Lewis Peake

This short article sets out the role that changes in land use and management can play in storing additional soil carbon (C) and contributing to the stabilization of global temperatures; and outlines some key messages and recommendations to policy makers from a soil science perspective. We set out how the global C cycle has been disrupted and how farmers can be supported in adopting sustainable soil management (SSM) practices that improve land productivity and the provision of multiple public services such as climate change mitigation.

The need for effective governance of soil resources is critical. This article outlines five levels of national soil governance against which states may assess themselves and highlights those the authors consider to be in the top category. Responding to the question Which countries or political states can be viewed as ‘global standard bearers of soil governance?’ it describes exemplars of national and subnational best practice that, if widely emulated, could significantly improve the condition of land and soil globally.

Collates all the research in erosion-induced loss in soil productivity that the authors have been able to find. Some 195 items of research are categorised according to geographical area, soil type, crop, research method and parameters studied. Analyses of research activity indicate that Aridisols and Oxisols are under-represented and good quantitative information is lacking on the other major soil types. Experiments which monitor nutrient losses and soil properties have problems: it might be more realistic and useful to concentrate on the remaining soil rather than the removed soil.

The continual loss and impairment of soil ecosystem services (SES) across the globe calls for a fundamental reconsideration of soil governance mechanisms. This critical synthesis charts the history and evolution of national and international soil law and seeks to unravel certain challenges that have contributed to this failure in governance. It describes and categorizes law and policy responses to different soil threats, and identifies a worrying widespread absence of legislation for oversight and protection of agricultural soils from urbanization, as well as a lack of clear legal mechanisms to determine national priorities for soil protection. A reduction in the world's prime farmland threatens SES, including food security, carbon storage and biodiversity. Falling between the stalls of agricultural and environmental law, the fate of farmland is often left to planners who do not see themselves as responsible for soils. Consequently, legal instruments with the greatest power to affect soil, sometimes irreversibly, are often framed and worded with little or no reference to the soil. Nevertheless, emerging conceptual frameworks might offer positive outcomes. The authors advocate robust holistic policies of soil governance and land use planning that place SES and natural capital at the heart of decision making.

"Evidence suggests that biochar influences soil physical properties, especially soil hydrology, yet relatively little
data exists on this topic, especially in relation to soil type or characteristics. This paper presents a novel attempt
at analysing the influence of biochar (applied at 0.1, 0.5 and 2.5%) on the physical properties of soilwith respect to
quantified soil variables. Pot experiments were used to establish the effect of biochar on: bulk density, soil moisture
content at field capacity and available water capacity. The aggregate effect of biochar across all soilswas significant
(P b 0.01) for all of the properties. With increasing amount of biochar, changes to bulk density, field
capacity and available water were more pronounced. In the 2.5% treatments these changes ranged from −4.2%
to −19.2%, 1.3% to 42.2% and 0.3% to 48.4%, respectively. Regression revealed that soil silt content negatively
moderated the influence of biochar on field capacity and availablewater capacity. The results suggested that medium
(20 t ha−1) and high (100 t ha−1) biochar applications could improve water-holding capacity (by up to
22%) and ameliorate compaction (by up to 15%) and that soils low in silt are likely to be more hydrologically responsive
to biochar application."

Data sources from Nigeria and the United States on Alfisols (Luvisols and Podzoluvisols), with supplementary information from Indonesia and Australia show a strongly exponential relationship between cumulative erosion and yield reduction. A total erosion of 10 mm or 140 t/ha will cause a 75 % reduction in yield on tropical Alfisols whereas on equivalent temperate soils crop loss is less dramatic. Yield loss is the result of changes in intrinsic soil properties such as water-holding capacity, rooting depth, soil acidity and loss in organic matter and not simply removal of soil.

