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Varied strategies to alleviate the loss of farmland biodiversity have been tested, yet there is still insufficient evidence supporting their effectiveness, especially when considering phylogenetic and functional diversity alongside traditional taxonomic diversity metrics. This conservation challenge is accentuated in the Afrotropics by the rapid agricultural expansion and intensification for the production of cash crops and by a comparative lack of research. In this study, we assessed how farming practices influence avian phylogenetic and functional diversity. We conducted point‐count surveys to assess avian diversity in monocultures of tea and mixed crop farming systems surrounding the Nyungwe rainforest in south‐west Rwanda, allowing us to investigate the drivers of avian diversity at farm level. Species composition was found to be moderately different between farm types, with mixed crop farms supporting higher phylogenetic diversity than tea plantations. There were no significant seasonal differences in species composition, functional or phylogenetic diversity. Overall, functional diversity did not differ between farm types, but the dispersion of trophic‐related traits was significantly higher in mixed crop farms. Both functional and phylogenetic diversity were influenced by floristic diversity, vegetation height, tree number, and elevation to varying degrees. Our results also (i) highlight the role of farmland heterogeneity (e.g., crop species composition, height, and tree cover extent) in encouraging avian functional and phylogenetic diversity in the Afrotropics and (ii) indicate that the generally negative biodiversity impacts of monoculture agriculture can be partially alleviated by extensive agroforestry with an emphasis on indigenous tree species. [ABSTRACT FROM AUTHOR]

Abstract Varied strategies to alleviate the loss of farmland biodiversity have been tested, yet there is still insufficient evidence supporting their effectiveness, especially when considering phylogenetic and functional diversity alongside traditional taxonomic diversity metrics. This conservation challenge is accentuated in the Afrotropics by the rapid agricultural expansion and intensification for the production of cash crops and by a comparative lack of research. In this study, we assessed how farming practices influence avian phylogenetic and functional diversity. We conducted point‐count surveys to assess avian diversity in monocultures of tea and mixed crop farming systems surrounding the Nyungwe rainforest in south‐west Rwanda, allowing us to investigate the drivers of avian diversity at farm level. Species composition was found to be moderately different between farm types, with mixed crop farms supporting higher phylogenetic diversity than tea plantations. There were no significant seasonal differences in species composition, functional or phylogenetic diversity. Overall, functional diversity did not differ between farm types, but the dispersion of trophic‐related traits was significantly higher in mixed crop farms. Both functional and phylogenetic diversity were influenced by floristic diversity, vegetation height, tree number, and elevation to varying degrees. Our results also (i) highlight the role of farmland heterogeneity (e.g., crop species composition, height, and tree cover extent) in encouraging avian functional and phylogenetic diversity in the Afrotropics and (ii) indicate that the generally negative biodiversity impacts of monoculture agriculture can be partially alleviated by extensive agroforestry with an emphasis on indigenous tree species.

Context: Biodiversity is closely related to landscape heterogeneity, but both are difficult to evaluate directly. Apex predators, such as raptors, are potential surrogate indicators of diversity, but previous studies using a correlative approach have been heavily criticised. Objectives: We evaluated whether space use by a generalist avian predator, the lesser spotted eagle Clanga pomarina, is an effective indicator of functional landscape heterogeneity and evaluate mechanisms driving this relationship. Methods: We used GPS-tracking of eagles over eight breeding seasons along with precise field mapping data for broad and detailed land-use types from Estonia, Eastern Europe. We analysed the effects of various landscape metrics and composition on movement patterns of eagles. Results: Activity centres of eagles were associated with configurational heterogeneity, as evidenced by their foraging on the edges of small complex patches more often than expected at random. The eagles also avoided roads (disturbance) and preferred forest edges (ecotones with abundant prey and perch sites). The importance of compositional heterogeneity was revealed by preferences for specific land-use types (e.g. spring-sown but not autumn-sown wheat); preferred crops changed over time. The model including only general land-use classes was outperformed by the model based on a detailed classification. Conclusions: Movement ecology provides an opportunity to biomonitor the heterogeneity of landscapes and adds a functional perspective to earlier raptor-biodiversity correlation studies. This suggests that in addition to GPS-tracking, large quantities of opportunistic observations by citizen scientists can be used to evaluate biodiversity across landscapes. [ABSTRACT FROM AUTHOR]

