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Bumblebees are important pollinators for a wide range of crops and wild plants. Performance of their colonies depends on pollen and nectar as food resources, but flowering plants are scarce in modern agricultural landscapes. It is well‐known that semi‐natural habitats can enhance floral resources and bumblebee abundance, but the impact of different crop types and their heterogeneity at the landscape scale remains unclear. We tested the effect of two different crop types (oilseed rape [OSR] and maize) and of configurational (field border density) and compositional heterogeneity (crop diversity) on weight gain of buff‐tailed bumblebee colonies (Bombus terrestris) and the pollen diversity collected by them in 20 landscapes in Central Germany. We found that augmenting maize cover had a detrimental effect on pollen diversity collected by bumblebees, probably due to intensive management resulting in low plant diversity. This low pollen diversity translated into reduced colony growth, since colonies with high pollen diversity gained more weight than colonies with low pollen diversity. In contrast, OSR cover and configurational and compositional heterogeneity did neither affect colony growth nor pollen diversity. However, for OSR, the timing of the flowering period was important. When OSR fields had a high flower cover at the end of the OSR blooming period, colonies showed increased growth rates. Synthesis and applications. Our results complement previous laboratory studies by showing that high pollen diversity leads to better colony performance under field conditions. Therefore, the maintenance of floral diversity in agricultural landscapes is crucial to ensure that bumblebees can fulfil their nutritional needs. However, the heterogeneity of crops, at least under the currently very low levels of crop rotation, does not contribute to this aim. In contrast, crop identity and timing of mass‐flowering crops turned out to be important factors, as maize reduced pollen resources, while late blooming oilseed rape (OSR) was beneficial to bumblebee colonies. Hence, maize cover per landscape should be reduced and strategies to enhance landscape wide flower diversity, especially towards and after the end of oilseed rape bloom, should be promoted to support bumblebee colonies that provide important pollination services. Our results complement previous laboratory studies by showing that high pollen diversity leads to better colony performance under field conditions. Therefore, the maintenance of floral diversity in agricultural landscapes is crucial to ensure that bumblebees can fulfil their nutritional needs. However, the heterogeneity of crops, at least under the currently very low levels of crop rotation, does not contribute to this aim. In contrast, crop identity and timing of mass‐flowering crops turned out to be important factors, as maize reduced pollen resources, while late blooming oilseed rape (OSR) was beneficial to bumblebee colonies. Hence, maize cover per landscape should be reduced and strategies to enhance landscape wide flower diversity, especially towards and after the end of oilseed rape bloom, should be promoted to support bumblebee colonies that provide important pollination services.

ContextUrban remnant forest exists as patches scattered in an urban matrix. They are important sites for urban biodiversity conservation. Nevertheless, it is unclear how the properties of the urban matrix affect the biodiversity of remnant patches.ObjectiveUsing data surveyed from 30 urban remnant forest patches in Guiyang, China, we intended to find out whether heterogeneity of the urban matrix affects the species richness of woody plants in these patches significantly.MethodsWe used landscape indices calculated from land cover data to quantify compositional and configurational heterogeneity of the urban matrix. Then we analyzed the association between heterogeneity of the urban matrix and the species richness of woody plants in remnant forest patches using generalized linear regression models.ResultsA significant positive association between compositional heterogeneity of the urban matrix and the species richness of tree sapling/seedlings existed when the urbanization level of the urban matrix was high. Also, compositional heterogeneity of the urban matrix correlated significantly with the species richness of shrubs in patches when the change rate of urbanization level of the urban matrix was low. Configurational heterogeneity of the urban matrix could enhance the association between patch attributes and the species richness of tree sapling/seedlings and shrubs.ConclusionsHeterogeneity of the urban matrix affected the woody plant diversity of the remnant forest patches through the interaction effects with patch attributes and the urbanization level of the urban matrix. We recommend including the management of heterogeneity of the urban matrix as an essential part of works to conserve biodiversity in urban remnant forest patches.

