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Davidia involucrata Baill. is a rare and endangered plant species that exhibits high sensitivity to environmental stressors. High-light stress significantly impedes its growth and development. However, the molecular mechanisms underlying Davidia involucrata Baill. ’s response to high-light stress remain poorly understood. In this study, transcriptome sequencing and bioinformatics analyses were employed to systematically investigate the response of Davidia involucrata Baill. to high-light stress under varying soil moisture and air humidity conditions. The results revealed that under different soil moisture conditions, Davidia involucrata Baill. significantly activated pathways related to reactive oxygen species and heat stress responses in reaction to high-light stress. However, notable differences were observed in the extent of pathway activation: under moist soil conditions, Davidia involucrata Baill. primarily responded to high-light stress via reactive oxygen species-related pathways, whereas under dry soil conditions, it predominantly relied on heat stress response pathways. Furthermore, under non-humidified air conditions, Davidia involucrata Baill. responded to high-light stress and combined stress by activating the MAPK signaling pathway and indole-containing compound biosynthetic process, respectively. We also found that when high-light stress and drought stress occur simultaneously, Davidia involucrata Baill. prioritizes mitigating the damage caused by high-light stress. In summary, this study elucidated the key molecular mechanisms underlying Davidia involucrata Baill. ’s response to high-light stress, providing a theoretical foundation for the conservation of rare plant species, enhancement of environmental adaptability, and development of stress-resistant cultivation strategies.

The Yulong Snow Mountain (YSM) is a region of temperate glaciers in the southeast Qinghai-Tibetan Plateau. The present study systematically assessed the glacier changes during the past several decades using ground-based and remotely sensed observations and referencing topographic maps. The images and maps revealed that the glaciers area in the YSM retreated by 64.02% from 1957 to 2017. The length of Baishui River Glacier No. 1 decreased by 12.5 m/year during this period, whereas the front elevation of this glacier increased by 10.83 m/year. The mean annual mass balance of this glacier was at − 0.42 metre water equivalent from 1957 to 2017, and its accumulative mass balance was − 27.45 metre water equivalent. The glacier retreats of glacier area, glacier front, and mass balance in the YSM primarily resulted from the increasing air temperature. These glacier retreats not only will have a negative impact on glacier tourism in the future, e.g., the retreat or disappearance of glaciers will reduce the attractiveness of mountainous scenic spots, but also will create new opportunities for the development of local tourism, e.g., “last chance” will simulate tourists’ curiosity. Hence, the findings of our present study help to understand the mechanism between accelerated ablation of temperate glaciers and climate change in southeast regions of Qinghai-Tibetan Plateau and provide references for local tourism administrations.

Davidia involucrata Baill. is a species that thrives in warm, humid climates with consistently moist soil conditions. With rising global temperatures and an increasing frequency of droughts, the natural habitat of Davidia involucrata Baill. is facing severe threats. In‐depth investigation of the molecular mechanisms underlying Davidia involucrata Baill.'s response to drought stress is crucial for the conservation of this rare species and the enhancement of its environmental adaptability. This study systematically analyzed the drought stress response of Davidia involucrata Baill. under varying light conditions through transcriptome data analysis. The results showed that under different light conditions, Davidia involucrata Baill. responded to drought stress by regulating its internal osmotic balance via the “response to mannitol” pathway. Notably, the molecular mechanisms by which Davidia involucrata Baill. responds to drought stress vary significantly under different light conditions. Compared with high light intensity, Davidia involucrata Baill. under shaded conditions responded to drought stress by upregulating glycosyltransferase‐related pathways. In addition, three soil drought–related pathway genes (SDRPGs) (Dinv08247, Dinv34952, and Dinv00865) involved in the regulation of drought stress in Davidia involucrata Baill. were identified, and both ABA and SA were found to influence their expression. As a key environmental factor, air humidification may enhance the drought stress adaptability of Davidia involucrata Baill. by modulating ABA biosynthesis. The SDRPGs and signaling pathways identified in this study may serve as important candidate targets, providing theoretical guidance and scientific reference for the genetic improvement of drought resistance in Davidia involucrata Baill. and the long‐term conservation of rare plant resources.

