Farmland biodiversity and the footprint of agriculture

Sustainable development requires the reconciliation of demands for biodiversity conservation and increased agricultural production. Assessing the impact of novel farming practices on biodiversity and ecosystem services is fundamental to this process. Using farmland birds as a model system, we present a generic risk assessment framework that accurately predicts each species' current conservation status and population growth rate associated with past changes in agriculture. We demonstrate its value by assessing the potential impact on biodiversity of two controversial land uses, genetically modified herbicide-tolerant crops and agri-environment schemes. This framework can be used to guide policy and land management decisions and to assess progress toward sustainability targets.

Grassland leafhoppers (Hemiptera: Auchenorrhyncha) as indicators of habitat condition - a comparison of between-site and between-year differences in assemblage composition

The Auchenorrhyncha (leafhoppers) show great potential as indicators of grassland habitat quality, which would make them useful as a conservation tool. However, they are known to have labile populations. The relative importance of site identity and the year of sampling in the composition of leafhopper assemblages on chalk grassland are assessed for two sets of sites sampled twice. The study included a total of 95 sites (one set of 54, the other of 41), and demonstrated that for both sets the vegetation community and geographical location had high explanatory value, while the influence of year was small. The conclusion is that, notwithstanding population fluctuations, the leafhopper assemblages are a good indicator of habitat quality, and represent a potentially valuable tool in grassland conservation and restoration.

Linking bees and flowers: How do floral communities structure pollinator communities?

Pollinators provide essential ecosystem services, and declines in some pollinator communities around the world have been reported. Understanding the fundamental components defining these communities is essential if conservation and restoration are to be successful. We examined the structure of plant-pollinator communities in a dynamic Mediterranean landscape, comprising a mosaic of post-fire regenerating habitats, and which is a recognized global hotspot for bee diversity. Each community was characterized by a highly skewed species abundance distribution, with a few dominant and many rare bee species, and was consistent with a log series model indicating that a few environmental factors govern the community. Floral community composition, the quantity and quality of forage resources present, and the geographic locality organized bee communities at various levels: (1) The overall structure of the bee community (116 species), as revealed through ordination, was dependent upon nectar resource diversity (defined as the variety of nectar volume-concentration combinations available), the ratio of pollen to nectar energy, floral diversity, floral abundance, and post-fire age. (2) Bee diversity, measured as species richness, was closely linked to floral diversity (especially of annuals), nectar resource diversity, and post-fire age of the habitat. (3) The abundance of the most common species was primarily related to post-fire age, grazing intensity, and nesting substrate availability. Ordination models based on age-characteristic post-fire floral community structure explained 39-50% of overall variation observed in bee community structure. Cluster analysis showed that all the communities shared a high degree of similarity in their species composition (27-59%); however, the geographical location of sites also contributed a smaller but significant component to bee community structure. We conclude that floral resources act in specific and previously unexplored ways to modulate the diversity of the local geographic species pool, with specific disturbance factors, superimposed upon these patterns, mainly affecting the dominant species.

Introduction: perspectives for economically important wild species and neglected crops in the Mediterranean

The Mediterranean region is one of the major centres of origin and diversification of cultivated plants and many crop wild relatives are found there. In addition, many native species are still widely harvested from the wild for food, medicine and other uses and some of these have potential for development as alternative crop especially in marginal zones. While there have been several recent initiatives that address the cataloguing and conservation of these species, such as the Network on Identification, Conservation and Use of Wild Plants in the Mediterranean Region (MEDUSA and the Bioversity International (IPGRI) studies on Underutilized Mediterranean Species (VMS), no comprehensive assessment has yet been made and little work undertaken on their agricultural potential. It has been confidently predicted that consequences of global change in the Mediterranean region - population movements and migrations, changes in disturbance regimes, and climate change - will be serious. One the one hand, this will affect the survival prospects of many of these underutilized species and on the other hand it will enhance their importance as the source of potential new crop germplasm. The conservation and availability of genetic diversity of both crops and underutilized species is essential if we are to be able to meet the increasing demand for food and other crops that will be adapted to the new ecoclimatic envelopes that will develop in the region as a consequence of global change. The rapid rate of climatic and other change that is expected adds urgency to the task of assessing, conserving and sustainably using this rich diversity of wild species of economic value in the region but new strategies will be need to be developed to achieve this. The Mediterranean region has the potential of becoming a major source of new crop development in the coming decades.

Island ecosystems - priorities for conservation?

