Establishment and production of common sainfoin (Onobrychis viciifolia Scop.) in the UK. 2. Effects of direct sowing and undersowing in spring barley on sainfoin and sainfoin-grass mixtures     

Z. Liu  G. P. F. Lane  W. P. Davies 《Grass and Forage Science》2008,63(2):242-248

The dry matter (DM) yield and herbage quality of swards of sainfoin ( Onobrychis viciifolia ), meadow fescue ( Festuca pratensis ,) and tetraploid perennial ryegrass ( Lolium perenne ) grown in monocultures and in four sainfoin:grass mixtures (0·33 sainfoin:0·66 meadow fescue, 0·66 sainfoin:0·33 meadow fescue, 0·33 sainfoin:0·66 perennial ryegrass and 0·66 sainfoin:0·33 perennial ryegrass), established by direct sowing or undersowing in spring barley, were investigated over 3 years in a field experiment in the UK. Direct sowing produced a mean yield across all species and mixtures of 1·8 t DM ha⁻¹ in the establishment year, whereas undersowing produced no measurable yield except for that of the spring barley. Undersowing reduced the yields of sainfoin and sainfoin-grass mixtures in the first full-harvest year but not in the second. The annual yield of a monoculture of sainfoin was 7·53 t DM ha⁻¹ and that of sainfoin-grass mixtures was 8·33 t DM ha⁻¹ averaged over 3 years. Both sainfoin and the sainfoin-grass mixtures had higher annual DM yields than the grass monocultures. The mixture of 0·66 sainfoin:0·33 meadow fescue gave the highest mean annual yield (9·07 t DM ha⁻¹) over the 3 years. There was a higher proportion of sainfoin maintained in mixtures with perennial ryegrass than with meadow fescue. The proportion of sainfoin in sainfoin–meadow fescue mixtures declined from 0·62 in the first year to 0·32 in the third year, whereas the proportion in sainfoin–perennial ryegrass increased from 0·48 in the first year to 0·67 in the second year and remained stable in the third year.  相似文献   

Annual cool-season legumes for forage production in mild winter areas     

Iglesias  & Lloveras 《Grass and Forage Science》1998,53(4):318-325

The forage potential of several annual winter legumes – crimson clover ( Trifolium incarnatum L.), faba beans ( Vicia faba L.), forage peas ( Pisum sativum L.), serradella ( Ornithopus sativus Brot.) and vetches ( Vicia sativa L. and Vicia villosa Roth.) – was evaluated over two growing seasons in the wet and mild winter areas of Galicia (north-west Spain) with a moderately acid soil, at the two normal harvesting dates in the region, April and May.
The results indicate that, in April, serradella and crimson clover (in the warmer location), can produce dry-matter (DM) yields of 4–5 t ha⁻¹, which is similar to other winter forages in the same area, with an average growing season of 212–237 d, corresponding to about 339–420 accumulated degree–days above 10°C (GDD₁₀). In May, mainly in the warmer location, fava beans, peas and vetches yielded on average 4·7–8·5 t ha⁻¹ DM, with an average growing season of 166–206 d but with only 233–278 GDD₁₀ units. Faba bean, with an average of 8·5 t ha⁻¹ DM in the May harvest, was the highest producing forage legume. The results also suggest that some cool-season legumes could fit into double-cropping systems based on summer crops, such as maize, because of their forage yields and nutritive value. However, in order to produce consistent DM yields, the date of sowing is crucial; they must either be sown much earlier than the dates in this study or the harvests must be delayed until the end of April.  相似文献   

Agronomic factors affecting the yield and quality of forage maize in Ireland: effect of sowing date and plastic film treatment     

G. P. Keane 《Grass and Forage Science》2002,57(1):3-10

The objectives of these studies were to examine the effects of sowing date and plastic film on the yield and quality of forage maize ( Zea mays L.) in Ireland, a marginal maize-growing area. In 1989–95, comparisons were made of maize sown through clear plastic film (PP treatment), and maize sown in the conventional manner without plastic (NP treatment), in terms of dry-matter (DM) yield and quality (cob, grain and starch contents). The PP treatment significantly increased DM yields in five years, with a mean yield increase of 3·10 t ha⁻¹. Whole-plant DM content increased (significant in four years) by a mean of 0·15; cob content increased (significant in five years) by a mean of 0·32; grain content increased (significant in all of the three years examined) by 0·75; and starch content increased from 236 to 318 g kg⁻¹ DM ( P  < 0·01) in 1995 where the plastic film treatment was used. Organic matter digestibility values were similar for both treatments in 1995. Sowing date in the April-May period had no consistent effect on DM yields, but early sowings did increase cob (significant, except in 1994), grain (significant in one (1995) of the two years tested) and starch ( P  < 0·05) contents (only tested in 1995). Sowing on 11 April 1995 through perforated plastic gave lower yields than the NP treatment sown on the same date, due to severe frost damage in early May.  相似文献   

