Over 50 years ago seminars on "Population & food supplies" at Cambridge and Stanford Universities in 1967 and 1968 drew attention to the question of whether the carrying capacity of natural systems was able to support the increasing human population and the state-of-the-art of human activities. In 1972, an MIT report entitled, "The Limits of Growth" was launched by the Club of Rome gaining more publicity. A phase of increasing crop yields and genetic innovation with increased areas of cultivation and modern inputs meant the carrying capacity was able to rise from 3.5 billion people to 7.0 billion in 50 years. However, a misreading of agroecological studies on the impact of rising temperatures has caused an over-optimistic view of the impacts on food production. In reality, climate change is causing crop yields to fall due to excessive seasonal temperatures and loss of water. We face a future in which the balance between the consumption needs of a rising world population and a falling carrying capacity and declining production. This brings human population policies centre stage.
Population and food supplies
Population and food supplies was the title of two seminars. The first was held by the School of Agriculture at Cambridge University in 1967 and the second was held by the School of Engineering at Stanford University. Both came to similar conclusions concerning the risks to the human population's survival linked to the state of the natural environment and ecosystems because of the limits on natural carrying capacities. In terms of crops, carrying capacity is measured in terms of sustainable biomass or yield measured in kg/ha. What constitutes food depends upon the nature of the crop and what part of the crop is eaten by humans such as:
In reviewing how remote sensing data could be used this work reviewed how the variations associated with bioclimatic were impacted by altitude. A decision analysis model showing the relationship between fertility, water availability and temperatures was developed (see right).
The emphasis on carrying capacity is contained in a formula linking food production capacity and the consumption requirements of a growing human population.
Evolution of knowledge and action
In 1986, the development of a generic approach to data set specifications for decision analysis models was initiated which is directly applicable to the analysis of agricultural production under changing conditions. This approach, now known as Locational-State Theory provides a way to create a typology of farm sites according to the principle locational-state natural resource variables that determine yields. This approach was based on the earlier work completed at Stanford and from experience in Brazil related to coffee production. For example, in Brazil, the changes in temperature between 1975 and 2015 resulted in coffee production centres moving two times as a result of changes in the locational-state factors. In 1975, the frequency of frost in the State of Paraná caused market disruptions because of loss of production. Therefore coffee production moved to North East São Paulo State further North and nearer the Equator. However, by the 1990s the coffee crop in this region was subject to vary variable production and in some years there was no crop. Work by Brazilian agrometeorologists and agronomists found that if the temperature in the flowering season rose above 33oC the flowers were damaged or killed. As a result there as no fruit (berry) formation and a reduced or no production resulted. Coffee production was therefore moved during the early 2000s to higher altitude locations in the State of Minas Gerais, where the ambient temperatures are lower and flowering seasons do not experience temperatures in excess of 33oC and which became the largest coffee producing state in the country. Two conclusions arose from this experience based on locational-state analysis and the production biomass model. The levels of disruption took place with small rises in the moving average of temperatures, in fact less than 0.5oC over the period. The reason for the disruptive nature of the coffee production experience is that agroecological zoning, which is based on moving average conditions of temperature, rainfall, fixed terrain characteristics such as altitude and soil texture, ignored the seasonal variance in temperatures and rainfall. In most regions of the world there is a seasonal cycle of around 4-5 years which involves warm, cool, wet and dry years involving variations of around +/- 15% of the target measure. Therefore although a moving average temperature might indicate a flowering season temperature of 30oC, in a warmer part of the seasonal cycles the temperature is going to rise to 35oC, resulting in the death of most flowers.
There is therefore a problem linked to the genetic potential of crops in a rapidly changing agroecological environmental transition. Crops that have taken many years to adapt to specific conditions now face rapidly changing conditions. Worldwide, the proportion of the thousands of crops and crop varieties that are tolerant of high temperatures and drought is limited and it takes too long to breed new varieties with these properties. As a result we face a crisis associated with the fall in carrying capacity and ability to produce food. The question of the size of the population therefore becomes a major factor in adjusting to a declining carrying capacity.
