Posts by Collection

Portfolio item number 1

Short description of portfolio item number 1

Portfolio item number 2

Short description of portfolio item number 2

气候变化下西南地区12种常见针叶树种适宜分布区预测

Published in November 1, 2019

目的:随气候变化加剧，未来西南地区针叶林分布存在诸多不确定性，进行未来气候下西南地区常见针叶树种适宜分布区研究，为该地区森林生态安全评估提供参考。方法:基于最大熵模型(MaxEnt)模拟未来气候情景下西南地区常见的12种针叶树的气候适宜分布区。结果:MaxEnt模型能够很好地模拟西南地区12个树种的潜在分布，AUC 值均达0．9以上; 2070年MPI-ESM-LＲ模式ＲCP4．5情景下西南地区12种常见针叶树种气候适宜区面积分布变化显著，包括冷杉、三尖杉、杉木、干香柏、柏木、水杉、云南松、红豆杉和福建柏在内的9个树种气候适宜区与气候最适区面积增加11．1% ～ 412．8%; 银杉和油麦吊云杉的气候适宜区面积分别增加6.0%和32.8%，但气候最适区面积减少了0．8%和3．5%; 云南油杉未来气候适宜区和气候最适区的面积则减少24．0%和29．1%。结论:西南地区针叶林中广布树种的气候适宜区面积会得益于气候变化而扩大，但云南油杉和油麦吊云杉等一些西南特有乡土树种的气候适宜区面积则会因为气候变化而缩小，因此对特有乡土树种的保护应给予重视。

Recommended citation: 陈禹衡, 吕一维, 殷晓洁. 气候变化下西南地区12种常见针叶树种适宜分布区预测［J］. 南京林业大学学报(自然科学版), 2019, 43(6): 113-120.
Download Paper

西南地区松属乔木对气候变化的响应

Published in September 1, 2020

通过收集中国西南地区12种松属乔木的分布点数据，结合当前及未来(2070年)气候情景数据，基于最大熵模型预测松属乔木潜在地理分布，分析潜在分布区的环境特征，旨在为气候变化下松属乔木资源的保护以及可持续经营提供理论参考。结果表明: 模型的受试者工作特征曲线下的面积(AUC)均大于0．8，预测精度达到“很准确”水平。12种松属乔木中，细叶云南松的潜在分布范围最窄，马尾松的分布范围最广。2070年代表性浓度路径4．5 (representative concentration pathway 4．5，ＲCP4．5) 情景下，12种松属乔木的适宜区在面积和空间上均发生了不同程度的变化，且整体上呈现向东偏北或西偏北方向扩张的趋势。乔松、思茅松、细叶云南松、云南松、高山松、华山松和油松的适宜分布区总体呈现扩张趋势，而细叶云南松和油松高适宜区面积则减小; 巴山松、毛枝五针松、白皮松、华南五针松和马尾松的适宜区呈缩小趋势。8 个主导环境因子在松属乔木适宜区内的平均变化范围分别为: 年降水量647～2600mm，最冷月最低气温－8～10℃，气温的季节性358～756，海拔281～3054m，等温性25～45，气温日较差6～11℃，降水的季节性43～99，适宜区土壤质地主要为轻黏土、粉壤土和砂黏壤土。该结果对松属植物资源的保护、造林区规划以及可持续经营等具有一定指导意义。

Recommended citation: 陆双飞, 陈禹衡, 周斯怡, 殷晓洁. 西南地区松属乔木对气候变化的响应［J］. 森林与环境学报, 2020, 40(5): 466-477.
Download Paper

