Agricultural Mosaic Research Articles

The effect of habitat disturbance on the abundance of nocturnal lemur species on the Masoala Peninsula, northeastern Madagascar.

Madagascar is one of the world's biodiversity hotspots. The island's past and current rates of deforestation and habitat disturbance threaten its plethora of endemic biodiversity. On Madagascar, tavy (slash and burn agriculture), land conversion for rice cultivation, illegal hardwood logging and bushmeat hunting are the major contributors to habitat disturbance. Understanding species-specific responses to habitat disturbance across different habitat types is crucial when designing conservation strategies. We surveyed three nocturnal lemur species in four forest types of varying habitat disturbance on the Masoala Peninsula, northeastern Madagascar. We present here updated abundance and density estimates for the Endangered Avahi mooreorum and Lepilemur scottorum, and Microcebus sp. Distance sampling surveys were conducted on 11 transects, covering a total of 33km after repeated transect walks. We collected data on tree height, bole height, diameter at breast height, canopy cover and tree density using point-quarter sampling to characterise the four forest types (primary lowland, primary littoral, selectively logged and agricultural mosaic). Median encounter rates by forest type ranged from 1 to 1.5 individuals (ind.)/km (Microcebus sp.), 0-1 ind./km (A. mooreorum) and 0-1 ind./km (L. scottorum). Species density estimates were calculated at 232.31 ind./km2 (Microcebus sp.) and 121.21 ind./km2 (A. mooreorum), while no density estimate is provided for L. scottorum due to a small sample size. Microcebus sp. was most tolerant to habitat disturbance, exhibiting no significant effect of forest type on abundance. Its small body size, omnivorous diet and generalised locomotion appear to allow it to tolerate a variety of habitat disturbance. Both A. mooreorum and L. scottorum showed significant effects of forest type on their respective abundance. This study suggests that the specialist locomotion and diet of A. mooreorum and L. scottorum make them susceptible to the effects of increasing habitat disturbance.

Old fields increase habitat heterogeneity for arthropod natural enemies in an agricultural mosaic

Spatially heterogeneous agricultural landscapes can support high levels of biodiversity. However, our understanding of the biodiversity value of most landscape elements and their role in the farmland mosaic is limited. We assessed the potential of old fields, a common small-scale feature of farmland in the Cape Floristic Region (CFR), for maintaining arthropod natural enemy (NE) diversity. We also assessed how habitable they are to NEs occurring in remnant fynbos vegetation, compared to the dominant surrounding vineyards. Furthermore, we compared habitat preferences of hymenopteran parasitoids, which are mostly habitat and trophic specialists, with those of generalist predatory arthropods. NE abundance and richness was as high in old fields as in natural vegetation, and was significantly higher than in vineyards. Old fields provided high plant diversity and prey abundance which were positively correlated with NE diversity. Ten out of eleven species of conservation significance assessed here occurred in old fields, including Western Cape and South African endemics, rare and uncommon species. Old field assemblages complemented fynbos and vineyard assemblages, and contained many unique species. They also shared many more species with natural assemblages than did vineyards, representing a more habitable transformed landscape element than cultivated areas for most species. Parasitoids showed greater habitat specificity than predators, and are likely to benefit more from the positive effect of increased habitat heterogeneity. Our results show that small-scale non-natural landscape features can provide additional resources, increase compositional heterogeneity and may help soften the overall agricultural mosaic for arthropod NEs in the CFR. Understanding the value of different landscape mosaic elements is an important step towards a broader landscape-scale approach to farmland biodiversity conservation.

Anthropogenic impacts on Costa Rican bat parasitism are sex specific.

