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Quantitative evaluation of ecological restoration effectiveness is critical to provide operational feedback for mine restoration and to implement adaptive management. Existing practice are limited by a focus on single elements and sub-project scales. This paper proposed an ecological restoration evaluation framework with 8 dimensions and 24 indicators from macro perspective, taking a mineral concentration area (MCA) in southeastern Hubei as a case study. LandTrendr and random forest algorithms were used to extract and classify different ecological disturbances around the mine sites from micro perspective. The ecological restoration process and disturbances were revealed at different scales. The findings demonstrated that the total ecological restoration area increased by 10.092% from 2010 to 2019, showing an improving trend, but it has not recovered to the ecological level of 2000. The ecologically degraded areas were shifting to the urban areas with concentrated population and around the water, from area diffusion to strip extension. Ecological disturbances changes in mining areas shows there was a trend towards slower ecological restoration of mine sites after 2019. Disturbances due to construction development occurred in areas surrounding closed mining areas, especially in Huangshi National Mine Park and Tonglvshan Copper Mine. Notably, natural restoration occurred in mine-forest compound area without any ecological restoration measures. While the findings demonstrate the effectiveness of ecological engineering, there are still some limitations in the mine ecological restoration process. In response, we suggest an international framework for ecological restoration in mining areas to solve the cognitive gaps in ecological engineering, improve the management of the whole process of ecological restoration, and optimize the ecological restoration effect in mining areas. [Display omitted] • An ecological restoration assessment framework at macro perspective was proposed. • Different disturbance and recovery types in 3-km buffer were analyzed. • The ecological disturbance and restoration characteristics were analyzed in different typical mining areas. [ABSTRACT FROM AUTHOR]

Nitrogen fertilizer and planting density are two crucial factors that affect the yield of common buckwheat ( Fagopyrum esculentum M.). Youqiao2, a common buckwheat cultivar with high photosynthetic capacity and planted widely in local production was used to investigate the effects of nitrogen fertilizer and planting density on the leaf photosynthetic characteristics, agronomic traits, and grain yield in common buckwheat by a split plot design. The main plots were assigned to three nitrogen fertilizer rates: 0, 45, and 90 kg ha −1 , and the subplots were assigned to three planting densities: 60, 90, and 120 plants m −2 . Results showed that the grain yield was significantly and positively correlated with net photosynthesis rate (P n ), stomatal conductance (G s ), transpiration rate (T r ), stomatal limitation value (L s ), chlorophyll content (SPAD value), leaf area index (LAI), plant height, stem diameter, branch number, internode number, grain number per plant, and 1000-grain weight, while significantly and negatively correlated with intercellular CO 2 concentration (C i ) and water-use efficiency (WUE). The P n , G s , T r , L s , SPAD, LAI, grain yield, stem diameter, branch number, internode number, grain number per plant, and 1000-grain weight increased and then decreased with the increase of nitrogen fertilizer and planting density, and their maximum values appeared in the nitrogen fertilization of 45 kg ha −1 and planting density of 90 plants m −2 treatment. The C i and WUE decreased and then increased with the increase of nitrogen fertilizer and planting density, and their minimum values appeared in the nitrogen fertilization of 45 kg ha −1 and planting density of 90 plants m −2 treatment. The plant height increased with the increase of nitrogen fertilizer, while decreased with the increase of planting density. These results suggested that nitrogen fertilizer and planting density had significant effects on the leaf photosynthetic capacity, agronomic traits, and grain yield of common buckwheat, and the combination of nitrogen fertilization of 45 kg ha −1 and planting density of 90 plants m −2 is recommended for common buckwheat planting. [ABSTRACT FROM AUTHOR]

[Display omitted] • A hydrothermal co-assembling strategy is employed to synthesize an assembly catalyst. • N-doped holey graphene (NHG) anchored Pd nanoparticles (Pd NP) is assembled with fibrous aluminum silicate (ASFs) agglomerate. • The Pd NP /NHG-ASFs catalyst integrated to a fixed-bed system allows continuous-flow reduction of nitroarenes. • The fixed-bed system based on Pd NP /NHG-ASFs catalyst displays a high processing rate. Rational design and preparation of efficient fixed-bed catalysts for continuous-flow system are highly desired but remain daunting challenges. Herein, we report the synthesis of an assembly catalyst consisted of aluminium silicate fibers (ASFs) agglomerate and Pd nanoparticles (Pd NP) decorated N-doped holey graphene (NHG) through a facile hydrothermal co-assembling strategy. Due to the interconnect network and porous structure, the as-obtained Pd NP /NHG-ASFs assembly is suitable to be utilized as a fixed-bed catalyst for organic reactions in continuous-flow mode. The processing rate is much higher than that of the previously reported fixed-bed systems based on metal-based catalysts. In addition, the catalytic continuous-flow system displays a remarkable durability and good substrate generality to other substituted nitrobenzenes. This work provides rational design concept for efficient fixed-bed catalyst with dual active components and paves a way for the industrial application in organic synthesis. [ABSTRACT FROM AUTHOR]