Patterns of tree species richness in Southwest China

Published in January 28, 2021

As a region known for its high species richness, southwest China plays an important role in preserving global biodiversity and ensuring ecological security in the Yangtze, Mekong, and Salween river basins. However, relatively few studies focus on the response of tree species richness to climate change in this part of China. This study determined the main tree species in southwest China using the Vegetation Map of China and the Flora of China. From simulations of 1970 to 2000 and three forecasts of future benign, moderate, and extreme climate warming anticipated during 2061 to 2080, this study used a maximum entropy model (MaxEnt) to simulate main tree species richness in southwest China. Regions with a peak species richness at intermediate elevations were typically dominated by complex mountainous terrain, such as in the Hengduan Mountains. Likewise, regions with the smallest richness were low-elevation areas, including the Sichuan Basin, and the high-elevation Sichuan-Tibet region. Annual precipitation, minimum temperature of the coldest month, temperature seasonality, and elevation were the most critical factors in estimating tree species richness in southwest China. During future 2061 to 2080 climate scenarios, tree species tended to migrate towards higher elevations as mean temperatures increased. For climate change scenarios RCP2.6–2070 (benign) and RCP4.5–2070 (moderate), the main tree species richness in the study area changed little. During the RCP8.5–2070 extreme scenario, tree species richness decreased. This study provides useful guidance to plan and implement measures to conserve biodiversity.

Recommended citation: Lu, S., Zhou, S., Yin, X., Zhang, C., Li, R., Chen, J., ... Chen, Y. 2021. Patterns of tree species richness in Southwest China. Environmental Monitoring and Assessment, 193: 97.
Download Paper

黄檀属珍稀树种未来适宜区变化预测

Published in January 28, 2021

目的：黄檀属Dalbergia树种具有很高的经济价值，但物种野外种群受到了严重的破坏。随着气候变化的加剧，该属物种分布存在着较高的不确定性，迫切需要深入认识这些物种未来分布的趋势，以便更好地进行保护。 方法：利用最大墒(MaxEnt)模型，基于当前气候环境，对列入中国生物多样性红色名录的7种黄檀属珍稀乔木树种在中国的适宜分布区进行了预测，并对未来不同气候情景下其分布区的变化进行了分析。 结果：年平均温度、等温性、气温季节变动系数、最热季降水量、最干月降水量、最干季降水量、土壤碳酸盐含量与坡度是影响7种黄檀属珍稀乔木适宜区分布模拟的关键环境因子。黄檀属珍稀乔木除黄檀D. hupeana外均将在未来获得更大的适宜分布区。黄檀的适宜分布区面积与最适分布区面积则均有所减小，其中适宜分布区面积将减小30.8%，最适分布区则将缩小49.3%。 结论：由于分布区存在差异，同属不同物种的未来分布对气候变化的响应不同，未来的保护工作应当集中在黄檀等适宜分布区缩小的物种上。

Recommended citation: 陈禹衡, 陆双飞, 毛岭峰. 黄檀属珍稀树种未来适宜区变化预测［J］. 浙江农林大学学报, 2021, 38(4): 837-845.
Download Paper

基于气候与物种扩散的破坏草入侵区域对未来气候变化的响应

Published in January 28, 2022

目的：破坏草是中国西南地区危害最为严重的入侵物种之一，每年在当地造成巨额的经济损失。扩散能力与入侵物种的危害性有关，也是决定其分布范围的重要因素，但在目前物种潜在分布和潜在入侵区域的研究中却常常被忽略。 方法：本研究旨在基于物种扩散量化气候变化背景下破坏草的入侵区域，应用最大熵（MaxEnt）模型对破坏草潜在适宜区进行预测，在得出其2050年和2070年中等温室气体排放情景（SSPs45）下适宜分布区后，基于当前分布使用细胞自动机在适宜区内模拟了破坏草的扩散，预测了2050年和2070年一般气候排放情景下破坏草的潜在入侵区域。 结果：气温季节性变动系数、最冷月最低气温、最干季降水量、年降水量、最冷季降水量是影响破坏草分布的重要气候因子。破坏草的适宜分布区将从当前的79.68 × 104 km2增长为2050年的120.26 × 104 km2，之后于2070年有所缩小，但面积仍达111.97 × 104 km2。与当前破坏草分布地区相比，2050 SSPs45情景下破坏草潜在入侵区域将增加至88.27 × 104 km2，到2070年则将增加至95.35 × 104 km2。 结论：破坏草潜在入侵区域受到扩散速度限制，始终小于其适宜分布区，但随着气候变化逐步增加。受全球气候变化影响，未来四川、贵州、广西等省份应当采取进一步措施以控制破坏草的蔓延。预测结果一定程度反映了入侵物种的时空格局，可以为入侵物种防控提供科学依据。