While anthropogenic impacts on parasitism of wildlife are receiving growing attention, whether these impacts vary in a sex‐specific manner remains little explored. Differences between the sexes in the effect of parasites, linked to anthropogenic activity, could lead to uneven sex ratios and higher population endangerment. We sampled 1108 individual bats in 18 different sites across an agricultural mosaic landscape in southern Costa Rica to investigate the relationships between anthropogenic impacts (deforestation and reductions in host species richness) and bat fly ectoparasitism of 35 species of Neotropical bats. Although female and male bat assemblages were similar across the deforestation gradient, bat fly assemblages tracked their hosts closely only on female bats. We found that in female hosts, parasite abundance per bat decreased with increasing bat species richness, while in male hosts, parasite abundance increased. We hypothesize the differences in the parasite–disturbance relationship are due to differences in roosting behavior between the sexes. We report a sex‐specific parasite–disturbance relationship and argue that sex differences in anthropogenic impacts on wildlife parasitism could impact long‐term population health and survival.

Extent to which an agricultural mosaic supports endemic species-rich grasshopper assemblages in the Cape Floristic Region biodiversity hotspot

The impact of expansion and intensification of agriculture on biodiversity requires quantification, especially in areas of exceptionally high biodiversity like the Cape Floristic Region (CFR). In the CFR, landscape mosaics consist of agriculture alongside Mediterranean-type fynbos scrubland natural vegetation rich in endemic insect species. However, little is known about how ground-dwelling insect herbivores utilize the various elements of the mosaic. We compared species richness, abundance, species composition, diversity and evenness of grasshoppers among 46 sites in four geographical areas in the CFR. We investigated three land-use types: fynbos (the historic condition as reference), vineyards and deciduous fruit orchards, the main production types in the region. Grasshopper abundance was significantly higher in vineyards than in fynbos or orchards. Species richness, diversity, and evenness were highest in fynbos followed by vineyards and then orchards. Orchards had no unique species, vineyards two, and fynbos 14 unique species. Nevertheless, there was overall high species similarity among all three land-use types, with high species assemblage similarities between vineyards and orchards. Species that preferred fynbos were mostly flightless and endemic to the CFR. We show that agricultural areas do not support the entire species assemblage of natural vegetation, although vineyards are more diverse than orchards, probably because of the presence of often grassy ground cover and an open canopy. Vineyards provide the greatest opportunity for improved harmony between production and biodiversity conservation through continuing to improve the ground cover quality and other farming practices. Fewer opportunities are provided by orchards in view of their closed canopy and absence of grassy ground cover (for generalist species) and fynbos plants (for endemic species). However, protected areas still remain vital for maintaining the full complement of species, especially flightless endemics.

Linking landscape futures with biodiversity conservation strategies in northwest Iberia — A simulation study combining surrogates with a spatio-temporal modelling approach

The most prominent factors inducing landscape change in the rural regions of south west Europe are depopulation and the associated socio-ecological modifications. The aim of this work was to assess the future implications of these processes on land use/land cover and biodiversity in northwest Iberia. To achieve our goal, we developed a virtual spatially explicit dynamic model to simulate regional socio-ecological dynamics. For the period between 1960 and 2040, we tested four different environmental scenarios ranging from small decreases in conifer forest and a stabilization of agricultural areas and shrublands to more radical shifts, substantial decreases in agricultural areas and massive expansion of eucalyptus stands. The model considers also fire, whose role increased significantly in the scenarios of expanded forests. Bird assemblages, which we used as a surrogate for biodiversity, showed complex patterns although with overall decreases in richness and abundance. Species with narrow niche and from Mediterranean open habitats were particularly sensitive to the ongoing changes simulated. Our results suggest that landscape management actions and planning assessments designed for conserving biodiversity should focus on the maintenance of the traditional agricultural mosaic combined with a regulatory legislation limiting the expansion of fast growing tree forests (e.g Eucalyptus stands). This strategy can contribute to maintaining a diversity of land use/land cover in a heterogeneous landscape and the prevention of the occurrence of large wildfires, fundamental for the implementation of national biodiversity strategies and action plans.