Mapping and assessment of ecosystem services in agricultural landscapes as required by the EU biodiversity policy need a better characterization of the given landscape typology according to its ecological and cultural values. Such need should be accommodated by a better discrimination of the landscape characteristics linked to the capacity of providing ecosystem services and socio-cultural benefits. Often, these key variables depend on the degree of farmland heterogeneity and landscape patterns. We employed segmentation and landscape metrics (edge density and image texture respectively), derived from a pan-European multi-temporal and multi-spectral remote sensing dataset, to generate a consistent European indicator of farmland heterogeneity, the Farmland Heterogeneity Indicator (FHI). We mapped five degrees of FHI on a wall-to-wall basis (250 m spatial resolution) over European agricultural landscapes including natural grasslands. Image texture led to a clear improvement of the indicator compared to the pure application of Edge Density, in particular to a better detection of small patches. In addition to deriving a qualitative indicator we attributed an approximate patch size to each class, allowing an indicative assessment of European field sizes. Based on CORINE land cover, we identified pastures and heterogeneous land cover classes as classes with the highest degree of FHI, while agroforestry and olive groves appeared less heterogeneous on average. We performed a verification based on a continental and regional scale, which resulted in general good agreement with independently derived data. [ABSTRACT FROM AUTHOR]

Milkweed has declined substantially, with over 80% declines in some agricultural regions. This threatens monarch butterfly (Danaus plexippus) persistence, because monarch larvae feed solely on milkweed. Thus conservation actions are needed to enhance the availability of milkweed, particularly in agricultural landscapes. Conservation actions to date have largely focused on reducing intensive agricultural practices, mainly use of herbicides. However, research suggests that landscape-scale alteration of the cropped portion of an agricultural landscape (the "farmland"), for example, to reduce crop field sizes, can benefit herbaceous plants such as milkweed. Here we collected data on milkweed occurrence and cover in agricultural landscapes in Ontario, Canada, capturing variability in milkweed from field edge to interior by sampling in the interior and along the edges of 68 crop fields. We used these data to evaluate the relative effects of farming practices within the sampled field (e.g. herbicide, fertilizer use) on milkweed versus the effects of mean field size, crop diversity, hedgerow cover, and the proportion of farmland in annual crops in the surrounding landscape. Additionally, we evaluated the effects of these variables on the cover of other herbaceous plants, to identify which—if any—could benefit milkweed without increasing overall weed cover. We found more milkweed at sites surrounded by landscapes with smaller crop fields, lower crop diversity, and higher cover of annual crops. Milkweed was more likely to occur at sites surrounded by landscapes with more hedgerows. These landscape-scale effects on milkweed were often larger than those of within-field farming practices. Importantly, we found that most variables had opposite effects on milkweed relative to other plants. Thus, altering the landscape to benefit milkweed does not imply an increase in weed cover. • Monarchs need milkweed, because milkweed are the only plants monarchs lay eggs on. • We see more milkweed in farmlands with smaller fields and less diverse crops. • There is also more milkweed in farmlands with more hedgerows and annual crops. • Most variables have opposite effects on the abundance of milkweed vs. other plants. • Thus, farmland management to benefit milkweed does not increase weed cover. [ABSTRACT FROM AUTHOR]

• Farmland size increase accelerated road surface rill erosion and nutrient losses. • Reduced field boundaries altered heterogeneity and increased overland flow. • Road extension increased road sediment production and road-stream crossings. • Road surface rill erosion significantly correlated with traffic intensity. Farmland size increase (FSI), which is an increase in operational size and consolidation of fragmented croplands, is considered an effective scheme to improve agricultural productivity and reduce fertilizer use with environmental protection benefits. But FSI involving road extension can enhance rill formation on road surfaces, and increase road erosion and associated nutrient losses in a watershed. These effects have not been experimentally quantified yet. Thus, we determined the changes in road surface rill erosion and associated nutrient losses in response to FSI before (2017) and after (2018), in an intensive sugarcane production area within Nala watershed, in southern subtropics of China. We divided the watershed into three sub-watersheds (lower (S1), left (S2) and right upper (S3) regions), and surveyed three categories of roads: (i) old roads (existing roads before 2017), (ii) new roads (constructed in 2018), and (iii) old-new roads (repaired and extended old roads in 2018). The road surface rill erosion and associated nutrient losses were much higher in the lower region (S1) than the upper regions (S1 and S2) of the watershed due to variations in field density (number of farms per unit area) and traffic intensity. Field density reduced by 53 % while traffic intensity increased by 41 % after FSI. Following FSI, annual road surface rill erosion, nitrogen, phosphorus and organic carbon losses increased by 88 %, 79 %, 67 %, and 46 %, respectively. Road surface rill erosion had a significant inverse relationship with field density (R² = 0.535, P < 0.05) but positively correlated with traffic intensity (R² = 0.728, P < 0.01). The accelerated N and P losses offset the decrease in fertilizer use by 5–22 % due to FSI. Our results highlight the significance of including soil erosion in FSI scheme for environmental protection. Accelerated road erosion following FSI should be minimized by integrated soil and watershed management practices. [ABSTRACT FROM AUTHOR]