Soil Science Research Articles

Effect of Different Tillage and Organic Inputs on Soil Properties and Yield of Cotton on Vertisols

The present investigation was carried out at Research Farm, Department of Soil Science, Dr. PDKV, Akola during Kharif 2023-24 to study the effect of different tillage practices and organic inputs on soil properties and yield of cotton on Vertisols. Intensive tillage accelerates the loss of soil organic carbon (SOC) and reduces soil quality and yields, particularly in rainfed areas. This is further worsened by imbalanced fertilization and insufficient recycling of organic residues. Conservation tillage, when combined with organic inputs like FYM, vermicompost and phospho-compost, can help to restore soil structure, increase SOC and promote sustainable agricultural practices. The study aimed to assess the effect of different tillage practices and organic inputs on soil properties and on yield of cotton. The factorial randomized block design with two factors and four tillage treatments as factor A and four sources of manure as factor B were adopted. The treatments were composed of factor A consisting of four tillage operations [conventional tillage (T1), reduced tillage (T2), minimum tillage (T3) and zero tillage (T4)] and factor B consisting of organic manures such as farmyard manure (10 t ha-1) (M1), vermicompost (5 t ha-1) (M2), phospho-compost (5 t ha-1) (M3) and no manure (M4) replicated thrice. The results clearly indicated that conventional tillage resulted in the significantly highest seed cotton yield (14.10 ha-1), stalk yield (27.78 ha-1), total uptake of N (46.46 ha-1), P (7.86 ha-1) and K (33.05 ha-1) relative to other tillage practices examined. Among the organic manure treatments the highest seed cotton yield (11.21 ha-1), stalk yield (21.95 ha-1), total N (37.27 ha-1), P (6.57 ha-1) and K (31.25 ha-1) uptake by cotton was observed with phospho-compost application. Based on the observed results, it was notable that the available soil N, P and K were significantly influenced by the distinct tillage practices and organic manures. Among the tillage practices, the highest content of available soil N (182.14 kg ha-1), P (17.14 kg ha-1) and K (312.95 kg ha-1) were exhibited by the reduced tillage. The use of vermicompost resulted in the highest available soil N (185.93 kg ha-1) and K (316.68 kg ha-1), while the highest available soil P (18.22 kg ha-1) was observed with phospho-compost. The results revealed that conventional tillage combined with phospho-compost improves cotton yield and nutrient uptake, while reduced tillage along with the application of vermicompost and phospho-compost improves soil fertility. Therefore, combined use of tillage and organic inputs could be beneficial for enhancing soil properties and higher productivity of cotton in Vertisols as well as the whole of Maharashtra.

Professional Practice of Soil Science

Professional Practice of Soil Science

Model ensemble techniques of machine learning algorithms for soil moisture constants in the semi‐arid climate conditions

AbstractIn recent years, the use of prediction models based on intelligent algorithms has become widespread in soil science. However, each algorithm has advantages and disadvantages, and variable results can occur on different datasets. The evaluation of ensemble techniques for solving these problems is the current approach. Water problems will arise due to global warming, and soil water will become more important. This study aims to evaluate the predictive accuracy of different machine learning algorithms (support vector machine regression (SVR), random forest (RF), artificial neural network (ANN), and multivariate linear regression (MLR)) and ensemble techniques (equal weight [EQ], Bates–Granger‐BG), Granger–Ramanathan (GR), Akaike information criterion (AIC), and Bayesian information criterion (BIC)) on the field capacity (FC), wilting point (WP) and available water content (AWC) of soils. As a result, higher prediction accuracy was obtained with the RF algorithm than with the value machine learning algorithm in the estimation of moisture constants. The coefficients of determination (R2) obtained for the prediction of FC, WP, and AWC via the RF algorithms were 0.624, 0.759 and 0.641, respectively. MLR had the highest error rate. Among the ensemble techniques, GR was the most successful. Lin's concordance correlation coefficient (LCCC) values obtained from the estimation of FC, WP, and AWC with the GR model were 0.801, 0.894, and 0.801, respectively. The root mean squared error (RMSE) and mean absolute error (MAE) values obtained in the estimation of the available water content with the MLR algorithm were 1.905 and 1.435, respectively, whereas these values were 1.173 and 0.767, respectively, when the GR model was used. As a result of the present study, better predictive results were obtained with ensemble techniques instead of evaluating the algorithms individually.