The use of fynbos fragments by birds: Stepping-stone habitats and resource refugia

Fynbos habitats are threatened by fragmentation through land use and anthropogenic changes in fire regimes, leading to a loss of suitable habitat for birds. We investigated the response of fynbos-typical avifauna to fragmentation and postfire vegetation age in order to better understand the consequences of these processes for bird communities. Vegetation composition and bird inventory data were collected along wandering transects in three South Outeniqua Sandstone Fynbos habitat configurations: fragmented patches (associated with anthropogenically driven habitat loss < 150 years ago), naturally isolated fynbos islands (formed through climate-driven forest expansion in the Holocene) and extensive areas of relatively pristine habitat known as ‘mainland’. The latter configurations served as references against which to investigate bird and vegetation responses to more recent habitat fragmentation. Linear regressions were used to compare the relationships of a number of bird and plant species to areas between each habitat configuration. Bird attribute frequency data were compared between habitat configurations using chi-square tests. Birds and plants showed significant species–area relationships in natural island and mainland sites, but no such relationship occurred in artificial fragments for birds, where the surrounding anthropogenic land uses are likely to have contributed generalist or colonist species. Avifaunal migratory groups were not affected by isolation distances of > 10 km in this study and their frequencies were the same across the three habitat configurations. Certain feeding guilds did, however, respond to postfire vegetation age, with nectarivore species twice as likely to occur in oldgrowth mainland fynbos. Fragmentation can alter fire disturbance regimes, which in turn alter the availability of resources in a habitat, so the impacts of fragmentation on birds are probably indirect through changes in the vegetation component.Conservation implications: Fragments of South Outeniqua Sandstone Fynbos have value as resource refugia and ‘stepping-stone’ reserves for avifauna. Fragments should be managed for vegetation age to ensure that at least some patches sustain high levels of nectarproducing plant species. Fire management should, however, factor in both plant and bird requirements.Keywords: Avifauna; Agricultural Mosaic; Cape Floristic Region; Conservation; Habitat Fragmentation; Species-Area Relationships

Anthropogenic and topographic correlates of natural vegetation cover within agricultural landscape mosaics in Turkey

Natural vegetation enhances the value of agricultural landscapes for people and wildlife. However, the role of anthropogenic versus topographic factors in driving the extent of natural vegetation cover within agricultural lands at large spatial scales remains unexplored. I assessed the influence of anthropogenic and topographic variables on the extent of agricultural mosaics with high natural vegetation cover in the country of Turkey where a large extent of natural and semi-natural vegetation is maintained by traditional agriculture. GIS layers depicting human land use, elevation, slope, roads and population data were obtained and summarized at two spatial scales, within provinces and for 100km2 grid cells covering the country’s entire agricultural land area. Average farm size was also obtained at province level. Hierarchical Partitioning was conducted to determine the independent effect of anthropogenic and topographic variables on the variation in agriculture with high natural vegetation. Slope had the largest independent effect on the variation in the proportion of agricultural mosaic with high natural vegetation cover. The extent of agricultural and settlement area also explained much of the variation in natural vegetation across both grid cells and provinces. The proportion of natural vegetation increased as human population and road density decreased across grid cells and as average farm size decreased across provinces. These results suggest that while topography is the primary driver of natural vegetation cover within agricultural mosaics in Turkey, the pressures associated with urban development and agricultural industrialization may also influence the cultural and wildlife value of agricultural landscapes.

Spatiotemporal variation in resource selection of servals: insights from a landscape under heavy land-use transformation

Abstract Changes in habitat composition and structure along natural agricultural habitat gradient affect spatial ecology of carnivores at both intraspecific and interspecific levels. An important prerequisite for the conservation and management of habitat specialists is a sound understanding of how they use indigenous habitats within fragmented landscapes. We present the 1st comprehensive study on home range, overlap, and resource selection of 16 radiocollared servals ( Leptailurus serval ) in the Drakensberg Midlands, South Africa. Servals (11 males and 5 females) were livetrapped and radiotracked between May 2013 and August 2014 covering 4 seasons (winter, spring, summer, and autumn). Mean annual home range estimates (95% and 50% fixed kernel [FK], respectively) for males (38.07 km 2 ; 8.27 km 2 ) were generally larger than for females (6.22 km 2 ; 1.04 km 2 ). Although male core ranges varied slightly in spring, overall serval home ranges were stable across seasons. There was considerable intersexual home range overlap (> 85%), whereas intrasexual overlap was rare (< 10%). Home range size decreased with increase in age and less availability of wetland, while it increased in males at both levels (95% FK and 50% FK). For both sexes, Manley’s selection index indicated that natural habitats including wetlands and forest with bushland ranked higher than all other habitat classes. However, forested habitat was used approximately 2 times more frequently by males than females whereas cropland was avoided by both sexes. Overall, wetlands were ranked highest, followed by forest with bushland, grassland, plantations, and cropland in terms of serval resources selection. Our results emphasize that natural habitats, mainly wetlands and forests with bushland, are important predictors of spatiotemporal habitat use of servals in the agricultural mosaics of South Africa.

