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This paper presents a literature review on urban design indicators addressing the impact of urban geometry and vegetation on the outdoor thermal environment at the pedestrian level, as urban geometry and vegetation have been regarded as the most influential urban design factors that affect outdoor microclimate. The thermal balance concept is first introduced to elaborate how each component of energy fluxes is affected by the urban built environment, which helps to explore the underlying thermophysical mechanisms of how urban design modifies the outdoor thermal environment. The literature on numerous urban design descriptors addressing urban geometric characteristics is categorized into five groups in this paper according to the design features that the parameters entail, including land use intensity, building form, canyon geometry, space enclosure and descriptive characteristics. The literature on urban vegetation descriptors is reviewed together, followed by the combined effect of urban geometry and vegetation. This paper identifies a series of important urban design parameters and shows that the impact of design parameters on thermal environment varies with time, season, local climate and urban contexts. Contradictory impacts often occur between daytime and nighttime, or different seasons, which requests trade-offs to be achieved when proposing design strategies.

To achieve sustainable development of hydroelectric resources, it is necessary to understand their availability, variability, and the expected impacts of climate change. Current research has mainly focused on estimating hydropower potential or determining the optimal locations for hydropower projects without considering the variability and historical trends of the resources. Herein, the hydropower potential variability from reconstructed streamflow series estimated with a non-parametric gap-filling method and geographic information systems (GIS) techniques are analyzed. The relationships between hydropower and large-scale climate variability, expressed by sea surface temperature, are explored. Finally, we project hydropower potential through 2050 using 15 global circulation models with representative concentration pathway (RCP) 4.5. We used four watersheds in central Chile as a case study. The results show significant interannual and inter-basin hydropower potential variability, with decreasing trends over time modulated by alternating positive and negative decadal trends; these modulations exhibit greater intensities than the general trends and are attributable to climatic oscillations such as El Niño. Future scenarios indicate high hydropower availability and a possible over-investment in hydroelectric plants in two of the four studied watersheds. Results show the need to improve the current policies that promote hydropower development including hydropower resource variability in order to achieve optimal, sustainable hydropower development worldwide.

Ejin Oasis, located in the lower reaches of the Heihe River Basin (HRB), has experienced severe ecosystem decline between the 1960s and 1990s. In response, the Chinese Government implemented the Ecological Water Diversion Project (EWDP) in 2000. To evaluate the effects of the EWDP, this study monitored changes in land use and vegetation in the Ejin Oasis since 2000 and examined driving factors behind such changes. Results demonstrated that the Ejin Oasis ecosystem generally improved between 2000 and 2011. Water body area significantly increased. Lake area of once dried-up Sogo Nuur increased to 45 km2. Accordingly, vegetation cover restoration has also significantly increased. For example, the Seasonally Integrated Normalized Difference Vegetation Index (SINDVI) has shown that 31.18% of the entire study area experienced an increase in vegetation area. On the other hand, even though the EWDP has been successful in driving vegetation recovery and lake restoration, farmland reclamation has counteracted such restoration initiatives. Farmland area almost doubled between 2000 and 2011. Thus, farmland expansion management is necessary for the full restoration of the Ejin Oasis ecosystems as well as HRB sustainable development. The results of this study can provide a reference for the management of the HRB.

Based on the detailed analysis of sedimentology, diagenesis, and petrophysics, this study characterized the Middle-Lower Jurassic Callovian-Oxfordian carbonate reservoirs of 68 key wells in the Amu Darya Basin and assessed the controlling factors on the quality of the target intervals. We identified 15 types of sedimentary facies developed in seven sedimentary environments using sedimentary facies analysis, such as evaporative platform, restricted platform, open platform, platform margin, platform fore-edge upslope, platform fore-edge downslope, and basin facies. The target intervals went through multiple diagenetic stages, including the syndiagenetic stage, early diagenetic stage, and middle diagenetic stage, all of which had a significant impact on the reservoir quality. Main diagenetic processes include dissolution and fracturing which improve the reservoir quality as well as cementation, compaction, and pressure solution that reduce the reservoir quality. By analyzing the reservoir quality, we identified nine fluid flow units and five types of reservoir facies. Among them, the dissolved grain-dominated reservoir facies is of the highest quality and is the best storage and flow body, while the microporous mud-dominated reservoir facies of platform fore-edge downslope and open marine facies is of the lowest quality and could not become the flow unit unless it was developed by fracturing.

