Loading...
4 results
Search Results
Now showing 1 - 4 of 4
- To what extent does the European common agricultural policy affect key landscape determinants of biodiversity?Publication . Pardo, Adara; Rolo, VĆctor; ConcepciĆ³n, Elena D.; DĆaz, Mario; Kazakova, Yanka; Stefanova, Vyara; Marsden, Katrina; Brandt, Katharina; Jay, Marion; Piskol, Stephan; Oppermann, Rainer; Schraml, Antonia; Moreno, GerardoAgricultural intensification continues to threaten habitat and biological diversity in farmland. In Europe, the Common Agricultural Policy (CAP) has established several measures to support biodiversity-fostering elements such as landscape features, semi-natural habitats and extensive land uses, together referred to as Green and Blue Infrastructure (GBI). However, CAP measuresā effectiveness to support GBI has not been accurately evaluated yet. We assess GBI occurrence across a variety of European agricultural systems covering a gradient of farming intensity and analyse to what extent the CAP is supporting their presence by enhancing farmer's awareness and the uptake of measures that foster GBI. We carried out habitat surveys in 115 Landscape Test Squares (LTS) of 500m Ć 500m in six case study areas, including arable land, pastures and mixed farming systems in Spain, Germany and Bulgaria. We mapped GBI including small landscape elements, in-field elements (both semi-natural and productive) and connectivity features. We used historical imagery to map changes on GBI occurrence in LTS from 2012 to 2018. We also used questionnaires with farmers and stakeholders on their GBI awareness and compared their answers to elements mapped. Results showed that landscape and in-field GBI occurrence was higher in extensive than in intensive farming systems regardless of the region, whereas the opposite was found for connectivity features (e.g. grassy strips). The analysis of habitat changes showed a small increase of certain biodiversity-fostering in-field GBI, but no substantial change in connectivity features or landscape elements. Moreover, a significant reduction of valuable GBI like grasslands was observed. There were several mismatches between the patterns of GBI identified by farmers and stakeholders and their mapped abundances. Our results indicate that the CAP has not substantially increased the availability of biodiversity-fostering GBI in these regions and that adopted features were mostly related to neutral or negative effects on biodiversity. Farmersā perception of GBI features seems driven by production management decisions rather than by biodiversity concerns.
- Worldwide importance of insect pollination in apple orchards : a reviewPublication . Pardo, Adara; Borges, Paulo A. V.Apple (Malus domestica) is one of the most important fruit crops globally. Apple trees depend greatly on insect pollination to achieve high yields and obtain fruits of acceptable marketable quality. Since insects, such as bees and hoverflies, are most important pollinators in apple orchards, a comprehensive understanding of their occurrence and activity is vital to ensure pollination services in this agroecosystem. Here, we review and synthesize the published research on the contribution of insects to apple pollination. In our review, we focused on the following five questions: i) Are there gaps in data availability across geographical regions and research topics? ii) What is the importance of insect pollination at determining yield and fruit quality in apple orchards? iii) What is the relative contribution of wild insects to apple pollination compared to honeybees? iv) What is the influence of landscape context (matrix) on regulating apple pollination? and v) How does agricultural management affect apple pollination?. Results showed that the information is limited for certain large apple producing countries, like China or Brazil. This finding stresses the need for further research in less studied regions. There were also gaps across research topics, highlighting the need for more experimental and empirical studies, particularly on the effect of local management practices on apple pollination. Substantial evidence from qualitative analyses supports the fact that insect pollination is essential for ensuring both yields and fruit quality in apple orchards across different regions. Besides, a significant proportion of studies showed that wild pollinators are abundant in apple orchards and they are frequently more effective pollinators than honeybees. Current available findings suggest a critical role of diverse semi-natural habitats surrounding apple orchards to sustain healthy pollinator communities, while the effect of local management was less consistent.
- Limited effect of management on apple pollination : a case study from an oceanic IslandPublication . Pardo, Adara; Lopes, David JoĆ£o Horta; Fierro, Natalia; Borges, Paulo A. V.Intensive agricultural practices leading to habitat degradation represent a major threat to pollinators. Diverse management practices are expected to influence wild pollinator abundance and richness on farms, although their effect in perennial crops is still unclear. In this study, we assessed the impact of management on apple (Malus domestica) pollination on an oceanic island, by comparing conventional (with and without herbicide application) and organic apple orchards. Pollinator visitation and pan trap surveys were carried out in six apple orchards in Terceira Island (Azores) and the landscape composition surrounding orchards was characterized. We also quantified fruit set, seed set and apple weight. We found no significant effect of management on insect visitation rates, whereas there was a negative association with increasing surrounding agricultural land. In contrast, management had an effect on species abundance, richness and diversity at the orchard level. Conventional orchards without herbicides showed higher abundance than the rest, but lower richness and diversity than conventional orchards with herbicides. Management had an effect on fruit set, but not on seed set or fruit weight. Our results suggest that management alone is insufficient for the overall improvement of apple pollination on an oceanic island, while landscape composition may play a relevant role.
- Management linked to ecological intensification supports insect pollinators in Iberian wood-pasturesPublication . Pardo, Adara; Rolo, Victor; Carrascosa, Alejandro; Gonzalez-Bornay, Guillermo; Moreno, GerardoABSTRACT: Context - Iberian wood-pastures (dehesas) constitute important habitats for flower-visiting insects, thus supporting the delivery of essential ecosystem services. However, dehesas have been experiencing increasing degradation either by farming intensification or abandonment. Objectives - We assess if alternative management strategies linked to ecological intensification, designed to maximize productivity in Iberian dehesas, are also favorable for biodiversity, specifically pollinators. Methods - We carried surveys in nine dehesas located across western and southwestern Spain. Each site comprised five paddocks under different management: conventional grazing, alternative systems linked to ecological intensification (rotational grazing, legume-enriched young and old pastures) and abandonment. We surveyed bees and hoverflies along fixed transects, together with flower cover and botanical composition, and we assessed landscape configuration. Results - Results showed that rotational grazing, legume-enriched and abandonment enhanced pollinator abundance compared to conventional management. Yet, ecological intensification practices were the most beneficial, showing a positive impact also on pollinator richness. Flower cover, together with plant diversity and landscape composition, were important drivers of pollinator diversity metrics. These patterns varied among pollinator groups, e.g., hoverflies were less impacted by management than bees, while being more affected by plant diversity. Conclusions - Our findings suggest that alternative management linked to ecological intensification has potential in low-input farming systems such as Iberian dehesas. These measures can help to maximize productivity, whilst preserving biodiversity and essential ecosystem services such as pollination. Complementary measures, such as the preservation or restoration of semi-natural habitats, also appear to be crucial for effectively safeguarding pollinating insects in this High Nature Value farming system.