The Influence of Seed Mix and Management on the Performance and Persistence of Sown Forbs in Buffer Strips

A popular option under agri-environmental schemes throughout Europe has been the introduction of buffer strips adjacent to field boundaries. Buffer strips are usually established using grass-only seed mixes, or through natural regeneration. As a consequence, their function and biodiversity value might be limited due to a low presence of desirable forb species. Given the financial barrier of using forb-rich seed mixes, there is a need to identify species that establish reliably in parallel with management options that encourage their persistence. In a 5-year study across three different sites we investigated the responses of 32 different forb species sown in two different grass-based seed mixes tailored to soil type. Generally, there was an increase in sown forb cover with time, and this effect was greatest in plots sown with fine-grasses treated with an application of graminicide or an annual cut. We have identified a suite of ten forb species that are likely to establish and persist in buffer strip habitats

Wildflower Strip Establishment for the Delivery of Ecosystem Services in Sweet Cherry Orchards

The practice of introducing wildflower habitats in cropped areas is an approach that can be used to enhance ecosystem services. The value of such an approach will be affected by the establishment success of the sown species. To investigate this, 12 strips of wildflower habitat were established in alleyways between rows of cherry trees at three sites in the West Midlands (UK). The establishment of plants in sown strips was compared to six untreated alleyways that received conventional management. Eight forb species and one grass species was sown in strips measuring 1 m × 95 m. The establishment success of the sown species and their contribution to the vegetation of the alleyway was determined using percentage cover assessments in replicate quadrats. Dactylis glomerata, Leucanthemum vulgare, Prunella vulgaris and Lotus corniculatus established most consistently and with greater cover values in the sown strips. However, the sown strips were also associated with a greater abundance of unsown species, some of which are classed as weeds

Developing perennial wildflower strips for use in Mediterranean orchard systems

To support sustainable food production and the delivery of ecosystem services through ecological intensification, wildflower strips have become a popular strategy. Despite their success in temperate orchard systems, they remain understudied in Mediterranean ecosystems, which poses a significant barrier to uptake. In order to further promote their adoption, seed mixes must be optimised for commercial orchard systems and for the Mediterranean climate. Plant species should be selected for their consistent performance, whilst the availability of resources for ecosystem service providers determines the quality of the wildflower strip. In this study, the suitability of 12 native perennial forbs and two tussock-forming grass species for wildflower strips in commercial Citrus orchards was assessed over a 3-year period. Distinct resources for natural enemies according to the different plant growth stages were used an indicator of wildflower strip quality. The wildflower strips were managed under two different cutting strategies: (i) standard management, in which wildflower strips were cut once annually in February, and (ii) active management, in which wildflower strips were cut two additional times each year. The establishment and success of the sown species were compared. The influence of wildflower strips and their management on plant species richness, community structure, and the provision of resources was com -pared with a control treatment, in which alleyways were managed conventionally by cutting any naturally occurring vegetation to a height of ≤5 cm, four to five times annual. For the first time, the performance of native perennial plant species has been assessed in Mediterranean orchard systems and a seed mix developed for targeting pest regulation services. The wildflower strips were successful in increasing plant species richness and the available resources expected to support natural enemies. However, only wildflower strips managed with cutting once annually enhanced vegetation cover relative to the control, whilst extending the flowering period. This study therefore provides crucial tools for the further development of sustainable approaches to food production in Mediterranean orchard systems

Predicting Potential Distribution of Orchis Galilaea in Lebanon Using GIS

Orchis galilaea is the only Lebanese orchid that is restricted geographically to Lebanon, Palestine and Jordan. It is a terrestrial orchid that attracts its pollinator by sexual deception while offering no reward. The full distribution of this orchid in Lebanon has not been determined. This study is part of ongoing research into the population dynamics of the orchid to form a management plan for its conservation. A Geographic Information System (GIS) was used to identify the habitat characteristics of O. galilaea and map its distribution in Lebanon by combining known locations with digital layers of environmental variables, including topography, land cover, soil type, geology and precipitation. Classes within each environmental parameter were defined and weighted according to their frequency of occurrence at extant sites. A predictive GIS model was developed by overlaying the five layers of the habitat characteristics. The predicted distribution map of O. galilaea was then validated by confirming presence of the orchid in the predicted locations and absence in the unsuitable areas through exploration field trips. Eighty five locations were surveyed and seven previously unknown populations of O. galilaea were discovered. These new O. galilaea locations were all correctly predicted by the model as potential habitat. The accuracy of the model was confirmed as it was significantly more likely to find the orchid in predicted suitable habitat compared with unsuitable habitat. Combining ecological habitat characteristics using GIS proved to be a useful tool to successfully predict the potential distribution of O. galilaea in Lebanon and will assist in planning its conservation measures

The potential of wildflower strips to enhance pollination services in sweet cherry orchards grown under polytunnels

