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Recreational ecosystem services (RESs) are the subset of ecosystem services (ESs) that contribute to human society through recreation, recreation opportunities, and experiences. Existing RESs mostly focus on a single recreational landscape; alternatively, when mapping RESs, multiple types of landscapes are often drawn together, ignoring the differences in recreational landscape (RL) types and affecting the accuracy of the mapping. At the same time, quantifying the monetary value of RESs has been a challenge due to the lack of market substitutes that can approximate the prices associated with these non-excludable goods. This study used the MaxENT model, then classified and used recreational resource POI data, combined with environmental data on the existence or generation of different types of RL, mapped RES from the perspective of RL supply, and conducted monetization and evaluations of RL. The results show that the models' AUC values are all greater than 0.7, and the distribution of RL supply can be drawn relatively accurately. The Qinghai–Tibet Plateau National Park Group (QTPNPG) has the largest high-quality geomorphic recreational landscape (69,081.02 km2), followed by a high-quality biological recreational landscape (59,348.65 km2) and a high-quality hydrological recreational landscape (33,251.20 km2). The national parks in the eastern part of the Qinghai–Tibet Plateau have a larger proportion of high-value areas of the RES. The total monetary value of the RES is CNY 8.323 billion, and the average monetary value of RES per unit area is CNY 20,200/km2. Our study optimizes the method of mapping RESs and provides a new way of quantifying the monetary value of RESs. The results can provide a reference for the recreational development of THE QTPNPG and its contribution to regional sustainable development. [ABSTRACT FROM AUTHOR]

The vertical transition zone of mountain vegetation is characterized by high species diversity, and the width of the transition zone may serve as an indirect indicator of climate change. However, research into the differential characteristics of vegetation response to climate changes at the boundary of vertical transition zones has been limited. This study employs MODIS and climate data spanning 2001 to 2018 to investigate spatiotemporal trends in precipitation (PRE), temperature (TMP), radiation (RAD), and Normalized Difference Vegetation Index (NDVI) across nine montane deciduous broad-leaved forests in the eastern monsoon region of China. It explores the time-lag and -accumulation effects of climatic variables on NDVI, quantifying their relative contributions to both its short-term and interannual variations. Results show that, notably, with the Qinling-Daba Mountains as a demarcation, northern regions exhibit significant increases in RAD (0.874–2.047 W m−2/a), whereas southern regions demonstrate notable rises in TMP (0.59–0.73 °C/10a). Areas of lower annual PRE correspond to the most rapid increases in annual average NDVI (5.045 × 10−3/a). NDVI's lag time and cumulative duration responses to TMP are the shortest (0 and 2~4 periods), while its correlation with RAD is the strongest (0.815–0.975), generally decreasing from higher to lower latitudes. TMP significantly affects NDVI variations, impacting both short-term and interannual trends, with PRE driving short-term fluctuations and RAD dictating long-term shifts. This research provides critical data and a theoretical framework that enhances our understanding of how regional vegetation's vertical zonation responds to climate change, thereby making a substantial contribution to the study of mountain vegetation's diverse adaptability to climatic variations. [ABSTRACT FROM AUTHOR]

Simple Summary: We constructed a high-quality genome assembly of Eupleurogrammus muticus at the chromosomal level using PacBio SMRT, Illumina Nova-Seq, and Hi-C technologies. By combining genomic annotation, comparative genomic analyses, and species attribute information, we identified many candidate genes related to the whip-like tail, innate immunity, and DNA repair of E. muticus, and determined the evolutionary relationship and divergence time between E. muticus and related species. These findings provide important genomic resources for exploring the genetic mechanisms underlying the unique characteristics of E. muticus and fishery resource conservation. Smallhead hairtail (Eupleurogrammus muticus) is an important marine economic fish distributed along the northern Indian Ocean and the northwest Pacific coast; however, little is known about the mechanism of its genetic evolution. This study generated the first genome assembly of E. muticus at the chromosomal level using a combination of PacBio SMRT, Illumina Nova-Seq, and Hi-C technologies. The final assembled genome size was 709.27 Mb, with a contig N50 of 25.07 Mb, GC content of 40.81%, heterozygosity rate of 1.18%, and repetitive sequence rate of 35.43%. E. muticus genome contained 21,949 protein-coding genes (97.92% of the genes were functionally annotated) and 24 chromosomes. There were 143 expansion gene families, 708 contraction gene families, and 4888 positively selected genes in the genome. Based on the comparative genomic analyses, we screened several candidate genes and pathways related to whip-like tail formation, innate immunity, and DNA repair in E. muticus. These findings preliminarily reveal some molecular evolutionary mechanisms of E. muticus at the genomic level and provide important reference genomic data for the genetic studies of other trichiurids. [ABSTRACT FROM AUTHOR]

This manuscript presents an analysis and optimization scheme for the ultra-wideband passive reconfigurable polyphase filters (PPFs) to minimize I/Q (in-phase and quadrature-phase) phase/amplitude mismatch and voltage loss. By building a mathematical model of the voltage transfer, the relationship between the resonant frequency of each stage and the I/Q mismatch and the relationship between the network impedance and the voltage loss are revealed, providing a scheme for PPF optimization. The proof-of-concept 2~8 GHz wideband reconfigurable PPF is designed in a 55 nm CMOS process. The optimization scheme enables the designed PPF to achieve an I/Q phase mismatch within 0.2439° and an I/Q amplitude mismatch within 0.098 dB throughout the entire band, and it shows great robustness during Monte Carlo sampling. The maximum voltage loss is 17.7 dB, and the total chip area is 0.174 × 0.145 mm2. [ABSTRACT FROM AUTHOR]

In Kibira National Park, Burundi, socioeconomic and demographic factors lead to environmental performance challenges that impede biodiversity; thus, understanding the impact of these determinants on land use and land cover change is important to address these challenges. In this study, a multivariate analysis of variance (MANOVA) model was used to quantify the impact of socioeconomic and demographic factors on land cover/land use (LCLU) changes using Landsat images captured between 1990 and 2021. In addition, the impact of the environmental performance index (EPI), particularly ecosystem vitality (ECO), on landscape fragmentation was examined using a Spearman correlation analysis. A Pearson correlation analysis and a principal component analysis (PCA) were used to investigate the connections between the indicators of relevance in this study. The results reveal a decrease in forestland from 86.1% to 81.32%, a decrease in water bodies from 0.352% to 0.178%, and a decrease in open land from 2.124% to 1.134%, whereas grassland increased from 11.43% to 17.37% between 1990 and 2021. The landscape fragmentation in the edge density, contagion (CONTAG), largest patch index (LPI), number of patches (NP), and patch density (PD) was reduced in 2011 but increased again from 2016 to 2021, when only the ED fragmentation continued to decrease. The MANOVA results show that the rural population had a significant impact on LCLU changes at the 5% level of significance. Demographic factors significantly contributed to changes in grassland and forestland at a probability of 5%. In addition, moderately significant connections were observed between population growth per year and water and between gross domestic product (GDP) and grassland at the 10% level. ECO issues in ecosystem services (ECSs) were statistically significant for the increased fragmentation metrics, while biodiversity and habitat (BDH) were important for reducing the edge density (ED) at a 5% level of significance. The Pearson correlations showed a substantial positive relationship between the socioeconomic and demographic components, whereas a negative connection was found between the forestland and BDH indicators. These findings are essential for understanding the significant drivers of LCLU changes and the influence of environmental performance on the landscape pattern. [ABSTRACT FROM AUTHOR]