A proof-of-concept environmental indicator framework designed to monitor soil health and its capacity to deliver key ecosystem services was developed for England. The framework addressed trade-offs inherent in managing soils for diverse, often conflicting outcomes, such as climate regulation, food production, water regulation, and below-ground biodiversity. By integrating these ecosystem services into a unified system, the framework enables assessment of soil health at a granular scale while contextualizing results across broader land uses.Key soil properties critical to soil health and ecosystem service delivery were identified and ranked, forming the basis of conceptual models for statistical modelling in Bayesian Belief Networks. These models were populated with national-scale datasets and expert judgment, providing probabilistic outputs that indicated the capacity of soils to support ecosystem services at the land parcel level. Results were visualized in a user-friendly dashboard app, allowing for comparison of soil health within the context of inherent soil properties and current land use.Initial outputs demonstrated the utility of the framework in identifying trade-offs and synergies between ecosystem services, while also potential to detect emergent soil system properties. The framework’s flexibility has allowed for further iterative refinement of the models, and future incorporation of local knowledge, new soil data, and adjustment to evolving policy or scientific understanding. This adaptability ensures the framework remains relevant for diverse applications, from reporting national policy targets on soil health to supporting field-level decisions by farmers.

Calcareous grasslands are important biodiversity sites and among Europe’s most floristically rich habitats. These habitats are, however, threatened; many of the UK’s calcareous grasslands were lost to changing land use during the 20th century and pressure on the surviving (often fragmented) sites persists. Due to their ecological value and threatened status there is significant interest in restoring and creating new areas of calcareous grassland, and an increasing number of projects are working to restore or re-create these internationally important ecosystems. A major calcareous grassland creation project in the Colne Valley in the UK is being undertaken as part of the Central 1 section of the HS2 (High Speed 2) Phase One rail development, delivered by the Align joint venture. This will form a large area (90 hectare) of calcareous grassland as part of a larger (127 hectare) mosaic habitat including wood pasture and wetlands on former low-grade arable land subsequently used for construction. This represents the largest single area of habitat creation along the HS2 route and will significantly contribute to the project’s commitment to deliver ‘No Net Loss’ in biodiversity. To create soil profiles suitable for supporting species-rich calcareous grassland by-products from the HS2 development will be used; this will combine sustainable re-use of construction materials with the development of novel ways to create or restore chalk grassland habitats. These materials include 2.6 M m3 of excavated chalk from 16 km of tunnel construction, crushed limestone and concrete from decommissioned compounds/haul roads, and subsoils (stripped during site clearance). However, how to best create soil profiles to support calcareous grassland habitat creation, including the potential for re-use of construction by-products, is not well understood. Success depends on establishing the specialised soil physical, chemical and biological environment required to support the diverse calcareous grasslands plant communities, including suitable soil structure, infiltration capacity and nutrient levels. We have therefore tested constructed soil profiles using different configurations of site-derived materials / construction by-products, using numerous soil and plant metrics through a combination of controlled environment and field trials to assess their ability to support calcareous grassland creation. Here we present results from the main large-scale, controlled-environment trial at Cranfield University, in which we tested four soil profile configurations and the effect of upper soil layer depth in large (1 m3) soil mesocosms. The development of calcareous grassland on these profiles was closely monitored over a six-month period, including above- and below-ground imaging to monitor sward and root development, alongside close monitoring of soil hydrology, microbial dynamics, nutrient cycling, and vegetation establishment and diversity. This included a simulated drought period to assess how soil profile configurations affected the developing grassland vegetation’s resistance to water stress. Our results provide a uniquely high-resolution examination of how constructed soil profiles can be used to support calcareous grassland establishment and how profile design affects the ability of restored grassland to withstand environmental stress. This will allow improvements in circular re-use of infrastructure construction by-products in habitat restoration and development of novel strategies for the (re-)creation of biodiverse habitats.

