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Selective logging is the most widespread habitat disturbance in tropical forests. Primary forest set‐asides along riparian zones are mandated in many countries and a key question is whether these riparian reserves provide biodiversity conservation benefits.We characterise butterfly communities in fixed‐width riparian reserves of 30 m on each bank along narrow streams (<10 m) paired with interior logged forest transects, and in primary forests within a selective logging concession in the south‐western Brazilian Amazon.We found that primary forest species richness was more similar to riparian reserves than to paired interior logged forest points, whereas abundance remained higher in both riparian reserves and interior logged points, likely due to the intrusion of canopy‐dwelling species in disturbed habitats, as previously reported in the literature. Butterfly assemblages within riparian reserves were more similar to unlogged primary forests than interior logged points, and canopy height in riparian reserves was associated with increased assemblage similarity to primary forest points.Changes in abundance relative to primary forest were of a larger magnitude in interior logged points than in riparian reserves within logged forests, highlighting the role of riparian reserves in maintaining primary forest‐like communities. We found no particular primary forest butterfly clades to be more sensitive to changes in abundance than other clades.Synthesis and applications. Mandatory conservation set‐asides around streams or rivers (riparian buffers) have an important role in protecting the abundance and composition of primary forest butterfly assemblages within selective logging concessions in tropical rainforests. This study highlights the need to assess the conservation value of protecting unlogged riparian forest strips in other taxa to inform policy. [ABSTRACT FROM AUTHOR]

There is a weak evidence base supporting the effective management of riparian ecosystems within tropical agriculture. Policies to protect riparian buffers—strips of non‐cultivated land alongside waterways—are vague and vary greatly between countries.From a rapid evidence appraisal, we find that riparian buffers are beneficial to hydrology, water quality, biodiversity and some ecosystem functions in tropical landscapes. However, effects on connectivity, carbon storage and emissions reduction remain understudied. Riparian functions are mediated by buffer width and habitat quality, but explicit threshold recommendations are rare.Policy implications. A one‐size fits all width criterion, commonly applied, will be insufficient to provide all riparian functions in all circumstances. Context‐specific guidelines for allocating, restoring and managing riparian buffers are necessary to minimise continued degradation of biodiversity and ecosystem functioning in tropical agriculture. A one‐size fits all width criterion, commonly applied, will be insufficient to provide all riparian functions in all circumstances. Context‐specific guidelines for allocating, restoring and managing riparian buffers are necessary to minimise continued degradation of biodiversity and ecosystem functioning in tropical agriculture. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents an analysis of the attitudes of farmers towards a policy approach that combines the instrument of set-aside of farmland with agri-environmental measures under the Common Agricultural Policy (CAP) for achieving nature goals. One of the stated objectives of current agricultural and environmental policies is to give greater consideration to issues of nature conservation in agricultural landscapes. To fulfil this objective, there is an urgent need to develop approaches that, on the one hand, are capable of delivering tangible improvements in the ecological situation and nature conservation in agriculture and, on the other hand, are structured in such a way that farmers are willing to put them into practice. In addition, such approaches need to be economical and affordable for society. The Leibniz-Centre for Agricultural Landscape Research (ZALF) has developed the concept of ‘nature-conservation set-aside’, especially for landscapes that are under predominantly arable use. Conservation set-aside refers to parts of arable farmland especially well suited to nature conservation, which are mandatorily withdrawn from agricultural production (for those who claim payment) and on which ecologically valuable habitats are created through specific management activities. To determine what kind of problems might arise for farmers in the course of implementing this concept as an agri-environmental measure, a survey was carried out in four largely arable regions of Germany. The results of this survey show the attitudes of German farmers regarding set-aside farmland for nature conservation in regions dominated by arable farming, and they demonstrate which factors influence the implementation of conservation set-aside. [Copyright &y& Elsevier]

Maintaining forest conservation set-asides is a key criterion of sustainability certification of many crops that drive tropical deforestation, but their value for carbon storage and associated biodiversity is unclear. We conducted vegetation measurements to examine the benefits of set-asides for aboveground carbon stocks (AGC) in certified oil palm plantations on Borneo, and whether their AGC is positively associated with plant diversity. The mean estimated AGC of live trees and palms ≥10 cm diameter in set-asides in certified oil palm plantations (52.8 Mg ha−1) was >1.5-times that of oil palm (30.3 Mg ha−1), with some plots supporting similar AGC to primary forest. For lowland Borneo, we estimate that the average AGC of oil palm plantations with 10% coverage of set-asides is up to 20% greater than the average AGC of oil palm plantations without set-asides, newly demonstrating carbon storage as a benefit of conservation set-asides. We found positive relationships between AGC and plant diversity, highlighting the carbon–biodiversity co-benefits of set-asides. However, set-asides had a lower density of tree seedlings than continuous primary forest, indicating potential suppression of future tree regeneration and AGC. Our findings support the application of zero-deforestation during agricultural development, to conserve areas of remaining forest with high AGC and high biodiversity. We recommend management practices that boost regeneration in existing set-asides (e.g. enrichment planting), which would be most effective in larger set-asides, and could substantially increase the AGC of agricultural landscapes without removing land from production, and help conserve forest-dependent biodiversity. • Conservation set-asides boost aboveground carbon stocks of oil palm plantations. • Set-asides co-benefit carbon and plant diversity compared to oil palm alone • Fewer seedlings in set-asides than primary forest may reduce tree regeneration. • Management of set-asides could improve their regeneration and plant diversity. [ABSTRACT FROM AUTHOR]