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Subtropical evergreen broadleaved forests distributed in montane zones of southern China experience seasonal droughts and winter frost. Previously, studies have recognized that xylem anatomy is a determinant of its vulnerability to embolism caused by drought and freezing events. We hypothesized that there is a coordination of xylem resistance to freeze-thaw and drought-induced embolism for the subtropical montane evergreen broadleaved tree species because they are influenced by common xylem structural traits (e.g., vessel diameter). We examined the branch xylem anatomy, resistance to drought-induced embolism (P 50 ), and the percent loss of branch hydraulic conductivity after a severe winter frost (PLC winter ) for 15 evergreen broadleaved tree species in a montane forest in South China. Our results showed that P 50 of the studied species ranged from -2.81 to -5.13 MPa, which was not associated with most xylem anatomical properties except for the axial parenchyma-to-vessel connectivity. These tree species differed substantially in PLC winter , ranging from 0% to 76.41%. PLC winter was positively related to vessel diameter and negatively related to vessel density, vessel group index, and vessel-to-vessel connectivity, but no coordination with P 50 . This study suggests that hydraulic adaptation to frost is important to determine the distributional limit of subtropical montane evergreen woody angiosperms., (© 2024 Scandinavian Plant Physiology Society.)

Climate change has resulted in an increase in drought severity in the species-rich tropical and subtropical forests of southern China. Exploring the spatiotemporal relationship between drought-tolerance trait and tree abundance provides a means to elucidate the impact of droughts on community assembly and dynamics. In this study, we measured the leaf turgor loss point (πtlp) for 399 tree species from three tropical forest plots and three subtropical forest plots. The plot area was 1 ha and tree abundance was calculated as total basal area per hectare according to the nearest community census data. The first aim of this study was to explore πtlp abundance relationships in the six plots across a range of precipitation seasonality. Additionally, three of the six plots (two tropical forests and one subtropical forest) had consecutive community censuses data (12-22 years) and the mortality ratios and abundance year slope of tree species were analyzed. The second aim was to examine whether πtlp is a predictor of tree mortality and abundance changes. Our results showed that tree species with lower (more negative) πtlp were more abundant in the tropical forests with relative high seasonality. However, πtlp was not related to tree abundance in the subtropical forests with low seasonality. Moreover, πtlp was not a good predictor of tree mortality and abundance changes in both humid and dry forests. This study reveals the restricted role of πtlp in predicting the response of forests to increasing droughts under climate change., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Karst forests are habitats in which access to soil water can be challenging for plants. Therefore, safe and efficient xylem water transport and large internal water storage may benefit tree growth. In this study, we selected 22 tree species from a primary subtropical karst forest in southern China and measured their xylem anatomical traits, saturated water content (SWC), hydraulic conductivity (Ks) and embolism resistance (P50). Additionally, we monitored growth of diameter at breast height (DBH) in 440 individual trees of various sizes over three consecutive years. Our objective was to analyze the relationships between xylem structure, hydraulic efficiency, safety, water storage and growth of karst tree species. The results showed significant differences in structure but not in hydraulic traits between deciduous and evergreen species. Larger vessel diameter, paratracheal parenchyma and higher SWC were correlated with higher Ks. Embolism resistance was not correlated with the studied anatomical traits, and no tradeoff with Ks was observed. In small trees (5-15 cm DBH), diameter growth rate (DGR) was independent of hydraulic traits. In large trees (>15 cm DBH), higher Ks and more negative P50 accounted for higher DGR. From lower to greater embolism resistance, the size-growth relationship shifted from growth deceleration to acceleration with increasing tree size in eight of the 22 species. Our study highlights the vital contributions of xylem hydraulic efficiency and safety to growth rate and dynamics in karst tree species; therefore, we strongly recommend their integration into trait-based forest dynamic models., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Objective: China adopted an unprecedented province-scale quarantine since January 23rd 2020, after the novel coronavirus (COVID-19) broke out in Wuhan in December 2019. Responding to the challenge of limited testing capacity, large-scale (>20 000 tests per day) standardized and fully-automated laboratory (Huo-Yan) was built as an ad-hoc measure. There is so far no empirical data or mathematical model to reveal the impact of the testing capacity improvement since quarantine. Methods: Based on the suspected case data released by the Health Commission of Hubei Province and the daily testing data of Huo-Yan Laboratory, the impact of detection capabilities on the realization of "clearing" and "clearing the day" of supected cases was simulated by establishing a novel non-linear and competitive compartments differential model. Results: Without the establishment of Huo-Yan, the suspected cases would increase by 47% to 33 700, the corresponding cost of quarantine would be doubled, the turning point of the increment of suspected cases and the achievement of "daily settlement" (all newly discovered suspected cases are diagnosed according to the nucleic acid testing result) would be delayed for a whole week and 11 days. If the Huo-Yan Laboratory could ran at its full capacity, the number of suspected cases could start to decrease at least a week earlier, the peak of suspected cases would be reduced by at least 44%, and the quarantine cost could be reduced by more than 72%. Ideally, if a daily testing capacity of 10 500 tests was achieved immediately after the Hubei lockdown, "daily settlement" for all suspected cases could be achieved. Conclusions: Large-scale, standardized clinical testing platform, with nucleic acid testing, high-throughput sequencing, and immunoprotein assessment capabilities, need to be implemented simultaneously in order to maximize the effect of quarantine and minimize the duration and cost of the quarantine. Such infrastructure, for both common times and emergencies, is of great significance for the early prevention and control of infectious diseases.