Numerous research studies have examined carbon emissions generated from tourism activities. However, the environmental impact of anthropogenic heat release has not attracted researchers’ attention. We apply the tourism heat footprint method to assess the environmental impact of China’s tourism activities. The results indicate that (1) China’s tourism heat footprint increased from 0.99 × 10 3 w/km 2 in 1994 to 7.53 × 10 3 w/km 2 in 2018, with an average annual growth rate of 8.82%. (2) Particularly during high seasons, the tourism heat footprint increases sharply; tourism transportation accounts for the highest proportion of the tourism heat footprint, ranging from 36.50 to 69.07% from 1994 to 2018. (3) The rapid growth in arrivals and transportation-related changes have contributed to the rapid growth of the tourism heat footprint. Advances in science and technology, laws and regulations, environmental pollution constraints, and national macroeconomic policy have helped reduce the tourism heat footprint. Generally, tourism activities caused by a significant increase in income are the root cause of tourism heat footprint growth. (4) Finally, some suggestions, including cultivating a low-energy tourism culture, improving energy efficiency, implementing low-energy policies, and performing spatial-temporal monitoring, are proposed. This paper expands sustainable tourism’s analytical research and enriches the tourism footprint family evaluation process.

Glaciers are distributed in the Nyainqntanglha Mountains, Himalayas, Tanggula Mountains, Gangdise Mountains and Hengduan Mountains in Southwestern China. Daily temperature and precipitation data from 111 stations, together with the records of glacier changes, indicate that temperature patterns during 1961–2008 were consistent with warming at a statistically significant level. Seasonal warming was greatest in autumn and winter. Temperature rise showed a significant relationship with sea surface temperature in the Western Pacific, net longwave radiation flux, altitude, sunshine hours, strengthening anticyclonic circulations in summer and anomalous cyclonic circulation in winter. The increase was more apparent in higher altitude areas than in lower ones. Precipitation variations were less marked than those of temperature, generally showing weak decreasing trends during 1961–2008. Increasing trends were apparent only in spring and winter, when regional trends of precipitation increases with altitude also were evident. The strengthening Western Pacific Subtropical Highs were related to precipitation variation. Against the background of increasing temperature, especially the increasing warming with altitude, the fronts of 32 glaciers and areas of 13 glacial basins have retreated, mass losses of 10 glaciers have been considerable, glacial lakes in six regions have expanded and melt water discharge of four basins has also increased, but these glaciers and basins in our study are only a fraction of the retreating glaciers over southwestern China.

Based on the historical documents and measured data from the active-layer temperature (ALT) at A, B and C locations (4 670, 4 720 and 4 770 m a.s.l.) on Baishui Glacier No. 1, southeastern Tibetan Plateau, this paper analyzed spatial-temporal characteristics of ALT and its relationship with air temperature, and revealed the response of the active layer ice temperature towards climate change in the monitoring period. The results showed that the influence of air temperature on the active-layer ice temperature had a hysteresis characteristic on the upper of ablation zone and the lag period increased gradually with the altitude elevating. The decrease amplitude of ALT in the accumulation period was far below its increase magnitude in the ablation period. At the same time, the mean glacier ice temperatures at 10 m depth ( T 10 ) in A, B and C profile were obviously higher than most of glaciers previously studied. Measured data also showed that the mean ALT increased by 0.24 °C in 0.5–8.5 m depth of the C profile during 28 years from July 11, 1982 to July 10, 2009.

A total of 12 indices of temperature extremes and 11 indices of precipitation extremes at 111 stations in southwestern China at altitudes of 285-4700 m were examined for the period 1961-2008. Significant correlations of temperature extremes and elevation included the trends of diurnal temperature range, frost days, ice days, cold night frequency and cold day frequency. Regional trends of growing season length, warm night frequency, coldest night and warmest night displayed a statistically significant positive correlation with altitude. These characteristics indicated the obvious warming with altitude. For precipitation extreme indices, only the trends of consecutive dry days, consecutive wet days, wet day precipitation and the number of heavy precipitation days had significant correlations with increasing altitude owing to the complex influence of atmospheric circulation. It also indicated the increased precipitation mainly at higher altitude areas, whereas the increase of extreme precipitation events mainly at lowers altitude. In addition, the clearly local influences are also crucial on climate extremes. The analysis revealed an enhanced sensitivity of climate extremes to elevation in southwestern China in the context of recent warming.