Conserving biodiversity on farmland is an essential element of worldwide efforts for reversing the global biodiversity decline. Common approaches involve improving the natural component of the landscape by increasing the amount of natural and seminatural habitats (e.g., hedgerows, woodlots, and ponds) or improving the production component of the landscape by increasing the amount of biodiversity‐friendly crops. Because these approaches may negatively impact on economic output, it was suggested that an alternative might be to enhance the diversity (compositional heterogeneity) or the spatial complexity (configurational heterogeneity) of land cover types, without necessarily changing composition. Here, we develop a case study to evaluate these ideas, examining whether managing landscape composition or heterogeneity, or both, would be required to achieve conservation benefits on avian diversity in open Mediterranean farmland. We surveyed birds in farmland landscapes of southern Portugal, before (1995–1997) and after (2010–2012) the European Union's Common Agricultural Policy (CAP) reform of 2003, and related spatial and temporal variation in bird species richness to variables describing the composition, and the compositional and configurational heterogeneity, of the natural and production components of the landscape. We found that the composition of the production component had the strongest effects on avian diversity, with a particularly marked effect on the richness of farmland and steppe bird species. Composition of the natural component was also influential, mainly affecting the richness of woodland/shrubland species. Although there were some effects of compositional and configurational heterogeneity, these were much weaker and inconsistent than those of landscape composition. Overall, we suggest that conservation efforts in our area should focus primarily on the composition of the production component, by striving to maximize the prevalence of biodiversity‐friendly crops. This recommendation probably applies to other areas such as ours, where a range of species of conservation concern is strongly associated with crop habitats. We examined the relative importance of landscape composition versus heterogeneity on bird diversity in Mediterranean farmland. The composition of the production component (e.g., crops and pastures) showed the strongest effects, but the composition of the natural component (e.g., woodland and shrubland habitats) was also influential. The diversity (compositional heterogeneity) and the spatial complexity (configurational heterogeneity) of land cover types showed relatively small and inconsistent effects. Maintaining biodiversity‐friendly crops is key to bird conservation in Mediterranean farmland.

The dynamic and heterogeneity of the urban heat island (UHI) is the result of the interactions between biotic, physical, social, and built components. Urban ecology as a transdisciplinary science can provide a context to understand the complex social–biophysical issues such as the thermal environment in cities. This study aimed at developing a theoretical framework to elucidate the interactions between the social–biophysical patterns and processes mediating UHI. To do it, we conducted a theoretical review to delineate UHI complexity using the concept of dynamic heterogeneity of pattern, process, and function in UHI phenomenon. Furthermore, a hypothetical heterogeneity spiral (i.e., driver-outcome spiral) related to the UHI was conceived as a model template. The adopted theoretical framework can provide a holistic vision of the UHI, contributing to a better understanding of UHI’s spatial variations in long-term studies. Through the developed framework, we can devise appropriate methodological approaches (i.e., statistic-based techniques) to develop prediction models of UHI’s spatial heterogeneity.

Soil heterogeneity affects terrestrial plant communities both directly and indirectly. In nature, the exploration of the role of heterogeneity is made difficult because any co-varying factors (nutrients, soil depth, etc.) render it problematic to clearly link cause and effect. Attributing changes specifically to heterogeneity is facilitated if heterogeneity is varied in a controlled manner and other possible confounding factors are kept constant. The experiments conducted in such a way have up till now only considered heterogeneity in two dimensions, horizontally or vertically. In this methodological study, we present a novel technique that enables researchers to vary both qualitative and configurational heterogeneity in three dimensions by building up the soil cell by cell in experimental mesocosms. We illustrate the technique with an experiment where we test the effect of cell size (i.e. configurational heterogeneity) on the performance of grassland species that vary in nutrient preference (high N and low N species). Cell size did not affect aboveground biomass but modified species richness, both at the mesocosm and the patch scale, with most species being found when cells were small yet distinct (cell size 12 cm). High N species had significantly greater aboveground biomass and species richness than low N species, both on nutrient rich and nutrient poor cells. Remarkably, those differences disappeared when plants grew on the mesocosms with cell size close to zero. By allowing greater complexity in the design of experimental mesocosms, the 3-D approach can improve understanding of the interplay between soil heterogeneity and plant and ecosystem functioning.