Karst and non-karst forests occur in the same region in south-west China, but the soil water and mineral nutrients availability are different between the forests. Our hypothesis was that the leaves of karst trees would be better adapted to dry, nutrient-poor conditions than those of trees in a nearby non-karst forest. We compared the gas exchange, anatomical characteristics and mineral nutrient concentrations in leaves from 21 tree species in a tropical karst forest and 19 species in a nearby non-karst forest in south-west China. We found that the leaves of karst trees had higher P concentrations, photosynthetic capacity and water use efficiency, and greater adaxial and abaxial epidermis thickness than leaves of non-karst forest trees. Evergreen and deciduous trees differed more significantly in leaf functional traits in the karst forest than in the non-karst forest. The leaf palisade:spongy mesophyll thickness ratio was positively correlated with stomatal conductance and negatively correlated with photosynthetic water use efficiency in the karst forest but not in the non-karst forest. Our findings indicate that karst forest trees are more conservative in water use, whereas soil P deficiency could be a major limiting factor for the growth of non-karst forest trees.

As a global biodiversity hotspot, the subtropical evergreen broadleaved forest (SEBF) in southern China is strongly influenced by the humid monsoon climate, with distinct hot-wet and cool-dry seasons. However, the hydraulic strategies of this forest are not well understood. Branch and leaf hydraulic safety margins (HSMbranch and HSMleaf, respectively), as well as seasonal changes in predawn and midday leaf water potential (Ψpd and Ψmd), stomatal conductance (Gs), leaf to sapwood area ratio (AL/AS) and turgor loss point (Ψtlp), were examined for woody species in a mature SEBF. For comparison, we compiled these traits of tropical dry forests (TDFs) and Mediterranean-type woodlands (MWs) from the literature because they experience a hot-dry season. We found that on average, SEBF showed larger HSMbranch and HSMleaf than TDF and MW. During the dry season, TDF and MW species displayed a significant decrease in Ψpd and Ψmd. However, SEBF species showed a slight decrease in Ψpd but an increase in Ψmd. Similar to TDF and MW species, Gs was substantially lower in the dry season for SEBF species, but this might be primarily because of the low atmospheric temperature (low vapor pressure deficit). On the other hand, AL/AS and Ψtlp were not significant different between seasons for any SEBF species. Most SEBF species had leaves that were more resistant to cavitation than branches. Additionally, species with stronger leaf-to-branch vulnerability segmentation tended to have smaller HSMleaf but larger HSMbranch. Our results suggest that SEBF is at low hydraulic risk under the current climate., (© The Author(s) 2019. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

This study was to identify the chemical constituents of Schisandra propinqua, one herbal medicine of Yi nationality in China by using ultra performance liquid chromatography-quadrupole-time of flight-mass spectrometry (UPLC-Q-TOF/MSE). Acetonitrile- water containing 0.1% formic acid was used as the mobile phase for gradient elution. Data were collected under ESI negative mode and ESI positive mode, and then screened and verified by the software of UNIFI and Masslynx4.1. Based on the accurate mass, fragment ions, neutral losses, mass error, retention time, reference substance, isotope information, the intensity of fragments, as well as the previous reports, the known compounds were validated and identified. The chemical structures of the unknown components were identified according to exact molecular weight, MS fragment, chromatographic retention behavior, and characteristic fragments of known congener compounds. A total of 68 chemical components were identified from S. propinqua, including 3 flavonoids, 10 flavanols, 34 lignans compounds (including 20 dibenzocyclooctene lignans), 4 triterpenoids, 17 organic acid and other compounds. 37 compounds of them were found in S. propinqua for the first time, and one potential compound needed to be identified., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