Examining the adaptability of soil pH to soil dynamics using different methodologies: A concise review

Soil pH is crucial to soil health, influencing nutrient availability, microbial activity, and plant growth. This review aims to assess the adaptability of soil pH under changing soil conditions by analyzing natural and human factors. Information was gathered from various sources, including peer-reviewed articles, field studies, and recent advances in soil science. The study explores how natural factors such as parent material, climate, and vegetation establish baseline soil pH, while human activities such as intensive farming and land-use changes further modify it, often leading to soil acidification or alkalinization. Traditional management methods like lime application, organic amendments, and crop rotation are reviewed for their effectiveness in stabilizing soil pH and their limitations under varying soil conditions. The review also explores modern technological innovations like precision agriculture, which uses soil sensors and variable rate technology for targeted pH management, and biological approaches, such as microbial inoculants, to enhance nutrient cycling and organic matter decomposition. Integrating these traditional and contemporary approaches is essential for sustainable soil pH management and long-term productivity. The findings highlight the need for a holistic approach that combines historical knowledge with emerging technologies to promote sustainable agricultural practices and environmental conservation.

Diversity and Prevalence of Indigenous Soil Bacillus spp. in the Major Cabbage Growing Agroecological Zones of Uganda

Different species of genus Bacillus have been reported from different environments of the world. They are reported to play a role of soil fertility improvement, plant growth promotion and disease and pest management. Most of these reports on Bacillus species are from studies conducted outside Uganda and therefore information on the prevalence and diversity of bacillus species in Ugandan soils is scanty. This study aimed at determining the prevalence and diversity of Bacillus spp. isolated from the cabbage rhizosphere in the four major cabbage-growing agroecological zones of Uganda. The experiment was conducted in a laboratory at the College of Veterinary Medicine, Animal Resources and Biosafety Makerere University for morphological and biochemical identification of the Bacillus bacteria. DNA extraction and PCR were conducted at the College of Natural Resources Makerere University while sequencing was done at Macrogen laboratories in Korea and Inqaba Biotec in South Africa. Morphological, biochemical and genomic analyses revealed five Bacillus spp. (22 Bacillus strains) grouped as B. cereus, B. mycoides, B. thuringiensis, B. megaterium and B. bingmayongensis. B. cereus and B. megaterium were the most dominant and widely spread Bacillus spp. A phylogenetic tree indicated three major clads, showing that B. thuringiensis was closely related to B. cereus while B.bingmayongesis was closely related to B.megaterium. The B. mycoides were closely related to some B. cereus strains and B. bingmayongensis. The phylogenetic tree further showed that some Bacillus strains of the same species were distantly related. It was therefore concluded that most abundant and prevalent Bacillus spp. in Ugandan soils were B. cereus and B. megaterium. The presence and abundance of these bacillus species in the Ugandan soil presents an opportunity for soil scientists to innovatively manipulate them for use as biofertilizers and biopesticides for crop production and management. Such innovations would reduce the reliance of farmers on synthetic fertilizers that are pollutants to the environment and unhealthy to the users and consumers

Organizer of biological science: to the 100th anniversary of P. A. Lehr’s birth

2023 marks the 100th anniversary of Pavel Andreyevich Lehr’s birth (09.27.1923–09.15.2005). He was an outstanding Soviet scientist, a leading expert on dipteran insects, a corresponding member of the USSR Academy of Sciences, director of the Institute of Biology and Soil Science of the Far Eastern Scientifi c Center/Far Eastern Branch of the USSR Academy of Sciences during 1981–1991. The article highlights the contribution of P. A. Lehr to the organization and development of biological research in the Far Eastern region between 1988 and 1991, when he was deputy chairman of the Presidium of the Far Eastern Branch of the USSR Academy of Sciences. At the same time, Lehr led a temporary creative team to develop the Environmental Program of Primorsky Krai, which he managed to bring to completion and offi cial approval during the collapse of the USSR. Unique documents from the Archive of the Far Eastern Branch of the Russian Academy of Sciences and the personal archive of the author are presented.