Biostimulants are gaining prominence in scientific research, with the potential to enhance plant productivity through benefits to crop yield/quality and tolerance to environmental stresses. Through possible improvements to nutrient use efficiency, they may also lessen the adverse environmental impacts of conventional inorganic fertilizer use in agriculture. The application of biostimulants is currently uncommon as a farming practice, with uncertain effectiveness in delivering these potential benefits. Current research focuses on biostimulant effects on plant physiological changes. There is little scientific evidence on the impact of biostimulants on soil properties (biological, physical, or chemical) or soil functions. This knowledge gap should be addressed considering the vital role of soil processes in the bioavailability of nutrients, as reflected in crop productivity. This review evaluates laboratory and field experimental work on the effectiveness of common, non-microbial biostimulants, with a focus on their modes of action within the soil matrix. Of 2,097 initial articles returned through the search strings, 10 were within the scope of this review. A common soil biostimulant mechanism emerges from this literature. This relates to the supply of nutrients provided by the biostimulants, which stimulate native soil microbiology in mineralizing organic material in the soil, thus producing more bioavailable nutrients for plant uptake. Additionally, some articles link biostimulant effects to soil physical and chemical changes, which in turn impact soil biology (and vice versa). However, there is inconsistent evidence to provide full support for these explanatory mechanisms. This review highlights the need for further research into the effect of biostimulants on the native soil microbiology and associated soil properties, to provide greater clarity on biostimulants’ modes of action and greater mechanistic insights into how they can be used to improve crop production.

Soil erosion is a result of detachment and transport of particles or small aggregates from the soil surface. Previous research has predominantly focused on studying the effects of either rainfall or wind on soil erosion processes as separate erosive agents. To date, there have been only few studies into the simultaneous effect of both agents operating at the same time on soil erosion and hydrological processes. In this research, the effect of wind velocities on the erosivity of rainfall was studied, comparing windless rain (WLR) and wind-driven rain (WDR) events when applied to a sandy loam soil. A moderate slope gradient of 11%, a simulated rainfall intensity of 90 mm hr-1, a rainfall duration of 30 minutes and wind velocities up to 9 m s-1 were used. The runoff, infiltrate and soil loss (including splash erosion measured at different heights) were compared between the different events and treatments. The soil surface roughness was measured before and after the rainfall event, using a hand-held laser scanner, to evaluate the effect of WLR and WDR on the surface morphology. The outcome of this study shows that, for the smooth surface under WDR, infiltrate volumes were less than under WLR and decreased with increasing wind velocity, while the runoff volumes increased under WDR compared with WLR. The rate of rainsplash erosion increased under the WDR event compared to the WLR event at all heights. The amount of splash-eroded particles decreased with height above the soil surface. We conclude that wind has an effect on the erosivity of rainfall; therefore, it should be considered in erosion studies.Acknowledgments: This work was funded by OCP group, Morocco

The agricultural sector faces multiple challenges linked to increased climate uncertainty, causing severe shocks including increased frequency of extreme weather events, new pest and disease risks, soil degradation, and pre and postharvest food losses. This situation is further exacerbated by geopolitical instability and volatility in energy prices impacting on fertiliser supplies and production costs. Net zero strategies are vital to achieve both food security and address negative environmental impacts. This perspective paper reviews and assesses the most viable options (actions) to achieve net zero with a focus on the arable/livestock and protected cropping sectors in the UK. The methodology was based on a synthesis of relevant literature, coupled with expert opinions using the holistic PESTLE (Political, Environmental, Social, Technological, Legal and Environmental) approach to categorise actions, leading to formulation of a roadmap to achieve net zero. The PESTLE analysis indicated that there are technically and economically viable actions available which need to be prioritised depending on the ease of their implementation within the two crop sectors investigated. These actions include (i) policy changes that are better aligned to net zero; (ii) circular economy approaches; (iii) connectivity and accessibility of information; (iv) increased resilience to shocks; (v) changing diets, nutrition and lifestyles; (vi) target setting and attainment; and (vii) farm economics and livelihoods. The outputs can be used by stakeholders and decision makers to inform policy and drive meaningful changes in global food and environmental security.