Effects of converted grassland on Hemiptera assemblages in surrounding rice fields

AbstractEstablishment of pastures for cattle grazing adjacent to rice crops may increase the abundance of rice pests, because some cultivated grass species are host plants to these insects. In this study, we investigated assemblages of Hemiptera potentially causing pecky rice in paddy fields in Japan, and the effects of converted grasslands on surrounding rice fields. We systematically sampled Hemiptera in five land‐use types, comprising riverside vegetation, rice fields, forage rice paddies, fallow fields and pasture in a fine‐scale agricultural mosaic. We also examined the abundance of the two main rice bug species, in relation to the proportion of pecky rice and distance to pasture. Converted pastures that contained cultivated bahia grass (Paspalum notatum Flügge) and Italian ryegrass (Lolium multiflorum Lam.), had the greatest abundance of three rice bug species; Stenotus rubrovittatus (Matsumura), Trigonotylus caelestialium (Kirkaldy) and Cletus punctiger (Dallas). The percentage of damaged pecky grains was significantly greater in rice fields near pasture (within 200 m) than in those farther away. Our study provides evidence that the main source of rice bugs in agricultural croplands was pasture; and suggests that managing food sources for these insect pests in pastures close to rice paddies could help reduce their detrimental impact on rice crops.

Structural complexity of arthropod guilds is affected by the agricultural landscape heterogeneity generated by fencerows

Intensive farming imposes harsh conditions impeding the persistence of most arthropod species within crop fields. Hence, arthropods surviving the unfavourable conditions prevailing within crop fields may disperse towards nearby uncropped margins, such as fencerows. Here, we evaluate the influence of landscape heterogeneity on the abundance of different guilds, particularly herbivores and their natural enemies. Said heterogeneity mostly derives from fencerow network density. Hence, we developed an approach based on fitting linear-mixed models to elucidate the effects of landscape heterogeneity and field position (fencerows and crop interiors) on arthropod diversity. Mixed models were fitted to arthropod data obtained by pitfall trap samplings in 36 crop fields. Arthropod communities were structurally and functionally more complex along fencerows than within nearby crop interiors. Arthropods abundance was modulated by landscape heterogeneity, increasing the abundance of natural enemies as the landscape heterogeneity increased. On the contrary, herbivores abundance decreased as landscape heterogeneity increased. Consequently, the ratio between herbivores and natural enemies also decreased as landscapes became more heterogeneous. Natural enemies with larger body sizes, mostly carabid beetles, were more sensitive to landscape homogenisation. Our study reveals that, despite the coarse-grained landscapes in the Rolling Pampa, fencerow density appears as a key factor for structuring complex arthropod guilds in intensively farmed agricultural mosaics. In landscapes with higher density of fencerows, arthropods tend to concentrate along them, thus increasing the community structural complexity as well as the predation pressure over herbivores. This structural complexity of upper trophic levels enhances the ‘top-down’ regulation of herbivore populations, consequently decreasing the probability of pest outbreaks within crop fields.