Misinterpretation of agroecological studies
One of the misinterpretations of several studies on the impacts of various rates of temperature increase on crop production has been the static view that if temperatures rise all that needs to be done is to relocate to a production site at a higher and cooler altitude. First the land vacated will be losing its carrying capacity and the land occupied will experience the same degradation in yields as a result of increasing water and temperature stress, as long as temperatures continue to rise. In most countries there is less upland than lowland leading to a state of affairs where the utilizable land area is declining, along with crop yields. This affects large agricultural as well as small agricultural sectors. For example it is expected that Brazil with a major agricultural sector will lose around 10.6 million hectares of land allocated to agriculture by 2030 as a result of climate change. The current occupation of Amazon tropical rain forest in Brazil is likely to break important water cycles that involve an interchange of water rising from the forest providing rainfall for central southern regions such as Sao Paulo with a vibrant agricultural sector. The destruction of the Amazon could accelerate the rate of loss of agricultural land in Brazil through declining carrying capacity, in spite of the fact forest is being occupied to create agricultural production.
Major gaps in practice of major institutions
In 2015 the United Nations launched the Sustainable Development Goals (SDGs) under Agenda 2030. There are 17 SDGs. Agenda 2030 is not sector-based. For example, there is no specific SDG that handles agriculture even although it is a primary production sector employing the majority of people in low income countries. There is a need for the rapid development of agricultural production systems or combinations of practice and crop genotypes that can conserve water and become more resilient in this transition to higher temperatures. There is a need, in terms of the development of agricultural projects, to improve project design.
At the moment something like 40% of agricultural projects fail and this includes projects approved by the World Bank. Hector McNeill, director of the George Boole Foundation (GBF), explained that this figure comes from World Bank project portfolio reviews of thousands of projects in 1992 and then in 2010.
The 2010 review by the Independent Evaluation Group (IEG) of the World Bank found that most projects have not been subjected to economic rates of return analysis. Whereas in the mid 1960s training in agricultural project evaluation made use of World Bank case studies and design methods, it appears that at that time something like 85% of projects were subject to Cost-Benefit Analysis (CBA). By 2010 this had fallen to 20% of all approved projects, contrary to Bank internal regulations. The IEG ventured to suggest that the reason CBA is not appropriate for certain projects because of the difficulty in assigning prices to output and cost-effectiveness is more appropriate. McNeill confirmed that in their a ten year review and analysis of project cycle management design standards, the OQSI (Open Quality Standards Initiative - a division of the GBF) found close to no evidence that such a substitution had taken place. Overall we seem to face a state of affairs in which the standards of agricultural project design were totally inadequate and remain unsuitable for today's dynamic and increasingly complex challenges.
Even basic evaluation criteria are not being applied effectively. For example OECD DAC have a set of evaluation criteria but provide no detailed guidance on how to apply them to the varied processes being evaluated and which change according to the phase of a project's cycle. As a result different evaluators, each with a different background and type of experience, can end up with different assessments for the same project.
The specific case of the Brazilian coffee experience is, in reality, being repeated worldwide with respect to most crops linked to the tolerance of different crops to increasing water and temperature stress.
This work is being developed by the London-based George Boole Foundation Limited established to address the development of solutions to the performance issues identified in the World Bank reports. Most of the work used by the Foundation is based on the work of the Decision Analysis Group of SEEL-Systems Engineering Economics Lab set up in 1983. SEEL is now a division of GBF.
Agenda 2030 suffers from too many Goals and over 230 indicators making the practical process of designing projects problematic; it is too complicated for many design teams and especially small teams. Some governments who seem to be unaware of the productivity yield trend issues, require that projects include Goals that can have no contributing benefits to reversing yield declines.
Many SDGs are what were known as cross-cutting issues and project teams have always faced difficulties in including them in projects with specific goals. By making these mainstream this has made the conception and design of effective projects more difficult, especially when governments and donors include too many Goals as project acceptance criteria. The 2019 Sustainable Development Report noted that under our form of applied economic development, income disparity continues to increase, sustainability of production and consumptions continues to decline and temperatures continue to rise.
With the added dimension of declining potential yields, the factor of carrying capacity moved to the foreground of projects and with this the size of the human population and state-of-the-art technologies of human activities. Because crop yields are now on a downward trend because of declining carrying capacity, and therefore production potential, the human population needs to be brought back into focus. In general the human population numbers have tended to be treated as given in the sense of representing a growing "demand" which needed to be satisfied by the production supply side. The period 1968 through 1998 gave the impression that technology could resolve the carrying capacity, yields and supply issues in rain fed agriculture. However, with climate change imposing a trend of falling crop yields such an optimistic attitude needs to be replaced by realism. On the side of policy and strategies, it is evident that we cannot continue to ignore the need for more effective population policies. This is because we are in a trap with rising population pressure and a declining capability to accommodate consumption needs.