Recommended citation: 陈禹衡, 陆家祎, 吴鹏飞, 毛岭峰. 基于气候与物种扩散的破坏草入侵区域对未来气候变化的响应［J］. 北京林业大学学报, 2022, 44(1): 69-76.
Download Paper

Combining the Effects of Global Warming, Land Use Change and Dispersal Limitations to Predict the Future Distributions of East Asian Cerris Oaks (Quercus Section Cerris, Fagaceae) in China

Published in February 22, 2022

Species shift their ranges in response to climate change (CC). However, they may not be able to track optimal conditions as soon as possible, due to limited dispersal ability or habitat fragmentation, caused by land use and land cover change (LULC). This study aimed to explore the combined impacts of CC, LULC and dispersal limitations on the future range dynamics of Quercus acutissima Carruth., Q. variabilis Blume and Q. chenii Nakai, three dominant Cerris oak tree species in warm-temperate and subtropical deciduous forests of China. We used the Maximum Entropy (Maxent) algorithm to predict the suitable habitats for the years 2050 and 2070, under three representative concentration pathways (RCPs). Habitat fragmentation patterns were examined to assess the influence of LULC. Two migration scenarios (full- and partial-migration) were compared to evaluate the effect of dispersal limitations. We found that annual precipitation (AP), minimum temperature in the coldest month (MTCM) and temperature seasonality (TS) play a key role in determining the present distributions of Q. chenii, while AP, MTCM and annual mean temperature (AMT) contribute the most to the distribution models of Q. variabilis and Q. acutissima. For all the three species, LULC will increase the level of habitat fragmentation and lead to the loss of core areas, while limited dispersal ability will restrict the accessibility of future potentially suitable habitats. Under the scenarios of CC and LULC, the suitable areas of Q. chenii will decrease sharply, while those of Q. variabilis in South China will become unsuitable. Our findings highlight the importance of considering dispersal ability, as well as land use and land cover change, for modeling species’ range shifts in the face of global warming. Our study also provides vital information for guiding the management of East Asian Cerris oaks in China; Q. chenii should be listed as a species requiring priority protection, and the threatened habitats of Q. variabilis should be protected to buffer the impacts of CC and LULC.

Recommended citation: Chen, Y., Li, Y., Mao, L. 2022. Combining the Effects of Global Warming, Land Use Change and Dispersal Limitations to Predict the Future Distributions of East Asian Cerris Oaks (Quercus Section Cerris, Fagaceae) in China. Forests, 2022, 13: 367.
Download Paper

Diversity patterns and drivers of soil bacterial and fungal communities along elevational gradients in the Southern Himalayas, China

Published in June 14, 2022

Elucidating the diversity patterns and drivers of soil microbes at high altitudes contributes to understanding the role microbes play in ecosystem services, but little is known about the soil microbial diversity, richness and abundance patterns across elevations on the Tibetan Plateau. This study was conducted to explore the shifts of forest soil bacterial and fungal community diversities and the regulating factors along an elevation gradient (2980–4050 m a.s.l.) in the Southern Himalayas of China. Illumina sequencing of 16S rRNA and ITS1, and quantitative real-time PCR were used to determine soil bacterial and fungal communities, coupled with plant diversity survey and edaphic properties analysis. The results revealed that plant alpha-diversity reached the highest level at an elevation of 3255 m and subsequently decreased with higher elevations; while soil bacterial alpha-diversity and fungal richness reached the lowest at 3590 m and 3772 m respectively, then increased with higher elevations; soil microbial abundance decreased with increasing elevation. The soil pH was the main driver of the elevation-related soil bacterial richness, diversity, and abundance. Soil nutrients contributed most to the fungal richness, diversity, and abundance. The total phosphorus content was the optimal predictor of fungal richness and abundance, while nitrate levels determined the fungal diversity. The community structures of bacteria and fungi differed significantly among elevations (Pbacteria = 0.001, Pfungi = 0.001). The elevation and edaphic properties (including the contents of soil organic matter and pH) controlled the elevation patterns of soil bacterial community structures and explained 56.1 % of the total variation. In contrast, edaphic properties (including SOC, TP and pH) primarily shaped the elevation patterns of soil fungal community structures and explained 38.7 % of the total variation. This study provides comprehensive insights into soil microbial geography associated with the biogeochemical cycling on the Tibetan Plateau.