Urban Soil Dynamics: The Relationship Between Soil Health and Urbanization

Urbanization, combined with unsustainable agricultural practices, climate change, and pollution, poses a significant threat to soil health, leading to degradation with far-reaching impacts on ecosystems and human well-being. This article explores these challenges and specifically focuses on how urbanization affects soil health by degrading its quality and limiting its ability to sustain life. The study examines the dynamics of soil humification, the potential of urban soils to store carbon, and the critical impacts on food production and public health. Through a comprehensive analysis that includes geographical perspectives on soil-related issues, the article highlights innovative management strategies that can enhance the productivity and sustainability of urban soils. It emphasizes the urgent need to integrate soil science into environmental and urban planning to mitigate these negative impacts and promote a sustainable future.

Effect of Seed Treatment of Boron, Cobalt and Molybdenum on Growth Parameter, Grain Yield and Seed Quality in Soybean (Glycine max L.)

This study aimed to evaluate the effect of seed treatment of boron, cobalt and molybdenum on growth parameter, grain yield and seed quality in soybean (Glycine max L.) during kharif, during July, 2022 at experimental farm, department of Soil Science and Agricultural chemistry, College of Agriculture, Badnapur. The experiment was laid out in Randomized Block Design (RBD) with 8 treatments which were replicated thrice.The treatments comprises (T1) Absolute control, (T2) RDF, (T3) RDF + Boron @ 2 gm kg-1 seed, (T4) RDF + Cobalt @ 1.5 gm kg-1 seed, (T5) RDF + Ammonium molybdate 1 gm kg-1 seed , (T6) RDF + Boron @ 2 gm kg-1 seed + Cobalt @ 1.5 gm kg-1 seed, (T7) RDF + Cobalt @ 1.5 gm kg-1 seed + Ammonium molybdate @ 1 gm kg-1 seed, (T8) RDF + Boron @ 2 gm kg-1 seed + Cobalt @ 1.5 gm kg-1 + Ammonium molybdate @ 1 gm kg-1 seed .To achieve the objectives the observations were recorded at various growth stages of soybean kharif, during 2022. The result indicates that, treatment (T8) receiving RDF + Boron @ 2 gm kg-1 seed + Cobalt @ 1.5 gm kg-1 seed + Ammonium molybdate @ 1 gm kg-1seed was found effective due to advantages effect on morpho-physiological growth, yield and yield attributing characters likeplant height, nodulation, fresh weight of nodules, no. of root nodules, root length, number of pods plant-1of soybean grain yield, Stover yield of soybean. In grain quality the results revealed that test weight, protein content percentage were significantly influenced with the application of treatment T8. On the other hand, in all the cases the lower response was found from the control treatment.

Spatial downscaling of global soil texture classes into 30 m images at the province scale

Soil categorical data is an important aspect in soil science because it effectively facilitates communication between policymakers and stakeholders. Furthermore, soil categorical data exceeds single-property data in terms of depth of information and is an essential component of various scientific disciplines such as hydrological, ecological and pollution frameworks. However, datasets containing such information are usually too coarse for local needs and regional policies. In this study, an algorithm was introduced, known as rafikisol, to spatially downscale (to a finer detail/resolution) soil texture classes from 1 km SoilGrids images into 30 m images in three environmentally diverse provinces (Gauteng, KwaZulu-Natal, and the Western Cape) in South Africa. Rafikisol surpassed the performance of another high-resolution soil dataset (Innovative Solutions for Decision Agriculture) by 9% and 27% in Gauteng and the Western Cape, respectively (accuracy ∼75% and ∼72%). Conversely, iSDAsoil outperformed rafikisol by 34% in KwaZulu-Natal (11% accuracy). The spatial soil texture class distribution predicted by rafikisol was considerably different and heavier (clayey) in Gauteng and KwaZulu-Natal but had a similar spatial distribution with lighter (sandy) soil texture in the Western Cape compared to iSDAsoil. With improvements such as the introduction of new sampling techniques, algorithm optimization and the use of expert knowledge, this method has the potential to increase the accuracy of additional modeling frameworks that require high-resolution soil information, especially in data-scarce or resource-constrained regions. This has implications for proper land-use management, affecting aspects ranging from food security and urban expansion to biodiversity.