Soil hydraulic properties are an important factor to optimize and adapt water management for a given crop. Pedotransfer functions (PTFs) present a solution to predict soil variables such as hydraulic properties, using fundamental soil properties. In this research, we compared two sources of soil information: iSDAsoil data and field data, in four regions in Morocco. We then used this data to evaluate published data and developed new PTFs using soil information to estimate soil gravimetric moisture content at saturation ( w 0 ), field capacity ( w 330 ) and permanent wilting point ( w 15000 ). A total of 331 samples were collected from four regions: Doukkala, Gharb-Loukous, Moulouya and Tadla. The data was divided into calibration and validation datasets. For development of different PTFs, we used simple linear regression, multiple linear regression, regression tree, Cubist algorithm, and random forest approaches. PTFs developed by Dijkerman (Geoderma, 1988, 42, 29–49) presented the best performance, showing lower RMSE, Bias and MAE compared to other PTFs. Using multiple linear regression to develop PTFs, models based on clay, silt and soil organic matter as input variables showed the best performance after calibration (R 2 of 0.590, 0.785, 0.786 for w 0 , w 330 , and w 15000 , respectively). Regarding the techniques based on machine learning, random forest showed the best performance after calibration compared with other algorithms (R 2 of 0.930, 0.955, 0.954 for w 0 , w 330 , and w 15000 , respectively). PTFs represent a low cost and easy technique to estimate soil hydraulic properties, to improve water management efficiency for the farmers.

Soil erosion is the detachment and transport of slope forming materials by erosive agents. Rates of water-induced soil erosion are determined by interactions between rainfall and runoff, soil type, slope steepness and length, vegetation and land management. As soil is lost through the processes of sheetwash, rill and gully erosion, vital ecosystem goods and services delivered by soils are compromised. The impacts of this justify the use of erosion control measures, which include agronomic methods (the use of vegetation or simulated vegetation); mechanical methods (the use of field engineering structures); and soil management methods (the improvement of soil conditions).

Purpose Studies predicting the impacts of climate change on erosion have considered numerous variables, such as rainfall erosivity and vegetation cover, but have not considered potential changes in soil erodibility. Erodibility is an intrinsic property of the soil, strongly correlated with the stability of soil aggregates. It is influenced by soil physico-chemical attributes, including the microbiological community. The study aim was to determine how shifts in temperature and moisture conditions, which other studies have shown affect microbiological communities, might affect aggregate stability. Methods Using an experimental approach with laboratory microcosms, aggregates from a sandy loam soil and a clay soil were incubated at three temperatures and three moisture conditions in a factorial experimental design. Aggregate stability was quantified using rainfall simulation. Microbiological indicator metrics were measured to evaluate treatment microbiological impacts, including community composition (PLFA), biomass carbon, and respiration. Results Temperature and moisture content affected aggregate stability significantly, but differently for the two soil types tested. For the sandy loam soil, aggregate stability decreased significantly with increasing moisture content. For the clay soil, aggregate stability increased significantly with increasing temperature. For both soil textures, temperature and moisture content affected microbiological community composition and respiration. Regression analysis indicated that microbiological properties were significant predictors of aggregate stability. Conclusion Our results emphasise the dynamic nature of soil aggregate stability. Changes in microbiological metrics suggest possible biological mechanisms for aggregate stability changes, which should be investigated further to better understand the potential impacts of climate change on soil erodibility and erosion.

Soil erosion by water is a result of detachment of particles or small aggregates from the soil surface followed by transport of the detached material. One of the elements that affects surface runoff and soil erosion is the soil surface roughness (SSR). Prior research reports that increasing SSR reduces generation of runoff and soil loss. In addition to that, it is widely reported that across-slope oriented roughness is better at controlling soil and water losses. However, to date there have been few studies into the effect of both magnitude and orientation of SSR on runoff, infiltration and soil erosion at the sub process level (i.e. by raindrop splash and overland flow), occurring simultaneously. In this study, the effects of up-down-slope oriented SSR (Treatment A), across-slope oriented SSR (Treatment B) and random SSR (Treatment C) were compared, along with a smooth surface (Treatment D). A moderate slope gradient of 10 %, a simulated rainfall intensity of 90 mm hr-1 and storm durations of 15 or 30 min were considered. The SSR was measured using the chain method, before and after the rainfall event. Images of the soil surface were taken using a hand-held laser scanner to monitor the effect of rainfall on the surface morphology. The outcome of this study shows that rainfall erosivity increases the SSR of the initially smooth surface, but decreases that of the initially rough surface, particularly in the random SSR treatment, where the decrease in SSR was 64 % of the pre-rainfall condition. This was due to the effects of raindrop impacts and overland flow. The random SSR treatment generated significantly more runoff and soil loss, and less infiltration than all other treatments (p < 0.001), but for raindrop splash erosion, there was no significant difference be-tween random SSR and the other treatments. Contrary to expectations, the across-slope oriented SSR did not always reduce runoff and soil erosion compared to the up-down-slope orientation. This can be explained by degradation of surface microtopography by rainfall and runoff, as confirmed by the post-rainfall SSR measurements.