A plate meter inadequately estimated herbage mass in a semi-arid grassland     

J. S. Fehmi  J. M. Stevens 《Grass and Forage Science》2009,64(3):322-327

A resting plate meter was tested in the laboratory and on a field site to determine its effectiveness for estimating peak herbage mass on semi-arid grasslands. In laboratory tests, data from the plate meter closely predicted the herbage mass of four perennial bunch grasses (thirteen of sixteen tests with r ² ≥ 0·90) but the closeness of the prediction varied with the pressure of the plate. Field tests took place on a southern Arizona, USA semi-arid grassland in 2005, 2006, 2007 and 2008. Twenty teams of two or three people sampled the site; five teams in each year measured eight to thirteen plate heights and clipped the vegetation beneath. Consistent with a need for yearly calibration, a significantly different ( P  <   0·05) linear relationship was detected between 3 of the 4 years which was associated with differences in average herbage mass of dry matter (DM) (1525 kg ha⁻¹ for 2005, 2093 kg ha⁻¹ for 2006, 1338 kg ha⁻¹ for 2007 and 1370 kg ha⁻¹ for 2008). Plate height poorly predicted herbage mass within years ( r ²  = 0·21, 0·51, 0·49 and 0·41 respectively) with plate heights explaining half or less of the variability in field herbage mass and having a mean prediction error of 466 kg DM ha⁻¹. The plate meter technique had limited potential for estimating peak herbage mass in semi-arid grasslands.  相似文献   

Dry-matter yield and herbage quality of a perennial ryegrass/white clover sward in a rotational grazing and cutting system     

Schils  Vellinga  & Kraak 《Grass and Forage Science》1999,54(1):19-29

The expected reduction in the use of fertilizer nitrogen (N) on grassland in the Netherlands has led to renewed interest in white clover. Therefore, the performance of a newly sown perennial ryegrass/white clover sward on clay soil was assessed during 4 consecutive years. The experiment consisted of all combinations of two defoliation systems, i.e. one or two silage cuts per year (S1, S2), spring N application rate, i.e. 0 or 50 kg ha⁻¹ year⁻¹ (N₀, N₅₀), and the management system, i.e. rotational grazing and cutting, or cutting only (RGC, CO). The overall mean white clover cover was 30%. All treatments affected white clover cover, which was 8% higher with S2 than with S1, 6% higher with N₀ than with N₅₀ and 12% higher with CO than with RGC. The overall mean annual dry-matter (DM) yield (13·1 t ha⁻¹ year⁻¹) was significantly affected only by the management system: in two relatively wetter years, the annual DM yield was 1·19 t ha⁻¹ higher with RGC than with CO, whereas there was no difference in two relatively drier years. Nitrogen application increased the DM yield in the first cut by 7·0 kg kg⁻¹ N applied, but had no significant effect on the annual DM yield. Herbage quality was not affected by the experimental treatments. The average in vitro organic matter digestibility was 0.801, and the average crude protein content was 193 g kg⁻¹ DM. With the expected reduction in the use of fertilizer N, perennial ryegrass/white clover swards should be seriously considered as an alternative option to perennial ryegrass swards on these clay soils.  相似文献   

