Críticas al paradigma de competencias en educación

For this project, we intended to identify farm clusters in the UK holding substantial numbers of livestock as a means to establish potential sites suitable for development of farm-based biogas networks. However, due to issues regarding the potential for data protection infringement it was only possible to source suitably disaggregated livestock data at the county level of resolution (NUTS3)10_{. It also proved difficult locating the relevant livestock}

data for Wales and Scotland. This review will therefore concentrate on providing an analysis of the agricultural landscape across English regions. Additionally, dairy cattle11 _{and pigs will}

provide the main focus on account that slurry from these livestock is easily and regularly collected through existing on-farm practices.

All livestock data was obtained from the Cattle Tracing System (CTS), kindly provided by the British Cattle Movement Survey, the June 2010 DEFRA agricultural census and from statistics available from DairyCo12_.

The spatial distribution of dairy cattle across England is heavily weighted towards the west of the country (Figure 6), most notably in the South West, the North West and an area to the North of the West Midlands.

10 _{Defra‟s agricultural census does hold livestock information for local authorities (NUTS4) although, crucially, the data held for} cattle is not separated into beef and dairy herds.

11 _{For this report considered as a female dairy cattle over two years old with offspring} 12_{http://www.dairyco.org.uk/}

Biogas networks 34

Figure 6 Dairy cattle livestock densities for NUTS3 regions (A) and 5 km2 _{areas (B)}13 _in

England

The South West alone is responsible for over a third of the England dairy herd. Dairy farming is widespread throughout the region with high numbers of dairy holdings stretching from Cornwall to Wiltshire and South Gloucestershire. Devon holds the greatest total number of dairy cattle of any English unitary authority (Table 22). However, the county is one of the largest in the UK at over 6,500 km2 _{and consequently Cornwall, Somerset and}

Dorset all have higher densities of dairy cattle.

A region comprising the North West Midlands (Shropshire and Staffordshire), West Derbyshire and Cheshire is responsible for a further quarter of the national dairy herd. Farming is particularly intensive in Cheshire where density of the livestock is nearly twice that of any other English county having almost 50 dairy cattle per km2 _{across the entire}

region. The North West (Cumbria and Lancashire) also contributes significantly to dairy farming in the UK and is responsible for around 15% of the dairy herd in England.

13 _{Defra, Agricultural Atlas, June 2010}

Biogas networks 35

Table 22 Numbers of dairy cattle and commercial dairy holdings for NUTS3 regions in

England with the greatest dairy populations, 201014

County Number of livestock Number of Commercial

holdings Devon 130,279 920 Cheshire 93,368 566 Somerset 85,812 552 Cornwall 74,224 518 Staffordshire 72,318 565 East Cumbria 70,959 450 Shropshire 60,455 401 Dorset 58,702 337 West Cumbria 37,445 261

When establishing the potential for the development of biogas networks consisting primarily of slurry-fed digesters it is also important to consider herd sizes of dairy cattle. Dairy holdings with small numbers of cattle will be unable to provide sufficient slurry. It is far more likely that holdings comprising larger herds (>300 livestock) will show interest in the development of biogas networks. Smaller farms might be able to contribute to biogas networks comprising of a single, centralised, digester for which a number of surrounding farms provide feedstock, however this adds regulatory complexity.

For England counties with greatest numbers of dairy cattle, holdings with herd sizes above 300 livestock constitute 6 – 10% of all holdings. Average herd sizes are greatest in Dorset with 174 dairy cattle per holding while are lowest in Staffordshire (Table 23). As might be expected, Devon and Cheshire have the greatest number of holdings with more than 300 dairy cattle with 72 and 89 holdings respectively.

Table 23 Numbers of dairy cattle holdings for given herd sizes in English counties with the

greatest dairy populations, 201115

County <100

Livestock 101 to 300 Livestock 301 to 500 Livestock >500 Livestock Total Average Herd size

Cumbria 333 473 48 9 863 151 Cheshire 293 338 52 20 703 165 Shropshire 193 263 38 6 500 151 Staffordshire 320 284 43 4 651 128 Somerset 258 337 44 11 650 155 Dorset 154 235 26 12 427 174 Devon 478 528 65 24 1095 142 Cornwall 290 274 36 14 614 143

In contrast to dairy farming, holdings for pig livestock are more commonly situated in the East of England (Figure 7). The Yorkshire & Humber region and East Anglia are the two dominant areas of pig farming in the UK.

14 _{Defra, Agricultural census, June 2010} 15 _{Cattle Tracing System}

Biogas networks 36 Pig livestock holdings are widespread throughout Yorkshire; substantial numbers of livestock are present in North Lincolnshire and North Yorkshire (leading into South Teesside). North Yorkshire has more than 600,000 pigs in commercial holdings, more than any other English county (Table 24). However, the greatest density of pig livestock in this region, and indeed in all of England, can be found in the East Riding of Yorkshire. Cumulatively, this region is responsible for around one third of the national pig herd in England.

Norfolk and Suffolk also have a substantial number of pig livestock holdings and together the two counties hold nearly 1 million pigs, amounting to almost one third of the English pig herd. Livestock densities are fairly consistent throughout the region although they are slightly greater in Suffolk than in Norfolk.

Figure 7 Pig livestock densities for NUTS3 regions (A) and 5 km2 _{areas (B)}16 _{in England}

Table 24 Numbers of pig livestock for NUTS3 regions in England with greatest pig

populations, 201017

County Number of livestock

North Yorkshire 596,786

Norfolk 534,754

East Riding of Yorkshire 434,146

Suffolk 402,329

North Lincolnshire 70,420

16 _{Defra, Agricultural Atlas, June 2010} 17 _{Defra , Agricultural census, June 2010}

Biogas networks 37