With respect to the gaps in performance identified in the 2019 Sustainable Development Report The George Boole Foundation has developed Options Benefit Analyses a series of analytical tools to help project teams prepare project designs that address real incomes (to reduce income disparity), carbon footprints (to ensure a negative trend) and financial return based on locational-state genotypic sequencing (LSGS) and the last one being carrying capacity.
24/07/2021: This is an important article but what are the implications for the United Kingdom? i.e. UK farming and national self-sufficiency in food production for our population?
Partial reply received from SEEL-Systems Engineering Economics Lab a division of the George Boole Foundation Ltd.:
The average UK annual rainfall, temperature and relief maps provide an initial basis for understanding the relative likelihoods of climate change impacts on UK farming and communities.
Currently the regions most likely to be impacted are those regions that already have occasional seasonal temperature and water stress (TWS). Thus, the highest temperatures and lowest rainfall regions are in the South, Central and East of the country up as far as the East Anglia, the Midlands and North Eastern borders with Scotland (see maps 1 and 2). These regions will undergo a progressive intensification of TWS which for rain fed agriculture will also be associated with a progressive decline in attainable yields for the genotypes currently grown. The locational-state biomass production models indicate that moving to higher ground can result in lower temperature regimes. These higher zones, in the context of climate change, can be referred to as temperature refuges (TR). In terms of the distribution of TRs in the United Kingdom, Scotland, Cumbria, the Pennines and North York Moors and Wales have the most TR resources. Northern Ireland and Eire have some limited TRs (see map 3). The region with least TR resources are the regions previously indicated as having higher temperature and lower rainfall regimes (South, Central and East of the country up as far as the midlands and North Eastern borders with Scotland).
Although politicians and some climate scientists speak of net-zero by 2030, 2040 or 2050 this will not be a slow ride up until these arbitrary points in time. Because of the seasonal temperature/rainfall cycles this process will not be smooth but will accelerate in a "fits and starts" mode with some years undergoing severe drought and crop yield failures as well as others with intensive rainfalls causing flooding in the lower reaches of terrains.
The analysis above refers to rain fed open field production. Enclosed or "protected" production will have an increasing significance in its ability to recirculate water which in open field scenarios is lost being evapotranspired into the atmosphere. Evapotranspiration increases with temperature. Water conservation techniques, such as minimum tillage and mulching, can slow down the impacts of less rainfall, but on balance over time, moving to higher ground is a more effective temporary solution.
The habit of importing food from many countries raises the carbon footprint of our food which exacerbates the rise in temperature risks. Many agricultural food imports come from countries more at risk than the UK. This has created a dependency on production over which we have no control. Given the precarious economic circumstances and state of agricultural project performances in low income countries, there should be a UK self-sufficiency strategic plan for food. It is already late in giving consideration to this but it is needed to rationalize planning for the agricultural sector.
Dietary habits are likely going to have to change in support of self-sufficiency and lower carbon footprint agricultural activities or international market access.
Climate committees seem to be more optimistic they often refer to "opportunities" in agriculture such as using more productive varieties and going to higher ground as the solution. Is that true?
It is a national average edible biomass production capacity issue
This is not the case overall but in specific locations there will be increases in yields on higher ground and where there is sufficient water. Nationally the trend will be a progressive intensification of temperature and water stress which will lower the overall national carrying capacity in terms of potential production of biomass.
The discussion here is about rain fed agriculture (open fields where water comes from rainfall). The maps in the previous response show clearly that over 50% of the UK is in low lying areas with no temperature refuges so these areas will face a declining carrying capacity in terms of biomass production because of water and temperature stress - the critical factor is water loss and lack of water retention techniques. As a result, over 50% of the country will enter the declining yield state soon. It will become noticeable following the first two dry seasons combined with high temperatures which will help reduce stored water and thereby accelerate carrying capacity decline.
The trends in global carbon release are the main issue
No matter what is being stated about "sustainable agriculture", unless global carbon release is reduced more rapidly not just to net zero but to negative trends the transitions described above will continue.
Breeding helps but unlikely to be a solution
Breeding drought and temperature resistant varieties takes more time than the rate of carrying capacity loss so this is why LSGS is applied to maximize the use of proven TWS tolerant crops; but they are limited. This is a temporary solution which at least provides a basis for more accurate cash flow projections and overall better average yield.