CONTEXT: Agricultural intensification is a leading cause of landscape homogenization, with negative consequences for biodiversity and ecosystem services. Conserving or promoting heterogeneity requires a detailed understanding of how farm management affects, and is affected by, landscape characteristics. OBJECTIVES: We assessed relationships between farming systems and landscape characteristics, hypothesising that less-intensive systems act as landscape takers, by adapting management to landscape constraints, whereas more intensive systems act as landscape makers, by changing the landscape to suit farming needs. METHODS: We mapped dominant farming systems in a region of southern Portugal: traditional cereal-grazed fallow rotations; specialization on annual crops; and specialization on either cattle or sheep. We estimated landscape metrics in 241 1-km² buffers representing the farming systems, and analysed variation among and within systems using multivariate statistics and beta diversity metrics. RESULTS: Landscape composition varied among systems, with dominance by either annual crops (Crop system) or pastures (Sheep), or a mixture between the two (Traditional and Cattle). There was a marked regional gradient of local landscape heterogeneity, but this contributed little to variation among systems. Landscape beta diversity declined from the Sheep to the Crop system, and it was inversely related to agriculture intensity. CONCLUSIONS: Less intensive farming systems appeared compatible with a range of landscape characteristics (landscape takers), and may thus be particularly suited to agri-environmental management. More intensive systems appeared less flexible in terms of landscape characteristics (landscape makers), likely promoting regional homogenization. Farming systems may provide a useful standpoint to address the design of agri-environment schemes.

Global imperatives call for reduced water consumption in homogeneous, intensive farming systems, where farmland landscape heterogeneity significantly impacts anthropogenic, ecological, and socioeconomic factors. However, the impact of this heterogeneity on crop water footprint (WF) remains uncertain. To address this, this study assessed the WF at the landscape scale across 616 subplots (1 × 1 km) in a representative county of North China Plain from 2013 to 2019, integrating green (WFgreen), blue (WFblue), and gray (WFgray) water footprints. Results showed that the winter wheat–summer maize double cropping pattern (WM) exhibited the highest WFgreen, WFblue, and WFgray. Over six years, most subplots saw significant reductions in WFgreen, WFblue, WFgray, and WF. At the landscape scale, diversification (compositional heterogeneity), fragmentation, and spatial distribution (configurational heterogeneity) were assessed using Shannon’s diversity index (SHDI), edge density (ED), and effective mesh size (MESH), which exhibited average variations of 0.07, −3.16 m ha−1, and −5.86 m2, respectively. For WM patches, the percentage of landscape (PLAND) and MESH were used to evaluate diversification and spatial distribution, resulting in reductions of 1.14% and 2.32 m2, respectively. Regression analysis and structural equation modeling further illuminated the connections between the landscape pattern and WF, emphasizing the significant role of MESH in reducing WFblue and influencing crop diversity (p < 0.001). Therefore, spatial distribution, whether directly or through the mediation of diversification, demonstrated a more substantial overall impact on WF. Consequently, future research should prioritize investigating how spatial distribution influences crop choice and agronomic management in order to determine the optimal cropping patterns and field size that strike a balance between crop production and the water footprint. This study offers theoretical guidance and a scientific foundation for redesigning farmland landscapes to bolster water sustainability in intensive farming systems.