From 712 BC until c.670 Kush and Egypt were united in a single Nile Valley empire stretching from the Delta to Khartoum. Possibly only under Thutmose III was the territorial extent of the Egyptian empire comparable. Egypt, under Kushite rule (the so-called “Black Pharaohs” of the 25th Dynasty), was one of two great superpower rivals in the eastern Mediterranean – the other being Assyria. Over a 45-year period, these two empires jockeyed for power until Assyria finally prevailed. Phoenicia’s hegemony over Mediterranean trade was being challenged by the emergent Greeks, but neither was a military superpower. The huge empires of Persia and Rome were centuries away. Beyond the region, even as far as India, China or the Americas, no truly unified power held sway over vast international territories anywhere. It is therefore suggested that Kush-Egypt and Assyria were probably the two most powerful nations on Earth. Furthermore, for part of that period - by certain criteria at least - it could be argued that Kush-Egypt was the more powerful of the two.  The conclusion of this argument is that, for a few decades perhaps, a Nubian ruled over the greatest political entity on the planet, yet this is virtually invisible to history. This paper establishes its basic premise by reviewing the status of Kush-Egypt, primarily in relation to Assyria, but also to the world at large, then goes on to analyse how historians and archaeologists have treated – or in many cases ignored – this episode in Kushite-Egyptian history. It is concluded that racism and misguided bigotry, originating mainly in the 19th Century, have partly led to an otherwise inexplicable depreciation of the significance of the 25th Dynasty’s role in history. Furthermore, this legacy has inevitably produced ongoing impacts that form a historiographical continuum up to the present day. Ignorance, indifference and inertia are embedded in the inherited approach and hence often perpetuated unknowingly. As a result, a profoundly significant period in Nubian history has been diminished and obscured almost to the point that it constitutes a lacuna in the historical record.

Current knowledge suggests that biochar can be applied to agricultural soils in order to boost crop yields and simultaneously sequester atmospheric carbon. Biochar could therefore have a role in ameliorating two of the major environmental problems facing humanity – climate change and food scarcity. Further benefits ascribed to biochar include reduced water demand (for irrigation), less downstream pollution and reduced emissions of greenhouse gases (eg NO2) from the soil. Evidence suggests that some of these effects are influenced by soil type. This ongoing PhD project is investigating the effect biochar has on a wide range of soil properties that influence productivity, in relation to soil type. Four distinct textural classes of soil widely found in eastern England (and surveyed in detail) are being compared, using four biochar treatment doses: 0, 0.1%, 0.5% and 2.5% w/w (equivalent to 0, 4, 20 and 100 t ha-1). Three types of experiment are being conducted: (1) Laboratory tests of soil hydrology, eg using Tempe cells; (2) Long-term outdoor pot trials with winter wheat; (3) Long-term farm field trials. Early results for pot trials to test available water capacity (AWC) show clear positive trends. It is expected that a great deal more data will have been obtained before presentation of the paper in September. The project will provide biochar data, which is lacking for this region, and extend our knowledge about the significance of soil type, which is also very scarce and fragmentary. By modelling and mapping the relative suitability of specific soils for amendment, according to various criteria, it is hoped that such information can pave the way for fine-tuning the strategic deployment of biochar. This methodology could be expanded and applied to other soils and other regions.

Research suggests that biochar can be applied to agricultural soils in order to boost crop yields and simultaneously sequester atmospheric carbon. Further benefits ascribed to biochar include reduced water demand (for irrigation), less downstream pollution and reduced emissions of greenhouse gases (eg NO2) from the soil. Evidence suggests that some of these effects are influenced by soil type. The University of East Anglia (UEA) in Norwich, with the first combined heat and power (CHP) plant powered by woodchip biogas in the UK, has the capacity to produce approximately 300 tonnes of biochar annually. The feedstock and production temperature are carefully controlled for consistency. UEA biochar is currently being investigated, on a large scale, in the first ever farm trial of biochar in the East Anglian region of England. This ongoing project is investigating the effect biochar has on a wide range of chemical, physical and hydrological soil properties that influence productivity. Four distinct textural classes of soil widely found in eastern England are being compared, using biochar treatment doses up to 100 t ha-1. The core trial site includes three soil types in one field under an 8-year arable rotation. Laboratory experiments and a long-term outdoor pot trial with winter wheat are also being conducted to support the field trial. Early results for available water capacity (AWC) show clear positive trends. Investigating responses to biochar according to soil type is a key feature of the project, the ultimate aim being to make predictive recommendations. The project will provide new data for this region and extend our wider knowledge about the influence of soil type in this context. It is hoped that such information can pave the way for fine-tuning the strategic deployment of biochar. This methodology could be expanded and applied to other soils and other regions. Presentation: http://www.meditbiochar.org/uploads/1/1/0/8/1108765/s1_05_peake.pdf

This is the first Science Note of the British Society of Soil Science (BSSS), on the topic of Soil Carbon. Our comprehensive note sets out the academic research concerning soil carbon which is used to define clear recommendations to governments. The note, which explores the importance of carbon in soils, how it behaves, and how it might be increased to help address the climate crisis, is available as a technical, fully referenced version or a shorter version, aimed at lay people.