• Energy Research
• 15. Life on land close
• 6. Clean water close
• DE close
• NL close
• Sustainability close

The Urban Heat Island (UHI) is the phenomenon of altered increased temperatures in urban areas compared to their rural surroundings. UHIs grow and intensify under extreme hot periods, such as during heat waves, which can affect human health and also increase the demand for energy for cooling. This study applies remote sensing and land use/land cover (LULC) data to assess the cooling effect of varying urban vegetation cover, especially during extreme warm periods, in the city of Munich, Germany. To compute the relationship between Land Surface Temperature (LST) and Land Use Land Cover (LULC), MODIS eight-day interval LST data for the months of June, July and August from 2002 to 2012 and the Corine Land Cover (CLC) database were used. Due to similarities in the behavior of surface temperature of different CLCs, some classes were reclassified and combined to form two major, rather simplified, homogenized classes: one of built-up area and one of urban vegetation. The homogenized map was merged with the MODIS eight-day interval LST data to compute the relationship between them. The results revealed that (i) the cooling effect accrued from urban vegetation tended to be non-linear; and (ii) a remarkable and stronger cooling effect in terms of LST was identified in regions where the proportion of vegetation cover was between seventy and almost eighty percent per square kilometer. The results also demonstrated that LST within urban vegetation was affected by the temperature of the surrounding built-up and that during the well-known European 2003 heat wave, suburb areas were cooler from the core of the urbanized region. This study concluded that the optimum green space for obtaining the lowest temperature is a non-linear trend. This could support urban planning strategies to facilitate appropriate applications to mitigate heat-stress in urban area.

The number and sizes of informal settlements are expected to increase drastically in the future, and dramatically so in Sub-Saharan Africa, where migration from rural to urban areas is increasing, and poverty and food insecurity threaten livelihoods. Data sources explaining livelihood factors in informal settlements are scarce, and often highly disputed. In this study, Kibera is investigated, one of the largest informal settlements in Africa. The main aim is to analyze differences in livelihood factors across the villages in Kibera, and to explain some of the existing discrepancies in food security levels among its population. In particular, livelihood factors such as tribe, welfare and trust can explain some of the variation in food security across 12 of the 13 villages located in Kibera. The analyses inform of significant differences across the villages when it comes to, among others, income, food insecurity, ownership of land in rural areas, tribal background and trust levels in strangers and community leads. To reach the millions of people living in informal settlements now, and increasingly so in the future, it is advised that research and implementation go hand in hand, with enhanced understanding of the complexities within rural–urban food systems to ensure solutions that are affordable and accessible to low-income groups. On this pathway to fight poverty and hunger in the future, today’s policies and programs must take such complexities into account to positively contribute to strengthening the resiliency and sustainability of rural–urban food systems by ensuring an increase in welfare levels with zero climate impact.

Vegetation indicators and spatial distribution characteristics are the core and basis to study the complex human-natural coupled system. In this paper, with Landsat 5 and Landsat 8 remote sensing data, we quantitatively estimated vegetation coverage in Henan Province, China. According to the urbanization rate, altitude, slope degree, and slope exposure, we analyzed spatial and temporal variation laws of vegetation coverage under the action of different factors to provide a reference for the improvement of the ecological environment and the quality assessment of Chinese granary. From 2000 to 2013, the vegetation coverage in Henan Province declined by 30.49% and the ecological environment deteriorated. The spatial change of vegetation coverage was evenly distributed in Henan Province. The vegetation coverage was increased in the west, south, and southwest parts of Henan Province and slightly decreased in the central, east, and the eastern part of Taihang Mountain. Vegetation coverage in a city was related to its population urbanization rate. The population urbanization rate was often negatively correlated with the vegetation coverage. According to the results of terrain factors based analysis, the low-altitude areas were in a good vegetation cover condition with the high vegetation coverage grade; the areas with a smaller slope degree had the large vegetation coverage and the coverage decreased with the increase in the slope degree; the coverage showed no significant difference between sunny and shady slopes and was less limited by light, temperature, and humidity.

