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Nitrogen addition promotes soil carbon accumulation globally

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Science China Life Sciences 2025年第1期 284-293页

作者： Xuemei Yang Suhui Ma Erhan Huang Danhua Zhang Guoping Chen Jiangling Zhu Chengjun Ji Biao Zhu Lingli Liu Jingyun Fang Institute of ecology College of Urban and Environmental Sciencesand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking University Ministry of Education Key Laboratory for Transboundary Ecosecurity of Southwest China School of Ecology and Environmental ScienceYunnan University State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of Sciences

Soil is the largest carbon(C) reservoir in terrestrial ecosystems and plays a crucial role in regulating the global C cycle and climate *** nitrogen(N) deposition has been widely considered as a critical factor affecting soil organic carbon(SOC) storage, but its effect on SOC components with different stability remains unclear. Here, we analyzed extensive empirical data from 304 sites worldwide to investigate how SOC and its components respond to N addition. Our analysis showed that N addition led to a significant increase in bulk SOC(6.7%), with greater increases in croplands(10.6%) and forests(6.0%) compared to grasslands(2.1%). Regarding SOC components, N addition promoted the accumulation of plant-derived C(9.7%–28.5%) over microbial-derived C(0.2%), as well as labile(5.7%) over recalcitrant components(–1.2%), resulting in a shift towards increased accumulation of plant-derived labile C. Consistently, N addition led to a greater increase in particulate organic C(11.9%) than mineral-associated organic C(3.6%), suggesting that N addition promotes C accumulation across all pools, with more increase in unstable than stable pools. The responses of SOC and its components were best predicted by the N addition rate and net primary productivity. Overall, our findings suggest that N enrichment could promote the accumulation of plant-derived and non-mineral associated C and a subsequent decrease in the overall stability of soil C pool, which underscores the importance of considering the effects of N enrichment on SOC components for a better understanding of C dynamics in soils.

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Improved data gap-filling schemes for estimation of net ecosystem exchange in typical East-Asian croplands

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Science China Earth Sciences 2016年第8期59卷 1652-1664页

作者： ZHAO Peng Johannes LüERS Department of Micrometeorology University of Bayreuth Institute of ecology University of Innsbruck Member of Bayreuth center of ecology and Environmental research (BayCEER) University of Bayreuth

The estimation of carbon exchange between ecosystems and the atmosphere suffers unavoidable data gaps in eddy-covariance technique, especially for short-living and fast-growing croplands. In this study we developed a modified gap-filling scheme introducing a leaf area index factor as the vegetation status information based on the conventional light response function for two East-Asian cropland sites (rice and potatoes). This scheme’s performance is comparable to the conventional time window scheme, but has the advantage when the gaps are large compared to the total length of the time series. To investigate how the time binning approach performs for fast-growing croplands, we tested different widths of the time window, showing that a four-day window for the potato field and an eight-day time window for the rice field perform the best. The insufficiency of the conventional temperature binning approach was explained as well as the influence of vapor pressure deficit. We found that vapor pressure deficit plays a minor role in both the potato and the rice fields under Asian monsoon weather conditions with the exception of the early pre-monsoon growing stage of the potatoes. Consequently, we recommend using the conventional time-window scheme together with our new leaf-light response function to fill data gaps of net ecosystem exchange in fast-growing croplands.

关键词： Eddy-covariance Gap-filling Net ecosystem exchange LAI

Genitalia-associated microbes in insects

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Insect Science 2015年第3期22卷 325-339页

作者： Oliver Otti Animal Population ecology Animal Ecology I Bayreuth Center of Ecology and Environmental Research (BayCEER) University of Bayreuth Universitatsstrasse 30 95440 Bayreuth Germany

In sexual reproduction different types of symbiotic relationships between insects and microbes have become established. For example, some bacteria have evolved almost exclusive vertical transmission and even define the compatibility of insect mating partners. Many strictly sexually transmitted diseases have also been described in insects. Apart from such rather specific relationships the role of opportunistic infections in the reproductive process has been widely neglected. Opportunistic microbes transmitted passively during mating might impose an energetic cost, as the immune system will need to be alert and will use resources to fight potential intruders. Through mating wounds and contaminated reproductive organs opportunistic microbes might be transferred to mating partners and even enter the body cavity. Females as the ＂receiving＂ sex are particularly likely to have evolved adaptations to avoid or reduce opportunistic infections. Males of several species show highly complex seminal fluids, which as well as containing components that influence a males＇ fertilization success, also possess antimicrobial substances. The role of antimicrobials in the reproductive process is not well understood. Some evidence hints at the protection of sperm against microbes, indicating a role for natural selection in shaping the evolution of reproductive traits. By highlighting the potential importance of microbes in sexual selection and their role in reproduction in general I will make a case for studies in sexual selection, especially the ones investigating postcopulatory processes, that should incorporate environmental, as well as genotypic variation, in reproductive traits.

