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Showing posts from June, 2021

The most recent addition to my hockey stick collection - World Population Growth

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  Roser, Max, Hannah Ritchie, and Esteban Ortiz-Ospina. ‘World Population Growth’. Our World in Data , 9 May 2013. https://ourworldindata.org/world-population-growth .

Realistic increases in soil organic carbon % through land management: 0.5% over 20 years and worth every point

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This figure is taken from the PNAS study (Sanderman et al, 2017).  It is yet another hockey stick graph that shows the exponential impact of human activity over the last 300 years.  According to this study, since the period before Land USe Change (NoLU), the world's soils have lost 133 Petagrams (133 billion tons) of soil organic carbon (SOC) from the top 2 m and 37 Petagrams from the top 30 cm.  The total SOC stocks in the top 2m and 30cm before land-use change were 3144 and 899 Petagrams respectively so that losses are of the order of 4% of total carbon for both strata.  It seems reasonable that these losses place upper limits on the sequestration potential of soils. An average silt loam has a density of 1.33 g/cm3, 1.33 tons/m3.  One ha of soil has 3000 m3 in the top 30 cm, so 3990 tons of soil.  A soil with 5% SOC would have had 199.5 tons of SOC/ha.  After land use change it would have had 199.5 tons - (199.5 X 37/899) = 191.3 tons of SOC = 4.7%. At COP21 in 2015 a global proj

Increasing machinery weights, compaction, soil functioning and yield

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  Red line = dry conditions, Blue line = wet With all the problems facing food production, it can be difficult to see the wood for the trees.  It may help to focus on the really obvious ones.  This is one of them. Keller, Thomas, Maria Sandin, Tino Colombi, Rainer Horn, and Dani Or. ‘Historical Increase in Agricultural Machinery Weights Enhanced Soil Stress Levels and Adversely Affected Soil Functioning’. Soil and Tillage Research 194 (1 November 2019): 104293. https://doi.org/10.1016/j.still.2019.104293 .

Social Enterprise and "The Other Cannon"

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  Is it time to dust off Rennaisance economics, "The Other Cannon", which sees creative production of good things as an almost sacred economic activity rather than consumption of anything produced as a sound economic activity? In this model, capital is required to support the production of needed goods and services (good goods model). In the current model inherited from the Family Tree of neo-liberal economists, capital is required to mobilise a consumptive workforce who must surely spend more than they earn to return a profit to capital (the greed is good model). A current example of Rennaisance economics might be the Social Enterprise movement. In this example the relationship between capital and labour is inverted. People with the knowledge and skills to produce good things employ those with capital who lack the knowledge and skills. Those with capital work for those who produce because they recognise that they need the goods or services. Leadership comes from the producti