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Carbon storage in a wolfberry plantation chronosequence established on a secondary saline land in an arid irrigated area of Gansu Province,China

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Journal of Arid Land 2018年第2期10卷 202-216页

作者： MA Quanlin WANG Yaolin LI Yinke SUN Tao Eleanor MILNE State Key Laboratory of Desertification and Aeolian Sand Disaster Combating Gansu Desert Control Research InstituteLanzhou 730070China Natural Resource ecology Laboratory Colorado State UniversityFort Collins CO 80523-1499USA

Carbon（C） storage has received significant attention for its relevance to agricultural security and climate change. Afforestation can increase C storage in terrestrial ecosystems, and has been recognized as an important measure to offset CO_2 emissions. In order to analyze the C benefits of planting wolfberry（Lycium barbarum L.） on the secondary saline lands in arid areas, we conducted a case study on the dynamics of biomass carbon（BC） storage and soil organic carbon（SOC） storage in different-aged wolfberry plantations（4-, 7-and 11-year-old） established on a secondary saline land as well as on the influence of wolfberry plantations on C storage in the plant-soil system in an arid irrigated area（Jingtai County） of Gansu Province, China. The C sequestration and its potential in the wolfberry plantations of Gansu Province were also evaluated. An intact secondary saline land was selected as control. Results show that wolfberry planting could decrease soil salinity, and increase BC, SOC and litter C storage of the secondary saline land significantly, especially in the first 4 years after planting. The aboveground and belowground BC storage values in the intact secondary saline land（control） accounted for only 1.0% and 1.2% of those in the wolfberry plantations, respectively. Compared to the intact secondary saline land, the SOC storage values in the 4-, 7-and 11-year-old wolfberry plantations increased by 36.4%, 37.3% and 43.3%, respectively, and the SOC storage in the wolfberry plantations occupied more than 92% of the ecosystem C storage. The average BC and SOC sequestration rates of the wolfberry plantations for the age group of 0–11 years were 0.73 and 3.30 Mg C/（hm^2·a）, respectively. There were no significant difference in BC and SOC storage between the 7-year-old and 11-year-old wolfberry plantations, which may be due in part to the large amounts of C offtakes in new branches and fruits. In Gansu Province, the C storage in the wolfberry plantations has reached up

关键词： Lycium barbaum biomass carbon soil organic carbon carbon sequestration potential secondary saline land wolfberry plantation carbon dynamics

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湖泊沉积植物古DNA的现代过程

植物生态学报 2022年第7期46卷 735-752页

作者：吴铠李凯贾伟瀚廖梦娜倪健浙江师范大学化学与生命科学学院浙江金华321004 Polar terrestrial Environmental Systems research group Alfred Wegener Institute Helmholtz Centre for Polar and Marine ResearchPotsdam 14473Germany Institute of Environmental Science and Geography University of PotsdamPotsdam 14476Germany

对植被历史变化过程的研究是理解现代植被组成、分布及其对全球变化响应的基础。近年来,随着分子古生态学的发展,分析沉积介质中的陆生植物古DNA信号,以研究植被及植物多样性演变的历史过程正在成为研究热点,湖泊沉积植物古DNA已成为古... 详细信息

