scholarly journals The nitrate concentration of domestic vegetables on Helsinki market in summer and autumn 1984

1987 ◽  
Vol 59 (5) ◽  
pp. 425-430
Author(s):  
Seija Ahonen ◽  
Iris Kuokkanen ◽  
Pirjo-Liisa Penttilä
Keyword(s):  
Brassica Oleracea ◽  
Brassica Rapa ◽  
Chinese Cabbage ◽  
Nitrate Concentration ◽  
Fresh Weight ◽  
Wide Range ◽  
Nitrate Concentrations ◽  
The Mean ◽  
Brassica Pekinensis

Nitrate concentration of some domestic vegetables at Helsinki district market was studied during the summer and autumn months of the year 1984.The species were cabbage (Brassica oleracea var capitata), Chinese cabbage (Brassica pekinensis), kohlrabi (Brassica oleracea var gongylodes), turnip (Brassica rapa), carrot (Daucus Carola subsp. sativas) and crisphead and butter head lettuce (Lactuca saliva var. capitata). The 395 samples were analysed with an ion specific electrode. There was a wide range of nitrate concentrations within each species. The mean concentrations mg nitrates/kg of fresh weight were the following: butter head lettuce 1835, Chinese cabbage 1057, kohlrabi 1008, crisphead lettuce 964, turnip 908, cabbage 607 and carrot 264. The nitrate concentration of butter head lettuce in the autumn was more than twice as high as that in the summer, and vice versa as to cabbage samples. The nitrate concentration of carrot samples in the summer was about 40 % higher than in the autumn.

Subsurface reactivity dominates regional patterns of riverine nitrate concentration variability

2020 ◽  
Author(s):  
Andreas Musolff ◽  
Pia Ebeling ◽  
Jan H. Fleckenstein ◽  
Rohini Kumar ◽  
Rémi Dupas
Keyword(s):  
Large Scale ◽  
Nitrate Concentration ◽  
Low Flow ◽  
Flow Conditions ◽  
Regional Patterns ◽  
Low Concentration ◽  
Concentration Variance ◽  
Wide Range ◽  
Nitrate Concentrations ◽  
The Mean

<p>The mean surface water concentration and the concentration variance of nutrients are major water quality characteristics of catchments that directly relates to exported nutrient loads and ecosystems functioning. The mean concentration reflects nutrient input, discharge (Q) and retention within different compartments of the catchment. The concentration variability defines the export regime of a certain solute and can be characterized by the ratio of CV<sub>C</sub> and CV<sub>Q</sub> and the slope <em>b </em>of the logC-logQ relationship. Recent explorative modelling studies argue that the export regime is shaped by spatial variance of the solute source in the catchment and by the subsurface reactivity (Musolff et al. 2017, Zhi et al. 2019). Here, we seek large scale evidence of this hypothesis by analyzing nitrate concentration and discharge (C-Q) time series in more than 1400 catchments across France and Germany. We found a consistent relationship between mean nitrate concentrations and the fraction of cultivated area within the catchments pointing to agriculture as the dominant nitrate source. The upper boundary of this relationship follows an exponential function with catchments showing mean nitrate concentrations around this envelope function being characterized by chemostatic export regimes with low concentration variance and slope <em>b</em> near zero. In contrast, catchments deviating from this relationship i.e. with lower than expected mean nitrate concentrations are characterized by higher concentration variance and steep, positive logC-logQ slopes. We argue, that subsurface retention is the major control of this behavior: i.e., effective denitrification decreases groundwater nitrate concentration. This was mainly observed in catchments with sedimentary aquifers and low topographic slopes. Here, old water components in the catchment storage that dominate discharge under low flow conditions are low in nitrate. Under high flow conditions, young water components high in nitrate concentrations are activated. Catchments without effective nitrate retention are characterized by a low concentration gradient between younger and older water components. The observed relationship between the fraction of cultivated areas, mean nitrate concentration and export regime was found to be surprisingly consistent across the wide range of hydroclimatic conditions, geology and topography. In consequence, steeply positive logC-logQ slopes can be used as indicators of effective subsurface reactivity. Future work will further elucidate the catchment characteristics that favor effective denitrification.</p><p>References</p><p>Musolff, A., Fleckenstein, J.H., Rao, P.S.C., Jawitz, J.W., 2017. Emergent archetype patterns of coupled hydrologic and biogeochemical responses in catchments. Geophys Res Lett, 44(9): 4143-4151. DOI:10.1002/2017GL072630</p><p>Zhi, W., Li, L. Dong, W.M., Brown, W., Kaye, J., Steefel, C., Williams, K.H., 2019. Distinct Source Water Chemistry Shapes Contrasting Concentration-Discharge Patterns. Water Resour Res, 55(5): 4233-4251. DOI:10.1029/2018wr024257</p>

