Predicting suitable habitat for the endangered tree Ormosia microphylla in China.

Climate change has significantly influenced the growth and distribution of plant species, particularly those with a narrow ecological niche. Understanding climate change impacts on the distribution and spatial pattern of endangered species can improve conservation strategies. The MaxEnt model is widely applied to predict species distribution and environmental tolerance based on occurrence data. This study investigated the suitable habitats of the endangered Ormosia microphylla in China and evaluated the importance of bioclimatic factors in shaping its distribution. Occurrence data and environmental variables were gleaned to construct the MaxEnt model, and the resulting suitable habitat maps were evaluated for accuracy. The results showed that the MaxEnt model had an excellent simulation quality (AUC = 0.962). The major environmental factors predicting the current distribution of O. microphylla were the mean diurnal range (bio2) and precipitation of the driest month (bio14). The current core potential distribution areas were concentrated in Guangxi, Fujian, Guizhou, Guangdong, and Hunan provinces in south China, demonstrating significant differences in their distribution areas. Our findings contribute to developing effective conservation and management measures for O. microphylla, addressing the critical need for reliable prediction of unfavorable impacts on the potential suitable habitats of the endangered species.

Distribution pattern of large old Ginkgo biloba in China under climate change scenarios.

Large old Ginkgo biloba trees (LOGTs), with profound ecological and cultural significance in China, face increasing threats from climate change and human activities. We employed the BIOCLIM and DOMAIN species distribution models to predict their spatial patterns under the present climate and doubled-CO2 climate change scenario in 2100. We collected 604 validated LOGT occurrence records and data on 19 bioclimate factors for the analysis. Our study yielded a LOGT geographic distribution pattern covering a wide latitudinal belt extending from south subtropical to temperate zones in central and eastern China, concentrating in low elevations and coastal regions. The principal component analysis identified the dominant bioclimatic factors shaping their distribution, namely annual precipitation and low winter temperatures. BIOCLIM and DOMAIN generated predicted suitable habitats that match the present distribution range well. However, under the future climate scenario, the models indicated habitat retentions mainly in the core distribution areas and habitat losses mainly in the southern edge of the present range and scattered pockets elsewhere. Some retained habitats, including excellent ones, will suffer from fragmentation. The predicted new habitats may permit some range expansion and migration but are beset by small patch size and large interpatch distance, bringing fragmentation and gene flow restrictions. The anticipated projected range decline highlights considerable threats climate change poses to the long-term survival of the precious natural-cum-cultural resource. Understanding the distribution patterns and underlying drivers and distillation of practical conservation measures can foster sustainable management vis-a-vis the looming global change.

Effects of climate-change scenarios on the distribution patterns of Castanea henryi.

Castanea henryi, with edible nuts and timber value, is a key tree species playing essential roles in China's subtropical forest ecosystems. However, natural and human perturbations have nearly depleted its wild populations. The study identified the dominant environmental variables enabling and limiting its distribution and predicted its suitable habitats and distribution. The 212 occurrence records covering the whole distribution range of C. henryi in China and nine main bioclimatic variables were selected for detailed analysis. We applied the maximum entropy model (MaxEnt) and QGIS to predict potentially suitable habitats under the current and four future climate-change scenarios. The limiting factors for distribution were accessed by Jackknife, percent contribution, and permutation importance. We found that the current distribution areas were concentrated in the typical subtropical zone, mainly Central and South China provinces. The modeling results indicated temperature as the critical determinant of distribution patterns, including mean temperature of the coldest quarter, isothermality, and mean diurnal range. Winter low temperature imposed an effective constraint on its spread. Moisture served as a secondary factor in species distribution, involving precipitation seasonality and annual precipitation. Under future climate-change scenarios, excellent habitats would expand and shift northwards, whereas range contraction would occur on the southern edge. Extreme climate change could bring notable range shrinkage. This study provided a basis for protecting the species' germplasm resources. The findings could guide the management, cultivation, and conservation of C. henryi, assisted by a proposed three-domain operation framework: preservation areas, loss areas, and new areas, each to be implemented using tailor-made strategies.

Environmental Factors Driving the Spatial Distribution Pattern of Venerable Trees in Sichuan Province, China.