Detecting 3D Salinity Anomalies from Soil Sampling Points: A Case Study of the Yellow River Delta, China

Rapidly capturing the spatial distribution of soil salinity plays important roles in saline soils’ management. Existing studies mostly focus on the macroscopic distribution of soil-salinity changes, lacking effective methods to detect the structure of micro-regional areas of soil-salinity anomalies. To overcome this problem, this study proposes a 3D Soil-Salinity Anomaly Structure Extraction (3D-SSAS) methodology to discover soil-salinity anomalies and step forward in revealing the irregular 3D structure of soil-anomaly salinity areas from limited sampling points. We first interpolate the sampling points to soil voxels using 3D EBK. A novel concept, the Local Anomaly Index (LAI), is developed to identify the candidate soil-salinity anomalies with the greatest amplitude of change. By performing differential calculations on the LAI sequence to determine the threshold, the anomaly candidates are selected. Finally, we adopt 3D DBSCAN to construct anomalous candidates as a 3D soil-salinity anomaly structure. The experimental results from the Yellow River Delta data set show that 3D-SSAS can effectively identify the 3D structure of salinity-anomaly areas, which are highly correlated with the geographical distribution mechanism of soil salinity. This study provides a novel method for soil science, which is conducive to further research on the complex variation process of soil salinity’s spatial distribution.

Effect of humic acids extracted from different organic sources and inoculation with Bacillus subtilis or Aspergillus Niger on urease activity in calcareous soil

Humic substances have received a large share of research and development as amendments to poor fertility soils that are poor in fertility and have deteriorating physical properties, since the process of extracting is a common process and easy to implement, as well as diluting these acids with water enables them to be used at economically acceptable levels over large areas. It is necessary to noticed that the properties of these acids depending on the organic source and the concentration added to the soil. A laboratory experiment was conducted at the Department of Soil Sciences and Water Resources, College of Agriculture, University of Basrah ,IRAQ to demonstrate the effect of humic substances extracted from different sources and inoculation with Bacillus subtilis or Aspergillus niger on the activity of the urease in calcareous soil. Wheat straw, alfalfa leaves, goat waste and poultry waste were composted aerobically for 3 months by filling a hole of 2×2×1.5 m by layers of such waste ,turned weekly for aeration. Each pile was extracted for humic acids (humic acid + fulvic acid) . Humic acid mixed with to soil at levels of 0, 25, and 50 L h-1. The soil was also inoculated with Bacillus subtilis or Aspergillus niger isolated from local soil at rates of 20.06×106 and 40× 103 cfu ml-1, respectively The samples were incubated at field capacity level 28±2°C for 30 days. Urease activity was estimated after 7 or 30 days by determining NH4+ released using steam distillation method . A decrease in urease activity was observed when treated with different types of humic acid compared to the control treatment. The lowest activity was obtained at humic acids extracted from poultry waste, reaching 312.0 and 188.72 µg N-NH4+g-1soil.2h-1 at incubation periods of 7 and 30 days, respectively .The results also indicated that increasing the level of humic acids significantly inhibited the activity of the enzyme. However, in soil treated with Bacillus subtilis or Aspergillus niger, an increase in urease activity was observed compared to the non-inoculation treatment. Treatment with the fungal inoculant had higher activity than the bacterial inoculum, reaching 324.5 and 297.2 µg N-NH4+ g-1 soil 2 hours-1 for both inoculants at a period of 7 days, and 178.09 and 150.31 µg N-NH4+g-1soil.2h-1at a period of 30 days, respectively.It is proposed that the inhibition of urease by humic acid addition may benefit for increasing urea fertilizer efficiency.

Soil water content estimation by using ground penetrating radar data full waveform inversion with grey wolf optimizer algorithm

AbstractSoil water content (SWC) estimation is important for many areas including hydrology, agriculture, soil science, and environmental science. Ground penetrating radar (GPR) is a promising geophysical method for SWC estimation. However, at present, most of the studies are based on partial information of GPR, like travel time or amplitude information, to invert the SWC. Full waveform inversion (FWI) can use the information of the entire waveform, which can improve the accuracy of parameter estimation. This study proposes a novel SWC estimation scheme by using the FWI of GPR, optimized by the grey wolf optimizer (GWO) algorithm. The proposed scheme includes a petrophysical relationship to link the SWC with the relative dielectric permittivity, 1D GPR forward modeling, and a GWO optimization algorithm. First, numerical modeling was carried out, and the proposed scheme was applied to both noise‐free and noisy data to verify its applicability. Then, the proposed method was applied to data collected from a field experimental site. These results, derived from both synthetic and real datasets, show that the proposed inversion scheme resulted in a good match between the observed and calculated GPR data. In the numerical modeling, it was observed that the SWC could be inverted accurately, even when noise was present in the data. These demonstrate that the GWO method can be applied for the quantitative interpretation of GPR data. The proposed scheme shows potential for SWC estimation by using GPR full waveform data.