Barley/pea mixtures as cover crops for grass re-seeds     

T. J. GILLILAND  J. JOHNSTON 《Grass and Forage Science》1992,47(1):1-7

Substantial annual fluctuations in the performance of arable silage mixtures, comprising Minerva forage pea and Goldmarker barley, were observed from ten annual sowings between 1977 and 1986, Total dry matter (DM) yield varied between 2·5 and 11·5 t ha⁻¹. Dry matter content also ranged widely from 10·3% to 20·0% and there was a large variation in the proportion of peas in the DM (0·44 to 0·90). Almost 80% of this yield variation was due to the fluctuation in pea performance and over 60% of all yield variation was related to the variation in sunshine hours and air temperature.
In 1983 and 1984 differences in seed rate of between 20 and 140 kg ha⁻¹ of Minerva and 80 and 160 kg ha⁻¹ of Goldmarker influenced the forage composition at harvest, with the pea component capable of outgrowing and suppressing the other species when sown at over 80 kg ha⁻¹. Very high yields of peas were associated with increasing stress on the undersown grass re-seed and were considered undesirable.
It was concluded that sowing rates of between 120 and 160 kg ha⁻¹ for barley and a maximum of 60 kg ha⁻¹ for peas would, in most years, provide the best compromise between attaining good arable silage yields and avoiding excessive dangers of damage of undersown grass re-seeds.  相似文献   

Long-term responses in the yield of Eastern Gamagrass [Tripsacum dactyloides (L.) L.] to nitrogen fertilizer under two harvest regimes in the United States     

J. L. Moyer  D. W. Sweeney 《Grass and Forage Science》2008,63(3):390-397

Eastern Gamagrass [ Tripsacum dactyloides (L.) L.] is a perennial C₄ grass with potentially high productivity. Intensive management through the application of nitrogen (N) fertilizer and frequency of cutting, however, may be required to maximize its potential for forage production. This study determined the long-term and residual responses of Eastern Gamagrass in terms of dry matter (DM) yield and tiller density to three annual application rates (0, 50 or 100 kg ha⁻¹) of a N-fertilizer solution applied by broadcasting or knife placement for 5 out of the 10 years of the study, and harvested using one-cut or two-cut regimes. Application of N-fertilizer increased total DM yield in the 5 years of N applications by 0·44 with the first increment of 50 kg N ha⁻¹, and by an additional 0·15 with the next increment of 50 kg N ha⁻¹. In the first year that directly followed N-fertilizer applications, DM yield was 0·175 higher than the no fertilizer treatment when 50 kg ha⁻¹ had been previously applied and a further 0·16 higher when 100 kg ha⁻¹ had been previously applied. Dry matter yields were greater from the one-cut than the two-cut regime only in years when no N-fertilizer was applied. Knife placement of N-fertilizer increased total DM yield only at 100 kg N ha⁻¹. Tiller densities were generally higher under the one-cut than the two-cut regime, particularly when N-fertilizer was broadcast. The application of N-fertilizer increased herbage production, especially when responses in the year subsequent to application are considered.  相似文献   

The productivity and response to inorganic fertilizers of species-rich wetland hay meadows on the Somerset Moors: the effect of nitrogen, phosphorus and potassium on herbage production     

F. W. KIRKHAM  R. J. WILKINS 《Grass and Forage Science》1994,49(2):163-175

The effects of fertilizer nitrogen (N), phosphorus (P) and potassium (K) on herbage production were investigated in herb-rich hay meadows in Somerset, UK. Swards were cut after 1 July each year, followed by one or two aftermath cuts. Dry-matter (DM) yield at cutting, metabolizable energy (ME) production and recovery of N, P and K were measured over 4 years.
Total annual DM production increased from 4·7t ha⁻¹ without fertilizers to 10·5t ha⁻¹ with 200 kg N, 75 kg P and 200 kg K ha⁻¹ per year, and ME output from 38·8 GJ ha⁻¹ to 92·5 GJ ha⁻¹. Applying moderate replacement rates of P and K without N increased annual DM and N yields by 43% and 36% respectively, but N response was modest unless high rates of P and K were used. Annual ME output and recovery of N, P and K were all significantly increased by taking an additional, earlier cut for silage, even though DM yield was unaffected.
The results suggest that potential output of these meadows is similar to that of a wide range of less diverse permanent pastures. Data from this and a concurrent experiment will help to estimate the financial implications of fertilizer and cutting date restrictions within Sites of Special Scientific Interest and the wider Environmentally Sensitive Areas.  相似文献   