There is a need for a national strategy on population and food supplies
As previously stated there needs to be a national food self-sufficiency strategy which has to reply on more effective climate change actions with respect to carbon.
Emphasis should be on technical solutions
There appears to be too much assertion that financial services will be invested in green growth and carbon trading but since the standards of oversight of carbon trading are so weak - making it ineffective - and project design, so lax, much of this ends up as empty words or green wash.
The promise of COP 26?
The UK government is making much of COP 26. There have been 27 years of ineffective action under the multiple COPS with lots of "agreement" but no delivery of "committed" funds. COPs started in 1994 under the United Nations Framework Convention on Climate Change. This was organized 26 years after the Cambridge and Stanford seminars on "Population and food supplies" and the MIT's' "The Limits of Growth". We have drifted from year to year signing agreements while in reality there has been no action, many promises of funds and no funds being transferred.
There is a constitutional issue that threatens humanity
These international efforts are too dominated by politicians facing tight domestic electoral cycles which impose a condition of effective irresponsibility because, for them, domestic election processes are more important than acting in coordination with people concerned with "external issues".
Business interests very much see this crisis as an opportunity to make more returns through financial means and their lobbying of government and funding of political parties means that governments mould national objectives in terms of "saving the planet" while basing their effective "strategies" on business financial priorities. This, in reality represents a gap in the ability of constitutions to safeguard the existential interests of the national constituency.
We are going in the wrong direction
The UN Sustainable Development Report of 2019 makes clear that our form of economic growth, driven by economic policies and the activities of business corporations are failing to reduce income disparity, but are increasing it, they are failing to raise sustainability, but rather, are reducing it and their activities continue to raise national carbon footprints.
UK "net-zero" and all that
For the UK it is better to work out the balance of carbon footprints on all that is consumed (domestic production and imports) to account for imports from high carbon footprint countries and processes. On this basis net-zero for the UK is a very long way off.
We face the results of 50 years of financialization and de-industrialization
This is the direct result of a poor state of affairs of our balance of payments and not being self-sufficient in most things and not having any industry. Most of this is the result of national economic policies and financialization which came on line in 1981.
Some observations so far ....
26/07/2021: Mention is made of temperature refuges. Is there a formula relating temperature to altitude?
Yes. This is a relative difference relationship which is a based on a predictable gradient of temperature changes associated with altitude which is that for every gain of 100 metres in altitude there is about a 0.6oC fall in temperature. Or for every fall of 100 metres altitude there is a rise of about 0.6oC.
This relationship holds for all locations in the world. See the diagrams on the right.
In terms of average conditions a terrain coordinate at altitude 50 metres will on average have a temperature that is 2.7oC higher than a point at 500 metres altitude. The calculation is
Latitude influences the average temperatures depending on whether locations are closer of further away from the Equator.
In land masses, proximity to water bodies also impacts temperatures e.g. sea or very large lakes.
26/07/2021: That temperature difference over 500 metres seems to be small - what is the impact of such a small difference in temperatures?
This difference is essentially a "real time relative temperature difference" but average temperatures, used by the Climate Change buffs, varies during the year and 3oC can have a significant impact on comparative yields. However, as mentioned in the main article, the short to medium term issues are associated with seasonal variance which in the case of temperature can mean sometimes more than 5oC in excess of the warmer season averages leading to a rapid imbalance in the availability of water and temperature stress. Crop photosynthesis and growth, under our temperate conditions, effectively occurs between the temperatures of 3oC up to around 35oC max, so above this maximum there is no production. Combine that with less water and clearly yields are lower. Normally higher temperatures occur at harvest time which is good for such crops as grain and ripening fruits but, if in the "growing season", there was less water, yields fall.
Water is the exchange medium for plants to obtain access to nutrients extracted from the root layers. Water (H20) is also the major "input" to the plant production system (see box on right), along with CO2 which generates carbohydrate and oxygen.
In this context, as shown in that biomass production surface model soil conditions, and especially texture (size of particles), can have a direct impact of availability of water since water drains away from sandy soils, which consist of larger particles, and is bound too tightly by clay particles, which are considerably smaller, for roots to absorb (high water tension).
For further reading on this important topic it is worth looking at the biometrics page on the locational-state website here
27/07/2021: This is a matter of concern because the UK seems to lack an adequate natural resources base and, it would appear, is over-populated.