Sweet cherry production benefits from insect pollination, but the extent to which wildflower strips can boost pollinator visitation under polytunnels is unknown. Wildflowers were established in alleyways between tree rows under polytunnels in 10 commercial cherry orchards. Their management involved either a single cut in September (Standard Wildflower Strips (SWS)) or being actively maintained to 20 cm with regular cutting (Actively Managed Wildflower Strips (AMWS)), compared with unsown Control Strips (CS). Flower visitors of cherry and wildflowers were recorded by visual observations for 3 years (2017–2019), while cherry production (quantity and quality) was assessed in 2019. In total, 67 visitor species were identified; managed commercial species (Apis mellifera and Bombus terrestris) made up ~74% of all records. During the cherry blossom period (anthesis), AMWS had the highest visitor density to cherry blossoms compared with CS and SWS but no significant difference in harvestable fruit was recorded. After anthesis, greater visitor density, diversity and richness were observed in both wildflower treatments compared with CS, being greatest in SWS, which was consistent with differences in floral communities between treatments. Although visitor density was not correlated with fruit set, pollinating insects were key for fruit yields and quality. Fruit set was ~17% from blossoms exposed to visitors compared with <1% when excluded. Furthermore, hand pollination resulted in ~32% fruit set, indicating greatest pollination deficits in CS (~50%) compared with AMWS (~28%) and SWS (~35%). Synthesis and applications. Sweet cherry is highly dependent on pollinators to underpin commercial yields, and pollination deficits exist under polytunnels. Growers should, therefore, reconsider their pollination strategies and look to combine effective pollinator management with polytunnel use to mitigate deficits; establishing and actively managing wildflowers in alleyways could enhance wild visitors and pollination

The potential for wildflower interventions to enhance natural enemies and pollinators in commercial apple orchards is limited by other management practices

Modern fruit production has successfully increased yields and fruit quality to meet market demands mainly through intensification and the use of Plant Protection Products (PPPs). Due to the associated environmental impacts and consumers increasingly demanding food produced more sustainably, the tree fruit sector is seeking to reduce its reliance on PPPs. Despite intensification, apple production is still highly dependent on ecosystem services, including pest regulation and pollination. The aim of this study was to investigate the response of natural enemies and pollinators in commercial apple orchards to the provision of a wildflower habitat. It was hypothesised that the abundance and diversity of beneficial invertebrate species would be enhanced leading to an increased control of apple pests and enhanced pollination of apple blossom. We also investigated the effect of orchard pesticide toxicity on natural enemies and pest regulation services and how responses varied between apple cultivars (Jazz and Braeburn). The study was carried out in five orchards of each apple variety across Kent (UK), using a split-plot experimental design. At each site, a one-hectare orchard plot was established with wildflower strips in alleyways between rows of trees and compared with a one-hectare control plot where alleyways were managed conventionally with regular cutting. Responses of natural enemies and pollinators were recorded over a period of three and four years, respectively. The presence of wildflower strips did not contribute significantly towards the delivery of natural pest regulation or pollination services. However, hoverfly diversity and species richness were greater in orchards with wildflower strips, and whilst this was not associated with increased rates of pest regulation, such a response could potentially provide more resilient pest regulation and pollination services. Braeburn orchards had higher bee abundance, and pest predation rates, which were associated with a greater abundance of earwigs, compared to Jazz orchards. Of key significance for growers is that high values of cumulative pesticide toxicity negatively affected natural enemy populations, especially earwigs. If growers want to support natural enemies and wild pollinators in modern apple orchards following the principles of ecological intensification, they need to consider both the types and frequency of pesticide sprays used, in conjunction with interventions aimed at promoting beneficial invertebrates

Biological Flora of Britain and Ireland: <i>Geranium pratense</i> - No. 305

1. This account presents information on all aspects of the biology of Geranium pratense L. (Meadow Crane's‐Bill). The main topics are presented within the standard framework of the Biological Flora of Britain and Ireland : distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characters, herbivores and disease, history and conservation.2. Geranium pratense is a perennial gynodioecious forb of neutral grassland. In Britain and Ireland, it is particularly abundant on roadside verges, railway embankments, the margins of watercourses and woodland rides. It is generally intolerant of grazing and is absent or scarce in livestock‐grazed grassland. Geranium pratense is widespread in England, Wales and Scotland but is scarce in Ireland. It has an extensive native range in Europe and Asia, extending eastwards to Russia, north‐western China and Mongolia. It has been widely introduced to new sites within its native range and has been introduced to Canada, the USA and New Zealand. 3. Geranium pratense usually occurs on free‐draining soils but also infrequently where drainage is impeded. The soils are often nutrient‐rich and weakly acidic to weakly alkaline. The underlying geology is usually non‐acidic sedimentary rocks or superficial deposits. 4. Geranium pratense is protandrous and is pollinated by various insects of the orders Hymenoptera, Diptera and Lepidoptera, particularly bumblebees, solitary bees, hoverflies and butterflies. Eleven species of phytophagous insect have been recorded on G. pratense in Britain and Ireland.5. Geranium pratense has little or no capacity for vegetative spread. Primary seed dispersal is ballistic and seeds may be flung over distances of up to several metres. The species has a transient seed bank, that is germination typically takes place in the winter and spring after seed production, after the physically dormant seeds have become permeable. Seedling establishment is higher in vegetation‐free gaps than in undisturbed grassland vegetation.6. There has been no significant change in its distribution between the late 1950s and 2019, although since 2000, it has expanded its range, mainly via introductions, in northern and western Scotland, west Wales and in Ireland. Alien sites have increased markedly since the 1960s due to introductions from wildflower seed sowing and spread from gardens

