Organic Farming

1.- Introduction

Increasing concerns about the UK’s food security are focussing attention on the productivity of sustainable methods of farming. This case study illustrates the productivity of a traditionally farmed 2.75 ha family farm in SE England, using data gathered over an 8 year period. The question addressed is as follows: How many people can traditional farming on this holding feed, on the basis of a balanced diet?

Traditional agriculture is defined as “the original farming method handed down from generation to generation, involving the intensive use of indigenous knowledge, natural resources and cultural beliefs of the farmer” [1]. Farmers and agriculturalists generally use the term to distinguish self-sufficient, subsistence-oriented, mixed farming from industrial, specialised farming. Traditional farming, according to these definitions, began in SE England in Neolithic times around 6,000 years ago [2] and, although continually evolving, was the only form of agriculture until the transition to industrial farming which can be said to have started in the late 18 ${}^{th}$ Century with the beginning of the Industrial Revolution. Traditional farming in this area can therefore be said to have supplied most of the food for the inhabitants on a millennial time-scale.

Traditional farming tends to conform to organic principles. Like organic farming, its self-sufficient, low input approach necessitates the use of organic fertilisers and non-reliance on imported materials, especially agrochemicals. Indeed, the organic movement, which started in response to the step-change in the industrialisation of farming at the end of the Second World War, is based on traditional farming principles.

The local traditional farming system was chosen for this holding because it was deemed to be highly sustainable, ecologically-beneficial and fitted with the family’s lifestyle aims. The broad principles were interpreted to be as follows:

Carrying capacity, as used in relation to food production from farming, has been defined as “the maximum number of people that a given land will maintain in perpetuity under a given system of usage without land degradation setting in” [3]. Implicit in this definition is that the farming system is sustainable and that the food provides a healthy, or balanced, diet.

Despite its importance to food security, few estimates of carrying capacity for UK farmland seem to have been made. Only two published sources, both based on theoretical calculations, have been found. In 1975, Mellanby [4] predicted that 11.0 million ha of Britain’s agricultural land were sufficient to feed its population of 53 million, based on the productivity of contemporaneous “conventional” farming and his estimates of a balanced diet. This equates to a carrying capacity of 4.82 people ha ${}^{-1}$ . In 2007, Fairlie [5] predicted the amount of farmland required to feed the then population of 60.6 million people under 6 different scenarios based on combinations of different diets and farming systems. Fairlie’s closest scenario to this case study is considered to be “Organic with Livestock” which was estimated to require 15.9 million ha of farmland, equating to a carrying capacity of 3.81 people ha ${}^{-1}$ .

However the actual carrying capacity of UK farming from historical data is suggested to be much lower than the above predictions. Historical estimates of carrying capacity at a national level can be made from published statistics for population, agricultural land area data and the national food self-sufficiency ratio using the following formula:

$C=(R\times P)/A$

Where:

C = carrying capacity (persons per hectare)

R = Food self-sufficiency ratio

P = Population

A = Agricultural land area (hectares)

The UK’s food self-sufficiency ratio is calculated by the UK Government using national statistics of indigenous food production and food imports. The ratio is sometimes called the “food production to supply ratio”. UK food self-sufficiency ratios, both contemporary and historical, are published by the Department for Environment, Food and Rural Affairs (DEFRA) [6]. Table 1 shows estimates of national carrying capacity for the UK’s farmland in persons per ha, calculated as explained above, for the years 1750, 1850, 1950 and 2000. Population figures are from Jeffries [7]. The calculation assumes that A, the area of agricultural land, has remained relatively constant at today’s figure of 18.7 million ha [8], which appears to be a reasonable approximation for this period from historical data [9]. The estimates show an increase in carrying capacity from 0.42 to 1.89. This increase is to be expected given the ongoing improvements in farming practices and livestock health and the increasing use of mechanisation and agrochemicals.