Slot-seeding investigations     

R. J. Haggar  D. W. Koch 《Grass and Forage Science》1983,38(1):45-53

Red clover cv. Hungaropoly was slot-seeded into a perennial ryegrass-dominant sward in April 1979. Glyphosate and paraquat were applied separately as bandsprays each at two doses and at two band widths. Control plots were either slot-seeded without a herbicide bandspray or received ±150 kg N ha⁻¹ a⁻¹. Red clover establishment was assessed and amounts of dry matter (DM) and total N accumulated were measured at two harvests in 1979 and three harvests in 1980. Bandspraying increased seedling vigour and development and resulted in the eventual replacement of 1 t grass DM ha⁻¹ by an equivalent amount of red clover. Of the treatment variables investigated, bandspray width had the greatest influence on red clover establishment and productivity. The slot-seeded area, meaned for all treatments, produced a total of 6.40 and 13.16 t DM ha⁻¹ in 1979 and 1980. This was estimated to be equivalent to the all-grass sward receiving 112 kg N ha⁻¹ a⁻¹ during the second year of the experiment or 238 kg N ha⁻¹ over the 2 years when measured in terms of N yield. Slot-seeding overcomes several of the problems associated with conventional establishment of red clover.  相似文献   

The liveweight gain of Limousin × Friesian heifers grazing perennial ryegrass/white clover swards of different clover content and the effects of their grazing on sward botanical composition     

N. H. Yarrow  & P. D. Penning 《Grass and Forage Science》2001,56(3):238-248

An experiment was carried out in 1992 and 1993 to examine the effect of white clover content of perennial ryegrass/white clover swards on the performance of Limousin × Friesian heifers. Swards with low (L), medium (M) and high (H) white clover contents were established and managed by continuous variable stocking. A compressed sward height of 5·5 cm was maintained using a buffer fence to vary plot areas, with herbage surplus to grazing requirements cut, removed and yields measured. The mean white clover proportions for treatments L, M and H were 0·02, 0·19 and 0·18 in 1992 and 0·13, 0·16 and 0·31 in 1993 respectively. White clover contents of the swards reached a maximum in August and September, and differences between treatments diminished. There was no significant difference between treatments in the content of white clover in the swards in autumn 1993.
Liveweight gains of heifers increased asymptotically with increasing white clover content of the sward. Below a white clover herbage mass of 300 kg DM ha^–1, there was little effect on liveweight gain, which was 0·70 kg day^–1 over the grazing season. Between 400 and 450 kg DM ha^–1 white clover, liveweight gains were 0·85–0·90 kg day^–1. While clover content of the sward did not significantly affect utilized metabolizable energy output; the mean output over the grazing season in the two years from liveweight gain and herbage yield was 78 GJ ha^–1. It is suggested that, using this grazing system, white clover reached an equilibrium with a mean herbage mass of about 400 kg DM ha^–1 over the grazing season.  相似文献   

Comparison of white clover varieties under cutting and grazing   总被引：2，自引：0，他引：2  

G. SWIFT†  M. W. MORRISON†  A. T. CLELAND†  C. A. B. SMITH-TAYLOR†  J. M. DICKSON‡ 《Grass and Forage Science》1992,47(1):8-13

Seven varieties of white clover ( Trifolium repens L.), of varying leaf size from large to small, were sown with perennial ryegrass ( Lolium perenne L.) in 1985, at an upland site, and compared over three harvest years under a cutting management (5-6 cuts), and under continuous grazing by sheep. Fertilizer N input totalled 80 kg ha⁻¹ in both the cutting and the grazing trial. The same varieties were included in two official National List (NL) trials sown the same year at a nearby site; these comprised a yield trial with 6-7 cuts and a persistency trial mown very frequently (17 cuts) to simulate intensive grazing.
At the upland site the large-leaved varieties, Milkanova and Blanca, were the highest yielding under cutting (mean 3·3 t DM ha⁻¹), and the small-leaved S184 and Kent the lowest yielding (mean 2·3 t DM ha⁻¹). The rankings were reversed under grazing (corresponding yields 1·1 and 2·1 t DM ha⁻¹). The medium-leaved varieties Donna, Menna and Grasslands Huia behaved similarly to the large-leaved varieties. Ranking order in the cutting trial was similar to that in the NL trial.
Ground covers after three harvest years differed significantly only under grazing, when the small-leaved varieties had a 2-3 times greater cover than the larger-leaved varieties. A poor separation of the varieties in the NL persistency trial suggests that defoliation was not sufficiently severe to simulate intensive grazing.
These comparisons indicate that the performance of clover varieties under the cutting regimes used should not be extrapolated to continuous sheep grazing.  相似文献   

