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The relationships between habitat heterogeneity and the provision of multiple ecosystem services are not well understood. This study investigates the impacts of heterogeneity in surface floodwater inundation on the productive efficiency of ecosystem service provision, and the degree to which the relative provision of these ecosystem services is evenly balanced. We analyse indicators of five services. Field data from 100 floodplain quadrats were first analysed to investigate relationships between ecosystem service indicators and floodplain hydrology. Floodplain mosaics of varying hydrological heterogeneity were then simulated using the empirical data. Simulated floodplains with higher hydrological heterogeneity were generally less efficient in providing the target indicators, because they were adapted to the particular hydrological ranges which best provided the target services. Simulated floodplains that were more heterogeneous generally provided more even levels of the target indicators by segregating provision into different habitat types. Heterogeneity in floodplain hydrology may help to balance provision of multiple ecosystem services. However, management of hydrological heterogeneity to achieve this requires a detailed understanding of the relationships between each service and habitat conditions. [ABSTRACT FROM AUTHOR]

The urban heat island is a particular challenge for tropical cities, which receive year-round high inputs of solar radiation. Plants can help mitigate elevated urban temperatures by providing shade and increasing evaporative cooling, although the resulting increase in humidity may negatively affect thermal comfort. Street trees offer particular potential for cooling urban microclimates, as well as providing other ecosystem services, because they can be integrated within dense urban street networks. However, we have little quantitative information about the role of street trees in providing regulating ecosystem services in tropical cities. In this study, we analysed hemispherical photographs extracted from Google Street View to quantify the proportion of green canopy coverage at 50 m intervals across more than 80% of Singapore's road network. Canopy coverage data were then used to estimate the proportion of annual radiation that would be blocked from reaching ground level by the canopy. Across all locations, a median of 13% of the annual diffuse and direct solar radiation was shaded, and over 70% of this shading effect was due to the tree canopy. There was significant variation between different urban landuse types, with trees providing more shade in parks and low-density low-rise areas than in industrial and higher-density residential areas. Mapping the provision of street tree ecosystem services could help to prioritise areas for new planting by identifying streets or street sections with low shading. The approach developed in this article could be readily applied to quantify the proportion of canopy coverage and proportion of solar radiation shaded across other tropical cities. The method may also be applicable in temperate cities if Google Street View photographs were collected during the growing season. [ABSTRACT FROM AUTHOR]

Cultural ecosystem services (CES) are an important benefit that habitats provide, particularly in the fragments of natural ecosystems that remain in urban areas. To manage CES we need to understand what people use habitats for, and where different activities take place. It is challenging to assess CES provision, as surveys and interviews are time consuming and can be expensive. Social media data, particularly geo-tagged photographs, are spatially explicit and contain visual information that can be used to infer cultural use. Indicators of CES derived from social media make use of existing data so may contribute useful information for rapid, cost-effective assessments of CES. In this study we develop an indicator of CES usage that is derived from photographs from an image-sharing website, at two different scales. First, we compare four small (<150 ha) urban mangrove sites in Singapore, using photograph content to classify sites according to predominant cultural use. Second, the spatial distribution of different CES was modelled within one site using MaxEnt. A resampling simulation was conducted to identify the sensitivity of the photograph classification to the number of photographs classified. Photographs of social recreation, organisms and landscapes occurred most commonly. The proportional occurrence of photograph types differed between sites depending on their characteristics. Within one site, the probability of occurrence of social recreation photographs was highest around built focal points, while photographs of organisms were more likely in the mangrove and terrestrial habitats. Classifying more than 50–70 photographs (which would take approximately 30 minutes) gave only small increases in categorisation accuracy. This tool for CES assessment rapidly provided information that would be useful for managing Singapore's mangroves. The approach could be widely applied to assess CES provision across a range of habitats and settings, helping CES to become more commonly considered in ecosystem service evaluations. [ABSTRACT FROM AUTHOR]

• Urban neighborhood green spaces provide diverse ecosystem services in a tropical city. • We analyzed public preferences for these ecosystem services in Singapore. • Temperature and air pollution reductions were strongly preferred by the public. • Noise abatement and increases of wildlife species were not significantly preferred. • Those living near nature areas did not support introducing a new green space. Urban neighborhood green spaces provide ecosystem services important for sustainable and resilient cities. We examine public preferences for these ecosystem services by conducting a discrete choice experiment in Singapore. The results showed that the public preferred the contributions of neighborhood green spaces in reducing temperature (1, 2, or 3 °C), reducing air pollution (20 or 40 %), and learning in nature. However, they did not prefer noise abatement (10, 20, or 30 dB) and increases of bird, butterfly, and native plant species. Creation of a new neighborhood green space was preferred by people living near parks, but not preferred by those living near nature areas. These results show that diverse public preferences exist for different ecosystem services provided by neighborhood green spaces. In the context of Singapore, the urban heat island effect, to be exacerbated under climate change, and air pollution are perceived to be major environmental problems mitigated by urban vegetation. [ABSTRACT FROM AUTHOR]

Summary: Tight control of the number and distribution of crossovers is of great importance for meiosis. Crossovers establish chiasmata, which are physical connections between homologous chromosomes that provide the tension necessary to align chromosomes on the meiotic spindle. Understanding the mechanisms underlying crossover control has been hampered by the difficulty in determining crossover distributions. Here, we present a microarray-based method to analyze multiple aspects of crossover control simultaneously and rapidly, at high resolution, genome-wide, and on a cell-by-cell basis. Using this approach, we show that loss of interference in zip2 and zip4/spo22 mutants is accompanied by a reduction in crossover homeostasis, thus connecting these two levels of crossover control. We also provide evidence to suggest that repression of crossing over at telomeres and centromeres arises from different mechanisms. Lastly, we uncover a surprising role for the synaptonemal complex component Zip1 in repressing crossing over at the centromere. [Copyright &y& Elsevier]