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Life forms affect beta-diversity patterns of larch forests in China

Plant Diversity 2024年第1期46卷 49-58页

作者： Wenjing fang Qiong Cai Chengjun Ji Jiangling Zhu Zhiyao Tang jingyun fang School of Ecology and Environmental Science Yunnan UniversityKunming 650091China Department of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871China

Beta-diversity reflects the spatial changes in community species composition which helps to understand how communities are assembled and biodiversity is formed and maintained. Larch(Larix) forests, which are coniferous forests widely distributed in the mountainous and plateau areas in North and Southwest China, are critical for maintaining the environmental conditions and species diversity. Few studies of larch forests have examined the beta-diversity and its constituent components(species turnover and nestedness-resultant components). Here, we used 483 larch forest plots to determine the total betadiversity and its components in different life forms(i.e., tree, shrub, and herb) of larch forests in China and to evaluate the main drivers that underlie this beta-diversity. We found that total betadiversity of larch forests was mainly dependent on the species turnover component. In all life forms,total beta-diversity and the species turnover component increased with increasing geographic, elevational, current climatic, and paleoclimatic distances. In contrast, the nestedness-resultant component decreased across these same distances. Geographic and environmental factors explained 20%-25% of total beta-diversity, 18%-27% of species turnover component, and 4%-16% of nestedness-resultant component. Larch forest types significantly affected total beta-diversity and species turnover component. Taken together, our results indicate that life forms affect beta-diversity patterns of larch forests in China, and that beta-diversity is driven by both niche differentiation and dispersal limitation. Our findings help to greatly understand the mechanisms of community assemblies of larch forests in China.

关键词： Beta-diversity Species turnover Nestedness-resultant Geographic distance Climatic distance Larch forest

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Robust route to H_(2)O_(2)and H_(2)via intermediate water splitting enabled by capitalizing on minimum vanadium-doped piezocatalysts

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Nano Research 2022年第9期15卷 7986-7993页

作者： Yuekun Li Li Li fangyan Liu Biao Wang Feng Gao Chuan Liu jingyun fang Feng Huang Zhang Lin Mengye Wang School of Materials Sun Yat-Sen UniversityShenzhen 518107.State Key Laboratory of Optoelectronic Materials and TechnologiesSun Yat-Sen UniversityGuangzhou 510275China School of Environment and Energy Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and RecyclingSouth China University of TechnologyGuangzhou 510006China School of Metallurgy and Environment Central South UniversityChangsha 410083China Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology School of Environmental Science and EngineeringSun Yat-Sen UniversityGuangzhou 510275China The Guangdong Province Key Laboratory of Display Material and Technology School of Electronics and Information TechnologySun Yat-Sen UniversityGuangzhou 510275China

H_(2)O_(2)is an environmentally friendly chemical for a wide range of water treatments.The industrial production of H_(2)O_(2)is an anthraquinone oxidation process,which,however,consumes extensive energy and produces pollution.Here we report a green and sustainable piezocatalytic intermediate water splitting process to simultaneously obtain H_(2)O_(2)and H_(2)using single crystal vanadium(V)-doped NaNbO_(3)(V-NaNbO_(3))nanocubes as catalysts.The introduction of V improves the specific surface area and active sites of NaNbO_(3).Notably,V-NaNbO_(3)piezocatalysts of 10 mg exhibit 3.1-fold higher piezocatalytic efficiency than the same catalysts of 50 mg,as more piezocatalysts lead to higher probability of aggregation.The aggregation causes reducing active sites and decreased built-in electric field due to the neutralization between different nano-catalysts.Remarkably,piezocatalytic H_(2)O_(2)and H_(2)production rates of V-NaNbO_(3)(10 mol%)nanocubes(102.6 and 346.2μmol·g^(−1)·h^(−1),respectively)are increased by 2.2 and 4.6 times compared to the as-prepared pristine NaNbO_(3)counterparts,respectively.This improved catalytic efficiency is attributed to the promoted piezo-response and more active sites of NaNbO_(3)catalysts after V doping,as uncovered by piezoresponse force microscopy(PFM)and density functional theory(DFT)simulation.More importantly,our DFT results illustrate that inducing V could reduce the dynamic barrier of water dissociation over NaNbO_(3),thus enhancing the yield of H_(2)O_(2)and H_(2).This facile yet robust piezocatalytic route using minimal amounts of catalysts to obtain H_(2)O_(2)and H_(2)may stand out as a promising candidate for environmental applications and water splitting.