Experiences of wind turbines (WT) shape public perception and acceptance of the technology, influencing government policy, deployment, and land-use policies of wind turbines. This paper attempts to find changes in public perceptions over the last three decades and differences between experts and the public over different land-use options. A semi-structured questionnaire that integrates a visual survey of 10 images of WT technology in different urban, landscape and seascape settings was presented to both groups. The perceptions of siting, proximity, landscape type, and maturity of urban wind turbines’ technology in renewable energy generation were contrasted. The results revealed that both the public and experts alike significantly preferred images of WT inclusion in seascape and landscape settings and responded negatively to images of WT as an addition to buildings in urban contexts. Images of wind turbines around transport settings were ranked in the second set of acceptances, after landscape settings, indicating that closer proximity to WT is acceptable, but for a short duration. The analysis also highlighted a preference by the public for aesthetically engaging WT, even if they resulted in lower energy yields, but were less accepted by the experts who based their judgment on technical performance.

Renewable energy is predicted to play a crucial role in the energy sector as transitioning from fossil fuels to biofuels is key to achieving carbon neutrality. The comprehensive utilization of livestock manure and crop residues as a viable source of biofuels can play a significant role in Ghana’s future energy system. This current study aims to examine and predict the biofuel potential in Ghana from animal manure and crop residues. The biogas-biomethane potential of animal manure is determined using anaerobic digestion technology, whereas crop residues’ bioethanol potential is assessed using computational and analytical approaches. The findings demonstrate that animal manure biogas potential is 237.72 normal million cubic meters (NMm3). The highest manure-biogas potential per animal is from cattle (27.15 Nm3) and pigs (18.15 Nm3), while the least contribution is from chickens (1.80 Nm3). In addition, the annual bioethanol production is 3.74 gigaliters (GL), and residues from maize (0.88 GL), yams (0.82 GL), and plantains (0.47 GL) had the largest share per annum. By 2100, Ghana has the potential to produce 1288.56 NMm3 of manure-based biogas which can offset 13.88% of liquefied petroleum gas (LPG) consumption. The biogas potential positively correlates with the biomethane potential of 901.99 NMm3. Furthermore, 91.85% of the 14.76 GL of bioethanol will be from food crop residues. This study provides critical information to lawmakers and energy planners with strategies to achieve energy security and minimize the ecological footprint in an optimistic scenario.

Seismic, core, drilling, logging, and thin-section data are considered to analyze the reservoir diversity in the east, middle, and west fan of the Liushagang Formation in the steep-slope zone of the Weixinan Sag, Beibuwan Basin. Three factors primarily affect the reservoir differences for steep-slope systems: (1) Sedimentary factors mostly control reservoir scales and characteristics and the drainage system and microfacies. Massive high-quality reservoirs have shallow burial depths. Channel development and sediment supply favor the formation of these reservoirs. The sedimentary microfacies suggest fan delta plain distributary channels. (2) Lithofacies factors primarily control reservoir types and evolution. The diagenesis of high-quality reservoirs is weak, and a weak compaction–cementation diagenetic facies and medium compaction–dissolution diagenetic facies were developed. (3) Sandstone thickness factors primarily control the oil-bearing properties of reservoirs. The average porosity and permeability of high-quality reservoirs are large, the critical sandstone thickness is small, the average sandstone thickness is large, and the oil-bearing capacity is high. Furthermore, the reservoir prediction models are summarized as fan delta and nearshore subaqueous fan models. The high-quality reservoir of the fan delta model is in the fan delta plain, and the lithology is medium–coarse sandstone. The organic acid + meteoric freshwater two-stage dissolution is developed, various dissolved pores are formed, and a Type I reservoir is developed. The high-quality reservoir of the nearshore subaqueous fan model is in the middle fan, and the lithology is primarily medium–fine sandstone. Only organic acid dissolution, dissolution pores, and Type I–II reservoirs are developed. Regarding reservoir differences and models, the high-quality reservoir of the steep-slope system is shallow and large-scale, and the reservoir is a fan delta plain distributary channel microfacies. Weak diagenetic evolution, good physical properties, thick sandstone, and good oil-bearing properties developed a Type I reservoir. The study of reservoir control factors of the northern steep-slope zone was undertaken in order to guide high-quality reservoir predictions. Further, it provides a reference for high-quality reservoir distribution and a prediction model for the steep-slope system.