Confluence of the Morava and Dyje Rivers: a century of landscape changes in maps

ABSTRACTThe area of the Morava and Dyje Rivers confluence is one of the most biologically diverse localities in the Czech Republic, recognised under many international forms of nature protection. In this paper we analyse and present land use/land cover (LULC) changes that took place over the last century. Using aerial photographs from the years 1938, 1953, 1976 and 2009, we differentiate 24 categories of LULC with a special focus on forest management. The most important detected changes are (i) closure of open/structured woodlands, (ii) change from an agricultural mosaic into large-field arable land, (iii) regulation of water courses, (iv) decrease in grassland area and (v) increase in forest logging intensity. LULC trends in this area differ significantly from the general LULC development within the Czech Republic. The results are presented in six map sheets showing LULC in (a–d) the studied years, (e) processes of LULC changes and (f) LULC change intensity. The thematic maps are accompanied by aerial photographs selected to show characteristic features of landscape structure in a certain period and by graphs including those visualising landscape metrics.

Turnover in bee species composition and functional trait distributions between seasons in a tropical agricultural landscape

A comprehensive understanding of how spatial variation across landscapes regulates local abundances and species richness also needs to consider possible temporal changes in such relationships. In many tropical areas, the contrast between dry and rainy season is pronounced and the types and distributions of the main floral resources differ (herbs vs trees). This shift in resources could result in different pollinator abundances, species richness and trait compositions between seasons, as well as in how these components are spatially distributed. We compared the bee species composition between dry and rainy season in an agricultural mosaic landscape in southwestern Ethiopia, and analyzed it in relation to forest cover. We sampled bees for 67 days in the dry season and 86 days in the rainy season with pan and vane traps in 28 homegardens covering a gradient from low to high tree cover in the surrounding area. We found a clear shift in species composition between seasons, with more small bee species and more below-ground nesting bees in the rainy season compared to the dry season. The distribution of height at which the bees were foraging shifted between seasons with a higher proportion of the bees foraging at tree level in the dry season. Bee abundance and richness were generally positively affected by higher forest cover surrounding the homegardens, but there were no clear interaction effects between seasons, in contrast to our hypothesis. The clear turnover in species composition between seasons and the positive effect of forest cover show that mechanisms acting both at spatial and temporal scales are important in regulating local bee communities.

Revealing Regional Deforestation Dynamics in North-Eastern Madagascar—Insights from Multi-Temporal Land Cover Change Analysis

The north-eastern escarpment of Madagascar harbours the island’s last remaining large-scale humid forest massifs surrounded by a small-scale agricultural mosaic. There is high deforestation, commonly thought to be caused by shifting cultivation practiced by local land users to produce upland rice. However, little is known about the dynamics between forest and shifting cultivation systems at a regional level. Our study presents a first attempt to quantify changes in the extent of forest and different agricultural land cover classes, and to identify the main dynamics of land cover change for two intervals, 1995–2005 and 2005–2011. Over the 16-year study period, the speed of forest loss increased, the total area of upland rice production remained almost stable, and the area of irrigated rice fields slightly increased. While our findings seem to confirm a general trend of land use intensification, deforestation through shifting cultivation is still on the rise. Deforestation mostly affects the small forest fragments interspersed in the agricultural mosaic and is slowly leading to a homogenization of the landscape. These findings have important implications for future interventions to slow forest loss in the region, as the processes of agricultural expansion through shifting cultivation versus intensified land use cannot per se be considered mutually exclusive.

Impact of land cover homogenization on the Corncrake (Crex crex) in traditional farmland

The loss of landscape heterogeneity is causing declines of farmland biodiversity around the world. Traditional farmland regions are often highly heterogeneous and harbor high biodiversity, but are under threat of land cover homogenization due to changing agricultural practices. One species potentially affected by landscape homogenization is the Corncrake (Crex crex), which is threatened in Western Europe but remains widespread in the traditional farmland regions of Eastern Europe. In this study we present a case study aiming to assess the potential threat of landscape homogenization for the Corncrake in Romania. We first examined current Corncrake distribution in relation to woody vegetation cover, landscape heterogeneity, and topography (measured at three different spatial scales), as well as human disturbance, throughout the existing agricultural mosaic. Second, we predicted potential future distribution of suitable Corncrake habitat in response to land cover homogenization by simulating a reduction in land cover diversity. Corncrakes were present in grassland and arable fields, and preferentially occupied remote areas that were wet and flat, and had high land cover diversity at the 100 ha scale. The simulation of land cover diversity loss revealed that even a moderate reduction of land cover diversity could drastically reduce the extent of suitable Corncrake habitat. Our findings show the high conservation value of traditional heterogeneous farmland for the Corncrake. Therefore, to protect the Corncrake in traditional farmland, pro-active policy measures should encourage the continuation of mixed farming practices to maintain a diversity of land covers.

