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Abstract Agricultural expansion and intensification threaten pollinator populations worldwide, potentially jeopardizing crop pollination. Although the highest rates of cropland expansion are currently found within the tropics, quantifying effects of landscape composition on tropical pollinator communities and the provided pollination services to crops has received relatively limited attention. Here, we studied the relationship between land use in the landscape matrix surrounding Ethiopian coffee production forests and their bee communities and coffee pollination services. We used pan traps to collect bees from 20 plots located in small-scale coffee (Coffea arabica) production forests of varying size in a major Arabica coffee production zone in southwestern Ethiopia. To estimate the provided coffee pollination services, we performed pollinator exclusion experiments and calculated yield stability across three years. We collected 595 bees belonging to 27 species, with the honeybee (Apis mellifera) as dominant species. We found a significant convex parabolic relationship between the non-Apis bee diversity within coffee production forests and the proportion of open agricultural land in the surrounding landscape. Pollinator exclusion resulted in a significantly lower initial, but not final, fruit set. Whereas initial fruit set was not affected by the composition of the bee community, our results indicated a positive relation between non-Apis bee diversity and temporal coffee yield stability. High proportions of fruit drop suggested that physiological stress factors may have abrogated the potential benefits of insect pollination in the final fruit set. We conclude that the agricultural land and homesteads surrounding the coffee production forests still support sufficient nesting and feeding resources for non-Apis bees, hence providing a source of potential coffee pollinators. Increasing human population in the region and the increasing demand for food may present future challenges to reconcile the required increased agricultural production with the conservation of pollinator species and pollination services.

Abstract Declines of pollinator diversity are causing concern about pollination service security for agriculture and natural ecosystems. Landscape composition has been found to regulate the diversity of pollinator communities and their corresponding pollination services in agricultural fields, with previous research concluding positive effects of semi-natural habitat or negative effects of intensive agriculture. In our study we assessed pollinator diversity and pollination services in sweet cherry orchards (Prunus avium) along two non-collinear, independent gradients of semi-natural habitat and intensive agriculture (i.e. percentage of cultivated land) around the orchards. The influence of floral resources in the herb layer in the orchards was also assessed. Our results show that semi-natural habitat clearly support pollinator species richness and wild pollinator abundance. Next to semi-natural habitat, flowering plants in the herb layer of the orchards was an additional driver of pollinator diversity in sweet cherry orchards. Although approximately 80% of all flower visitors were managed honey bees, fruit set of sweet cherry was only clearly linked to pollinator species richness and wild pollinator abundance. Management strategies to support sweet cherry production might include the creation of semi-natural habitat around orchards and the promotion of floral resources in the orchard’s herb layer to support pollinating insects.

International audience; Supporting functional biodiversity (FB), which provides natural pest regulation, is an environmentally sound and promising approach to reduce pesticide use in perennial cultures such as apple, especially in organic farming. However, little is known about farmers' practices and motivations to implement techniques that favor FB, especially whether or not they really expect anything from FB in terms of pest regulation. In fact, FB-supporting techniques (FB-techniques) are massively questioned by practitioners due to inadequate information about their effectiveness. An interview survey was performed in eight European countries(i) to describe farmers' practices and identify promising FB-techniques: (ii) to better understand their perceptions of and values associated with FB; and (iii) to identify potential drivers of (non-) adoption. Fifty-five advisors and 125 orchard managers with various degrees of experience and convictions about FB were interviewed and a total of 24 different FB-techniques which can be assigned to three different categories (ecological infrastructures, farming practices and redesign techniques) were described. Some were well-established measures (e.g., hedges and bird houses), while others were more marginal and more recent (e.g., animal introduction and compost). On average, farmers combined more than four techniques that had been implemented over a period of 13 years, especially during their establishment or conversion period. In general, it was difficult for farmers to evaluate the effectiveness of individual FB-techniques on pest regulation. They considered FB-techniques as a whole, targeting multiple species, and valued multiple ecosystem services in addition to pest regulation. The techniques implemented and their associated values differed among farmers who adopted various approaches towards FB. Three different approaches were defined: passive, active and integrated. Their appraisal of FB is even more complex because it may change with time and experience. These findings provide empirical evidence that the practical implementation of promising techniques remains a challenge, considering the diversity of situations and evaluation criteria. Increased cooperation between researchers, farmers and advisors should more effectively target research, advisory support and communication to meet farmers' needs and perceptions.