Effects of different rates and timing of application of nitrogen as slurry and mineral fertilizer on yield of herbage and nitrate-leaching potential of a maize/Italian ryegrass cropping system in north-west Portugal     

H. Trindade  J. Coutinho†  S. Jarvis‡  N. Moreira 《Grass and Forage Science》2009,64(1):2-11

Efficient use of cattle-slurry to avoid nitrogen (N) leaching and other losses is important in designing intensive dairy systems to minimize pollution of air and water. The response in dry-matter (DM) yield of herbage and nitrate-leaching potential to different rates and timing of application of N as cattle slurry and/or mineral fertilizer in a double-cropping system producing maize ( Zea mays L.) silage and Italian ryegrass ( Lolium multiflorum Lam.) was investigated in north-west Portugal. Nine treatments with different rates and combinations of cattle slurry, and with or without mineral-N fertilizer, applied at sowing and as a top-dressing to both crops, were tested and measurements were made of DM yield of herbage, N concentration of herbage, uptake of N by herbage and amounts of residual soil nitrate-N to a depth of 1 m, in a 3-year experiment. Regression analysis showed that the application of 150 and 100 kg of available N ha⁻¹ to maize and Italian ryegrass, respectively, resulted in 0·95 of maximum DM yields of herbage and 0·90 of maximum N uptake by herbage. Residual amounts of nitrate-N in soil after maize ranged from 48 to 278 kg N ha⁻¹ with an exponential increase in response to the amount of N applied; there were higher values of nitrate-leaching potential when mineral-N fertilizer was applied. The results suggest that it is possible in highly productive maize/Italian ryegrass systems to obtain high DM yields of herbage for maize silage and Italian ryegrass herbage with minimal leaching losses by using slurry exclusively at annual rates of up to 250 kg available N ha⁻¹ (equivalent to 480 kg total N ha⁻¹) in three applications.  相似文献   

Effect of fertilizer nitrogen rate and timing on herbage production and nitrogen use efficiency for first-cut silage     

F. N. J. LONG  S. J. KENNEDY  H. I. GRACEY 《Grass and Forage Science》1991,46(3):231-237

Eight field-plot experiments were carried out on established grassland swards between 1984 and 1988 to examine the effects of date and rate of application of calcium ammonium nitrate (CAN) on herbage dry matter (DM) yield and apparent efficiency of nitrogen (N) use at first-cut silage.
CAN application significantly increased ( P <0 ·001) the mean yields of herbage and N uptakes by herbage in all experiments. Herbage yields were similar ( P > 0·05) with N rates of 100 kg ha⁻¹, 125 kg ha⁻¹ or 150 kg ha⁻¹ in five experiments but in the other three there were increases above 100 kg ha⁻¹. Date of N application had a significant effect on DM yield in three experiments; this effect was inconsistent for both single and split dressings. Lower production was associated with reduced uptake of N, a trend that primarily reflected lower DM yields and not wide herbage N content variation.
It is concluded that selection of the date on which to apply fertilizer N in early spring to obtain optimum herbage yields at first-cut silage often required little precision. The use of fertilizer N rates >100 kg ha⁻¹ should be questioned where there are likely to be appreciable quantities of available N derived from non-fertilizer sources.  相似文献   

The future of sainfoin in British agriculture: an economic assessment     

C. J. DOYLE  D. J. THOMSON  J. E. SHEEHY 《Grass and Forage Science》1984,39(1):43-51

In view of the revived interest in sainfoin, an economic assessment of the prospects for an expansion of its area in Britain has been attempted. It is estimated that potentially it could be grown on 950 × 10³ ha of the agricultural area of England and Wales, though it is unlikely in the near future that it would exceed 20 × 10³ ha, even if economic conditions were favourable. Comparison of the energy and protein yields of sainfoin, red clover and lucerne under conservation management indicates that one of the attractions of sainfoin is its high protein content. However, an assessment of the costs of production and utilization of sainfoin indicate that, for it to be a more widely used legume, sustainable dry matter (DM) yields would need to be increased by 35% to about 11.5 × 10³ kg DM ha⁻¹. At the same time, although growing sainfoin as a mixture with grass appears to improve the economic attractiveness of the crop, silage production costs (kg DM)⁻¹ are still about 15% lower on pure grass swards. However, trials in the UK, Canada and Rumania have shown that, compared to current UK levels, sainfoin yields can be significantly increased.  相似文献   