scholarly journals Effect on nitrate concentration in stream water of agricultural practices in small catchments in Brittany: I. Annual nitrogen budgets

2002 ◽  
Vol 6 (3) ◽  
pp. 497-506 ◽  
Author(s):  
L. Ruiz ◽  
S. Abiven ◽  
P. Durand ◽  
C. Martin ◽  
F. Vertès ◽  
...  
Keyword(s):  
Land Use ◽  
Nitrate Concentration ◽  
Stream Water ◽  
Agricultural Practices ◽  
Climatic Conditions ◽  
Nitrogen Budgets ◽  
Annual Variations ◽  
Nitrate Concentrations ◽  
The Mean ◽  
Small Catchments

Abstract. The hydrological and biogeochemical monitoring of catchments has become a common approach for studying the effect of the evolution of agricultural practices on water resources. In numerous studies, the catchment is used as a "mega-lysimeter" to calculate annual input-output budgets. However, the literature reflects two opposite interpretations of the trends of nitrate concentration in streamwater. For some authors, essentially in applied studies, the mean residence time of leached nitrate in shallow groundwater systems is much less than one year and river loads reflect annual land use while for others, nitrate is essentially transport limited, independent of soil nitrate supply in the short term and annual variations reflect changes in climatic conditions. This study tests the effect of agricultural land-use changes on inter-annual nitrate trends on stream water of six small adjacent catchments from 0.10 to 0.57 km2 in area, on granite bedrock, at Kerbernez, in Western Brittany (France). Nitrate concentrations and loads in streamwater have been monitored for nine years (1992 to 2000) at the outlet of the catchments. An extensive survey of agricultural practices from 1993 to 1999 allowed assessment of the nitrogen available for leaching through nitrogen budgets. For such small catchments, year-to-year variations of nitrate leaching can be very important, even when considering the 'memory effect' of soil, while nitrate concentrations in streamwater appear relatively steady. No correlation was found between the calculated mean nitrate concentration of drainage water and the mean annual concentration in streams, which can even exhibit opposite trends in inter-annual variations. The climatic conditions do not affect the mean concentration in streamwater significantly. These results suggest that groundwater plays an important role in the control of streamwater nitrate concentration. Keywords: nitrate, diffuse pollution, agricultural catchment, nitrogen budget, leaching, Kerbernez catchments

scholarly journals A SEASON EXTENSION TECHNIQUE FOR COOL SEASON VEGETABLES USING POLY TUNNELS AND ROW COVERS

HortScience ◽  
1993 ◽  
Vol 28 (4) ◽  
pp. 269E-269
Author(s):  
Gloria McIntosh ◽  
Gerald Klingaman
Keyword(s):  
Brassica Oleracea ◽  
Brassica Rapa ◽  
Spinacia Oleracea ◽  
Fresh Weight ◽  
Cool Season ◽  
Pak Choi ◽  
Mild Winter ◽  
Row Covers ◽  
Additional Protection ◽  
Season Extension

Spunbonded polyester or polystyrene row covers were used as additional cold protection for spinach (Spinacia oleracea), kale (Brassica oleracea), pak choi (Brassica rapa) and P-types of lettuce (Lactuca savita) grown in ground beds under unheated polyethylene tunnels during the fall and winter of 1991 and 1992 in climatic zone 6. Temperatures inside poly tunnels averaged 2.4C warmer than outside. Average temperatures were 1.9C warmer than control under polystyrene and 1.5C warmer under spunbonded polyester. Average hourly temperatures showed both row covers offered significantly more cold protection than the greenhouse covering alone; but the two row covers offered similar protection from the cold. Row covers did not result in fresh weight differences in most of the species tested, except kale which had greater fresh weight in control. It may be concluded that during a similar mild winter, these cool season vegetables could be grown under unheated polyethylene tunnels with no additional protection necessary. When temperatures are lower, row covers could provide the protection required to produce these crops.