Ecological Interactions of the Sexually Deceptive Orchid Orchis Galilaea

Plant species dependent on highly specific interactions with pollinators are vulnerable to environmental change. Conservation strategies therefore require a detailed understanding of pollination ecology. This two-year study examined the interactions between the sexually deceptive orchid, Orchis galilaea, and its pollinator Lasioglossum marginatum. Relationships were investigated across three different habitats known to support O. galilaea (garrigue, oak woodland, and mixed oak/pine woodland) in Lebanon. Visitation rates to flowers were extremely low and restricted to male bees. The reproductive success of O. galilaea under ambient conditions was 29.3% (±2.4), compared to 89.0% (±2.1) in plants receiving cross-pollination by hand. No difference in reproductive success was found between habitat types, but values of reproductive success were positively correlated to the abundance of male bees. Pollination limitation can have negative impacts on the population growth of orchids, and this study provides clear evidence for more holistic approaches to habitat conservation to support specific interactions

Reliably predicting pollinator abundance: challenges of calibrating process-based ecological models

1. Pollination is a key ecosystem service for global agriculture but evidence of pollinator population declines is growing. Reliable spatial modelling of pollinator abundance is essential if we are to identify areas at risk of pollination service deficit and effectively target resources to support pollinator populations. Many models exist which predict pollinator abundance but few have been calibrated against observational data from multiple habitats to ensure their predictions are accurate. 2. We selected the most advanced process-based pollinator abundance model available and calibrated it for bumblebees and solitary bees using survey data collected at 239 sites across Great Britain. We compared three versions of the model: one parameterised using estimates based on expert opinion, one where the parameters are calibrated using a purely data-driven approach and one where we allow the expert opinion estimates to inform the calibration process. 3. All three model versions showed significant agreement with the survey data, demonstrating this model's potential to reliably map pollinator abundance. However, there were significant differences between the nesting/floral attractiveness scores obtained by the two calibration methods and from the original expert opinion scores. 4. Our results highlight a key universal challenge of calibrating spatially-explicit, process-based ecological models. Notably, the desire to reliably represent complex ecological processes in finely mapped landscapes necessarily generates a large number of parameters, which are challenging to calibrate with ecological and geographical data that is often noisy, biased, asynchronous and sometimes inaccurate. Purely data-driven calibration can therefore result in unrealistic parameter values, despite appearing to improve model-data agreement over initial expert opinion estimates. We therefore advocate a combined approach where data-driven calibration and expert opinion are integrated into an iterative Delphi-like process, which simultaneously combines model calibration and credibility assessment. This may provide the best opportunity to obtain realistic parameter estimates and reliable model predictions for ecological systems with expert knowledge gaps and patchy ecological data

Neural Systems for Reading Aloud: A Multiparametric Approach

Reading aloud involves computing the sound of a word from its visual form. This may be accomplished 1) by direct associations between spellings and phonology and 2) by computation from orthography to meaning to phonology. These components have been studied in behavioral experiments examining lexical properties such as word frequency; length in letters or phonemes; spelling–sound consistency; semantic factors such as imageability, measures of orthographic, or phonological complexity; and others. Effects of these lexical properties on specific neural systems, however, are poorly understood, partially because high intercorrelations among lexical factors make it difficult to determine if they have independent effects. We addressed this problem by decorrelating several important lexical properties through careful stimulus selection. Functional magnetic resonance imaging data revealed distributed neural systems for mapping orthography directly to phonology, involving left supramarginal, posterior middle temporal, and fusiform gyri. Distinct from these were areas reflecting semantic processing, including left middle temporal gyrus/inferior-temporal sulcus, bilateral angular gyrus, and precuneus/posterior cingulate. Left inferior frontal regions generally showed increased activation with greater task load, suggesting a more general role in attention, working memory, and executive processes. These data offer the first clear evidence, in a single study, for the separate neural correlates of orthography–phonology mapping and semantic access during reading aloud