关键词： water splitting H_(2)evolution H_(2)O_(2)production piezocatalysis vanadium-doped NaNbO_(3)

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Satellite-based Studies on Large-Scale Vegetation Changes in China

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Journal of Integrative Plant Biology 2012年第10期54卷 713-728页

作者： Xia Zhao Daojing Zhou jingyun fang State Key Laboratory of Vegetation and Environmental Change Institute of Botany the Chinese Academy of SciencesBeijing 100093 China Department of Ecology College of Environmental Sciences and Key Laboratory of Earth Surface Processes of the Ministry of EducationPeking University Beijing 100871 China

Remotely-sensed vegetation indices, which indicate the density and photosynthetic capacity of vegetation, have been widely used to monitor vegetation dynamics over broad areas. In this paper, we reviewed satellite-based studies on vegetation cover changes, biomass and productivity variations, phenological dynamics, desertification, and grassland degradation in China that occurred over the past 2-3 decades. Our review shows that the satellite-derived index （Normalized Difference Vegetation Index, NDVI） during growing season and the vegetation net primary productivity in major terrestrial ecosystems （for example forests, grasslands, shrubs, and croplands） have significantly increased, while the number of fresh lakes and vegetation coverage in urban regions have experienced a substantial decline. The start of the growing season continually advanced in China＇s temperate regions until the 1990s, with a large spatial heterogeneity. We also found that the coverage of sparsely-vegetated areas declined, and the NDVI per unit in vegetated areas increased in arid and semi-arid regions because of increased vegetation activity in grassland and oasis areas. However, these results depend strongly not only on the periods chosen for investigation, but also on factors such as data sources, changes in detection methods, and geospatial heterogeneity. Therefore, we should be cautious when applying remote sensing techniques to monitor vegetation structures, functions, and changes.

关键词： Normalized Difference Vegetation Index （NDVI） phenology remote sensing vegetation coverage vegetation degradation vegetation productivity

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Yield and quality properties of silage maize and their influencing factors in China

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Science China(Life Sciences) 2022年第8期65卷 1655-1666页

作者： Mengying Zhao Yinping Feng Yue Shi Haihua Shen Huifeng Hu Yongkai Luo Longchao Xu Jie Kang Aijun Xing Shaopeng Wang jingyun fang State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871China

Silage maize(Zea mays L.) is one of the most important forages in the world, and its yield and quality properties are critical parameters for livestock production and assessment of forage values. However, relationships between its yield and quality properties and the controlling factors are not well documented. In this study, we collected 5,663 observations from 196 publications across the country to identify the relationships between yield and quality properties of silage maize and to assess the impact of management practices and climatic factors on its yield and quality in China. The average dry matter yield of silage maize was(19.98±6.93) Mg ha^(-1), and the average value of crude protein, ether extract, crude ash, crude fiber, acid detergent fiber, neutral detergent fiber, nitrogen-free extract, and relative feed value was 7.86%±1.71%, 2.53%±1.01%, 5.05%±1.66%,23.97%±6.34%, 27.62%±7.12%, 51.60%±9.85%, 59.68%±7.72%, and 131.17±31.49, respectively. In general, its nutritive value decreased as its yield increased. Increasing planting density could increase the yield but inhibit the nutritive values, while increasing fertilization could benefit the nutritive values. Geographically, the yield increased and the nutritive value decreased from warm(south) to cold(north) regions. The length of growth duration was a major controlling factor for the patterns of these properties. Our findings provide insights for police-makers to make strategy for achieving high yield and good quality of silage maize and help local people to implement better management practices.

关键词： silage maize yield quality management practices climatic factors

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Latitudinal and elevational patterns of phylogenetic structure in forest communities in China’s mountains

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Science China(Life Sciences) 2020年第12期63卷 1895-1904页

作者： Gheyur Gheyret Yanpei Guo jingyun fang Zhiyao Tang Institute of Ecology College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of Ministry of EducationPeking UniversityBeijing 100871China

