Pig Slurry

A field study was carried out over 4 years at one site in the Low Po Valley, Northern Italy, to examine the effect of various levels of pig slurry applications on alfalfa (Medicago sativa L.) productivity, solar radiation utilization, and nutrient removal. Treatments consisted of three liquid pig manure rates, estimated to provide in total 300, 450 and 600kgNha−1year−1 (PS300,

The physical properties of organo-mineral fertilizers (OMF) are poorly understood, but must be measured because they affect OMF transport, storage, handling, and soil behaviour. The aim of this study was to determine the relationships among physico chemical properties so that the number of measurements required by the industry during manufacturing is reduced. Organo-mineral fertilizers were granulated into 50 mixtures of composts, peat, and mineral fertilizers. Fifteen physical properties and 12 chemical properties were measured following standard and modified methods. Bulk density, easy and inexpensive to measure, significantly affected other physical properties (R2
0.74), such as tapped and granule densities and porosities, and crushing strength. In addition, concentrations of Fe, Mg, organic matter, and Na significantly affected many physical properties of OMF granules, whereas other chemical properties had a limited effect. These findings will directly affect OMF manufacturing by reducing time and costs needed for property measurements related to product development and quality control.

Maize (Zea mays L.) is a very important crop in many of the irrigated areas of the Ebro Valley (NE Spain). Intensive pig (Sus scrofa domesticus) production is also an important economic activity in these areas, and the use of pig slurry (PS) as a fertiliser for maize is a common practise. From 2002 to 2005, we conducted a field

Pig slurry is a by-product of livestock farms. It is used for the fertilisation of tilled soil. Good agricultural practice demands that slurry be stored in ponds. They are generally constructed from brickwork lined with cement or reinforced concrete. The durability of these mortars and concretes guarantees their impermeability. This paper presents the results of mechanical behaviour, porosity and X-ray

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.

Biogas may be utilised for Combined Heat and Power (CHP) production or for transport fuel production (CH4-enriched biogas). When used to produce transport fuel either electricity is imported to power the plant or some of the biogas is used in a small CHP unit to meet electricity demand on site. The potential revenue from CH4-enriched biogas when replacing petrol is