Total hours of sunshine are one of the most important factors affecting climate and environment, and its long-term variation is of much concern in climate studies. Trends of temporal and spatial patterns in sunshine hours and related climatic factors over southwestern China are evaluated for the period 1961–2009 based on data from 111 standard meteorological stations. The results showed that southwestern China is experiencing a statistical decrease of sunshine hours, at the rate of 31.9 h/10a during 1961–2009. The decline was particularly strong in summer, whereas it is nonsignificant in winter. Spatially, statistically significant decreases of sunshine hours mainly occurred in lower altitude regions, especially in the Sichuan basin and Guizhou plateau. Sunshine hours have a high correlation with wind speed, relative humidity, precipitation, cloud cover, surface downwards solar radiation flux, and cloud water content, with wind speed showing the strongest relationship to sunshine hours, implicit in the close correlation (temporally and spatially) between the two variables. Changing water vapor and cloud cover influence sunshine hours in southwestern China. In addition, the increased surface downwards solar radiation flux also made some contribution to a rise of sunshine hours during 1991–2009. The larger decreasing trends of sunshine hours at urban stations than rural stations may reflect the effect of urbanization on sunshine hours. Variations are dominated by the comprehensive functions of multiple factors owing to the complex nature of effects on sunshine hours.

Ecological succession itself could be a theoretical reference for ecosystem restoration and reconstruction. Glacier forelands are ideal places for investigating plant succession because there are representative ecological succession records at long temporal scales. Based on field observations and experimental data on the foreland of Baishui number 1 Glacier on Mt. Yulong, the succession and dispersal mechanisms of dominant plant species were examined by using numerical classification and ordination methods. Fifty samples were first classified into nine community types and then into three succession stages. The three succession stages occurred about 9–13, 13–102, and 110–400 years ago, respectively. The earliest succession stage contained the association of Arenaria delavayi + Meconopsis horridula. The middle stage contained the associations of Arenaria delavayi + Kobresia fragilis, Carex capilliformis + Polygonum macrophyllum, Carex kansuensis, and also Pedicularis rupicola. The last stage included the associations of Kobresia fragilis + Carex capilliformis, Kobresia fragilis, Kobresia fragilis + Ligusticum rechingerana, and Kobresia fragilis + Ligusticum sikiangense. The tendency of the succession was from bare land to sparse vegetation and then to alpine meadow. In addition, three modes of dispersal were observed, namely, anemochory, mammalichory, and myrmecochory. The dispersal modes of dominant species in plant succession process were evolved from anemochory to zoochory.

Five years after the implementation of the tourism precision poverty alleviation strategy, how effective it has been in alleviating poverty remains to be tested. This study, through a study of 241 farm households in 10 national tourism poverty alleviation key villages in the Qinba Mountain region of Hanzhong, southern Shaanxi, finds that rural tourism has contributed to a general increase in farm household income, but the effect of income increase varies significantly between households that have escaped poverty and non-poor households, and there is no significant difference in income between those who participate in tourism and those who do not. The study concludes that the poverty-reducing effects of tourism are conditional, with the poor quality of human capital being the main obstacle to farm households’ income growth, the institutional mechanism for tourism participation is inadequate, effective farm household tourism participation is significantly low, and non-farm work constitutes a substitute for farm households’ tourism livelihood options. The primary stage tourism scenic spots have a limited role in driving the income of farming households, and the geographical location limits the effective participation of farming households. Accordingly, the following countermeasures are proposed: (1) in terms of strategic decision-making options, establish a screening mechanism for tourism participation in poverty alleviation and implement diversified poverty governance; (2) in terms of tourism development strategies, encourage the integration of multiple industries and synergistic development, realize the two-way interaction of “+ tourism” and “tourism +”; (3) in terms of development methods, adhere to the participatory development path, improve the institutional mechanism for tourism participation, stimulate the endogenous motivation of farmers, and explore the dynamic participation path of “bottom-up”. (4) In the development of endogenous power, strengthen skills training, improve the comprehensive quality of farmers and their participation level and ability; (5) In the coordination and protection, play the coordinating and leading role of grass-roots party building, and continuously cultivate and strengthen tourism cooperative organizations.