关键词： genital microbiome interactions sexually transmitted microbes spermmicrobe

Do microsporidia function as ＂biological weapon＂ for Harmonia axyridis under natural conditions？

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Insect Science 2015年第3期22卷 353-359页

作者： Tobias Gegner Oliver Otti Simon Tragust Heike Feldhaar Animal Population ecology Department of Animal Ecology I Bayreuth Center of Ecology and Environmental Research (BayCEER) University of Bayreuth D-95440 Bayreuth Germany

Invasive alien species, such as the multicoloured Asian ladybird Harmonia axyridis, are often regarded as major drivers ofbiodiversity loss. Therefore understanding which characteristics or mechanisms contribute to their invasive success is important. Here the role of symbiotic microsporidia in the hemolymph of H. axyridis was investigated in the context of intraguild predation between wild-caught H. axyridis and the native ladybird species Coccinella septempunctata. The microsporidia were recently discussed to contribute to the unpalatability of Harmonia for other coccinellids during intraguild predation and to function as ＂biological weapons＂. In the present study, visual detection of microsporidia in hemolymph samples revealed that 73.5 % of H. axyridis were infected. Intraguild predation experiments between larvae of the two species showed a significant competitive advantage for H. axyridis, even against larger larvae of C. septempunctata. Adult C. septempunctata always killed and fed on H. axyridis larvae. However only 11.4 % （4 of 47） of C. septempunctata that fed on infected H. axyridis died within 4 months. In contrast to previous studies this suggests that microsporidia or harmonine, the chemical defense compound of H. axyridis, do not lead to death of C. septempunctata preying on larvae ofH. axyridis. Instead our results support the idea that competitive advantage during intraguild predation greatly facilitates the success of H. axyridis and that this may help this highly invasive species to outcompete native species. The impact of microsporidia on Harmonia itself as well as on interspecific interactions require further studies.

关键词： defensive symbiont endosymbiont Harmonia axyridis invasive species microsporidia

Diet and feeding ecology of invasive icefish Neosalanx taihuensis in Erhai Lake,a Chinese plateau mesoeutrophicated lake

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Chinese Journal of Oceanology and Limnology 2015年第2期33卷 372-380页

作者：胡翠林过龙根王圣瑞 Fisheries College Huazhong Agricultural University Donghu Experimental Station of Lake Ecosystems State Key Laboratory of Freshwater Ecology and Biotechnology of ChinaInstitute of HydrobiologyChinese Academy of Sciences research center of Lake Environment Chinese Research Academy of Environment Sciences

A comprehensive study of the invasive icefish Neosalanx taihuensis feeding ecology in Erhai Lake was conducted from November 2009 to October 2010. Prey items in the guts of the icefish sampled varied significantly according to season. This finding suggests a relationship between fluctuations in available prey in the environment and selective feeding by icefish. N. taihuensis preferred large-sized zooplankton, such as Daphnia and calanoids. Additionally, the gut fullness values differed significantly （P〈0.001） among sampling times. To compare the values at different times, samples were taken over a 24 h period every 2 months for the entire year. The feeding activities of the fish were concentrated either in the morning （8：00） and/or at dusk （20：00）, except in September 2010. This finding can be explained primarily by the variation in optimum light intensity. Daily N. taihuensis zooplankton consumption varied significantly, both diurnally and among seasons. The daily consumption values ranged from 0.089 to 0.237 g （wet weight） per 100 g wet fish weight in temperatures between 11.50℃ and 24.68℃. This is the first report of diel feeding periodicity and daily food consumption of icefish in their invaded ecosystems.

关键词： dietary composition crustacean zooplankton feeding ecology invasive species Neosalanxtaihuensis

Dominance of rock exposure and soil depth in leaf trait networks outweighs soil quality in karst limestone and dolomite habitats

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Forest Ecosystems 2024年第5期11卷 632-641页

作者： Min Jiao Jiawei Yan Ying Zhao Tingting Xia Kaiping Shen Yuejun He Forestry College Research Center of Forest EcologyGuizhou UniversityGuiyang550025China

Leaf trait networks(LTNs)visualize the intricate linkages reflecting plant trait-functional *** karst vegetation,developed from lithological dolomite and limestone,generally exhibits differential communities,possibly due to habitat rock exposure,soil depth,and soil physicochemical properties variations,leading to a shift from plant trait variation to functional ***,how soil and habitat quality affect the differentiation of leaf trait networks remains *** were constructed for typical dolomite and limestone habitats by analyzing twenty-one woody plant leaf traits across fifty-six forest subplots in karst *** differences between dolomite and limestone LTNs were compared using network *** network association of soil and habitat quality was analyzed using redundancy analysis(RDA),Mantle's test,and a random forest *** limestone LTN exhibited significantly higher edge density with lower diameter and average path length when compared to the dolomite *** indicates LTN differentiation,with the limestone network displaying a more compact architecture and higher connectivity than the dolomite *** specific leaf phosphorus and leaf nitrogen contents of dolomite LTN,as well as the leaf mass and leaf carbon contents of limestone LTN,significantly contributed to network degree and closeness,serving as crucial node traits regulating LTN ***,both habitat LTNs significantly correlated with soil nitrogen and phosphorus,stoichiometric ratios,pH,and organic carbon,as well as soil depth and rock exposure rates,with soil depth and rock exposure showing greater relative *** depth and rock exposure dominate trait network differentiation,with the limestone habitat exhibiting a more compact network architecture than the dolomite habitat.