Characterization of interspecific hybrids between Chinese cabbage (Brassica rapa) and red cabbage (Brassica oleracea)

2019 ◽  
Vol 250 ◽  
pp. 33-37 ◽  
Author(s):  
Yunxiao Wei ◽  
Fei Li ◽  
Shujiang Zhang ◽  
Shifan Zhang ◽  
Hui Zhang ◽  
...  
Keyword(s):  
Brassica Oleracea ◽  
Brassica Rapa ◽  
Chinese Cabbage ◽  
Interspecific Hybrids ◽  
Red Cabbage

scholarly journals NITROGEN AND BORON RATES FOR SELECTED BRASSICA GROWN ON EAST TEXAS ACID, SANDY SOIL

HortScience ◽  
1990 ◽  
Vol 25 (8) ◽  
pp. 858e-858
Author(s):  
J. V. Davis ◽  
D. R. Earhart ◽  
A. T. Leonard ◽  
V. A. Haby
Keyword(s):  
Brassica Oleracea ◽  
Brassica Rapa ◽  
Sandy Soil ◽  
Chinese Cabbage ◽  
Total Yield ◽  
Head Size ◽  
East Texas ◽  
Randomized Design ◽  
Brassica Spp ◽  
Head Weight

The potential for east Texas to produce Brassica that could compete favorably with the import market exists. This study was conducted to establish optimum nitrogen and boron rates for 4 Brassica spp. grown on highly leachable east Texas soil, a Bowie series (fine-loamy, siliceous, thermic, Plinthic Paleudult). Broccoli (Brassica oleracea L. Italica, var. Green Comet), cauliflower (Brassica oleracea L. Botrytis var. White Contessa), Chinese cabbage (Brassica rapa L. Pekinensis var. Monument), and Chinese mustard (Brassica rapa L. Chinensis var. What-A-Joy) were field grown using 5 rates of N (0, 50, 100, 150, and 200 kg·ha-1) interacted with 3 rates of B (0, 1.25 and 2.5 kg·ha-1) in a complete randomized design with 3 reps. Harvested broccoli heads increased average head weight (HW), average head size (HS), and total yield (Y) for each increase of N. Cauliflower HW, HS, and Y increased up to 150 kg N ha-1. B supplementation did not statistically affect HW, HS, and Y of broccoli or cauliflower. Chinese cabbage Y increased up to 150 kg N ha-1 and produced less Y at 200 kg N ha-1 than at 50 kg N ha-1. Chinese mustard Y increased 50% for the 50 (kg·ha-1) N over no added N with additional N producing statistically equal Y. B at 1.25 (kg·ha-1) significantly increased cabbage Y, but had no effect on mustard Y.

scholarly journals Antecedent flow conditions and nitrate concentrations in the Mississippi River basin

2014 ◽  
Vol 18 (3) ◽  
pp. 967-979 ◽  
Author(s):  
J. C. Murphy ◽  
R. M. Hirsch ◽  
L. A. Sprague
Keyword(s):  
River Basin ◽  
Mississippi River ◽  
Nitrate Concentration ◽  
Regional Scale ◽  
Mississippi River Basin ◽  
Flow Conditions ◽  
Daily Streamflow ◽  
Nitrate Concentrations ◽  
High Flows ◽  
The Mean