Recommended citation: Yang, N., Li, X., Liu, D., Zhang, Y., Chen, Y., Wang, B., ... Mao, L. 2022. Diversity patterns and drivers of soil bacterial and fungal communities along elevational gradients in the Southern Himalayas, China. Applied Soil Ecology, 2022, 178: 104563.
Download Paper

基于土地利用变化的江苏盐城湿地然保护区生境质量评估

Published in September 15, 2022

目的: 研究江苏盐城湿地自然保护区的土地利用格局、生境质量变化情况,为提升生物多样性保护水平、改善区域生态环境质量提供依据。方法: 基于2000—2018年5期盐城湿地珍禽国家级自然保护区(简称盐城自然保护区)土地利用数据,运用土地利用转移矩阵和InVEST模型,研究盐城自然保护区土地利用时空演变格局以及生境质量的动态变化,对盐城自然保护区的生境退化程度和生境质量进行评估。结果: 2000—2018年盐城自然保护区土地利用类型转变明显,主要是其他建设用地向水库坑塘的转变;研究期内盐城自然保护区生境退化程度不断加深,而且保护区内中度退化和高度退化的区域面积持续增加;生境质量指数总体呈现上升的趋势,且高生境质量的区域面积增加。结论: 盐城自然保护区土地利用类型频繁变化导致生境退化程度加深,但总体上保护区的生境状况逐渐改善,因此进一步优化盐城自然保护区的功能区划、遏制土地利用类型的频繁转变,成为提升盐城自然保护区生境质量和生物多样性保护成效的有效途径。

Recommended citation: 李潇,杨加猛,陈禹衡,等. 基于土地利用变化的江苏盐城湿地自然保护区生境质量评估[J]. 南京林业大学学报（自然科学版）, 2022, 46(5): 169-176.
Download Paper

Extinction risk of Chinese angiosperms varies between woody and herbaceous species

Published in February 1, 2023

Aim Understanding how species’ traits and environmental contexts relate to extinction risk is a critical priority for ecology and conservation biology. This study aims to identify and explore factors related to extinction risk between herbaceous and woody angiosperms to facilitate more effective conservation and management strategies and understand the interactions between environmental threats and species’ traits.

Recommended citation: Chen, Y.; Wu, Y.; Dong, Y.; Li, Y; Ge, Z.; George, O.; Feng, G.; Mao, L. 2023. Extinction risk of Chinese angiosperms varies between woody and herbaceous species. Diversity and Distributions, 29(2), 232-243.
Download Paper

Geographical patterns and determinants in plant reproductive phenology duration

Published in June 15, 2023

Abstract Biodiversity is and always has been an important issue in ecological research. Biodiversity can reflect niche partitioning among species at several spatial and temporal scales and is generally highest in the tropics. One theory to explain it is that low-latitude tropical ecosystems are dominated by species that are generally only distributed over a narrow area. This principle is known as Rapoport’s rule. One previously unconsidered extension of Rapoport’s rule may be reproductive phenology, where variation in flowering and fruiting length may reflect a temporal range. Herein, we collected reproductive phenology data for more than 20,000 species covering almost all angiosperm species in China. We used a random forest model to quantify the relative role of seven environmental factors on the duration of reproductive phenology. Our results showed that the duration of reproductive phenology decreased with latitude, although there was no obvious change across longitudes. Latitude explained more of the variation in the duration of flowering and fruiting phases in woody plants than in herbaceous plants. Mean annual temperature and the length of the growing season strongly influenced the phenology of herbaceous plants, and average winter temperature and temperature seasonality were important drivers of woody plant phenology. Our result suggests the flowering period of woody plants is sensitive to temperature seasonality, while it does not influence herbaceous plants. By extending Rapoport’s rule to consider the distribution of species in time as well as space, we have provided a novel insight into the mechanisms of maintaining high levels of diversity in low-latitude forests.

