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In the context of rapid urbanization, urban population differentiation has become increasingly pronounced. Regional development strategies based on growth scenarios often lead to continuous expansion, regardless of urban population status. Such "one-size-fits-all" models exacerbate resource waste and negatively impact urban land use efficiency (ULUE). This study aims to explore the mechanisms by which urban population growth and shrinkage (UPGS) affect ULUE, with the goal of enhancing ULUE and promoting sustainable urban development. We analyzed 34 prefecture-level cities in China's three northeastern provinces. First, we identified UPGS using population data. We then employed a three-stage SBM-DEA model to measure ULUE from 2000 to 2020. Spatial analysis methods were used to examine the spatiotemporal characteristics and correlations between UPGS and ULUE. Additionally, mediating effect models and spatial Durbin models were utilized to empirically test the impact processes, mechanisms, and spatial heterogeneity. Our findings reveal that: (1) Over the past 20 years, urban population shrinkage in northeastern China has intensified, and significant regional disparities in urban development are evident. (2) Population growth positively influences ULUE, while population shrinkage inhibits its improvement. (3) Economic development, technological innovation, and industrial structure upgrading are key factors in enhancing ULUE in this region, while the impact of public services on ULUE varies significantly at different stages of urban development. (4) Economic development, technological innovation, and industrial structure upgrading exhibit spatial spillover effects, whereas public services are constrained by regional limitations, resulting in minimal spatial spillover effects. To foster coordinated regional development, this study proposes policy recommendations, including strengthening support for resource-dependent cities, optimizing the allocation of public resources, and promoting technological innovation and industrial diversification. [ABSTRACT FROM AUTHOR]

With the rapid social and economic development of the Taihu region, Taihu Lake now faces an increasingly severe eutrophication problem. Pollution from surrounding catchments contributes greatly to the eutrophication of water bodies in the region. Investigation of surface flow and associated mass transport for the Xitiaoxi catchment is of a significant degree of importance as the Xitiaoxi catchment is one of the major catchments within the Taihu region. A SWAT-based distributed hydrological model was established for the Xitiaoxi catchment. The model was calibrated and verified using hydrometeorological data from 1988 to 2001. The results indicate that the modeled daily and annual stream flow match the observed data both in the calibration period and the verification period, with a linear regression coefficient R2 and a coefficient e for modeled daily stream flow greater than 0.8 at Hengtangcun and Fanjiacun gauge stations. The results show that the runoff process in the Xitiaoxi catchment is affected both by rainfall and human activities (e.g., reservoirs and polder areas). Moreover, the human activities weaken flood peaks more noticeably during rainstorms. The water balance analysis reveals the percentages of precipitation made up by surface flow, evapotranspiration, groundwater recharge and the change of soil storage, all of which are considered useful to the further understanding of the hydrological processes in the Xitiaoxi catchment. This study provides a good base for further studies in mass transport modeling and comparison of modeling results from similar hydrological models.

The order Boletales is a group of fungi with complex life styles, which include saprophytic and ectomycorrhizal mushroom-forming fungi. In the present study, the complete mitogenomes of two saprophytic Boletales species, Coniophora olivacea , and C. puteana , were assembled and compared with mitogenomes of ectomycorrhizal Boletales. Both mitogenomes comprised circular DNA molecules with sizes of 78,350 bp and 79,655 bp, respectively. Comparative mitogenomic analysis indicated that the two saprophytic Boletales species contained more plasmid-derived (7 on average) and unknown functional genes (12 on average) than the four ectomycorrhizal Boletales species previously reported. In addition, the core protein coding genes, nad2 and rps3 , were found to be subjected to positive selection pressure between some Boletales species. Frequent intron gain/loss events were detected in Boletales and Basidiomycetes, and several novel intron classes were found in two Coniophora species. A total of 33 introns were detected in C. olivacea , and most were found to have undergone contraction in the C. olivacea mitogenome. Mitochondrial genes of Coniophora species were found to have undergone large-scale gene rearrangements, and the accumulation of intra-genomic repeats in the mitogenome was considered as one of the main contributing factors. Based on combined mitochondrial gene sets, we obtained a well-supported phylogenetic tree for 76 Basidiomycetes, demonstrating the utility of mitochondrial gene analysis for inferring Basidiomycetes phylogeny. The study served as the first report on the mitogenomes of the family Coniophorineae, which will help to understand the origin and evolution patterns of Boletales species with complex lifestyles., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 The Authors. Published by Elsevier B.V. on behalf of Research Network of Computational and Structural Biotechnology.)