The phylogenetic structure incorporates both ecological and evolutionary processes to explain assembly of a local community.The "phylogenetic niche conservatism"(PNC) hypothesis suggests that distributions of species along environmental gradients reflect both ancestral traits and ecological fitness of individual species. The temperature is generally regarded to change in similar ways along both latitudinal and elevational gradients but with different historical contingence. Therefore, comparing the latitudinal and elevational patterns of phylogenetic structure of communities is of help to depict the effects of ecological and evolutionary processes in shaping the community assembly. In this study, we explored the latitudinal, elevational and climatic patterns of phylogenetic structure of 569 angiosperm tree communities from 38 mountains across China. We found a larger mean abundance-weighted net relatedness index(NRI) than the presence/absence-based NRI;and the NRI decreased when the species pool downscaled from the full pool to county-level pool. The mean family age and phylogenetic species evenness decreased with latitude, and increased with temperature of the coldest month and precipitation;whilst NRI increased with latitude, and decreased with mean temperature of the coldest month. In most mountains, NRI, mean family age and phylogenetic species evenness showed non-significant trends along the elevational gradient. Our results support the main predictions of PNC for the latitudinal gradient, i.e., species tend to be more phylogenetically related to each other and clades are younger in temperate environments,compared to those in tropical environments. We suggested that independent species pools and abundance should be incorporated in analysis to fully represent the phylogenetic structure of communities.

关键词： community assembly phylogenetic niche conservatism phylogenetic structure environmental filtering species abundance species pool

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DBP formation from degradation of DEET and ibuprofen by UV/chlorine process and subsequent post-chlorination

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Journal of Environmental Sciences 2017年第8期29卷 146-154页

作者： Ehsan Aghdam Yingying Xiang Jianliang Sun Chii Shang Xin Yang jingyun fang Department of Civil and Environmental Engineering Hong Kong University of Science and Technology Kowioon Hong Kong China Hong Kong Branch of the Chinese National Engineering Research Center for Control & Treatment of Heavy Metal Pollution Hong Kong University of Science and Technology Kowloon Hong Kong China School of Environmental Science and Engineering Sun Yat-sen University Guangzhou China

The formation of disinfection by-products（DBPs） from the degradation of N,N-diethyl-3-methyl benzoyl amide（DEET） and ibuprofen（IBP） by the ultraviolet irradiation（UV）/chlorine process and subsequent post-chlorination was investigated and compared with the UV/H_2O_2 process.The pseudo first-order rate constants of the degradation of DEET and IBP by the UV/chlorine process were 2 and 3.1 times higher than those by the UV/H_2O_2 process, respectively, under the tested conditions. This was due to the significant contributions of both reactive chlorine species U（RCS） and hydroxyl radicals（HO） in the UV/chlorine process. Trichloromethane, 1,1,1-trichloro-2-propanone and dichloroacetic acid were the major known DBPs formed after 90% of both DEET and IBP that were degraded by the UV/chlorine process. Their yields increased by over 50%after subsequent 1-day post-chlorination. The detected DBPs after the degradation of DEET and IBP comprised 13.5% and 19.8% of total organic chlorine（TOCl）, respectively, and the proportions increased to 19.8% and 33.9% after subsequent chlorination, respectively. In comparison to the UV/H_2O_2 process accompanied with post-chlorination, the formation of DBPs and TOCl in the UV/chlorine process together with post-chlorination was 5%–63% higher,Ulikely due to the generation of more DBP precursors from the attack of RCS, in addition to HO.

关键词： Pharmaceuticals and personal care products Disinfection by-products UV/chlorine process UV/H2O2 process Chlorination

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Global patterns and climatic drivers of above-and belowground net primary productivity in grasslands

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Science China(Life Sciences) 2021年第5期64卷 739-751页

作者： Yuanfeng Sun Yuanhe Yang Xia Zhao Zhiyao Tang Shaopeng Wang jingyun fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

Understanding patterns and determinants of net primary productivity(NPP)in global grasslands is ongoing challenges,especially for belowground NPP(BNPP)and its fraction(fBNPP).By developing a comprehensive field-based dataset,we revealed that,along with gradients of mean annual precipitation,actual evapotranspiration,and aridity,aboveground NPP(ANPP),BNPP,and total NPP(TNPP)exhibited hump-shaped patterns,whereas fBNPPshowed an opposite trend.ANPP and TNPP showed positive correlations with mean annual temperature,but fBNPPwas negatively correlated with it.The relationship between BNPP and climatic factors was considerably weak,indicating that BNPP was relatively stable regardless of the climate conditions.We also observed that the sensitivities of ANPP and BNPP to interannual temperature variability and those of BNPP to interannual precipitation fluctuations exhibited large variations among different study sites,and differed from those at the spatial scale.In contrast,the temporal sensitivities of ANPP to interannual precipitation variability were highly similar across all the individual sites and much smaller than those at the spatial scale.Overall,these results highlight that precipitation,temperature and evapotranspiration all play vital roles in shaping ANPP pattern and its partitioning to belowground and that the patterns of BNPP along climatic gradients do not mirror those of the ANPP.