Agronomic performance and nutritive value of common and alternative grass and legume species in the Peruvian highlands   总被引：2，自引：0，他引：2  

K. Bartl  J. Gamarra†  C. A. Gómez†  H.-R. Wettstein  M. Kreuzer  H. D. Hess‡ 《Grass and Forage Science》2009,64(2):109-121

The agronomic performance and nutritive value of twelve annual and perennial grasses and legumes were analysed in order to define alternatives to local forages for dry-season feeding of ruminants in the Peruvian Andes. There were twelve species and two fertilizer treatments (no fertilizer and a N;P;K fertilizer mainly applied at sowing) in an experiment with a randomized complete block design with three replicates at each of two sites. Plant height, soil cover by forage and weed species, frost damage, dry matter (DM) yield and nutritive value of herbage were evaluated in 2005 and 2006. Among the annual species, Hordeum vulgare L. cv. UNA 80 and × Triticosecale Wittm. had the highest DM yields when fertilized (8226 and 6934 kg ha⁻¹ respectively). Without fertilizer the alternative cultivars had similar DM yields to that of the local forages. Cultivars of Avena sativa L. had lower concentrations of neutral-detergent fibre (NDF) (557 g kg⁻¹ DM) and higher concentrations of predicted net energy for lactation (5·86 MJ kg⁻¹ DM) than the other annual grass species (625 g kg⁻¹ DM and 5·01 MJ kg⁻¹ DM respectively), while the legumes were superior in concentrations of crude protein (277 g kg⁻¹ DM) and NDF (362 g kg⁻¹ DM). Considering the low agronomic performance of the perennial forages, a mixture of fertilized annual grasses and legumes appears the most appropriate approach to meeting the demand for forage of high nutritive value in the Peruvian highlands.  相似文献   

Effect of rainfall and temperature on yield of Vicia sativa under rainfed Mediterranean conditions     

I. PAPASTYLIANOU 《Grass and Forage Science》1995,50(4):456-460

The productivity of Vicia sativa grown in rotation with barley under rainfed Mediterranean conditions was examined at two locations over several years (eighteen location × year situations). Rainfall during the growing season ranged from 200 to 500 mm. Vetch relied on indigenous rhizobia for nodulation and N fixation while for phosphorus it was fertilized with 20kgPha⁻¹. Harvesting took place at the beginning of pod formation. The dry matter (DM) yield reached 6·6t ha⁻¹ and the N offtake 215 kg ha⁻¹. The highest yields were obtained when rainfall exceeded the 350 mm level. The N concentration of the forage was not influenced by rainfall or by the productivity of the plants. Yield of DM was related to the number of days of ground frost in January but not in February and March. Monthly minimum and maximum temperature was not related to the DM yield. The combination of monthly rainfall and temperature explained over 95% of the variation in yield.  相似文献   

Response to late season nitrogen of upland swards in Wales     

R. J. SKINNER  J. W. ALLEN 《Grass and Forage Science》1991,46(3):269-276

During 1984 and 1985, trials at sixteen sites throughout Wales measured the yield response in upland swards from applying 40 and 80 kg N ha⁻¹ at three dates, 20 August, 4 September and 18 September. All sites were between 230 m and 345 m above sea level. Grass yields were measured by cutting plots during October and November.
Nitrogen increased the herbage dry-matter (DM) yield at all sites in both years. The yield response per kg N applied varied between sites. Mean yield response for the two years declined from 16·2 kg DM kg N⁻¹ with 40 kg N ha⁻¹ applied on 20 August to 8·9 kg DM kg N⁻¹ with 80 kg N ha⁻¹ applied on 18 September. In general there was a decline in response to N with increased rate and delay in time of application. The results indicate that responses above an optimum of 9 kg DM kg N⁻¹ can be obtained well into September. A general rule that 1 kg N can be economically applied per 4 summed day degrees air temperature >6 °C remaining in the autumn up to 30 November is suggested.
Delay in application and increasing N rate increased crude protein in the herbage but had only small effects on modified acid detergent (MAD) fibre and sugar. Generally, grass quality was good. Sward density assessed during the spring after nitrogen had been applied appeared to have been unaffected by the treatments.  相似文献   