In terms of carrying capacity and self-sufficiency in food this is true in the case of rain fed agriculture.
There are some options linked to closed protected or covered systems which can support the production of several harvests each year, including through winter months, for the production of small greens. The production system plant layers can be stacked into shelves or suspended from gantries in containers. These systems can also be based on hydroponics and are best if they circulate and recover water. Use of specific wavelength LEDs reduce energy consumption and can run off solar conversion. Because of the stacked and multi-layered suspended characteristics it is possible to increase the yield per m2, doubling this with each layer. For this reason, such systems are claiming very high yields on a per hectare basis. However they most suitable products are greens and salad type products.
Given the inevitable decline in rain fed production yields the economics of closed systems is likely to become attractive as the basis for addressing these types of products. The planning aspects for this type of evolution have so far, as far as we are aware, not been advanced to any level of detail for the UK.
The experience with the lack of funding and collaboration over the vaccine COVAX and the tendency towards nationalism in the wake of the failure of globalization suggests this is a more serious risk and problem than many appear to be imagining. We are dealing here with food and for this reason a primary existential issue over which the UK has no natural advantages. There are no vaccinations against falling yields and scarcity of food. Any natural advantages that exist in other countries are being reduced by the forthcoming declines in yields in major production regions of exporting countries and the rising global population.
Up to now there has been no strategic planning with respect to the food access issue in the UK. This vital issue has taken a back seat to an over-blown media attention on "climate change" generalities and COP 26 which seems to be failing to focus on the true reasons for finding more urgent solutions to the temperature rise problem long before these arbitrary dates in the future.
We are entering a phase when a modern versions of the Corn Law tensions and the inaction over the Irish Potato famine, resulted in many deaths, come back to haunt our historic memory and conscience for a shameful legacy of inaction. We need to avoid getting into the position that, because we can afford to import food at inflating prices, others will perish. Or will this be a newfound post-BREXIT value to be promoted by the government?
Yes, rather than imploding the Department for International Development and cutting back on funding it would have made sense to augment funding in terms of finding more rapid solutions to our own problems, in this context, as well as assisting others. The government, however, continues to appear to be incapable of any strategic planning that will have practical results because of flawed economic logic and a somewhat impractical academic approach speaking of "World beating this and that". There appears to be an apparent issue in leadership of gaps in their education which seem to have occluded the ability to exercise a more objective and incisive recognition of what the issues are, prioritize them and then explain, in plain English, how they are to be addressed. Clearly, in reducing efforts concerning national health and future food supplies is by opting for inaction or ineffective actions, on the basis of current budget affordability" is an admission of incompetence. No one says any of this is easy, but the issue needs to be the centrepiece of the challenge to add urgency and action to what we do as a country to address this challenge.
The Department for the Environment, Food & Rural Affairs (DEFRA) seems to be more interested in grants and trade deals and lowering agricultural emissions. I have not found any mention of the falling yields question just mention of "opportunities". For a governemnt department this appears to be a significant oversight. The National Farmers Union also seems to be focused on CO2 emissions and net-zero while ignoring the fact that over the next 30 years yields are likely to drop significantly. The same appears to be the case for the Agricultural & Horticultural Development Board, although they are generally more practically orientated.
This raises important questions. We will send letters/emails to DEFRA, NFU asking and AHDB to solicit clarifications on their understanding of the situation and their opinion on the relevance of this question of yields. All official communications involved will be posted on this page.
In orde to initiate this process so we contact the right people, we are sending confidential emails to known advisers of these organizations in order to identify the most suitable individuals for soliciting a response from these organizations and which will be posted on this page.
In the main article it is stated that,
"..."Locational-State Theory provides a way to create a typology of farm sites according to the principle locational-state natural resource variables that determine yields."
Can someone explain why this is significant and how it works in practical terms?
LST provides an important perspective to improve experimental design because it can augment the explained variance in a datasets from agricultural field experiments by applying Fisher's analysis of variance (ANOVA). It is also essential in designing farm surveys that are use to establish production benchmarks for a particular enterprise (crop) across a territory used to estimate Gross Margins. This helps farmers pinpoint more exactly any performance gaps by separating out what was caused by locational-state variables in any season from the farms variable inputs (e.g. seed, fertilizer etc) and production systems adopted. More detailed content on this will be posted soon.