Effect of Ni and Fe Co-Application on the Soybean Crop Grown in Nickel and Iron Deficient Soils of Mirzapur District

ABSTRACT Considering the importance of nickel and iron nutrition for the soybean crop, their deficiency inhibits the yield drastically specially in the area where soybean crop is dominant. To encounter this problem, a pot experiment was conducted in glass house on low nickel and iron soil in Department of Soil Science and Agricultural Chemistry, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi, during 2019–20 and 2021–22. The study was carried out to investigate the effect of Ni (nickel) and Fe (iron) on the post-harvest soil parameters, growth, yield, nutrient uptake and nutrient content of soybean crop. There were 10 treatments with two levels of Ni (5 and 10 mg kg −1) and Fe (10 and 20 mg kg−1) with recommended dosage of fertilizers nitrogen, phosphorus, potassium (8.93, 35.71, and 17.86 mg kg−1) applied to all treatments except control. The result of the experiment revealed that the co-application of nickel and iron@10 mg kg−1 and 20 mg kg−1 (RDF + Ni10Fe20), resulted in the increase in plant height, greeness index, no of seed per pod, no of pod per plant, seed yield, and stover yield. Similar, findings for the post- harvest soil parameter indicated that there was increase in pH, electrical conductivity, and organic carbon content of soil. DTPA (Diethylenetriaminepentaacetic acid) extractable Ni, Fe, Zn, and Cu, also found highest in treatment where nickel and iron@10 mg kg−1 and 20 mg kg−1 (RDF + Ni10Fe20) were applied in soil, but in case of DTPA extractable Mn, the highest amount was found in treatment where nickel and iron@10 mg kg−1 and 10 mg kg−1 (RDF + Ni10Fe10) was applied in soil. The soil microbial biomass carbon and urease activity was also found highest in the treatment where nickel and iron@10 and 20 mg kg−1 was applied in soil. The minimum plant height, greeness index, no of seed per pod, no of pod per plant, seed, and stover yield was recorded in treatment where only RDF(T1) was applied. Similar, result recorded for the post-harvest soil parameters. So, overall findings of the pot experiment revealed that the conjoint application of nickel and iron has resulted in better yield of soybean crop.

Advancements in soil science for sustainable agriculture: conventional and emerging knowledge and innovations

Advancements in soil science for sustainable agriculture: conventional and emerging knowledge and innovations

Hydrological and pedological effects of combining Italian alder and blackberries in an agroforestry windbreak system in South Africa

Abstract. The Western Cape in South Africa is a water-scarce region which will likely receive less rainfall and higher air temperatures under projected climate change scenarios. The integration of trees within agricultural systems provides an effective measure for improving water retention on agricultural land. Studying an established and irrigated agroforestry system (AFS) combining alder (Alnus cordata (Loisel.) Duby) as a linear windbreak with a blackberry (Rubus fructicosus L.) crop, we explore the water use dynamics of the intercrop as influenced by the windbreak element by combining methods from hydrology, soil science and forestry disciplines. Our objective is to explore whether the AFS positively impacts the water balance by combining measurement campaigns to characterise the spatial variability of various key system properties with continuous monitoring. The campaigns encompassed extensive soil sampling to determine soil characteristics (nutrient concentrations, hydraulic conductivity, texture, water retention) in the laboratory as well as terrestrial laser scans of the field site, especially of the windbreaks. The continuous measurements covered meteorological, soil water content and soil water potential observations over a 6-month period (in summer). These were applied to understand soil water dynamics during rainstorms and dry spells, including root water uptake as well as soil water storage. We recorded a total of 13 rainfall events delivering 2.5–117.6 mm of rainfall with maximum intensities of 4.1 to 82.6 mm h−1. Further analyses showed that infiltration is likely dominated by preferential flow, with root water uptake potentially occurring in two depth zones corresponding to different plant communities. While soil water content varied by depth and was influenced by physical and environmental factors, it was generally higher in the intercrop zone than within the windbreak-influenced zone. During dry spells, soil water content did not drop below the water content of the permanent wilting point (<-1500 kPa). Values corresponding to soil water tensions above 1000 kPa were recorded on several occasions; these were mitigated by irrigation and, thus, did not result in water stress. Nutrient distribution and soil physical properties differed near the windbreak in comparison to the blackberry crop, and the carbon sequestration potential is great in comparison to monoculture farming. We could demonstrate positive effects of the windbreak on the water balance and dynamics in the blackberry field site, even though questions remain as to the extent of these benefits and how they compared to disadvantageous aspects brought about by the presence of the trees (e.g. increased water usage). Irrigation did, in fact, shift the AFS from a water-limited regime to an energy-limited one.