Soil erodibility is the susceptibility of soil to the erosive forces of rainsplash, runoff and wind. It is a significant factor in determining present and future soil erosion rates. Focusing on soil erosion by water, this chapter shows that erodibility is determined by static and dynamic soil properties that control a range of sub-processes affecting soil erosion, but there is no standardised test procedure, making comparison of erodibility assessment techniques and their results challenging. Most researchers agree that aggregate stability is the best indicator of soil erodibility. Selection of techniques to measure aggregate stability need to consider the type of disruptive forces and breakdown processes to which field aggregates are subjected. New indices must incorporate spatial and temporal variabilities in erodibility; the different erosion processes operating; the impact of climate change; and the role of soil biology. New analytical techniques such as computer aided tomography show promise in considering soil erodibility as a dynamic continuum operating over 3 dimensions.

Agricultural phosphate (PO43-) is a major cause of water quality compliance failures. Filter socks (FS) are a sediment-control method proven to be effective at removing sediment and sediment bound-P. Within the water and wastewater treatment industries phosphorous sorbing materials (PSMs) are widely used to remove reactive PO43-. Combining PSMs with FS provides an opportunity to concomitantly remove sediment, sediment bound-P and PO43- from agricultural runoff. A column experiment was undertaken to evaluate the efficacy of selected PSMs to remove PO43- across a range of PO43- concentrations (0.08, 0.26 and 1.3 mg/L) and contrasting FS fill media (PAS 100 Compost and Woodchip). The results indicate that Ca-enriched ferrihydrite removed up to 99% of PO43-, and was the only PSM to reduce PO43- to below the target value of <0.05 mg/L. An initial cost-benefit analysis indicates that PSM-enhanced FS are a viable option to remove PO43- from agricultural runoff.

Interactions with soil microbes can strongly affect plant growth and defense against aboveground herbivores. Plant species often accumulate specific soil pathogens in their rhizosphere, leading to reduced growth of plants in soils originating from stands of conspecific plants compared to soils from heterospecific plants. However, whereas effects of such conspecific vs. heterospecific soil biota on plant growth have been well documented, their effects on plant resistance and tolerance to aboveground insect herbivores have not. We compared growth and defense of Triadica sebifera plants from populations where the species is native (China), when grown in sterilized soils, or in soils harbouring belowground biota from conspecific (native Triadica) or heterospecific (native grass) soils. In each of these soils, plants were exposed to a 15-day period of foliar herbivory by a specialist weevil (Heterapoderopsis bicallosicollis), a specialist caterpillar (Gadirtha inexacta), or no herbivory (cage), followed by a 60-day recovery period. Soil biota from conspecific and hetetospecific soils differed in their effects on plant growth and defense. First, in the absence of herbivory, soil biota from heterospecific soils slightly enhanced plant growth, whereas those from conspecific soils strongly reduced plant growth. Second, soil biota from conspecific soils strongly affected plant resistance and tolerance to foliar herbivory, whereas soil biota from heterospecific plants did not. The effects of soil biota on plant defense were herbivore-specific. In particular, conspecific soil biota reduced resistance to caterpillar but not to weevil feeding, whereas they enhanced tolerance to weevil but not to caterpillar feeding. Conspecific soil biota also mitigated induction of root flavonoids by herbivores and led to reduced root phenolics in response to herbivory. Conversely, caterpillar feeding increased AMF colonization, but under these conditions, AMF colonization was negatively associated with plant biomass. In addition to testing effects on native plants, we also tested effects of native soil biota on growth and resistance of plants from the introduced range (North America). Plants from the introduced range had higher shoot production, shoot-to-root ratio, and leaf phenolic and flavonoid production than plants from the native range, but their interactions with soil biota showed only minor differences compared to plants from the native range. Our results suggest that incorporating the effects of soil biota in interactions between plants and foliar herbivores is critical for understanding variations in growth, defense, and performance among plant populations at local and broader geographic scales.