Venerable trees are important natural resources and cultural heritage, offering historical, ecological, social and economic value. However, global warming and anthropogenic activities have threatened their welfare and survival. A comprehensive understanding of their current and future spatial patterns, vis-á-vis environmental conditions, can inform the co-management of sustainable resource use and conservation. We employed the existing spatial occurrence data and environmental variables (bioclimate and elevation) to simulate the optimal habitats for venerable trees in China's Sichuan Province. We evaluated the current and future climate scenarios of 2100 with double CO2 concentration. The BIOCLIM and QGIS spatial analyses assessed the primary factors of geographical distribution. The results identified 10,720 venerable trees from 123 species, 81 genera and 42 families. Cupressus funebris dominated, with the maximum importance value, followed by Ginkgo biloba, Ficus virens var. sublanceolata, and Phoebe zhennan. The elevation distribution of tree abundance and species richness demonstrated a unimodal pattern, skewing to the low-elevation end, with a concentration in the 600-1500 m low-medium altitude. The majority of trees and excellent habitats were found in eastern Sichuan with a less harsh terrain and climate. The bio3 (isothermality) and bio7 (temperature annual range) factors significantly influenced tree occurrence. Temperature imposed a greater effect on distribution than moisture under the current climate scenario. For the future climate-change scenario, the suitable habitats were predicted to maintain an overall stable pattern, with largely contiguous expansions of better habitats. However, climate warming would shrink the excellent habitats on the plains. The findings can inform strategies and guidelines for venerable-tree conservation in Sichuan. Furthermore, vulnerable areas could be identified. The future range expansion sites could be enlisted to cultivate new trees to replenish the venerable-tree pool. Habitat patches that remain sustainable could provide refugia with the potential for protected-area designation.

Measuring environmental efficiency and technology inequality of China's power sector: methodological comparisons among data envelopment analysis, free disposable hull, and super free disposable hull models.

China's power sector has received great research attention because of its large energy consumption and CO2 emissions. This study assesses the environmental efficiency and technology inequality of China's power sector from 2008 to 2017. Methodologically, this study proposes a non-radial FDH (free disposable hull) model and a super non-radial FDH model. The non-radial FDH model relaxes the convex assumption and captures all inefficiencies of inputs, desirable output and undesirable output. The super non-radial model is capable of discriminating efficient power sectors and always has feasible solutions. We also compare their performance with the non-radial data envelopment analysis (DEA) model. The main conclusions are summarized as follows: First, the environmental efficiency of China's power sector has experienced steady growth; the power sectors in the east region outperform those in other regions. Second, the proposed FDH models are more applicable and reliable than the non-radial DEA model in efficiency measurement of China's power sector, due to the indivisibility of labor. Third, there has been growing technology inequality and the main driving factor determining technology inequality is the inter-region efficiency Gini coefficient. To improve environmental efficiency and eliminate technology inequality, the government should mainly solve the issue of excessive labor input and establish a free technology market for technology trading.

Mitochondrial genome of the critically endangered Baer's Pochard, Aythya baeri, and its phylogenetic relationship with other Anatidae species.

Historically, the diving duck, Baer's Pochard (Aythya baeri) was widely distributed in East and South Asia, but according to a recent estimate, its global population is now less than 1000 individuals. To date, the mitochondrial genome of A. baeri has not been deposited and is not available in GenBank. Therefore, we aimed to sequence the complete mitochondrial genome of this species. The genome was 16,623 bp in length, double stranded, circular in shape, and contained 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and one non-coding control region. Many structural and compositional similarities were discovered between A. baeri and the other three Aythya mitochondrial genomes. Among 13 protein-coding genes of the four Aythya species, the fastest-evolving gene was ATP8 while the slowest-evolving gene was COII. Furthermore, the phylogenetic tree of Anatidae based on Bayesian inference and maximum likelihood methods showed that the relationships among 15 genera of the Anatidae family were as follows: Dendrocygna was an early diverging lineage that was fairly distant from the other ingroup taxa; Cygnus, Branta, and Anser were clustered into one branch that corresponded to the Anserinae subfamily; and Aythya, Asarcornis, Netta, Anas, Mareca, Mergus, Lophodytes, Bucephala, Tadorna, Cairina, and Aix were clustered into another branch that corresponded to the Anatinae subfamily. Our target species and three other Aythya species formed a monophyletic group. These results provide new mitogenomic information to support further phylogenetic and taxonomic studies and genetic conservation of Anatidae species.

Complete mitochondrial genome sequence of the northern red-shouldered macaw (Diopsittaca nobilis).