In terms of their land area, many islands contain a disproportionate number of taxa for certain groups of organisms. Thus the IUCN/WWF Centres of Plant Diversity project, which identifies 234 first order sites that are globally most important from a botanical point of view, includes a considerable proportion of islands, and in Conservation International’s Hotspot programme, Madagascar and the Indian Ocean Islands, the Philippines, and the Caribbean are identified as three of the five “hottest of the hotspots”. Priority for conservation action is often assumed for islands because of the often dramatic losses already suffered and the serious level of threats to which plant or animal populations are subjected, largely as a result of direct or indirect human action. The practicalities of conservation are not, however, straightforward in many cases. In the conservation of island hotspots of biodiversity, in addition to the many scientific and technical issues involved, political, financial and socio-economic factors also have to be addressed. The priorities for conservation will be examined in the light of targets set by the recently approved CBD Global Strategy for Plant Conservation and in the wider context of sustainable development of island ecosystems and the needs and aspirations of the people who inhabit them. Particular attention will be given to the threats from invasive species and the resultant increasing homogenization of floras and faunas, leading to the ‘deinsularization’ of islands.

Plant conservation: old problems, new perspectives

A review is given of the major conceptual changes that have taken place during the last 50 years in our understanding of the nature of plant conservation and of the principal methodological advances in undertaking conservation assessments and actions, largely through the incorporation of tools and techniques from other disciplines. The interrelationships between conservation and sustainable use are considered as well as the impact of the development of the discipline of conservation biology, the effects of the general acceptance of the concept of biodiversity and the practical implications of the implementation of the Convention on Biological diversity. The effect on conservation policy and management of the accelerating loss or conversion of habitats throughout the world and approaches for combating this are discussed.

Evaluation of agri-environmental and forestry schemes with multiple objectives

The evaluation of EU policy in the area of rural land use management often encounters problems of multiple and poorly articulated objectives. Agri-environmental policy has a range of aims, including natural resource protection, biodiversity conservation and the protection and enhancement of landscape quality. Forestry policy, in addition to production and environmental objectives, increasingly has social aims, including enhancement of human health and wellbeing, lifelong learning, and the cultural and amenity value of the landscape. Many of these aims are intangible, making them hard to define and quantify. This article describes two approaches for dealing with such situations, both of which rely on substantial participation by stakeholders. The first is the Agri-Environment Footprint Index, a form of multi-criteria participatory approach. The other, applied here to forestry, has been the development of ‘multi-purpose’ approaches to evaluation, which respond to the diverse needs of stakeholders through the use of mixed methods and a broad suite of indicators, selected through a participatory process. Each makes use of case studies and involves stakeholders in the evaluation process, thereby enhancing their commitment to the programmes and increasing their sustainability. Both also demonstrate more ‘holistic’ approaches to evaluation than the formal methods prescribed in the EU Common Monitoring and Evaluation Framework.

A framework for comparing pollinator performance: effectiveness and efficiency

Measuring pollinator performance has become increasingly important with emerging needs for risk assessment in conservation and sustainable agriculture that require multi-year and multi-site comparisons across studies. However, comparing pollinator performance across studies is difficult because of the diversity of concepts and disparate methods in use. Our review of the literature shows many unresolved ambiguities. Two different assessment concepts predominate: the first estimates stigmatic pollen deposition and the underlying pollinator behaviour parameters, while the second estimates the pollinator’s contribution to plant reproductive success, for example in terms of seed set. Both concepts include a number of parameters combined in diverse ways and named under a diversity of synonyms and homonyms. However, these concepts are overlapping because pollen deposition success is the most frequently used proxy for assessing the pollinator’s contribution to plant reproductive success. We analyse the diverse concepts and methods in the context of a new proposed conceptual framework with a modular approach based on pollen deposition, visit frequency, and contribution to seed set relative to the plant’s maximum female reproductive potential. A system of equations is proposed to optimize the balance between idealised theoretical concepts and practical operational methods. Our framework permits comparisons over a range of floral phenotypes, and spatial and temporal scales, because scaling up is based on the same fundamental unit of analysis, the single visit.

Assessing bee species richness in two Mediterranean communities: importance of habitat type and sampling techniques

The decline of bees has raised concerns regarding their conservation and the maintenance of ecosystem services they provide to bee-pollinated wild flowers and crops. Although the Mediterranean region is a hotspot for bee species richness, their status remains poorly studied. There is an urgent need for cost-effective, reliable, and unbiased sampling methods that give good bee species richness estimates. This study aims: (a) to assess bee species richness in two common Mediterranean habitat types: semi-natural scrub (phrygana) and managed olive groves; (b) to compare species richness in those systems to that of other biogeographic regions, and (c) to assess whether six different sampling methods (pan traps, variable and standardized transect walks, observation plots and trap nests), previously tested in other European biogeographic regions, are suitable in Mediterranean communities. Eight study sites, four per habitat type, were selected on the island of Lesvos, Greece. The species richness observed was high compared to other habitat types worldwide for which comparable data exist. Pan traps collected the highest proportion of the total bee species richness across all methods at the scale of a study site. Variable and standardized transect walks detected the highest total richness over all eight study sites. Trap nests and observation plots detected only a limited fraction of the bee species richness. To assess the total bee species richness in bee diversity hotspots, such as the studied habitats, we suggest a combination of transect walks conducted by trained bee collectors and pan trap sampling