Through planting regionalization the scientific basis for planting area of high-quality medicinal materials was predicted. Through interview investigation and field survey, the distribution information of Corni Fructus in China was collected,and 89 sampling point from 14 producing areas were collected. Climate and topography of Corni Fructus were analyzed, the ecological adaptability of study was conducted based on ArcGIS and Maxent. Different suitability grade at potential areas and regionalization map were formulated. There are nine ecological factors affecting the growth of Corni Fructus, for example precipitation in November and March and vegetation type. The results showed that the most suitable habitats are Henan, Shaanxi, Zhejiang, Chongqing, Hubei, Sichuan, Anhui, Hunan and Shandong province. Using the spatial analysis method,the study not only illustrates the most suitable for the surroundings of Corni Fructus,but also provides a scientific reference for wild resource tending, introduction and cultivation, and artificial planting base and directing production layout., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

Through study on the correlation between atractylodis lactones ingredient content and climatic factors, we research regionalization from climatic of five main producing provinces of the country, in order to provide a scientific basis for atractylodis' conscious cultivation. By sampling from 40 origins which from five main producing provinces of the country, we use SPSS to analysis variation of atractylodis lactones ingredient content in different conditions of climatic factors and the effect of each factors. Then according to the relationship between atractylodis lactones ingredient content and climatic factors, we use ArcGIS to conduct ecological suitability regionalization based on climatic factors. The most suitable climatic condition for cultivation of atractylodis: the wettest month precipitation 220-230 mm, the warmest average temperature 25 degrees C, the average temperature of driest season 10 degrees C.

The distribution information of Lomatogonium rotatum. was collected by interview investigation and field survey, and 55 related environmental factors were collected, the habitat suitability study was conducted based on geographic information system (GIS) and maximum entropy model. The AUCs of ROC curve were both above 0.99, indicating that the predictive results with the maximum model were highly precise. The results showed that 13 major environmental factors have obvious influence on ecology suitability distributions of L. rotatum, including month average temperature of February et al., the suitable distribution areas are mainly concentrated in the east-central of Inner Mongolia, including Hexigten banner, Duolun county, Zhenglan banner et al., The zoning results basically coincide with the genuine producing areas, and further afford new suitable distribution areas, which can provide reference for L. rotatum's wild nursery and the siting of introduction and cultivation.

Through study on the correlation between Atractylodis macrocephala lactones ingredient content and topographic factors, we researched regionalization from topography of five main producing provinces of the country, in order to provide a scientific basis for A. macrocephala reasonable cultivation. By sampling from 40 origins of five main producing provinces of the country, the variation of A. macrocephala lactones ingredient content in different conditions of topographic factors and the effect of altitude, slope and aspect was analyzed by SPSS. Then according to the relationship between A. macrocephala lactones ingredient content and topographic factors, the ecological suitability regionalization was conducted by using ArcGIS based on topographic factors. It is suitable for growth of A. macrocephala in the hilly and mountainous areas of southern whose A. macrocephala lactones ingredient content is in high levels. It is unsuitable for growth of A. macrocephala in Northern plain areas, but we can cultivate A. macrocephala in the hilly and mountainous areas of Northern. The most suitable topographic condition for cultivation of A. macrocephala : altitude 200 meters above, slope 3.00-4.99 degrees.

This paper aims to summarize the achievements during the implementation process of good agricultural practice (GAP) in Chinese Materia Medica (CMM), and on basis of analyzing the existing problems of GAP, to propose further implementation of GAP in TCM growing. Since the launch of GAP in CMM growing ten years ago, it has acquired great achievements, including: (1) The promulgation of a series of measures for the administration of the GAP approval in the CMM growing; (2) The expanded planting area of CMM; (3) The increased awareness of standardized CMM growing among farmers and enterprises; (4) The establishment of GAP implementation bases for CMM growing; (5) The improvement of theory and methodology for CMM growing; (6) The development of a large group of experts and scholars in GAP approval for CMM production. The problems existing in the production include: (1) A deep understanding of GAP and its certification is still needed; (2) The distribution of the certification base is not reasonable; (3) The geo-economics effect and the backward farming practices are thought to be the bottlenecks in the standardization of CMM growing and the scale production of CMM; (4) Low comparative effectiveness limits the development of the GAP; (5) The base of breeding improved variety is blank; (6) The immature of the cultivation technique lead to the risk of production process; (7) The degradation of soil microbial and the continuous cropping obstacle restrict the sustainable development of the GAP base. To further promote the health and orderly GAP in the CMM growing, the authors propose: (1) To change the mode of production; (2) To establish a sound standard system so as to ensure quality products for fair prices; (3) To fully consider the geo-economic culture and vigorously promote the definite cultivating of traditional Chinese medicinal materials; (4) To strengthen the transformation and generalization of basic researches and achievements, in order to provide technical support for the CMM production; (5) To deepen the understanding of GAP, to vigorously promote ecological planting and precision agriculture, in order to overcome the continuous cropping obstacle. The authors think that despite the fact that we are still facing with a huge array of management and technological problems, the GAP in the CMM growing has already enjoyed widespread support and showed great potential. In the future, with people's deeper understanding of GAP and the great progress of the science and technology, the GAP will constantly be fused with the theory, methodology and technology in the modern agriculture like precision agriculture, eco-agriculture and etc.