Nitrate leaching from cut grassland as affected by the substitution of slurry with nitrogen mineral fertilizer on two soil types     

J. J. Schröder  F. B. T. Assinck†  D. Uenk  G. L. Velthof† 《Grass and Forage Science》2010,65(1):49-57

A field experiment was conducted to find out whether there is any difference in risk of N leaching to groundwater when cattle slurry and/or mineral fertilizer-N was applied to cut grassland. The experiment was carried out over two consecutive years on two sites (one with a relatively wet sandy soil and one with a relatively dry sandy soil). Treatments were mineral fertilizer-N at annual rates of 0–510 kg N ha⁻¹ year⁻¹ and combinations of sod-injected cattle slurry (85, 170, 250 and 335 kg N ha⁻¹ year⁻¹) and mineral fertilizer-N (289, 238, 190 and 139 kg N ha⁻¹ year⁻¹). Yield responses indicated that in the short run, 0·44–0·88 (average 0·60) of the slurry-N was as available as mineral fertilizer-N. The total N input from mineral fertilizer and slurry was a worse predictor of nitrate leaching (     0·11) than the N surplus (i.e. the difference between total N input and harvested N) (     0·60). The effective N surplus, based on the difference between the summed inputs of the plant-available N and harvested N, proved to be the best indicator of leaching (     0·86). Annual N application rates of up to 340 kg plant-available N ha⁻¹ complied with the target nitrate concentration in groundwater of 11·3 mg N L⁻¹ set by the European Union in both years on the wet sandy soil, whereas on the dry sandy soil none of the treatments did.  相似文献   

The utilization of N fertilizer, applied to perennial ryegrass/white clover pasture growing on a humus iron podzol in N.E. Scotland     

ANNE RANGELEY 《Grass and Forage Science》1988,43(4):363-369

Applications of N fertilizer (0.40, 80, 120 and 240 kg N ha⁻¹ year⁻¹ in dressings of 40 or 80 kg N ha⁻¹) were made to a perennial ryegrass/white clover ( Lolium perenne L. Trifolium repens L.) pasture growing on a humus iron podzol reclaimed from heather ( Calluna vulgaris L.) moor in 1982 and 1983. Where no N was applied, estimates of Ni fixation and mineralization were almost equal, being approximately 50 kg N ha⁻¹ year⁻¹ from each source. Apparent efficiencies of fertilizer use were generally low; for each dressing they ranged between –0·7 and 25·5 kg dry matter (DM)kgN⁻¹. Also, responses to N fertilizer were affected by previous dressings. The net N recovery in harvested herbage from application of 120 kg N ha⁻¹ year⁻¹ was 30 kg N ha⁻¹ year⁻¹.  相似文献   

Mineral concentrations in herbage and soil in a Pinus radiata silvopastoral system in north-west Spain after sewage sludge and lime application     

A. Rigueiro-Rodríguez  M. R. Mosquera-Losada  M. L. López-Díaz† 《Grass and Forage Science》2007,62(2):208-224

Silvopastoral systems in north-west Spain can reduce the risk of fires and promote multi-purpose forest land use. Fertilizer application is important for optimal pasture and tree production. The application rate of sewage sludge as a fertilizer is regulated and is based on its nutrient concentration, especially nitrogen. The aim of this study was to assess the effect of three consecutive years of application of different application rates of sewage sludge and inorganic fertilizer, with or without lime (2·5 t CaCO₃ ha⁻¹) on the ammonium, nitrate and exchangeable K, Ca and Mg contents in soil, and on the crude protein (CP), K, Ca and Mg concentrations in herbage in a silvopastoral system established under a 5-year-old Pinus radiata D. Don plantation with a density of 1667 trees ha⁻¹. The experiment was started in autumn 1997, when a pasture mixture was sown (25 kg ha⁻¹ Lolium perenne , 10 kg ha⁻¹ Dactylis glomerata and 4 kg ha⁻¹ Trifolium repens ). Changes in ammonium and nitrate content in the soil in response to liming and sewage sludge application reflected the initial pH of the soil. In general, liming increased the available Ca and Mg content in soil, and CP and Ca concentrations in herbage, but reduced exchangeable K content in the soil in the first year. Application of sewage sludge increased all of the measured nutrients in both soil and herbage.  相似文献