Grassed waterways are used to mitigate the offsite transport of sediment generated by soil erosion. This study used a novel trait-based ranking approach as a method to screen potential candidate grass monocultures and mixes based on their theoretical performance in reducing (a) detachment via rainsplash, (b) detachment via scouring due to concentrated flow and (c) sediment transport and deposition processes. Selected grass species were grown under simulated UK summer and autumn establishment conditions under three different replicated rainfall scenarios: drought, normal rainfall and excess rainfall. The grass species used were the novel hybrid species Festulolium cv Prior (Fest_1) and Festulolium Bx511 (Fest_2) and a conventional mixture of Lolium perenne and Festuca rubra (Conv). Monocultures and mixtures of these species were studied. Plant traits pertinent to control of soil erosion by water were measured. Aboveground traits included plant height, percentage ground cover, aboveground biomass, stem diameter, stem area density and number of tillers. Belowground traits included total root length, root total surface area, belowground biomass, root diameter and % fine roots <= 0.25 mm. For summer conditions, the species treatments that had the highest overall soil erosion mitigation potential were Conv, Fest_1 + 2 + Conv and Fest_2. For autumn conditions, the best treatments were Fest_1 + 2, Fest_1 + 2 + Conv and Conv. The Fest 1 + 2 + Conv had more desirable traits for erosion control than mono Festulolium treatments for the autumn conditions. The conventional mixture had more desirable traits for erosion control than mono Festulolium treatments in both climate scenarios. The results indicate that the trait-based ranking approach utilized in this study can be used to inform rapid screening of candidate grass species for soil erosion control. Highlights How to select the most suitable grass species for soil erosion control under changing climate conditions? A novel scoring system based on plant traits associated with soil erosion mitigation was developed. Fest_1 + 2 and Conv treatments expressed traits strongly associated with maximum soil erosion mitigation. Species selection for grassed waterways should consider the establishment growing season and expected rainfall.

The effects of five conservation tillage drills with crop residue levels covering between 17% and 79% of the soil, and tillage depths ranging from 25 to 200 mm, were examined over 3 years. The tillage systems ranged from a relatively disruptive Farm System to a Low Disruption system, with three intermediate treatments labelled Sumo DTS, Claydon and Mzuri. The study involved field sites on a clay or clay loam soil, where winter wheat and oilseed rape were grown in rotation. In the clay field, the Mzuri and Low Disruption treatments, which produced the highest residue coverage, showed the greatest increase in surface total soil organic carbon (1.1 and 0.48 Mg C ha−1, respectively) between years 1 and 3. The least disruptive tillage system also resulted in the highest density of earthworms (181–228 m−2), and the most disruptive system produced the lowest densities (75–98 m−2). In the third year, the least disruptive system also showed a higher proportion of water‐stable aggregates (29.8%) than the other treatments (22.7%–25.3%). Linear regressions showed positive relationships of both soil organic carbon and earthworm density with surface residue cover, and of the proportion of water‐stable aggregates with soil organic carbon.

Accelerated soil erosion can result in substantial declines in soil fertility and has devastating environmental impacts. Consequently, understanding if rates of soil erosion are acceptable is of local and global importance. Herein we use empirical soil erosion observations collated into an open access geodatabase to identify the extent to which existing data and methodological approaches can be used to develop an empirically-derived understanding of soil erosion in the UK (by way of an example). The findings indicate that whilst mean erosion rates in the UK are low, relative to the rest of Europe for example, 16% of observations on arable land were greater than the supposedly tolerable rate of 1 t ha(-1) yr(-1) and maximum erosion rates were as high as 91.7 t ha(-1) yr(-1). However, the analysis highlights a skew in existing studies towards locations with a known erosion likelihood and methods that are biased towards single erosion pathways, rather than an all-inclusive study of erosion rates and processes. Accordingly, we suggest that future soil erosion research and policy must address these issues if an accurate assessment of soil erosion rates at the national-scale are to be established. The interactive geodatabase published alongside this paper offers a platform for the simultaneous development of soil erosion research, formulation of effective policy and better protection of soil resources.

