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Grasslands cover a significant proportion of the agricultural land within the UK and across the EU, providing a relatively cheap source of feed for ruminants and supporting the production of meat, wool and milk from grazing animals. Delivering efficient animal production from grassland systems has traditionally been the primary focus of grassland‐based research. But there is increasing recognition of the ecological and environmental benefits of these grassland systems and the importance of the interaction between their component plants and a host of other biological organisms in the soil and in adjoining habitats. Many of the ecological and environmental benefits provided by grasslands emanate from the interactions between the roots of plant species and the soil in which they grow. We review current knowledge on the role of grassland ecosystems in delivering ecological and environmental benefits. We will consider how improved grassland can deliver these benefits, and the potential opportunities for plant breeding to improve specific traits that will enhance these benefits whilst maintaining forage production for livestock consumption. Opportunities for exploiting new plant breeding approaches, including high throughput phenotyping, and for introducing traits from closely related species are discussed.

The macro-invertebrate fauna and substrate were studied in a riffle and pool from a regulated (Elan) and an unregulated (Wye) river in summer. There were some differences in the substrate particle size distribution of the two rivers and between the riffle and the pool on the Wye. There was more detritus in pools than in riffles in both rivers and generally more in the Elan than the Wye. Deposits on the bed of the Elan were rich in iron and manganese.On the Wye. there was a greater density of invertebrates in the riffle than in the pool, but species richness was similar. Most species showed some preferences for either the riffle or the pool. The riffle contained a substantial number of Ephemeroptera, Trichoptera, Plecoptera and Simuliidae (529^) whilst the pool was dominated by chironomids {1\%). Compared with the Wye, total invertebrate density and species richness were reduced in the Elan. Some species characteristic of riffles were reduced or absent on the Elan. Invertebratedensityon the Elan was similar in the riffle and pool; species richness was greater in the riffle. The distribution and abundance of invertebrates is discussed in relation to such environmental factors as water velocity through the substrate and dissolved oxygen supply in interstitial habitats.

The soil ecosystem provides a habitat for numerous and diverse fauna which hold a pivotal role driving decomposition and nutrient cycling. However, changing land use or management can alter population dynamics, changing soil biology within the system. The implementation of different field management can improve soil fertility, whilst natural variations in plant species growth and root system may create changes to soil structure and properties. All plant species create a legacy effect within the soil to some extent; changing the environment either physically or through remaining plant residues. The impact of this legacy effect is difficult to perceive and only by monitoring will determine the change in soil faunal populations. An experiment investigated the hypothesis that previous forage cropping and establishment method would alter the diversity and abundance of soil fauna, during crop rotation. Four replicate plots of either perennial ryegrass (Lolium perenne), red clover (Trifolium pratense), white clover (Trifolium repens) or chicory (Cichorium intybus) (crop 1) were grown in a randomised block design (2009-2013), before becoming part of a crop rotation. These plots were split in spring 2013 and winter wheat (Triticum aestivum) established, either by ploughing or direct drilling; and harvested autumn 2013 (crop 2). Winter barley (Hordeum vulgare) was established using the same methodology in autumn 2013; and harvested autumn 2014 (crop 3). Soil fauna abundance after each crop rotation, including microfauna (nematodes), mesofauna (mites) and macrofauna (earthworms), showed legacy effects. Abundance of both earthworms and nematodes were affected by the original forage within crop 2; although after crop 3 the legacy effect began to diminish. Crop establishment method also affected abundance, although these were fauna dependent, with earthworm numbers being detrimentally affected by ploughing whilst nematode abundances increased with ploughing. Overall, the effect of perturbations and the consequences on biodiversity dynamics and function may have an important impact on crop sequence choices within agroecology.publishersversionPeer reviewe

Scullion, J. (2006). Remediating polluted soils. ?Naturwissenschaften, 93, (2), 51-65.This review focuses on treatment-based remediation of soils and the acquisition of data to support and monitor this remediation. Only in the last two decades has significant progress been made in regulating for soil pollution, with a parallel development of methodologies for soil assessment and remediation. However, soil complexity remains a problem for pollutant measurements relevant to environmental risk and informative to the design or evaluation of remediation technologies. Understanding the distribution of pollutants between different soil phases and the kinetics of transfer between these pools is fundamental to prediction for these processes; further progress is needed to characterise less accessible pollutant pools and to develop guidelines for their analysis. Available remediation options include physical, chemical and biological treatments, and these options offer potential technical solutions to most soil pollution. However, selecting the most appropriate approach requires detailed information on how pollutants interact with soil physio-chemical properties. Only general information is available as to the effectiveness of specific treatment systems for particular soil type?pollutant combinations. Given the high degree of heterogeneity in physio-chemical characteristics and pollutant distribution of affected soils, prediction of treatment timescales and levels of residual contamination remains a problem. On sites with a range of organic and inorganic pollutants present, combinations of different treatment approaches may offer the best prospect for effective remediation. Further work is needed to provide evidence that residual contamination does not pose significant risk and to evaluate effects of treatments on general soil function in relation to this contamination.Peer reviewe

Artificial discharges of water from reservoirs caused a six-fold and three-fold increase in discharge in the R . Tywi and R . Elan respectively but did not significantly alter particle size composition (by weight) and the porosity of the substratum or the organic matter content of fine particles (<0 .5 mm). Freshets in both rivers resulted in a consistent, though not significant, reduction in total densities of invertebrates and the densities of many major taxa and abundant species . During the freshet in the R . Elan, maximum concentration and total load of suspended solids were about 11 and 35 times greater than pre-release values respectively while invertebrate drift was dominated by Chironomidae (65%) and Plecoptera (25%) . Total numbers and densities of drifting chironomids increased immediately in response to the flow increase ; in contrast, numbers and densities of plecopterans increased later, during the night .