关键词： Leaf trait networks Functional traits Woody plant community Karst Dolomite Limestone

Botanic gardens should lead the way to create a "Garden Earth" in the Anthropocene

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Plant Diversity 2017年第6期39卷 331-337页

作者： Charles H.Cannon Chai-Shian Kua The center for Tree Science The Morton Arboretum Science and Conservation The Morton Arboretum Shanghai Engineering research center for Urban Tree ecology and Applications

The strength and expertise that botanic gardens bring to conservation are based on their detailed knowledge and understanding of the care. management, and biology of a diversity of plant species. This emphasis on the organism has led to many ex-situ and in-situ conservation programs aimed at protecting endangered species, restoring threatened populations, and establishing living plant and seed collections of endangered species. In China, the scale and pace of change in land and resource use, often leading to environmental degradation, has created a strong emphasis on improving environmental conditions. If done properly, being "green" can be a surprisingly complex issue, because it should encompass and exploit the whole of plant diversity and function. Unfortunately, 'green' often includes a small portion of this whole. Earth's rich plant diversity presents considerable opportunity but requires expertise and knowledge for stable and beneficial management. With the dawning of the Anthropocene, we should strive to live on a "Garden Earth", where we design and manage our environments, both built and natural, to create a healthy, beneficial living landscape for people and other organisms. The staff of botanic gardens worldwide and the living collections they maintain embody the best examples of sustainable, beautiful, and beneficial environments that thrive on plant diversity. This expertise should be a fundamental resource for agencies in all sectors responsible for managing and designing "green" infrastructure. Botanic gardens should actively engage and contribute to these opportunities, from large public infrastructure projects to small private conservation efforts. Here, we discuss several ongoing conservation efforts, primarily in China, and attempt to identify areas where botanic gardens could make a significant and meaningful difference.

关键词： Green infrastructure Botanic garden Ex-situ conservationln-situ conservation Botanical garden

Urban and rural transport of semivolatile organic compounds at regional scale: A multimedia model approach

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Journal of Environmental Sciences 2016年第1期28卷 228-241页

作者： Shuai Song Chao Su Yonglong Lu Tieyu Wang Yueqing Zhang Shijie Liu State Key Laboratory of Urban and Regional ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Urban areas are generally regarded as major sources of some semivolatile organic compounds and other persistent organic pollutants（POPs） to the surrounding regions. Huge differences in contaminant emissions between urban and rural areas directly affect their fate in environmental media. Little is known about POPs behavior between urban and rural areas at a regional scale. A spatially resolved Berkeley-Trent-Urban-Rural Fate Model（BETR-UR） was designed by coupling land cover information to simulate the transport of POPs between urban and rural areas, and the Bohai Rim was used as a case study to estimate Polycyclic Aromatic Hydrocarbon（PAH） fate. The processes of contaminant fate including emission, inter-compartmental transfer, advection and degradation in urban and rural areas were simulated in the model. Simulated PAH concentrations in environmental media of urban and rural areas were very close to measured values. The model accuracy was highly improved, with the average absolute relative error for PAH concentrations reduced from 37% to 3% compared with unimproved model results. PAH concentrations in urban soil and air were considerably higher than those in rural areas. Sensitivity analysis showed temperature was the most influential parameter for Phen rather than for Bap, whose fate was more influenced by emission rate, compartment dimension, transport velocity and chemical persistence. Uncertainty analysis indicated modeled results in urban media had higher uncertainty than those in rural areas due to larger variations of emissions in urban areas. The differences in urban and rural areas provided us with valuable guidance on policy setting for urban–rural POP control.

关键词： Land use PAH fate Regional scale Multimedia model

Dynamic analysis and assessment for sustainable development

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Journal of Environmental Sciences 2002年第1期14卷 88-94页

作者： SHI Xiao\|qing (Department of Systems ecology, research center for Eco\|Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. ) Department of Systems ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The assessment of sustainable development is crucial for constituting sustainable development strategies. Assessment methods that exist so far usually only use an indicator system for making sustainable judgement. These indicators rarely reflect dynamic characteristics. However, sustainable development is influenced by changes in the social\|economic system and in the eco\|environmental system at different times. Besides the spatial character, sustainable development has a temporal character that can not be neglected; therefore the research system should also be dynamic. This paper focuses on this dynamic trait, so that the assessment results obtained provide more information for judgements in decision\|making processes. Firstly the dynamic characteristics of sustainable development are analyzed, which point to a track of sustainable development that is an upward undulating curve. According to the dynamic character and the development rules of a social, economic and ecological system, a flexible assessment approach that is based on tendency analysis, restrictive conditions and a feedback system is then proposed for sustainable development.

关键词： sustainable development assessment dynamic analysis