Global Trends and Current Advances in Slow/Controlled-Release Fertilizers: A Bibliometric Analysis from 1990 to 2023

Slow/controlled-release fertilizers (SRFs/CRFs) occupy a critical position in agricultural advancement, enhancing productivity and sustainability by regulating nutrient release, improving fertilizer efficiency, reducing pollution, and promoting lasting agricultural progress. To attain an in-depth understanding of the current landscape, hotspots, and development trends in SRF/CRF research, this study employed the Bibliometrix toolkit in R, VOSviewer, and CiteSpace for the statistical and graphical analysis of pertinent literature in the Web of Science Core Collection (WOSCC) database from 1990 to 2023. In this study, several dimensions were evaluated to assess the research scope and impact, including the quantity of published articles, authorship, citation frequency, keywords, institutional affiliations, publication journals, and source countries. The results indicate a significant increase in scholarly publications related to SRFs/CRFs from 1990 to 2023, totaling 1676 published papers across 77 subject categories. Research activities spanned 69 countries/regions, with China and the USA leading contributions. A total of 1691 research institutions published on SRFs/CRFs, with the University of Florida, the Chinese Academy of Sciences, and China’s Shandong Agricultural University being preeminent. HortScience, Science of the Total Environment, and Communications in Soil Science and Plant Analysis were the top three journals. Keyword co-occurrence and burst analysis disclosed that current research primarily focuses on several key areas: nitrogen (N) use efficiency, the processes of nitrification and denitrification, degradation, the use of phosphate (P) fertilizers, urea, and factors affecting crop growth and quality. The findings revealed several critical areas and trends within the sphere of SRFs/CRFs, with future research specifically directed towards developing cost-effective, efficacious, and environmentally friendly alternatives. Furthermore, future progress will concentrate on addressing the enduring environmental ramifications of SRF/CRF utilization.

Integrated Manure and Fertilizer Application: A Pathway to Enhanced Rice Yield and Soil Health

A research study was carried out in the Soil Science field laboratory of Bangladesh Agricultural University, Mymensingh during the Aman season of 2021 to examine the effect of various manure and fertilizer combinations for optimizing the growth and yield of rice. The experiment employed a Randomized Complete Block Design (RCBD) with 3 replications across eight treatments. The treatment combinations were: T­1 (Control), T2 (100% Recommended Fertilizer Dose (RFD)), T3 (75% RFD + Cowdung (CD) @ 5 t ha-1), T4 (75% RFD + Poultry manure (PM) @ 3 t ha-1), T5 (75% RFD + Compost @ 5 t ha-1), T6 (75% RFD + Dhaincha Green Manure (GM) @ 10 t ha-1), T7 (50% RFD +CD @ 2.5 t ha-1 + PM @ 1.5 t ha-1) and T8 (50% RFD + Compost @ 2.5 t ha­-1 + Dhaincha GM 5 t ha-1). Statistical analysis conducted using R programming revealed that T6 markedly improved growth metrics and yield-related traits, leading to a 12.2% rise in grain yield and a 13.24% rise in straw yield compared to T2, where only chemical fertilizers were applied. This treatment also achieved the greatest macronutrient content and uptake, outperforming other treatments (T3, T4, and T5) with equal nutrient amounts. Therefore, application of 75% recommended fertilizer dose along with dhaincha green manure (10 t ha-1) offers a promising strategy for successfully cultivating BRRI dhan71 with a good soil health. This approach offers farmers a cost-effective method to boost productivity and support long-term soil fertility, and policymakers could promote it to enhance agricultural sustainability.

