Search Results - (Author, Cooperation:T. Misselbrook)

2014-03-08

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Adaptation, Physiological ; Agriculture/economics/*methods/*trends ; Animal Diseases/epidemiology/prevention & control ; Animal Feed/statistics & numerical data ; Animal Husbandry/economics ; Animals ; Breeding ; Conservation of Natural Resources/methods/*trends ; Crops, Agricultural/supply & distribution ; Dietary Proteins/supply & distribution ; Dietary Supplements ; Ecological and Environmental Processes ; Female ; Food Industry/methods/trends ; Food Supply/statistics & numerical data ; Genetic Fitness ; Livestock/*genetics/*physiology ; Male ; Meat/supply & distribution/utilization ; Ruminants/genetics/physiology

1365-2494

Blackwell Publishing Journal Backfiles 1879-2005

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Cattle slurry was applied to grassland on two contrasting soils in autumn and spring between 1987 and 1990. Slurry was applied with or without the addition of acid, to lower the pH to 5·5, and, in autumn only, with or without a nitrification inhibitor. Ammonia volatilization, denitrification and apparent recovery of N by the cut herbage accounted for 61–86% of the ammonium nitrogen (NH4+-N) applied in slurry. Estimates from lysimeter experiments indicated that nitrate leaching from autumn application may have accounted for an additional 1–2% only. Acidifying slurry reduced volatilization losses to 1–12% of the NH4+-N applied, and the nitrification inhibitor halved denitrification losses from autumn applications. Reductions in nitrogen losses were reflected in significant increases in first-cut herbage yields which, for slurry applied in the autumn with acid and the nitrification inhibitor, were generally greater than those from 120 kg ha−1 N as ammonium nitrate applied in the spring. There were no significant differences between treatments at subsequent cuts in each season but, owing to the large increases at first cut, total yields were significantly higher for autumn-applied slurry with acid and nitrification inhibitor.

Electronic Resource

1365-2494

Blackwell Publishing Journal Backfiles 1879-2005

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

An experiment was carried out over 2 years on grass and grass/clover swards in SW England lo compare herbage yields and N recovery following surface application or shallow injection of cattle slurry at three different times of application. In the second year, losses of N via ammonia volatilization, denitrification and nitrate leaching were measured from applications to the grass sward. On the grass sward, there was no significant effect of time or method of application on dry-matter (DM) yield in the first year, although shallow injection reduced apparent N recovery (ANR) in the herbage by 45% when compared with surface application. In the second year, shallow injection reduced DM yields by 26% and ANR by 48%. On the grass/clover sward, there were no significant effects of time or method of application on DM yields or ANR in either year Inclusion of dicyandiamide (DCD) in the October slurry applications had no significant effect in the first year, but in the second year on the grass sward increased DM yield by 31% and 14% and ANR by 156% and 42% for shallow injection and surface applications respectively. Measurements in the second year on the grass sward showed a reduction in N loss by ammonia volatilization using shallow injection of 40% and 79% for March and June applications respectively. Losses due to denitrification were greatest following October application. Shallow injection increased denitrification losses following March application, but there were no significant differences following October or June applications. N losses due to leaching were small, with no significant difference between treatments. Reasons for the reductions in DM yield and ANR following shallow injection, despite the large reduction in N loss by ammonia volatilization, are discussed.

Electronic Resource

1365-2494

Blackwell Publishing Journal Backfiles 1879-2005

Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Experiments were conducted on a grassland site at Wrest Park, Silsoe, Bedfordshire between 1987 and 1989, to compare herbage yields from slurry applied by deep and shallow injection, low trajectory and conventional vacuum tanker methods. Slurry application rates for all spreaders were calibrated at 86 ± 5 t ha-1, an equivalent of c. 200 kg NH4+-N ha-1 applied in autumn or in spring.As expected, herbage yields following spring applications were higher than from autumn applications, with average mineral fertilizer equivalents of 122 and 89 kg N ha-1 respectively. Yields from the conventional and low trajectory spreaders showed no consistent differences. However, in both years, first cut yields from plots were significantly lower (P 〈 0·05) where slurry had been injected than where surface applications had been used by an average of 0·7 t DM ha-1. Subsequent cuts in 1988 demonstrated higher residual effects from injection so that annual total yields were similar from all slurry applications irrespective of spreader type.Analysis of N content revealed high N levels in herbage from deep injection plots. Mean concentrations of N in the herbage, expressed as a percentage of the dry matter, were 1·43 for surface treatments and 1·79 for deep injection in 1988, and 1·84 for surface treatments, 2·13 for shallow injection and 2·68 for deep injection in 1989.

Electronic Resource