With the development of agricultural modernization, the carbon emissions caused by the agricultural sector have attracted academic and practitioners’ circles’ attention. This research selected the typical agricultural development province in China, Fujian, as the research object. Based on the carbon emission sources of five main aspects in agricultural production, this paper applied the latest carbon emission coefficients released by Intergovernmental Panel on Climate Change of the UN (IPCC) and World Resources Institute (WRI), then used the ordered weighted aggregation (OWA) operator to remeasure agricultural carbon emissions in Fujian from 2008–2017. The results showed that the amount of agricultural carbon emissions in Fujian was 5541.95 × 103 tonnes by 2017, which means the average amount of agricultural carbon emissions in 2017 was 615.78 × 103 tonnes, with a decrease of 13.13% compared with that in 2008. In terms of spatial distribution, agricultural carbon emissions in the eastern coastal areas were less than those in the inland regions. Among them, the highest agricultural carbon emissions were in Zhangzhou, Nanping, and Sanming, while the lowest were in Xiamen, Putian, and Ningde. In addition, this paper selected six influencing variables, the research and development intensity, the proportion of agricultural labor force, the added value of agriculture, the agricultural industrial structure, the per capita disposable income of rural residents, and per capita arable land area, to clarify further the impacts on agricultural carbon emissions. Finally, geographically- and temporally-weighted regression (GTWR) was used to measure the direction and degree of the influences of factors on agricultural carbon emission. The conclusion showed that the regression coefficients of each selected factor in cities were positive or negative, which indicated that the impacts on agricultural carbon emission had the characteristics of geospatial nonstationarity.

Deteriorating air quality is one of the most important environmental factors posing significant health risks to urban dwellers. Therefore, an exploration of the factors influencing air pollution and the formulation of targeted policies to address this issue are critically needed. Although many studies have used semi-parametric geographically weighted regression and geographically weighted regression to study the spatial heterogeneity characteristics of influencing factors of PM2.5 concentration change, due to the fixed bandwidth of these methods and other reasons, those studies still lack the ability to describe and explain cross-scale dynamics. The multi-scale geographically weighted regression (MGWR) method allows different variables to have different bandwidths, which can produce more realistic and useful spatial process models. By applying the MGWR method, this study investigated the spatial heterogeneity and spatial scales of impact of factors influencing PM2.5 concentrations in major Chinese cities during the period 2005–2015. This study showed the following: (1) Factors influencing changes in PM2.5 concentrations, such as technology, foreign investment levels, wind speed, precipitation, and Normalized Difference Vegetation Index (NDVI), evidenced significant spatial heterogeneity. Of these factors, precipitation, NDVI, and wind speed had small-scale regional effects, whose bandwidth ratios are all less than 20%, while foreign investment levels and technologies had medium-scale regional effects, whose bandwidth levels are 23% and 32%, respectively. Population, urbanization rates, and industrial structure demonstrated weak spatial heterogeneity, and the scale of their influence was predominantly global. (2) Overall, the change of NDVI was the most influential factor, which can explain 15.3% of the PM2.5 concentration change. Therefore, an enhanced protection of urban surface vegetation would be of universal significance. In some typical areas, dominant factors influencing pollution were evidently heterogeneous. Change in wind speed is a major factor that can explain 51.6% of the change in PM2.5 concentration in cities in the Central Plains, and change in foreign investment levels is the dominant influencing factor in cities in the Yunnan-Guizhou Plateau and the Sichuan Basin, explaining 30.6% and 44.2% of the PM2.5 concentration change, respectively. In cities located within the lower reaches of the Yangtze River, NDVI is a key factor, reducing PM2.5 concentrations by 9.7%. Those results can facilitate the development of region-specific measures and tailored urban policies to reduce PM2.5 pollution levels in different regions such as Northeast China and the Sichuan Basin.

Marginal farm land is land characterised by low food, feed and fodder crop productivity due to soil and environmental limitations. Such land may however be utilised for bio-energy crop production. We investigate the economic viability of small scale combined heat and power anaerobic digestion (CHP AD) projects based on feedstock from farm waste and bio-energy crops grown on a representative temperate latitude marginal farm land in the UK. Using a realistic set of five project feedstock-mix scenarios, and considering standard technology and current market and policy regimes, we deploy a stochastic framework to assess prices of electricity required for these projects to break-even and conduct sensitivity analyses of key project parameters. Accounting for the current market prices and policy tariffs for heat, we find that critical electricity sale prices of about 17.46 p/kWh to 27.12 p/kWh are needed for the projects to break even. These prices are well above the current combined feed-in-tariff support and market prices for electricity over the past years in the UK. We conclude that the use of marginal land to generate power for export using small-scale CHP AD in the UK and the wider temperate latitude countries is unviable, if energy and farming policy regimes do not provide substantial support.