Recommended citation: Wang, X.; Morin, X.; Jiang, J.; Chen, G.; Mao, L.; Chen, Y.; Song, Z.; Du, Y.; Ma, K. 2023. Geographical patterns and determinants in plant reproductive phenology duration. Frontiers in Plant Science, 14, 1199316.
Download Paper

Drought intensity and post-drought precipitation determine vegetation recovery in a desert steppe in Inner Mongolia, China

Published in January 1, 2024

Abstract Extreme drought events are expected to increase in frequency and severity, posing significant threats to ecosystems worldwide. While considerable research has been concentrated on the effects of climate extremes on the stability of grasslands, the process by which grassland productivity may recover after extreme drought events are still not well understood. Here, we conducted a four-year (2019–2022) recovery investigation after four-year’s (2015–2018) extreme drought treatments of different intensities (control, press and pulse) to explore the vegetation recovery of desert-grassland ecosystems Inner Mongolia, China. Press drought involved a 66 % reduction in natural precipitation from May to August, while pulse drought reduced it by 100 % during June and July. We found that both press and pulse droughts led to a sharp decrease in aboveground net primary productivity (ANPP) after four years, primarily due to reduced growth, density, and productivity of annual and perennial plants. However, ANPP under pulse drought could recover fully after four years of stopping of drought treatment, and it could not under press drought. Additionally, community structure (i.e., species richness, plant density, and height) fully recovered within 1 year after the end of the two extreme drought treatments. Both plant density and height contributed to the ANPP recovery after press and pulse droughts. Structural equation modeling (SEM) results further revealed that the reduction in ANPP during the extreme drought was primarily due to a decrease in plant density caused by reduced soil water content. The recovery of ANPP in pulse drought was directly caused by increased soil water content in the post-extreme drought. These results suggest that drought intensity and precipitation determine ANPP recovery in a degraded desert steppe. Our findings are crucial for deepening understanding of the processes and mechanisms of ecosystem recovery after extreme drought, as well as for the successful management and protection of grassland ecosystems.

Recommended citation: Li, X.; Song, Z.; Hu, Y.; Qiao, J.; Chen, Y.; Wang, S.; Yue, P.; Chen, M.; Ke, Y.; Xu, C.; Yu, Q.; Zuo, X. 2024. Drought intensity and post-drought precipitation determine vegetation recovery in a desert steppe in Inner Mongolia, China. Science of The Total Environment, 906, 167449.
Download Paper

More than just pandas: Urgent research needed on Chinese native plant biodiversity

Published in January 1, 2024

Abstract Conservation of threatened species is essential for achieving sustainable development goals and realizing ecological civilization in China. However, our new survey on endemic threatened angiosperms in the scientific publication database showed that there is still a serious bias in the species’ selection and research topics. China’s 2117 endemic threatened angiosperm species remain relatively understudied with 41 % of them being not included in any Chinese-language and English-language scientific publications. Furthermore, only 2 % of the 44,383 publications that mention threatened plant species are related to conservation research and over 75 % of them are found behind a paywall. We propose measures to increase and advance conservation research and protection for China’s threatened plants, 1. improve long-term and comprehensive research on endemic threatened angiosperms in China, 2. combine conservation research and practices and transfer conservation knowledge to practices timely, 3. promote inter-governmental communication and cooperation, and 4. apply new technologies and methods to conservation studies and practices.

Recommended citation: Chen, Y.; Li, Y.; Dong, Y.; Zhang, M.; Yang, Y.; Primack, R.B.; Barry, K.E.; Mao, L. 2024. More than just pandas: Urgent research needed on Chinese native plant biodiversity. Biological Conservation, 289, 110388.
Download Paper

Lysimeter & EcoTron Workshop 2024

Published: March 19, 2024

Using Ecotrons to separate the effects of above and belowground drought

Global climate change, especially drought, weakens grassland ecosystem functions. To Separate the effects of air and soil drought on grassland plants, we utilized the NPEC Ecotron facility to disentangle the effects of aboveground and belowground drought on the aboveground and belowground functional traits of grassland plants grown as mono- or polycultures. The results will advance our understanding of biodiversity and drought impacts on grassland ecosystems.