Long Term Slurry on Grassland Experiment, Soil Organic Matter Network, Northern Ireland - DANI.Slurry

This experiment was initiated in 1970 at a site that was originally
temperate deciduous woodland. It then was an estate farm until the
agricultural institute founded in 1926. The area was cut grassland,
predominantly Lolium perenne L. sward immediately before the
experiment was established.

The experiment consists of a single land-use, cut grassland (3 cuts
per year). Treatments are as follows: 1) Fertilizer control (200 kgN,
32 kgP, 160 kgK /ha/y), 2) Unfertilized control (as 1 1970 to 1972 -
no amendments thereafter), 3) Pig slurry at 50 m3/ha/y, 4) Pig slurry
at 100 m3/ha/y, 5) Pig slurry at 200 m3/ha/y, 6) Cow slurry at 50
m3/ha/y, 7) Cow slurry at 100 m3/ha/y, 8) Cow slurry at 200 m3/ha/y.

The average climatic conditions at the experimental site are:

Minimum annual temperature: 5.5 deg C
Maximum annual temperature: 12 deg C
Mean annual rainfall: 872.5 mm

The soil is characteized as a clay loam slightly gleyed overlying
triassic sandstone and silurian shale. Classified according to soil
classification for England and Wales, Technical monograph 14 (1980).

Ap horizon 0-30cm - clay loam 7.5 YR 4/2. Bg horizon 31-50cm - clay loam
7.5 YR 68, mottles = 5 YR 5/8. Cg horizon
51cm and deeper - clay laom, 7.5 YR 4/6, Mottles = 5 YR 6/3.

The measurements made, methodology, and frequency are listed below:

a) Vegetation measurements made and frequency

Yield: 3 times per year
Total dry matter offtake: 3 times per year
Nitrogen content of offtake: 3 times per year
3 times per year for P, K, Ca, Mg (concentrations and offtakes),
Mn from 1982, Cu and Zn from 1987 and S from 1990.

b) Soil sampling

Time zero soil measurements were taken. A crude assessment of
site variability was made by dividing the area into 4 quadrants and
taking a composite soil sample from each quadrant on 6 November
1969. Sampling depth was 15cm. Each sample was analysed for pH,
extractable P and K. The data were not analyzed statisically. Each
February numerous cores are removed from each plot (core diameter =
1.5cm) with a half corer auger to a depth of 15cm. The cores are cut
into 3 5cm sections which are bulked to give a composite sample from
0-5, 5-10 and 10-50cm depth. About 500g of fresh soil is collected
from each depth in each plot. The cores are taken randomly from the
plot area. Soil is separated into layers Details of measuring depths
and soil layers: One composite sample per plot at depths 0-5, 5-10 and
10-15cm.

c) Soil measurements made and frequency

Total carbon: Annually 1971-1977 and 1980
Method of measuring total carbon: Tinsley method (MAFF) 1986 (see
J. Appl. Ecol. (1989) 26: 597 - in reference list).
Biomass carbon: Twice in 1978 and 1986
Method of measuring biomass carbon: 1978 (6 treatments) and 1986
(all treatments) by chloroform fumigation-incubation (see
J. Appl. Ecol. (1989) 26, 597 - in reference list).
Carbon dioxide evolution: Once in 1970
Method of measuring carbon dioxide evolution: Conducted once in
February 1970 using McFayden tubes inserted into two of the three
blocks of the experiment.
Total nitrogen: Annually 1971-1977 and 1980
Method of measuring total nitrogen: Kjeldahl digestion.
1986-Kjeldahl digestion following reduction of nitrate (Kalembasa &
Jenkinson, 1985).
Biomass nitrogen: 1978 and 1986
Method of measuring biomass nitrogen: Chloroform
fumigation-incubation. See J.Appl.Ecol. (1989) 26: 597 - in reference
list).
Other nutrients: pH in water (MAFF:ADAS method),
bicarbonate-extractable P, exchangeable K+ and Mg++. Full details in
J. Agric. Sci., Camb. (see reference list).

d) Details of the meteorological station

Nearest meteorological station to the site: Agricultural research
institute of Northern Ireland, Hillsborough. which is .04 km from the
site at coordinates 6deg.25min.20sec. West,
54deg.26min.50sec. North. The meteorological station is manual.

e) Meteorological data available and frequency

Rainfall: Daily
Air temperature: Daily
Soil temperature: Daily
Wind speed: Daily
Net Radiation: Daily
Sun hours: Daily
Relative humidity: Daily
Potential evapotranspiration: Daily

This information was compiled for the GCTE-SOMNET Database, Pete
Smith, Pete Falloon, David Powlson, and Jo Smith. Soil Science
Department, IACR-Rothamsted, UK.