Feedingbehaviour of the dawn bat (<i>Eonycteris spelaea</i>) promotes cross pollination of economically important plants in Southeast Asia

Eonycteris spelaea is recognized as the principal pollinator of most chiropterophilous plants in SE Asia. The present study describes its feeding behaviour and clarifies its role in cross pollinating these highly self-incompatible plants. Ten individuals of E. spelaea were radio-tracked during the flowering period of durian (Durio zibethinus) and petai (Parkia speciosa) in an agricultural mosaic in southern Thailand. Eonycteris spelaea makes a mean of seven visits per hour to these trees and 80-86% of each feeding bout involves visits to multiple conspecific trees. During each visit, 93% of D. zibethinus stigmas and 50% of P. speciosa stigmas were loaded with conspecific pollen. Eonycteris spelaea was the most common bat visitor to the trees. High visitation frequency and conspecific pollen deposition by E. spelaea to D. zibethinus and P. speciosa indicates that this nectarivorous bat is an effective pollinator. Mixed planting of chiropterophilous trees in fruit orchards is recommended to ensure regular visits of E. spelaea. Protecting natural roost caves of E. spelaea is also essential in order to maintain the vital ecosystem service provided by these bats.

Vegetation coverage change in the EU: patterns inside and outside Natura 2000 protected areas

EU conservation policy is primarily based on the Natura 2000 network of protected areas (PAs). We analyzed the land-cover changes between 2000 and 2006 inside 25,703 Natura 2000 sites in 24 EU Member States, and compared them with those observed outside the PAs. At the EU level, ‘Artificial surfaces’ and ‘Agricultural areas’ exhibit lower rates of transformation within PAs than outside. ‘Forests and semi-natural areas’ marginally increased inside PAs, while they marginally decreased outside. In States that joined the EU before 2000, landscape transformation rates were low, and inside PAs ‘Forest’ preservation was accompanied with a shift from intensive agricultural practices ‘Permanent arable land’ to more diverse ‘Agricultural mosaics’. In new Member States (most of them located in Eastern Europe), there was agricultural abandonment, with conversion to ‘Artificial surfaces’ or ‘Natural vegetation’, both within and outside PAs. Broad scale EU policies (like the Common Agricultural Policy) and socio-economic drivers (like the transition from planned to market economy) seem to be dominant factors in explaining land-cover transformations, while conservation policies may moderate these trends inside PAs.

Plant diversity in a changing agricultural landscape mosaic in Southern Transylvania (Romania)

Traditional agricultural landscapes represent mosaics of land use covers that often support high species diversity. Many Eastern European countries contain large areas of High Nature Value (HNV) farmland. However, these landscapes are likely to change under current EU regulations and global market pressure, with potentially negative consequences for biodiversity. The conservation value of Romania’s grasslands is widely recognized, but the potential conservation value of other parts of the landscape mosaic has not been assessed to date. For this reason, we sought to assess patterns of plant diversity across the entire landscape mosaic. We sampled vascular plants at 139 sites (comprising 8 plots of 1m2/ha) in forest (n=23), grassland (n=57) and within the arable mosaic (n=59). To examine potential differences in species richness and composition between these land cover types, we used analysis of variance and detrended correspondence analysis. We also modeled total species richness, richness of HNV indicator plants and richness of arable weeds in response to variables representing topography as well as structural and configurational heterogeneity. Species composition differed strongly between grassland, the arable mosaic and forests. Richness was highest in grasslands, but surprisingly, the arable mosaic and grassland contributed similarly to the cumulative number of recorded species. Models of species richness revealed a wide range of responses of plant groups to topographical conditions and to structural and configurational heterogeneity, which often differed between land use types. Plants were affected by conditions measured at both local (1ha) and landscape (50ha) scales. Noting the substantial, and hitherto under-recognised, contribution of the agricultural mosaic to regional-scale plant diversity, we recommend consideration of the entire landscape mosaic in future conservation schemes.