Grassed waterways reduce water runoff, prevent scouring and encourage sediment deposition from erosion prone land. The aim of this study was to assess the efficacy of conventional and novel grass species (as monocultures and mixtures) to control erosion, at an early establishment stage (6 weeks), within grassed waterways. The experimental treatments included bare soil (B), a conventional mix of Lolium perenne and Festuca rubra (C), Festulolium cv prior (F1), Festulolium cv prior and Festulolium bx511 (F1+F2), and all grass species combined (F1+F2+C). F1 is adapted to flooded conditions, whilst F2 is adapted to drought conditions. With climate change in the UK likely to result in drier summers and wetter winters these Festulolium species will be adapted to future climatic conditions. However, little is known about their efficacy within grassed waterways. The grasses were established in 1.2 x 1 x 0.5m macrocosms in a sandy clay loam soil during June-Aug, 2019. A sub sample of each experimental treatment was taken (0.3 x 0.1 x 0.1m) from the macrocosms within a stainless steel box. Tests were replicated in quadruplicate. The following above ground trait (Stem area density) and the following below ground traits (Total root length of fine roots <0.25mm, root diameter and root surface area) were determined for each experimental replicate. Prior to testing, the grass was cut to circa 3.0 cm height to represent a mowed grass sward before being placed into a fully instrumented hydraulic flume. The hydraulic flume simulated a concentrated flow event and treatment performance was assessed in terms of turbidity, sediment concentration, soil loss and flow velocity. The effects of roots+shoots and of roots only on performance indicators were determined to quantify the relative contribution of above ground vs below ground traits in controlling erosion. One set of replicates was tested only with roots whilst another set of replicates was tested with roots+shoots and then with roots only. This was done to isolate the effect of below ground and above ground traits. All replicates were subjected to a concentrated flow event with increasing incremental flow velocities from 0.2-0.6l s-1 for bare soil, 0.2-0.8l s-1 for roots+shoots treatments and 0.2-1.4l s-1 for roots only treatments. Each flow rate velocity was run for 60 seconds. For each flow rate, duplicate water samples were taken downslope of the treatment and water depth was measured, upstream of the treatment, in the centre of the treatment and downstream of the treatment. The water samples were used to determine sediment concentrations. The water depth measurements were used to determine runoff velocity. Furthermore, a turbidity meter continuously measured turbidity during the concentrated flow event. Soil detachment and transport rates were significantly reduced for all experimental treatments as compared to the bare soil (p<0.05). Final treatment efficacy will be assessed based on a ranking of the key performance indicators. The knowledge gained from this research can be used and applied to other grassed soil erosion mitigation features such as in field and riparian buffer strips, swales as well as grassed waterways.

Soil is a critical resource that delivers numerous ecosystem services, yet this capacity is diminished by soil erosion and further threatened by the impacts of climate change. Soil erodibility is largely overlooked when considering soils’ response to climate change. Aggregate stability is widely recognised as a key indicator of soil erodibility and is influenced by multiple physical, chemical and biological mechanisms operating simultaneously. The microbial community has been reported to respond to changing climatic conditions, yet it remains unclear how microbial change influences microbially mediated aggregation and therefore aggregate stability. The microbial community in terms of composition, activity, and growth, can change over rapid timescales in response to climate conditions. The short timescale of such microbial shifts could rapidly impact microbially-mediated soil (de)stabilisation and aggregate stability.The aim of this work is to experimentally test whether climatic conditions, in terms of temperature and moisture content, influence the microbial community and microbially-mediated soil (de)stabilisation, in turn influencing aggregate stability and soil erodibility. A series of laboratory-controlled experiments using environmental chambers and rainfall simulation examined the effects of temperature and moisture content in both static and fluctuating treatments on two surface soils (a sandy loam and a clay loam). Treatments were conducted with single layer aggregate microcosms and multi-layered soil trays to explore aggregate-scale mechanisms and the potential upscaling to run-off processes.Key findings from this research demonstrate that temperature and moisture content affect aggregate stability and the importance of climate induced microbial shifts influence on microbially mediated soil (de)stabilisation. Static temperature and moisture content conditions significantly affected aggregate stability, however the effects varied dependent on soil texture. Increasing temperature significantly increased aggregate stability in clay loam aggregates, while moisture content significantly decreased aggregate stability in sandy loam aggregates. Multiple regression analysis showed that aggregate stability was best predicted by soil moisture content, microbial biomass carbon, gram-negative bacterial abundance and fungal abundance in the sandy loam. Temperature was the sole significant predictor in the clay loam. Aggregate stability was significantly lower under fluctuating conditions and higher under static conditions. Aggregate stability was not significantly different between fluctuating climate treatments representing summer and winter cycles under future emission scenarios. Although, these treatments did significantly affect the microbial community. Our results have implications for our current understanding of microbial function in terms of soil stabilisation, and the relationship between climate, aggregate stability and soil erodibility.