Typologies & LST
Farm typologies and plot typologies are ways to group farms and experimental plots into groups which share similar locational state variable conditions. This is an essential basis for simplifying statistical analysis through what is referred to as stratification. The European Union's Farm Accountancy Data Network (FADN) system, one of the largest regular sample surveys of farms in the world makes use of a simple typology for many years based on type of farming system and size of farm. The latest statement on this typology is in COMMISSION REGULATION (EC) No 1242/2008 of 8 December 2008, "establishing a Community typology for agricultural holding"
Examples of the farm groupings can be viewed here.
Unfortunately FADN is less concerned with farm management guidance and has drifted into policy impact analysis related to CAP. As a result, the evolution of FADN has not taken into account LST variables. There are attempts currently to bring FADN up to speed with respect to Sustainable Development Goals but this seems to have become bogged down within academic institutions with little of practical merit emerging.
Paradoxically, Locational-State Theory was a spin-off from a strategic project at the Information Technology & Telecommunications Task Force (ITTTF) of the European Commission in Brussels, which started in 1984. Locational-State Theory is a general dataset specification system that includes relevant natural resource variables as part of the dataset. They are included because they can be important determinants of the outcomes of any process that uses or is affected by natural resources.
The term "locational" refers to location of the objects of interest in space and time and the term "state" refers to the state or values of the variables of interest concerned over the range of the space-time coordinates.
This is applicable to a very large range of human activities and technologies. In the case of this discussion theme, the role played by LST variables in determining yields of crops or ecosystems is the point of interest.
In 1968 a review of agricultural field trial experimental results undertaken as part of a systems engineering course at Stanford Engineering School, showed that environmental factors were often not included in the either the data collected or in the subsequent analysis. Typical examples were trials e.g. of fertilizers on specific crops, set up to compare a range of application levels with the corresponding yield and to compare these with a plot where no fertilizer had been applied, referred to as the "control". From experience with farm surveys to collect benchmark data to calculate gross margins it was known that in different years, even applying the same levels of inputs, such as fertilizer, yields could vary significantly. This variance between years, because no data has been collected on, for example rainfall or temperatures, resulted in the analysis of variance of these experimental results, ending up a considerable amount of the "unexplained variance" attributable to water availability and temperatures. As a result the experimental logic was "isolated" from, as opposed to being "integrated" with, the dominant environmental factors.
Additional important data that was often not recorded were the altitudes of the experimental plots or farms and the soil textures.
University instruction in agricultural statistics and biometry for experimental and survey design did not include consideration of environmental factors but tended to focus on the isolated logic of the relationship between the cause and effect relationships being tested or assessed. There was therefore a fundamental flaw in this approach to applied statistics. Like mathematical logic, biometry is about measuring aspects of processes where the values of variables of interest to the researcher or surveyor (e.g. pesticides, fertilizer), determine the value of the effect (e.g. yield, insect damage). However, mathematical logic and biometry have greater potential contributions to the advance of knowledge. In establishing an experiment or carrying out surveys it is necessary to analyse and describe the ecosystem within which the object of the experiment (crop) or survey (farms) exist. What is being observed as a result of an experiment is the resulting phenotypic expressions of the complex interaction of a crop's genotype (genetic make up) with its environment.
The environment, however, is made up of natural resources including, rainfall, temperatures, terrain altitudes and soil texture and the inputs and technologies and techniques applied the researcher or farmer. The issue being investigated, in spite of a researcher's objectives, is highly complex. Unfortunately, much of the teaching in experimental and survey design encourages "simplification" in order to secure "results".
Ronald Fisher (1890-1962) although the designer of methods which have simplified experimental design and their analysis was completely aware of the limitations inherent in such an approach. In 1926 he wrote,
Typologies and LST
This brings us to an important LST concept of "incomplete" and "complete" datasets. Clearly the experimental data had missing information capable of explaining some part of the difference in response to treatments and was therefore an incomplete dataset. By including more relevant data the dataset would be more complete. Complete datasets have less unexplained variance than incomplete datasets.
Note (29/07/2021) There is a rather long article on this topic posted as number 6 in the series "Economic Policies for Agenda 2030" on "Agricultural Innovation" site some time ago, entitled "The significance of an extended farm typology for agricultural sustainability". We are preparing a summary of the main points to be posted soon.
Would it be possible to number comments to facilitate cross-referencing and navigation on this page?
Thank you for a useful suggestion. We have asked our web services team to look into this.
Some observations so far ....