Background: Temperate agroforestry is regarded as a sustainable alternative to monoculture agriculture due to enhanced provisioning of ecosystem services. Plant health and food safety are crucial requirements for sustainable agriculture; however, studies of fungal diseases and mycotoxin contamination of crops grown under temperate agroforestry are lacking. This study therefore aimed to compare fungal colonization and mycotoxin contamination of crops grown in temperate agroforestry against conventional monoculture. Methods: The biomass of plant pathogenic fungi in oilseed rape plants and barley and wheat grain harvested in 2016 to 2018 at four paired agroforestry and monoculture sites was quantified using species-specific real-time PCR. Mycotoxin content of barley and wheat grain was determined by HPLC-MS/MS. Results: The colonization of oilseed rape plants with the vascular pathogen Verticillium longisporum and wheat grain with the head blight pathogen Fusarium tricinctum was lower in agroforestry than in conventional monoculture. Mycotoxin content of barley and wheat grain did not differ between agroforestry and monoculture systems and did not exceed the legal limits of the EU. Remarkably, fumonisin B1 was detected in wheat grains at two sites in two years, yet the low levels found do not raise food safety concerns. No differences were found between the two production systems with regard to infection of wheat and barley grain with five Fusarium species (F. avenaceum, F. culmorum, F. graminearum, F. poae, and F. proliferatum) and oilseed rape with fungal pathogens Leptosphaeria biglobosa, Leptosphaeria maculans, and Sclerotinia sclerotiorum. Conclusions: Temperate agroforestry does not negatively affect the infection of wheat, barley and oilseed rape with major fungal pathogens though it may suppress the infection of oilseed rape with V. longisporum and wheat grain with F. tricinctum. Furthermore, temperate agroforestry does not increase mycotoxin contamination of barley and wheat. Therefore, temperate agroforestry does not negatively affect food safety.

As a consequence of climate change and urbanization, many cities will have to deal with more flooding and extreme heat stress. This paper presents a framework to maximize the effectiveness of Nature-Based Solutions (NBS) for flood risk reduction and thermal comfort enhancement. The framework involves an assessment of hazards with the use of models and field measurements. It also detects suitable implementation sites for NBS and quantifies their effectiveness for thermal comfort enhancement and flood risk reduction. The framework was applied in a densely urbanized study area, for which different small-scale urban NBS and their potential locations for implementation were assessed. The overall results show that the most effective performance in terms of flood mitigation and thermal comfort enhancement is likely achieved by applying a range of different measures at different locations. Therefore, the work presented here shows the potential of the framework to achieve an effective combination of measures and their locations, which was demonstrated on the case of the Sukhumvit area in Bangkok (Thailand). This can be particularly suitable for assessing and planning flood mitigation measures in combination with heat stress reduction.

Regional flood frequency analysis (RFFA) is a powerful method for interrogating hydrological series since it combines observational time series from several sites within a region to estimate risk-relevant statistical parameters with higher accuracy than from single-site series. Since RFFA extreme value estimates depend on the shape of the selected distribution of the data-generating stochastic process, there is need for a suitable goodness-of-distributional-fit measure in order to optimally utilize given data. Here we present a novel, least-squares-based measure to select the optimal fit from a set of five distributions, namely Generalized Extreme Value (GEV), Generalized Logistic, Gumbel, Log-Normal Type III and Log-Pearson Type III. The fit metric is applied to annual maximum discharge series from six hydrological stations along the Sava River in South-eastern Europe, spanning the years 1961 to 2020. Results reveal that (1) the Sava River basin can be assessed as hydrologically homogeneous and (2) the GEV distribution provides typically the best fit. We offer hydrological-meteorological insights into the differences among the six stations. For the period studied, almost all stations exhibit statistically insignificant trends, which renders the conclusions about flood risk as relevant for hydrological sciences and the design of regional flood protection infrastructure.

Africa has experienced unprecedented growth across a range of development indices for decades. However, this growth is often at the expense of Africa’s biodiversity and ecosystems, jeopardizing the livelihoods of millions of people depending on the goods and services provided by nature, with broader consequences for achieving the United Nations Sustainable Development Goals. Encouragingly, Africa can still take a more sustainable path. Here, we synthesize the key learnings from the African Ecological Futures project. We report results from a participatory scenario planning process around four collectively-owned scenarios and narratives for the evolution of Africa’s ecological resource base over the next 50 years. These scenarios provided a lens to review pressures on the natural environment, through the drivers, pressures, state, impacts, and responses (DPSIR) framework. Based on the outcomes from each of these steps, we discuss opportunities to reorient Africa’s development trajectories towards a sustainable path. These opportunities fall under the broad categories of “effective natural resource governance”, “strategic planning capabilities”, “investment safeguards and frameworks”, and “new partnership models”. Underpinning all these opportunities are “data, management information, and decision support frameworks”. This work can help inform collaborative action by a broad set of actors with an interest in ensuring a sustainable ecological future for Africa.