Sediment fingerprinting as an environmental forensics tool explaining cyanobacteria blooms in lakes

Cyanobacteria (blue-green algae) blooms in water bodies present serious public health issues with attendant economic and ecological impacts. Llyn Tegid (Lake Bala) is an important conservation and amenity asset within Snowdonia National Park, Wales which since the mid-1990s has experienced multiple toxic cyanobacteria blooms threatening the ecology and tourism-dependent local economy. Multiple working hypotheses explain the emergence of this problem, including climate change, land management linked to increased nutrient flux, hydromorphological alterations or changing trophic structure - any of which may operate individually or cumulatively to impair lake function. This paper reports the findings of a sedimentfingerprinting study using dated lake cores to explore the linkages between catchment and lake management practices and the emergence of the algal blooms problem. Since 1900 AD lake bed sedimentation rates have varied from 0.06 to 1.07 g cm−2 yr−1, with a pronounced acceleration since the early 1980s. Geochemical analysis revealed increases in the concentrations of total phosphorus (TP), calcium and heavy metals such as zinc and lead consistent with eutrophication and a rising pollution burden, particularly since the late 1970s. An uncertainty-inclusive sedimentfingerprinting approach was used to apportion the relative fluxes from the major catchment land cover types of improved pasture, rough grazing, forestry and channel banks. This showed improved pasture and channel banks are the dominant diffuse sources of sediment in the catchment, though forestry sources were important historically. Conversion of rough grazing to improved grassland, coupled with intensified land management and year-round livestock grazing, is concluded to provide the principal source of rising TP levels. Lake Habitat Survey and particle size analysis of lake cores demonstrate the hydromorphological impact of the River Dee Regulation Scheme, which controls water level and periodically diverts flow into Llyn Tegid from the adjacent Afon Tryweryn catchment. This hydromorphological impact has also been most pronounced since the late 1970s. It is concluded that an integrated approach combining land management to reduce agricultural runoff allied to improved water level regulation enabling recovery of littoral macrophytes offers the greatest chance halting the on-going cyanobacteria issue in Llyn Tegid.

Institutional capacity and implementation issues in farmers' rights

Armed with the ‘equity’ and ‘conservation’ arguments that have a deep resonance with farming communities, developing countries are crafting a range of measures designed to protect farmers’ access to innovations, reward their contributions to the conservation and enhancement of plant genetic resources and provide incentives for sustained on-farm conservation. These measures range from the commericialization of farmers’ varieties to the conferment of a set of legally enforceable rights on farming communities – the exercise of which is expected to provide economic rewards to those responsible for on-farm conservation and innovation. The rights-based approach has been the cornerstone of legislative provision for implementing farmers’ rights in most developing countries. In drawing up these measures, developing countries do not appear to have systematically examined or provided for the substantial institutional capacity required for the effective implementation of farmers’ rights provisions. The lack of institutional capacity threatens to undermine any prospect of serious implementation of these provisions. More importantly, the expectation that significant incentives for on-farm conservation and innovation will flow from these ‘rights’ may be based on a flawed understanding of the economics of intellectual property rights. While farmers’ rights may provide only limited rewards for conservation, they may still have the effect of diluting the incentives for innovative institutional breeding programs – with the private sector increasingly relying on non-IPR instruments to profit from innovation. The focus on a rights-based approach may also draw attention away from alternative stewardship-based approaches to the realization of farmers’ rights objectives.

Identifying key knowledge needs for evidence-based conservation of wild insect pollinators: a collaborative cross-sectoral exercise

In response to evidence of insect pollinator declines, organisations in many sectors, including the food and farming industry, are investing in pollinator conservation. They are keen to ensure that their efforts use the best available science. We convened a group of 32 ‘conservation practitioners’ with an active interest in pollinators and 16 insect pollinator scientists. The conservation practitioners include representatives from UK industry (including retail), environmental non-government organisations and nature conservation agencies. We collaboratively developed a long list of 246 knowledge needs relating to conservation of wild insect pollinators in the UK. We refined and selected the most important knowledge needs, through a three-stage process of voting and scoring, including discussions of each need at a workshop. We present the top 35 knowledge needs as scored by conservation practitioners or scientists. We find general agreement in priorities identified by these two groups. The priority knowledge needs will structure ongoing work to make science accessible to practitioners, and help to guide future science policy and funding. Understanding the economic benefits of crop pollination, basic pollinator ecology and impacts of pesticides on wild pollinators emerge strongly as priorities, as well as a need to monitor floral resources in the landscape.