Other indications of UK farmland carrying capacity come from the period of the Second World War, when great effort was put into maximising indigenous food production due to the restriction of food imports by enemy action at sea. In addition the national diet was limited by enforced rationing. Despite all the effort and dietary restriction, by the end of the war the national food self-sufficiency ratio was estimated at only around 50%: “…you see the 46 millions in our island harassed about their food supply, of which they grow only half, even in wartime….” (Sir Winston Churchill, March 1946 “Iron Curtain” speech). This would indicate that only 23 million people could be fed by the wartime effort which, based on the same calculation method as above, approximates to a carrying capacity of 1.23 people per hectare.

The lack of information on the carrying capacity of UK farmland and the large disparity between theoretical predictions and historical measurements are, we consider, worthy of further investigation. This study aims to use empirical calculations to shed light on these issues at a farm scale.

2.- Material and Methods

3.- Results

4.- Discussion

The aim of this study was to measure how many people the holding could feed (its carrying capacity) from traditional farming on the basis of a balanced diet. The data, recorded over a period of 8 years, showed a carrying capacity of 0.64 people per hectare but the proportions of food types did not conform to a balanced diet. A balanced diet scenario was therefore constructed on the basis of the UK Government’s current recommendations which gives an increased carrying capacity of 1.09 people per ha.

The increase in carrying capacity for the balanced diet scenario reflects an increase in farming efficiency, mainly due to the following two factors:

It should be noted that the balanced diet scenario is estimated to require a near doubling of labour time compared with the study period. The increase in labour time would be mainly associated with dairy production (twice-daily milking and weekly cheese/butter-making for 6 months per year and hand-rearing of the calf) plus the increased production of wheat flour, fruit and vegetables.

It is not claimed that the data presented here are representative of the potential of a larger farm in a more commercial setting. It could be argued that factors such as a lack of profit-motive and economies of scale mean that productivity is less than it could be if this were the case. In making a judgement on this, the reader might consider the following three points:

The carrying capacity results from this study are significantly less, by a factor of more than three, than the theoretical predictions of Fairlie (2007; [5]) and Mellanby (1975; [4]). It is not the purpose of this study to investigate these discrepancies in detail but the following points should be noted:

First, the theoretical predictions of Mellanby (1975; [4]) were based on the productivity of contemporaneous “conventional” farming, which is widely accepted to have higher productivity than traditional farming.

Second, both theoretical predictions are based on a balanced diet but the components are somewhat different to that used by this study. The diet in the theoretical predictions has a higher proportion of carbohydrates (cereals and potatoes) and dairy and a correspondingly lower proportion of fruit and vegetables and meat. This might explain some of the greater productivity calculated by the theoretical predictions but it is not obvious how this factor could cause such large discrepancies.

Third, the theoretical predictions of Fairlie (2007; [5]) are constructed on a livestock-based organic farming system similar to the traditional farming system used in this study, therefore carrying capacity would be expected to be similar. This is problematic, however Fairlie (2007; [5]) emphasised that there were ”limitations to this kind of theoretical exercise” and that his article was ”intended as a rough guide and a useful framework for thinking about such matters”.

5.- Conclusions

This case study shows that traditional farming on a 2.75 ha holding in SE England has a carrying capacity of 0.64 people per hectare on a food energy basis alone without any dietary consideration. This is based on 8 years of food production data recorded between 2010 and 2017. Carrying capacity rises to 1.09 people per ha when the production is re-proportioned to conform to a balanced diet, illustrating the greater efficiency of balanced diet-driven production from traditional farming.

The balanced diet scenario carrying capacity estimate of 1.09 people per ha is broadly comparable with this study’s estimates of UK national values for the middle of the 20th Century. It is much less than the theoretical predictions made by Mellanby (1975; [4]) of 4.81 people per ha although these were based on “conventional” farming methods which are generally accepted to have higher productivity than traditional farming. More problematically, it is much less than the theoretical prediction made by Fairlie (2007; [5]) of 3.81 people per ha which was based on similar farming methods to traditional farming. The subject of carrying capacity appears to be under-researched and the above discrepancies require further investigation.