In the current context of global urbanization, interdisciplinary research is needed to identify planning and management practices in urban green spaces (UGS) that would enhance both biodiversity and visitors' well-being. The perception of landscape heterogeneity, a core ecological concept, has been demonstrated to have a positive impact on visitors' psychological restoration. In order to apply these findings within UGS to planning and management practices, we need to characterize visitors' perception of landscape heterogeneity. We gathered data on 390 visitors' perception of landscape heterogeneity. Our results highlighted that visitors perceive landscape heterogeneity through the mixing of different heights of three vegetation strata and flower areas. Planning and management practices should enhance this landscape aspect within UGS to simultaneously promote biodiversity and visitors' psychological well-being.

In this paper, we pose a configurational optimization problem to derive the sensitivity of an arbitrary objective to arbitrary motions of one or more finite-sized heterogeneities inserted into a homogeneous domain. In the derivation, we pose an adjoint boundary value problem and utilize the adjoint fields as well as the definition of a generalized Eshelby energy-momentum tensor for arbitrary objectives to express the final result. The resulting sensitivity may be expressed as surface integrals with jump terms across the heterogeneity boundaries that vanish on homogeneous domains yielding generalized conservation laws for arbitrary objectives. We then derive the specific path-independent forms of the sensitivity of the objective to arbitrary translation, rotation or scaling of the inserted heterogeneities. We next illustrate the application of the derived sensitivities to specific objectives common to fracture mechanics as well as to structural optimization. The chosen objectives include strain energy, trade-off between structural compliance and mass, and an arbitrary objective defined entirely on the boundary of the domain. We show that for the strain energy objective, the derived sensitivities naturally yield the classical J -, L - and M -integrals of fracture mechanics. The theory is implemented within an Isogeometric computational framework for fracture modeling termed Enriched Isogeometric analysis (EIGA). The EIGA computational technique is used to optimally identify worst-case locations for line cracks that are inserted into the domain as well as to optimally mitigate the risk of fracture due to a crack at its worst-case location by sequentially inserting and optimizing the configurations of circular/elliptical stiff/soft inclusions.

Agricultural production faces the dual challenge of increasing output while ensuring efficient resource utilization and environmental sustainability amid escalating global climate change and relentless increases in human demand. This study used provincial panel data from China from 2001 to 2022 to address these challenges. It systematically evaluated the dynamic evolution of agricultural green total factor productivity (AGTFP) by selecting “resources” and “energy” as core input factors and adopting a dual-output approach focused on “economic” and “low-carbon” outcomes. This study thoroughly analyzed the synergistic mechanisms of factors such as natural endowment, agricultural technology, economic development, and environmental regulation, exploring their impact on AGTFP enhancement through the innovative application of the dynamic fuzzy-set qualitative comparative analysis (fsQCA) method. There was a significant upward trend in AGTFP across China, indicating notable progress in green agricultural development. Additionally, three pathways promoting AGTFP improvement were identified: resource–economy-driven, technology–policy-guided, and multifactor-synergy. Simultaneously, two modes constraining AGTFP enhancement were uncovered: economy–policy suppression and human capital–economy suppression, highlighting the pivotal role of regional economic development and the conditionality of converting natural resource advantages. Moreover, the contributions of these pathways to AGTFP exhibited notable temporal dynamics. Major economic events, such as the 2008 financial crisis and policy shifts, including the 2012 “Ecological Civilization” strategy, significantly altered the effectiveness of existing configurations. Our analysis of regional heterogeneity revealed distinct geographical patterns, with the resource–economy-driven model predominantly observed in central regions and the technology–policy-guided and multi-factor-synergy models more prevalent in central and eastern regions. These findings highlight the importance of formulating differentiated policies tailored to the specific needs and stages of development in different regions. Specifically, enhancing the synergy between resource management and economic development, optimizing technology–policy integration, and promoting coordinated multisectoral development are critical to fostering sustainable agricultural practices. This research provides crucial empirical evidence for shaping targeted policies that can drive green agricultural development across diverse regional contexts.