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Ecological control line (ECL) has become an important policy for enhancing ecological conservation and achieving sustainable urban development. Landscape connectivity of ecological network provides a method for exploring the effect of ECL policy on biodiversity conservation. This study used Shenzhen as an example to analyze the distribution of important habitats based on species occurrence points, environmental factors and artificial neural network methods. Four-phase ecological networks of focal species (Ardea cinerea, Callosciurus erythraeus, Copsychus saularis, Egretta garzetta, Pycnonotus sinensis) in 2000, 2010, 2015, and 2020 were constructed, and the effects and changes of ECL on habitat connectivity of species, geographical zone, and species zone scales were sequently analyzed using the difference-in-difference method. The results showed that: (1) Forty-one important habitats were identified, with a total area of 743 km2, and the average area of each habitat was 18.1 km2. The number of ecological corridors and the area of ecological pinch points in Shenzhen decreased in the first ten years but remained stable over the final ten years. (2) ECL delineation can promote habitat connectivity of regional species and with the passage of time, this promoting effect increases. The protective effect in the high habitat quality zone was greater than that in the low habitat quality zone. (3) City managers can develop habitat connectivity conservation schemes for different species according to the five habitat quality zones: high, mid-high, middle, mid-low, and low. This study proposes a method to assess the effectiveness of the existing ecological control line, and provide a scientific basis for formulating, adusting and optimizing ecological management.

Abstract To solve the problems of low gasification efficiency and high tar content caused by solid–solid contact between biomass and oxygen carrier in traditional biomass chemical looping gasification process. The decoupling strategy was adopted to decouple the biomass gasification process, and the composite oxygen carrier was prepared by embedding Fe2O3 in molecular sieve SBA-16 for the chemical looping reforming process of pyrolysis micromolecular model compound methane, which was expected to realize the directional reforming of pyrolysis volatiles to prepare hydrogen-rich syngas. Thermodynamic analysis of the reaction system was carried out based on the Gibbs free energy minimization method, and the reforming performance was evaluated by a fixed bed reactor, and the kinetic parameters were solved based on the gas–solid reaction model. Thermodynamic analysis verified the feasibility of the reaction and provided theoretical guidance for experimental design. The experimental results showed that the reaction performance of Fe2O3@SBA-16 was compared with that of pure Fe2O3 and Fe2O3@SBA-15, and the syngas yield was increased by 55.3% and 20.7% respectively, and it had good cycle stability. Kinetic analysis showed that the kinetic model changed from three-dimensional diffusion to first-order reaction with the increase of temperature. The activation energy was 192.79 kJ/mol by fitting. This paper provides basic data for the directional preparation of hydrogen-rich syngas from biomass and the design of oxygen carriers for pyrolysis of all-component chemical looping reforming.