Abstract. The relationship between antecedent flow conditions and nitrate concentrations was explored at eight sites in the 2.9 million square kilometers (km2) Mississippi River basin, USA. Antecedent flow conditions were quantified as the ratio between the mean daily flow of the previous year and the mean daily flow from the period of record (Qratio), and the Qratio was statistically related to nitrate anomalies (the unexplained variability in nitrate concentration after filtering out season, long-term trend, and contemporaneous flow effects) at each site. Nitrate anomaly and Qratio were negatively related at three of the four major tributary sites and upstream in the Mississippi River, indicating that when mean daily streamflow during the previous year was lower than average, nitrate concentrations were higher than expected. The strength of these relationships increased when data were subdivided by contemporaneous flow conditions. Five of the eight sites had significant negative relationships (p ≤ 0.05) at high or moderately high contemporaneous flows, suggesting nitrate that accumulates in these basins during a drought is flushed during subsequent high flows. At half of the sites, when mean daily flow during the previous year was 50 percent lower than average, nitrate concentration can be from 9 to 27 percent higher than nitrate concentrations that follow a year with average mean daily flow. Conversely, nitrate concentration can be from 8 to 21 percent lower than expected when flow during the previous year was 50 percent higher than average. Previously documented for small, relatively homogenous basins, our results suggest that relationships between antecedent flows and nitrate concentrations are also observable at a regional scale. Relationships were not observed (using all contemporaneous flow data together) for basins larger than 1 million km2, suggesting that above this limit the overall size and diversity within these basins may necessitate the use of more complicated statistical approaches or that there may be no discernible basin-wide relationship with antecedent flow. The relationships between nitrate concentration and Qratio identified in this study serve as the basis for future studies that can better define specific hydrologic processes occurring during and after a drought (or high flow period) which influence nitrate concentration, such as the duration or magnitude of low flows, and the timing of low and high flows.

scholarly journals Antecedent flow conditions and nitrate concentrations in the Mississippi River Basin

2013 ◽  
Vol 10 (9) ◽  
pp. 11451-11484 ◽  
Author(s):  
J. C. Murphy ◽  
R. M. Hirsch ◽  
L. A. Sprague
Keyword(s):  
River Basin ◽  
Mississippi River ◽  
Nitrate Concentration ◽  
Mississippi River Basin ◽  
Storm Events ◽  
Flow Conditions ◽  
Continental Scale ◽  
Antecedent Moisture ◽  
Nitrate Concentrations ◽  
The Mean

Abstract. The influence of antecedent flow conditions on nitrate concentrations was explored at eight sites in the Mississippi River Basin, USA. Antecedent moisture conditions have been shown to influence nutrient export from small, relatively homogenous basins, but this influence has not been observed at a regional or continental scale. Antecedent flow conditions were quantified as the ratio between the mean daily flow of the previous year and the mean daily flow from the period of record (Q ratio), and the Q ratio was statistically related to nitrate anomalies (the unexplained variability in nitrate concentration after filtering out season, long-term trend, and contemporaneous flow effects) at each site. Nitrate anomaly and Q ratio were negatively related at three of the four major tributary sites and upstream in the Mississippi River, indicating that when the previous year was drier than average, at these sites, nitrate concentrations were higher than expected. The strength of these relationships increased when data were subdivided by contemporaneous flow conditions. Five of the eight sites had significant negative relationships (p ≤ 0.05) at high or moderately high contemporaneous flows, suggesting nitrate that accumulates in these basins during a drought is flushed during subsequent storm events. At half of the sites, when flow during the previous year was 50% drier than average, nitrate concentration can be from 9 and 27% higher than nitrate concentrations that follow a year with average daily flow. Conversely, nitrate concentration can be from 8 and 21% lower than expected when the previous year was 50% wetter than average. These relationships between nitrate concentration and Q ratio serve as the basis for future studies that can better define specific hydrologic processes occurring during and after a drought, which influence nitrate concentration, such as the duration or magnitude of low flows, and the timing of low and high flows.

scholarly journals Ozone fumigation increases the abundance of nutrients in Brassica vegetables: broccoli (Brassica oleracea var. italica) and Chinese cabbage (Brassica pekinensis)

2014 ◽  
Vol 240 (2) ◽  
pp. 459-462 ◽  
Author(s):  
Piotr Rozpądek ◽  
Michał Nosek ◽  
Irenusz Ślesak ◽  
Edward Kunicki ◽  
Michał Dziurka ◽  
...  
Keyword(s):  
Brassica Oleracea ◽  
Chinese Cabbage ◽  
Brassica Vegetables ◽  
Brassica Pekinensis