The northern red-shouldered macaw, Diopsittaca nobilis, is listed in the Convention on International Trade in Endangered Species of Wild Fauna and Flora Appendix II. Here, we report for the first time the complete mitochondrial genome of D. nobilis. This new sequence is 16,992 base pairs (bp) in length and includes 13 protein-coding genes, 22 transfer RNAs, two ribosomal RNAs, and a single non-coding control region. The overall nucleotide composition of this sequence consists of 30.40% A, 14.00% G, 23.60% T, and 32.00% C. The phylogenetic relationships suggested that the mitogenome of D. nobilis is close to that of three other macaw species. Our results provide useful mitogenomic information to support further studies on the phylogeny and taxonomy of Psittaciformes.

Towards carbon neutrality and China's 14th Five-Year Plan: Clean energy transition, sustainable urban development, and investment priorities.

China's 14th Five-Year Plan, for the period 2021-25, presents a real opportunity for China to link its long-term climate goals with its short-to medium-term social and economic development plans. China's recent commitment to achieving carbon neutrality by 2060 has set a clear direction for its economy, but requires ratcheting up ambition on its near-term climate policy. Against this background, this paper discusses major action areas for China's 14th Five-Year Plan after COVID-19, especially focusing on three aspects: the energy transition, a new type of sustainable urban development, and investment priorities. China's role in the world is now of a magnitude that makes its actions in the immediate future critical to how the world goes forward. This decade, 2021-2030, is of fundamental importance to human history. If society locks in dirty and high-carbon capital, it raises profound risks of irreversible damage to the world's climate. It is crucial for China to peak its emissions in the 14th Five-Year Plan (by 2025), making the transition earlier and cheaper, enhancing its international competitiveness in growing new markets and setting a strong example for the world. The benefits for China and the world as a whole could be immense.

Characterization and phylogenetic analysis of the complete Green-winged macaw (Ara chloropterus) mitogenome.

In this study, we sequenced and characterized the complete mitochondrial genome of Green-winged macaw (Ara chloropterus) listed on CITES Appendix II. The circular double-stranded genome was 16,991 bp in size and included 22 transfer RNA (tRNA) genes, 13 protein-coding genes (PCGs), two ribosomal RNA genes (rrnL and rrnS), and one non-coding control region (D-loop). Both order and arrangement of genes were identical to those of other animal mitogenomes. The base content was 30.00% A, 14.38% G, 23.27% T, and 32.35% C, with an A + T content of 53.37%. Furthermore, phylogenetic analysis indicated that A. chloropterus is closely related to the Blue and yellow macaw (A. ararauna).

The complete chloroplast genome sequence of Quercus phillyraeoides (Fagaceae).

Quercus phillyraeoides A. Gray is an evergreen oak species native to East Asia, and it plays a vital role in mountain ecosystems. In this study, we assembled the complete chloroplast genome of Q. phillyraeoides based on sequencing data. The genome was circular and 161,384 bp in length, consisting of a large single-copy region (90,617 bp), small single-copy region (19,035 bp), and two short inverted repeat regions (25,866 bp). We found that the cp genome encodes for 131 genes, including 85 protein-coding genes (PCGs), 8 rRNA genes, and 37 tRNA genes. The results of the phylogenetic analysis of the complete cp genome sequence illustrated that Q. phillyraeoides is a member of the section Quercus and it is most closely related to Q. tarokoensis.

3,5-Di-tert-butyl-3'-(N-tert-butyl-N-aminoxy)-4-oxybiphenyl: A Heterospin Diradical with Temperature Dependent Behavior.

The title diradical was synthesized and investigated by ESR and UV-vis spectroscopy. It was found to have a lifetime of weeks even in the presence of oxygen, and even survives brief heating in toluene up to about 60 °C. In the UV-vis spectrum, the diradical showed reversible thermochromic behavior in the -10 to 50 °C range. In the ESR spectrum, hyperfine analysis showed nearly isolated behavior by the phenoxyl and nitroxide spin carrying units. Upon warming, additional, broad lines appeared at the expense of the lower temperature lines. This temperature behavior was reversible over the 0 to 50 °C range, so long as the raised temperatures were not maintained for long time periods. The spectral behavior is interpreted as being due to temperature-dependent conformational effects on the exchange coupling between the spin carrying units, i.e., J-modulated exchange behavior.