimated by the tracer method versus rates measured by a calibrated sap flux method were highly correlated (R2 = 0.94), but the tracer estimates were about 70% higher. Elevated deuterium concentrations in studied neighbor culms point to deuterium transfer among culms, which may explain the difference in culm water use estimates. We found no differences in deuterium concentrations between neighbor-established and neighbor freshly sprouted culms of a given species. In two species, elevated concentrations in both neighbor-established and neighbor freshly sprouted culms were observed over an extended period. An applied mixing model suggests that five neighbor culms received labeled water. In contrast, for the third species, elevated concentrations in neighbor culms were only observed at the earliest sampling date after labeling. This could indicate that there was only short-term transfer and that the tracer was distributed more widely across the rhizome network. In conclusion, our deuterium tracing experiments point to water transfer among culms, but with species-specific differences.

scholarly journals Spawning strategies in cypriniform fishes in a lowland river invaded by non-indigenous European barbel Barbus barbus

Hydrobiologia ◽  
2020 ◽  
Vol 847 (19) ◽  
pp. 4031-4047
Author(s):  
Catherine Gutmann Roberts ◽  
J. Robert Britton
Keyword(s):  
Extended Period ◽  
Early Spring ◽  
Early Summer ◽  
Lowland River ◽  
Growth Season ◽  
Stochastic Mortality ◽  
Multiple Spawning ◽  
Barbus Barbus ◽  
Common Strategy ◽  
Spawning Periods

Abstract Spawning strategies of lowland river fishes include single spawning, where reproduction generally occurs in early spring to provide 0+ fish with an extended growth season through the summer, but with a high risk of stochastic mortality events occurring, such as early summer floods. This risk can be reduced by multiple or protracted spawning strategies, where 0+ fish are produced over an extended period, often into mid-summer, but with the trade-off being a shorter growth season. The spawning strategies of cypriniform fish were explored in the River Teme, a spate river in Western England, which has non-indigenous European barbel Barbus barbus present. Sampling 0+ fish in spring and summer and across three spawning periods, B. barbus, chub Squalius cephalus and minnow Phoxinus phoxinus always revealed multiple spawning events, with 0+ fish of < 20 mm present in samples collected from June to August. Fish below 20 mm in August remained relatively small by the end of their growth season (October). For dace Leuciscus leuciscus, only single spawning events were evident, but with 0+ dace always being relatively large. Therefore, multiple spawning appears to be a common strategy that provides resilience in 0+ fish against stochastic mortality events in lowland rivers.

scholarly journals Spatiotemporal Evaluation of PM10 Concentrations within the Greater Athens Area, Greece. Trends, Variability and Analysis of a 19 Years Data Series

Environments ◽  
2020 ◽  
Vol 7 (10) ◽  
pp. 85
Author(s):  
Konstantinos P. Moustris ◽  
Ermioni Petraki ◽  
Kleopatra Ntourou ◽  
Georgios Priniotakis ◽  
Dimitrios Nikolopoulos
Keyword(s):  
Statistical Treatment ◽  
Extended Period ◽  
Atmospheric Environment ◽  
Data Series ◽  
The European Union ◽  
The Past ◽  
Social Events ◽  
The Impact ◽  
Athens Area ◽  
Daily Pm10

This work investigates the spatiotemporal variation of suspended particles with aerodynamic diameter less than or equal to 10 μm (PM10) during a nineteen years period. Mean daily PM10 concentrations between 2001 and 2018, from five monitoring stations within the greater Athens area (GAA) are used. The aim is to investigate the impact of the economic crisis and the actions taken by the Greek state over the past decade on the distribution of PM10 within the GAA. Seasonality, intraweek, intraday and spatial variations of the PM10 concentrations as well as trends of data, are statistically studied. The work may assist the formation of PM10 forecasting models of hourly, daily, weekly, monthly and annual horizon. Innovations are alternative ways of statistical treatment and the extended period of data, which, importantly, includes major economic and social events for the GAA. Significant decreasing trend in PM10 series concentrations at all examined stations were found. This may be due to economic and social reasons but also due to measures taken by the state so as to be harmonised with the European Directives concerning the protection of public health and the atmospheric environment of the European Union (EU) members.

Air and soil temperature limitations on photosynthesis in Engelmann spruce during summer

1987 ◽  
Vol 17 (6) ◽  
pp. 527-533 ◽  
Author(s):  
Evan H. DeLucia ◽  
William K. Smith
Keyword(s):  
Soil Temperature ◽  
Field Experiments ◽  
Growth Period ◽  
Extended Period ◽  
Early Summer ◽  
Photosynthetic Rates ◽  
Engelmann Spruce ◽  
Air Temperatures ◽  
Highly Correlated ◽  
Elevational Range

The relative importance of air and soil temperature as potential limitations to photosynthesis during summer was assessed in Engelmann spruce over its natural elevational range in southeastern Wyoming. Low photosynthetic rates measured at constant temperature, irradiance, and vapor pressure deficit were highly correlated with low minimum (night) air and soil temperature, but at different times during the early summer growth period. Substantial and irreversible reductions in photosynthesis occurred after exposure to night air temperatures of −4 to −5 °C that occurred through mid-June. After middle to late June, decreased photosynthetic rates were correlated with low soil temperature. Correlation analyses indicated that subfreezing air temperature followed by an extended period of low soil temperature were the primary limitations to photosynthesis in early summer. Additional laboratory and field experiments corroborate these field observations.

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