A Comparison of Physiological Demand between Self-Propelled and Motorized Treadmill Exercise

2018 ◽  
Vol 7 (4) ◽  
pp. 13-21
Author(s):  
Todd Backes ◽  
Charlene Takacs
Keyword(s):  
Respiratory Exchange Ratio ◽  
Treadmill Exercise ◽  
Cardiopulmonary Exercise Testing ◽  
Mean Value ◽  
The Self ◽  
Mixing Chamber ◽  
Wide Range ◽  
The Subject ◽  
The Mean ◽  
Computer Controlled

There are a wide range of options for individuals to choose from in order to engage in aerobic exercise; from outdoor running to computer controlled and self-propelled treadmills. Recently, self-propelled treadmills have increased in popularity and provide an alternative to a motorized treadmill. Twenty subjects (10 men, 10 women) ranging in age from 19-23 with a mean of 20.4 ± 0.8 SD were participants in this study. The subjects visited the laboratory on three occasions. The purpose of the first visit was to familiarize the subject with the self-propelled treadmill (Woodway Curve 3.0). The second visit, subjects were instructed to run on the self-propelled treadmill for 3km at a self-determined pace. Speed data were collected directly from the self-propelled treadmill. The third visit used speed data collected during the self-propelled treadmill run to create an identically paced 3km run for the subjects to perform on a motorized treadmill (COSMED T150). During both the second and third visit, oxygen consumption (VO2) and respiratory exchange ratio (R) data were collected with COSMED’s Quark cardiopulmonary exercise testing (CPET) metabolic mixing chamber system. The VO2 mean value for the self-propelled treadmill (44.90 ± 1.65 SE ml/kg/min) was significantly greater than the motorized treadmill (34.38 ± 1.39 SE ml/kg/min). The mean R value for the self-propelled treadmill (0.91 ± 0.01 SE) was significantly greater than the motorized treadmill (0.86 ± 0.01 SE). Our study demonstrated that a 3km run on a self-propelled treadmill does elicit a greater physiological response than a 3km run at on a standard motorized treadmill. Self-propelled treadmills provide a mode of exercise that offers increased training loads and should be considered as an alternative to motorized treadmills.

The way of value of Correlation of genomic DNA microsatellite loci and live weight of Chukchi reindeer

2020 ◽  
pp. 27-32
Author(s):  
V. Dodokhov ◽  
N. Pavlova ◽  
T. Rumyantseva ◽  
L. Kalashnikova
Keyword(s):  
Microsatellite Markers ◽  
Agricultural Production ◽  
Live Weight ◽  
Biodiversity Loss ◽  
Tribal Community ◽  
High Germination ◽  
Wide Range ◽  
The Mean ◽  
High Level ◽  
Dna Microsatellite

The article presents the genetic characteristic of the Chukchi reindeer breed. The object of the study was of the Chukchi reindeer. In recent years, the number of reindeer of the Chukchi breed has declined sharply. Reduced reindeer numbers could lead to biodiversity loss. The Chukchi breed of deer has good meat qualities, has high germination viability and is adapted in adverse tundra conditions of Yakutia. Herding of the Chukchi breed of deer in Yakutia are engaged only in the Nizhnekolymsky district. There are four generic communities and the largest of which is the agricultural production cooperative of nomadic tribal community «Turvaurgin», which was chosen to assess the genetic processes of breed using microsatellite markers: Rt6, BMS1788, Rt 30, Rt1, Rt9, FCB193, Rt7, BMS745, C 143, Rt24, OheQ, C217, C32, NVHRT16, T40, C276. It was found that microsatellite markers have a wide range of alleles and generally have a high informative value for identifying of genetic differences between animals and groups of animal. The number of identified alleles is one of the indicators of the genetic diversity of the population. The total number of detected alleles was 127. The Chukchi breed of deer is characterized by a high level of heterozygosity, and the random crossing system prevails over inbreeding in the population. On average, there were 7.9 alleles (Na) per locus, and the mean number of effective alleles (Ne) was 4.1. The index of fixation averaged 0.001. The polymorphism index (PIC) ranged from 0.217 to 0.946, with an average of 0.695.

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