关键词： net primary productivity productivity partition climate change grasslands precipitation temperature

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Toward accurate accounting of ecosystem carbon stock in China's forests

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Science Bulletin 2016年第24期61卷 1888-1889页

作者： Huifeng Hu Yuanhe Yang jingyun fang State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of SciencesBeijing 100093 China Department of Ecology College of Urban and Environmental Science Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Beijing 100871 China

Forests play a dominant role in the global terrestrial carbon(C)cycle due to their huge area and large capacity for C stock and productivity[1–4].They occupy around 30%of the global land surface with about 4.2×10~9h... 详细信息

关键词：森林生态系统碳储量中国热带常绿阔叶林核算森林面积造林项目陆地生物圈

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Variations of root and heterotrophic respiration along environmental gradients in China’s forests

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Journal of Plant Ecology 2013年第5期6卷 358-367页

作者： Pin Li Yuanhe Yang jingyun fang Department of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

Aims Root and heterotrophic respiration may respond differently to environmental variability,but little evidence is available from largescale observations.Here we aimed to examine variations of root and heterotrophic respiration across broad geographic,climatic,soil and biotic gradients.Methods We conducted a synthesis of 59 field measurements on root and heterotrophic respiration across China’s forests.Important Findings Root and heterotrophic respiration varied differently with forest types,of which evergreen broadleaf forest was significantly different from those in other forest types on heterotrophic respiration but without statistically significant differences on root respiration.The results also indicated that root and heterotrophic respiration exhibited similar trends along gradients of precipitation,soil organic carbon and satellite-indicated vegetation growth.However,they exhibited different relationships with temperature:root respiration exhibited bimodal patterns along the temperature gradient,while heterotrophic respiration increased monotonically with temperature.Moreover,they showed different relationships with MOD17 GPP,with increasing trend observed for root respiration whereas insignificant change for heterotrophic respiration.In addition,root and heterotrophic respiration exhibited different changes along the age sequence,with insignificant change for root respiration and decreasing trend for heterotrophic respiration.Overall,these results suggest that root and heterotrophic respiration may respond differently to environmental variability.Our findings could advance our understanding on the different environmental controls of root and heterotrophic respiration and also improve our ability to predict soil CO_(2) flux under a changing environment.

关键词： enhanced vegetation index forest age heterotrophic respiration latitude mean annual temperature mean annual precipitation root respiration GPP

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中国落叶栎林群落结构特征及气候和人类活动的影响

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Journal of Plant Ecology 2022年第2期15卷 265-276页

作者： Guoping Chen Qiong Cai Wenjing fang Yuhao Feng Jiangling Zhu Chengjun Ji Zhiyao Tang jingyun fang Institute of Ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871China

落叶栎林是中国温带地区和亚热带山地典型的植被类型之一。虽然已有大量关于中国落叶栎林的群落结构特征研究,但以往研究多局限于局域尺度或单个类群,而在国家尺度上的系统性研究较为缺乏。本文采用统一的调查方法获取682个天然落叶栎... 详细信息

落叶栎林是中国温带地区和亚热带山地典型的植被类型之一。虽然已有大量关于中国落叶栎林的群落结构特征研究,但以往研究多局限于局域尺度或单个类群,而在国家尺度上的系统性研究较为缺乏。本文采用统一的调查方法获取682个天然落叶栎林样方数据,基于此数据分析了我国落叶栎林的群落结构特征及其空间格局,探究了影响其特征的气候和人为因素。研究结果表明,中国落叶栎林乔木层的平均胸径、平均树高、平均林分密度和平均总胸高断面积分别为:13.7 cm、10.0 m、1468株/ha和24.3 m^(2)/ha。落叶栎林乔木层、灌木层和草本层的平均物种丰富度分别为:6种/600 m^(2)、10种/100 m^(2)和4种/1 m^(2)。随纬度的升高,落叶栎林平均树高、林分密度、总胸高断面积、乔木层物种丰富度和灌木层物种丰富度均呈现显著降低趋势,林分平均胸径无显著变化,而草本层物种丰富度呈现显著增加趋势。进一步分析发现,相比于林分密度和草本层物种丰富度,气候和人类活动可以更多地解释平均胸径、平均树高、总胸高断面积、乔木层物种丰富度和灌木层物种丰富度的空间分异。此外,与降水相关的气候因子在塑造群落结构特征的空间格局方面起着更为重要的作用。总之,本研究为认识中国落叶栎林群落结构特征的生物地理格局及其对全球变化的响应提供了基础。

关键词：栎属(Quercus) 落叶栎林结构特征气候人类活动

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