RUSSELL REVIEW Soil carbon stewardship: Thinking in circles

AbstractThe words we choose to describe our research ultimately directs its course. A dominant term in soil science now, is ‘sequestration’, referring to the removal of carbon (C) from air and its irreversible seclusion in soil, ideally as stable soil organic carbon (SOC). An emerging view, however, now sees SOC as an inherently dynamic assemblage of forms, all potentially vulnerable to decay, with no discrete, measurable fraction holding C in ‘sequestered’ form. Rather than speaking of C ‘sequestration’, then, we might refer instead to SOC ‘stewardship’. This word, now, enfolds the entire spectrum of SOC, not merely some elusive ‘persistent’ or ‘stable’ fraction, perhaps redirecting inquiry; for example, does C need to be ‘sequestered’ in stable form for SOC to serve as effective repository of excess atmospheric CO2? ‘Stewardship’ explicitly accepts the relentless turnover of SOC, emphasizing the need to manage not only fixed stocks of C, but also the cyclical flows of C through ecosystems that drive their functions. Among other benefits, ‘stewardship’ might motivate us to consider all functions of SOC (not only climate mitigation), consider the entire C cycle (not only enhancing soil C), and preserve existing troves of SOC (not only augmenting them in selected places.) Perhaps most fundamentally, by its etymology, ‘stewardship’ poses a compelling, timeless question: for whom do we steward SOC? Asking why look after SOC, not only reflects our own underlying quest for resilience, but also expands our potential audience and entices the more creative minds that must succeed us. Although ‘stewardship’ may elicit new and fruitful inquiry, we may need to look for words even more evocative, more alluring, more true to our mandate of living well within the circling C that must always sustain us.

How meeting the ten pedometrics challenges can deliver healthy‐soil contributions to SDG‐related ecosystem services

AbstractWhen considering ecosystem services in line with relevant Sustainable Development Goals, the proposed logical sequence of the ten pedometric challenges can form a framework defining effective contributions by the soil science discipline to the sustainability challenge facing society. Defining relatively simple, but scientifically sound, indicators and thresholds for ecosystem services can be the basis for a transparent regulatory system justifying payment for ecosystem services provided to society. The current serious lack of trust between the policy and farming arenas can and should be restored by scientists and farmers working jointly in Living Labs, aiming to become Lighthouses, to be part of Communites of Practice (CoP). A Living Lab case study is reviewed showing that much know‐how is already available to define indicators and innovative cutting‐edge methodology adds attractive new opportunities for rapid and relatively cheap characterizations. Field work remains essential and just routinely applying standard techniques fed by existing databases may lead to poor results. Research on indicator‐thresholds has a high priority. In the case study, the important soil fertility indicator was based on the current procedure of field sampling and fertilization recommendations by specialized agencies, that is already followed by 85% of farmers. This could be expanded by including indicators for other ecosystem services thereby contributing substantially to the societal sustainability debate. Soil health plays a key role when contributing to all ecosystem services. Showing this with specific examples in a Living Lab/Lighthouse and CoP context is the best way to promote the profession which is needed to justify current major funding. Not only cutting‐edge research can contribute to defining indicators and thresholds. A hundred years of research has produced many valuable insights and methodologies that can be applied as well. The: ‘better’ can be the enemy of the: ‘good’. The sustainable development challenge is highly urgent: there is no time to lose.

How to focus soil research when contributing to environmental agricultural regulations aimed at sustainable development

AbstractCurrent environmental regulations for agriculture in the Netherlands and England focus on the application of certain selected management measures as an empirical basis for providing subsidies. Farmers like this simple, straightforward approach. The link with sustainable development is, however, not defined and this can become problematic when procedures may be challenged in future. A procedure focusing on the measurement of ecosystem services in line with selected UN Sustainable Development Goals (SDGs) can provide this link, but whether or not this more complicated procedure will be attractive for farmers is still unclear. The soil science community would be well advised to discuss their future role in developing scientifically sound operational procedures that would be acceptable to both farmers and policy makers and would be aimed at contributing to the sustainable development of society at large.