Deriving a per-field land use and land cover map in an agricultural mosaic catchment

Abstract. Detailed data on land use and land cover constitute important information for Earth system models, environmental monitoring and ecosystem services research. Global land cover products are evolving rapidly; however, there is still a lack of information particularly for heterogeneous agricultural landscapes. We censused land use and land cover field by field in the agricultural mosaic catchment Haean in South Korea. We recorded the land cover types with additional information on agricultural practice. In this paper we introduce the data, their collection and the post-processing protocol. Furthermore, because it is important to quantitatively evaluate available land use and land cover products, we compared our data with the MODIS Land Cover Type product (MCD12Q1). During the studied period, a large portion of dry fields was converted to perennial crops. Compared to our data, the forested area was underrepresented and the agricultural area overrepresented in MCD12Q1. In addition, linear landscape elements such as waterbodies were missing in the MODIS product due to its coarse spatial resolution. The data presented here can be useful for earth science and ecosystem services research. The data are available at the public repository Pangaea (doi:110.1594/PANGAEA.823677).

Improving the simulation of fine-resolution landscape changes by coupling top-down and bottom-up land use and cover changes rules

Modelling land use and cover changes (LUCC) at local and landscape scales simultaneously, in terms of composition and configuration, remains today highly challenging. Agricultural landscapes offer an illustrative context for this purpose. This article presents a modelling platform (DYPAL) able to simulate LUCC at both local (agricultural parcel, farm) and landscape levels by combining LUCC processes with an optimization algorithm. The efficiency of this approach is assessed by comparing it with an approach applying the same LUCC processes without optimization. Simulations have been developed for two representative case studies of temperate intensive agricultural mosaics: (1) neutral landscapes with simple and theoretical rules and (2) observed landscapes with realistic crop successions rules. Results show that this modelling platform improves the simulation of LUCC achieved at fine resolution, although not systematically. Improvements are observed when compared to theoretical farming practices. But, when compared with an observed landscape, it is true for one type of (arable) farms only. Several hypotheses are discussed, such as the fact that farmers possibly do not follow optimized rules. Finally, this study illustrates that the use of several indices is crucial to assess whether a simulated landscape is realistic or not, because it does not rely to the assessment of the predictive power of the model.

Agricultural mosaics maintain significant flower and visiting insect biodiversity in a global hotspot

Agricultural expansion requires mitigation to conserve biodiversity and maintain functional interactions across the transformed mosaic. Conservation outside protected areas (PAs) means providing increased spatial opportunities for populations to survive over the long-term. Here we assess the capacity of agricultural mosaics for maintaining indigenous biodiversity against the benchmark levels in neighbouring PAs. We do this in three geographical areas in the major biodiversity hotspot, the Cape Floristic Region. We focus on two functionally related groups, indigenous flowers and their associated native insects, to assess the biodiversity value of certain components of agricultural mosaics. These components include agriculturally disturbed land, semi-transformed, disturbed land, and remnant patches of natural land, as well as adjacent PAs as reference sites. Overall, species richness across the agricultural mosaics outside PAs was similar to that within PAs for insects, although more variable for plants. Nevertheless, sites outside PAs still retained great diversity of flowering plants. Across the agricultural mosaic, sites shared 20–38 % of their insect species, and 12–28 % of plant species, indicating substantial species turnover. Each particular agricultural component retained species not sampled elsewhere in the landscape, indicating that habitats outside PAs can make a significant contribution to the compositional biodiversity of an area. Our findings are positive for biodiversity conservation across these agricultural mosaics, with these semi-natural components within the production landscape, in effect, extending the size of the PAs for many species. Conservation planning should recognize the value of such agricultural mosaics.