The conversion of natural habitats to agriculture is one of the main drivers of biotic change. Madagascar is no exception and land-use change, mostly driven by slash-and-burn agriculture, is impacting the island's exceptional biodiversity. Although most species are negatively affected by agricultural expansion, some, such as synanthropic bats, are capable of exploring newly available resources and benefit from man-made agricultural ecosystems. As bats are known predators of agricultural pests it seems possible that Malagasy bats may be preferentially foraging within agricultural areas and therefore provide important pest suppression services. To investigate the potential role of bats as pest suppressors, we conducted acoustic surveys of insectivorous bats in and around Ranomafana National Park, Madagascar, during November and December 2015. We surveyed five landcover types: irrigated rice, hillside rice, secondary vegetation, forest fragment and continuous forest. 9569 bat passes from a regional assemblage of 19 species were recorded. In parallel, we collected faeces from the six most common bat species to detect insect pest species in their diet using DNA metabarcoding. Total bat activity was higher over rice fields when compared to forest and bats belonging to the open space and edge space sonotypes were the most benefited by the conversion of forest to hillside and irrigated rice. Two economically important rice pests were detected in the faecal samples collected - the paddy swarming armyworm Spodoptera mauritia was detected in Mops leucogaster samples while the grass webworm Herpetogramma licarsisalis was detected from Mormopterus jugularis and Miniopterus majori samples. Other crops pests detected included the sugarcane cicada Yanga guttulata, the macadamia nut-borer Thaumatotibia batrachopa and the sober tabby Ericeia inangulata (a pest of citrus fruits). Samples from all bat species also contained reads from important insect disease vectors. In light of our results we argue that Malagasy insectivorous bats have the potential to suppress agricultural pests. It is important to retain and maximise Malagasy bat populations as they may contribute to higher agricultural yields and promote sustainable livelihoods. Accepted manuscript version, licensed CC BY-NC-ND 4.0.

In this paper we present effects of four paired agricultural management practices (organic matter (OM) addition versus no organic matter input, no-tillage (NT) versus conventional tillage, crop rotation versus monoculture, and organic agriculture versus conventional agriculture) on five key soil quality indicators, i.e., soil organic matter (SOM) content, pH, aggregate stability, earthworms (numbers) and crop yield. We have considered organic matter addition, no-tillage, crop rotation and organic agriculture as “promising practices”; no organic matter input, conventional tillage, monoculture and conventional farming were taken as the respective references or “standard practice” (baseline). Relative effects were analysed through indicator response ratio (RR) under each paired practice. For this we considered data of 30 long-term experiments collected from 13 case study sites in Europe and China as collated in the framework of the EU-China funded iSQAPER project. These were complemented with data from 42 long-term experiments across China and 402 observations of long-term trials published in the literature. Out of these, we only considered experiments covering at least five years. The results show that OM addition favourably affected all the indicators under consideration. The most favourable effect was reported on earthworm numbers, followed by yield, SOM content and soil aggregate stability. For pH, effects depended on soil type; OM input favourably affected the pH of acidic soils, whereas no clear trend was observed under NT. NT generally led to increased aggregate stability and greater SOM content in upper soil horizons. However, the magnitude of the relative effects varied, e.g. with soil texture. No-tillage practices enhanced earthworm populations, but not where herbicides or pesticides were applied to combat weeds and pests. Overall, in this review, yield slightly decreased under NT. Crop rotation had a positive effect on SOM content and yield; rotation with ley very positively influenced earthworms’ numbers. Overall, crop rotation had little impact on soil pH and aggregate stability − depending on the type of intercrop; alternatively, rotation of arable crops only resulted in adverse effects. A clear positive trend was observed for earthworm abundance under organic agriculture. Further, organic agriculture generally resulted in increased aggregate stability and greater SOM content. Overall, no clear trend was found for pH; a decrease in yield was observed under organic agriculture in this review.