To study the spatial structure and geographic distribution of major active components in medical herb Dipsacus asperoides population, in Guizhou province, the author obtained the asperosaponin VI content among 38 D. asperoides population points. Using spatial statistic and traditional statistic, the spatial variation pattern has been found. Combining the environment variables, it is tried to reveal the geographic distribution rules between group of major active component in medical herb D. asperoides population and group of environmental factors. The results show: the spatial structure of major active component in medical herb D. asperoides population is randomly distributed in global space, but has two aggregation points which have a high positive correlation in local space; environmental factors value for group of major active component in medical herb D. asperoides population has a large difference in the interior-group, but environmental factors value has a small difference in inter-group.

Objective: To conduct preliminary investigation to the species and reserves of medicinal plants in Huangfu Mountain, and to provide references to the general survey of those plants for medicine., Method: Combined with global positioning system (GPS), the program of investigation with grid sampling was used in this resource survey of medicinal plants., Result: After the preliminary investigation of the plants for medical use of Huangfu Mountain, it is found that there are 103 families with 313 kinds of plants. There are many medicinal plants and large distribution, such as Pseudostellaria heterophylla, Semiaguilegia adoxoides and Pinellia ternate., Conclusion: Huangfu Mount, with so many different kinds of medicinal plants and comfortable environment for part of the medicinal plants to grow, could be developed as a base for planting Chinese herbal medicines.

It is important to understand the ecophysiological characters of plants when exploring mechanisms underlying species substitution in the process of plant succession. In the present study, we selected 34 woody species from different stages of secondary succession in subtropical forests of southern China, and measured their hydraulic conductivity, gas exchange rates, leaf nutrients and drought-tolerance traits such as xylem resistance to cavitation, turgor loss point and carbon isotope ratio. Principal component analysis revealed that early-, mid- and late-successional species were significantly separated along axis 1, which was strongly associated with hydraulic-photosynthetic coordination. In contrast to species distributed in late-successional forest, early-successional species had the highest hydraulic conductivity, net photosynthetic rates, photosynthetic nitrogen and phosphorus use efficiencies, but had the lowest photosynthetic water-use efficiency. However, changes of the measured drought-tolerance traits of the 34 species along the succession did not demonstrate a clear trend - no significant correlations between these traits and plant successional stages were found. Moreover, the trade-off between hydraulic efficiency and safety was not identified. Taken together, our results suggested that hydraulic efficiency and photosynthetic function, rather than drought tolerance, play an important role in species distributions along plant succession in subtropical forests., (© 2012 Blackwell Publishing Ltd.)

Lianas are an important component of tropical forests and often abundant in open habitats, such as tree-fall gaps, forest edges, and disturbed forests. The abundance of lianas in tropical forests has been increasing as a result of global environmental change and increasing forest fragmentation. In order to understand this phenomenon in terms of leaf functional traits and to evaluate their competitive potential, we conducted a cost-benefit analysis of leaves from 18 liana species and 19 tree species in a tropical seasonal rain forest. The results revealed that lianas were scattered in a group distinct from trees along the first axis of a principal component analysis using 15 leaf ecophysiological traits, being located at the quick-return end of the leaf economics spectrum, with higher specific leaf area and photosynthetic rates (A), higher photosynthetic nitrogen (N) and phosphorus (P) use efficiencies, a lower leaf construction cost per unit leaf area (CC) and cost-benefit ratio (CC/A), and a shorter leaf life span (LLS). Trees showed the opposite trends. The results indicate that lianas can grow faster and capture resources more efficiently than trees in disturbed, open habitats. The positive relationship between LLS and CC/A revealed a trade-off between leaf construction cost and benefit over time. The 37 species analyzed had a mean foliar N/P ratio of 20, indicating that the forest was characterized by a P deficit. With an increasing atmospheric CO(2) concentration, the higher nutrient use efficiency could benefit lianas more than trees in terms of productivity, possibly also contributing to the increasing abundance of lianas in nutrient-limited tropical forests.