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Achieving carbon neutrality through increasing carbon sinks is a crucial strategy for reaching long-term climate objectives. During rapid urbanization, the degradation of vegetation structure and quantity in fragmented patches leads to the reduction of the carbon sink capacity. Establishing the well-design ecological spatial network is crucial for improving the carbon sink capacity. This study focuses on enhancing the carbon sink capacity in the Wuhan Metropolitan Area (WMA) through a four-step approach–identification, construction, assessment, and optimization–to improve the ecological spatial structure of carbon sink patches and increase carbon sink capacity. The results show that we initially built 27 carbon sink patches and 52 networks, prioritizing 15 core networks. Due to the low connectivity between the Western and other regions, we added 18 steppingstones and 12 networks to enhance overall connectivity and stability of spatial network. Verification shows that our scheme benefits the connectivity and stability of whole ecological network of WMA, and increases the total carbon sink by 11.17 Mt CO2. This research enriches methods for increasing carbon sinks in urban areas and provides theoretical support for achieving carbon neutrality.

Improving the attractiveness of urban waterfronts has become an important objective to promote economic development and improve the environmental quality. However, few studies have focused on the inherent characteristics of urban waterfront attractiveness. In this study, mobile phone signaling data and the TOPSIS (Technique for Order Preference by Similarity to an Ideal Solution) were used to construct the attractiveness evaluation system of the riverside in Wuhan. The OLS (ordinary least squares) regression model was used to analyze the relationship between the POI (point of interest) and the attractiveness of river waterfronts. Furthermore, the high-or-low-value aggregation classification of research units was performed according to attractiveness and the POI indicators to reveal the influencing factors of the attractiveness of the Wuhan urban riverside. Results showed the following. (1) The high-value distribution of attractiveness of the river waterfronts in Wuhan presented regional aggregation characteristics, and the attractiveness of economically developed areas was high. (2) Consumer POIs (CPOIs) and outdoor recreation POIs (RPOIs) had a positive effect on the attractiveness of the riverside in Wuhan, while housing POIs (HPOIs), public service POIs (OPOIs), and the high degree of POI mixing had a negative impact on the attractiveness of the urban riverside. (3) The high–high agglomeration spaces were mainly concentrated in the economically developed areas of the city center, which are mainly open spaces where urban cultural activities are held, while the low–low agglomeration spaces were mostly gathered in the suburban areas. The spatial distribution of the high–low agglomeration spaces, which are mainly green open spaces, was relatively fragmented, while the low–high agglomeration spaces, which are mainly freight terminals, linear walks, and residential areas, were near the city center.

A regioselective carbosilylation of alkenes is a powerful strategy to access functionalized silylated alkanes. In this study, the authors report a catalyst-free carbosilylation of alkenes using silyl boronates and organic fluorides, mediated by t BuOK, and synthesise various silylated alkanes with tertiary or quaternary carbon centres.

Summary: We disclose the Cu-catalyzed enantioselective synthesis of 3-methyl-3-propargyl-indolines, which contain a quaternary stereogenic carbon center, via the decarboxylative [4 + 1] annulation of 4-methyl-4-propargyl-benzoxazinanones with variety of sulfur ylides. The reaction proceeds predominantly through a γ-attack at the Cu-allenylidene intermediates by sulfur ylides to provide the corresponding indolines in good yield and high enantioselectivity (up to 91% ee). In contrast, the reaction of 4-trifluoromethyl-4-propargyl-benzoxazinanones with sulfur ylides delivers 3-trifluoromethyl-2-functionalized indoles in good to high yield via an unexpected α-attack at the Cu-allenylidene intermediates. Control over the α/γ-attack at the Cu-allenylidene intermediates by the same interceptors was achieved for the first time by the use of trifluoromethyl substituents. : Organic Chemistry; Organic Synthesis; Physical Organic Chemistry Subject Areas: Organic Chemistry, Organic Synthesis, Physical Organic Chemistry