Reduction of soil tillage is of paramount importance for agricultural soil preservation. However, it is often accompanied by yield reduction and weed management problems. In this perspective, cover crops could play an important role to alleviate weed infestation and sustain yield. In this study, the results from a three-year experiment of cover crop cultivation in different soil tillage treatments is presented, together with results from DayCent simulations on the long term evolution of soil organic carbon and total nitrogen. Eight cover crop treatments were set up as subtreatments in a long term experiment in Switzerland. Cover crops were cultivated for a short two-month period between two winter wheats. Substantial differences in cover crop growth were observed depending on cover crop species. In all tillage treatments, high cover crop biomass production allowed to supress weed biomass compared to the no cover crop control. Wheat grain yield was higher in the minimum tillage than in the plough treatment. In the no till treatment, wheat yield was notably low, except in the field pea treatments, where wheat yield reached values similar to that observed in the plough and minimum tillage treatments. In addition, these differences in biomass production translated into important differences in nutrient inputs, and even in soil nutrient concentration in some cases. Long term simulations showed that cover crop cultivation could increase drastically soil organic carbon and total nitrogen, especially in reduced tillage treatments. Altogether, these results demonstrated that the presence of a well-developed cover crop, even for only two months, allows to sustain wheat yield in a no till treatment. It impacts also soil fertility and nutrient cycling. This study shows that an accurate use and management of cover crops, in interaction with tillage reduction, could maintain yield and improve soil fertility in the long term. Agriculture, Ecosystems & Environment, 256 ISSN:0167-8809 ISSN:1873-2305

Abstract Low mineral fertiliser use received much attention in Africa over the last decades. As fertiliser sales have exponentially grown in Ethiopia, and evidence exists of a supply that is beyond the demand in the drier northern parts of the country, we investigated the geographical determinants of inorganic fertiliser sales and its resale prices in north Ethiopia. Quantitative data on fertiliser provision and prices on the black market in 2016 were obtained from official statistics and from key informants in each of the 35 studied districts and in all municipalities of the Raya area. Environmental variables were collected from spatial databases. To promote inorganic fertiliser, agricultural experts use incentives, and also barter the purchase of fertiliser by a farmer against food aid or other advantages from the authorities. The high application rate that is aimed at (200 kg ha−1) contrasts with the dominance of less-responsive soils in the study area, for which inorganic fertiliser application does not result in higher crop yields, or even leads to root burn. The quantitative analysis shows that 40.7 103 Mg of fertiliser were officially sold in the study area in 2016, which corresponds to 52 kg ha−1. This is notably different from the application rate, as reselling widely occurs, at 50% of the official price for diammonium phosphate (DAP) and 54% for urea, mostly to users outside the community. By accepting the opportunity offered by agricultural companies and traders, smallholders save themselves from greater losses. The black market rate is strongly and positively correlated to monthly rainfall at sowing time (July 2016) (R2 = 0.44; n = 31; p

Intensification of agriculture, combined with poor agronomic practices have increased the incidence of plant parasitic nematodes (PPN) and other soil pathogens in East Africa, which consequently affects crop productivity in small holder farms. The objective of the study was to assess the effectiveness of farming systems in management of PPN and to recommend the best practice to farmers. Therefore, two field trials were established, one infarmer fieldsandoneon-station,usingmaize (Zeamays L.), intercroppedwithbeans(Phaseolusvulgaris L.) and in rotationwith beans as asole crop. Organic farming(that receivedcompost, Tithonia diversifolia and neem cake (Azadirachta indica)) was compared to conventional farming (that received fertilizer and nematicide), farmer practice (that received manure, Tithonia diversifolia and wood ash), and a farm with no input application (control). After threeyearsof continuouscultivation, twelve generaofPPNwere recovered fromsoiland/or root samples from the trials. Under inter- and sole-cropping at both sites, the abundance of PPN including Pratylenchus and Meloidogyne were significantly reduced in the organic system compared to the conventional, farmer practices and control. Organic farming was effective in reducing the genera of PPN below the control for a longer period (4 months) compared to conventional farming and farmer practice (2 months). The findings demonstrated the potential of organic farming in the suppression of PPN at the farmer level. Policy development and extension services can therefore consider organic farming as an alternative method in managing soil-borne nematodes in small holder farms in sub-Saharan Africa. However, further studies are required on other crops, in dry areas and the period to top-dress with organic amendments to assure effective suppression of PPN in organic farming.