In the UK, conventional asparagus cultivation practices on sloping land, erodible soils and increased frequency of extreme rainfall events combine to promote runoff generation and soil loss, particularly from interrows. This instrumented field study investigated the interactive effect of mulch and shallow soil disturbance (working depth of 0.175 m) on reducing runoff and soil loss. Ten treatments were installed in a commercial asparagus field near Ross-on-Wye (England, UK) during May 1st-July 17th, 2012. Straw and compost were applied to the interrows at high and low application rates (straw = 5 t ha(-1) and 3 t ha(-1) and compost = 18 t ha(-1) and 8 t ha(-1), respectively), both with or without shallow soil disturbance (SSD and Non-SSD) as compared with a bare soil, unamended Control. Across five sampling periods, Non-SSD straw mulch applied at 5 t ha(-1) and 3 t ha(-1); NonSSD compost mulch at 18 t ha(-1); and straw mulch applied at 5 t ha(-1) with SSD all significantly reduced cumulative total soil loss by 53-72% as compared with the Control. Further, mulch treatments with SSD were in general less effective at reducing total soil loss as compared to non-SSD mulch treatments. Compost application was less effective than straw, due to sub-optimal compost blanket depths as dictated by N restrictions for Nitrate Vulnerable Zones, in which the study took place. Despite an overall reduction in total soil loss of 72% (associated with Non-SSD straw mulch applied at 5 t ha(-1)), soil erosion rates exceeded 1.4 t ha(-1) yr(-1), considered to be a tolerable erosion rate in the EU. In addition, measured sediment concentrations in the runoff consistently exceeded the EU water quality guideline value of 25 mg l(-1)( )The results indicate that the efficacy of the treatments tested was not adequate to reduce soil erosion in commercial asparagus fields in the UK to tolerable rates. This may in large part be due to daily foot trafficking events that occur during the asparagus harvesting period (April-June) which disturbs and degrades the treatments applied reduing their efficacy. This study demonstrates that additional research is required in order to identify effective erosion control measures to ensure the sustainability of commercial asparagus production systems in the UK.

Five conservation tillage treatments were applied to an alternating rotation of wheat (Triticum aestivum L.) and oilseed rape (Brassica napus L.) within neighboring clay and clay loam fields in the United Kingdom over three cropping seasons (2013 to 2016) with the objective of determining how the treatments affect soil physical characteristics, weed control, and crop yields. The conservation tillage systems included a relatively disruptive “Farm System” with cultivation to a depth of 200 mm, three intermediate treatments, and a “Low Disruption” treatment with cultivation to a depth of 25 to 100 mm. The disruptive Farm System showed the greatest increase in soil porosity immediately after tillage and resulted in higher wheat and oilseed rape plant counts than the other treatments. Each tillage treatment resulted in mean soil penetration resistances below 2.5 MPa, although a tillage treatment with tine depth to width ratio of 7.5:1 resulted in a higher resistance (2.14 MPa) at 150 to 200 mm than three other treatments (1.36 to 1.67 MPa) in year 1. Despite the above differences, the five tillage systems resulted in statistically similar wheat and oilseed rape yields, except when there was a delay in applying one treatment to the oilseed rape in year 3. In the first two years, the yields of wheat in the clay (9.7 to 10.6 t ha−1) and the clay loam field (11.0 to 11.6 t ha−1) were similar to yields on other commercial farms. However, in year 3, the wheat yield on the clay soil declined to 8.7 to 9.5 t ha−1. Some of this is a result of low levels of solar radiation in 2016, but the levels of blackgrass (Alopecurus myosuroides Huds.) increased from 8.2% to 16.0%. There was no statistically significant difference between the capacity of the conservation till-age treatments to control blackgrass on the clay soil, indicating that other measures are needed to control this competitive weed.