对植被历史变化过程的研究是理解现代植被组成、分布及其对全球变化响应的基础。近年来,随着分子古生态学的发展,分析沉积介质中的陆生植物古DNA信号,以研究植被及植物多样性演变的历史过程正在成为研究热点,湖泊沉积植物古DNA已成为古植被和古生态学研究的成熟代用指标。然而与第四纪孢粉分析相比较,湖泊沉积植物古DNA的现代过程依然不明确,成为其进一步发展和应用的限制因素。基于此,该文综述了湖泊沉积植物古DNA技术研究进展,尝试阐明湖泊沉积植物古DNA的现代过程,包括植物DNA的来源、沉积和保存过程及其影响因素,以及植物DNA与现代植被的关系等。已有研究表明,湖泊沉积植物古DNA主要来自湖泊周边或流域范围,其丰度和组成除受到源植物生物量的影响外,同样受到沉积物的搬运和沉积过程中DNA降解作用、土壤以及沉积物中颗粒的吸附过程和稀释作用等因素的影响。湖泊沉积物中植物DNA的保存则主要受到微生物活动、湖水的化学性质(电导率和pH值)、湖泊深度、沉积物组成等一系列生物与非生物因素的共同影响。湖泊沉积植物古DNA可以揭示其沉积时代的植物群落类型以及气候环境信息,但目前并不能够用来定量重建古植被变化过程。鉴于湖泊沉积植物古DNA现代过程的复杂性,对研究结果的解释要格外小心。与孢粉分析相比,湖泊沉积植物古DNA研究仍处于起步阶段,但随着分子生物技术的进步、实验设计的优化、物种条形码的扩充及参考数据库的完善等,以DNA宏条形码和宏基因组学为主要技术手段的植物古DNA技术,必将推动我国植物古生态研究的进一步发展。

关键词：湖泊沉积植物古DNA 埋藏学植被代表性古植被古生态学

Spatiotemporal variation of land surface temperature and its driving factors in Xinjiang,China

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Journal of Arid Land 2024年第3期16卷 373-395页

作者： ZHANG Mingyu CAO Yu ZHANG Zhengyong ZHANG Xueying LIU Lin CHEN Hongjin GAO Yu YU Fengchen LIU Xinyi College of Sciences Shihezi UniversityShihezi 832000China Key Laboratory of Oasis Town and Mountain-Basin System ecology Xinjiang Production and Construction CorpsShihezi 832000China Yantai Institute of Coastal Zone research Chinese Academy of SciencesYantai 264003China

Land surface temperature(LST) directly affects the energy balance of terrestrial surface systems and impacts regional resources, ecosystem evolution, and ecosystem structures. Xinjiang Uygur Autonomous Region is located at the arid Northwest China and is extremely sensitive to climate change. There is an urgent need to understand the distribution patterns of LST in this area and quantitatively measure the nature and intensity of the impacts of the major driving factors from a spatial perspective, as well as elucidate the formation mechanisms. In this study, we used the MOD11C3 LST product developed on the basis of Moderate Resolution Imaging Spectroradiometer(MODIS) to conduct regression analysis and determine the spatiotemporal variation and differentiation pattern of LST in Xinjiang from 2000 to 2020. We analyzed the driving mechanisms of spatial heterogeneity of LST in Xinjiang and the six geomorphic zones(the Altay Mountains, Junggar Basin, Tianshan Mountains, Tarim Basin, Turpan-Hami(Tuha) Basin, and Pakakuna Mountain group) using geographical detector(Geodetector) and geographically weighted regression(GWR) models. The warming rate of LST in Xinjiang during the study period was 0.24℃/10a, and the spatial distribution pattern of LST had obvious topographic imprints, with 87.20% of the warming zone located in the Gobi desert and areas with frequent human activities, and the cooling zone mainly located in the mountainous areas. The seasonal LST in Xinjiang was at a cooling rate of 0.09℃/10a in autumn, and showed a warming trend in other seasons. Digital elevation model(DEM), latitude, wind speed, precipitation, normalized difference vegetation index(NDVI), and sunshine duration in the single-factor and interactive detections were the key factors driving the LST changes. The direction and intensity of each major driving factor on the spatial variations of LST in the study area were heterogeneous. The negative feedback effect of DEM on the spatial differentiation o

关键词： land surface temperature MOD11C3 climate change geographical detector(Geodetector) geographically weighted regression(GWR) source-sink effect Xinjiang

Contributions of natural systems and human activity to greenhouse gas emissions

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Advances in Climate Change research 2018年第4期9卷 243-252页

作者： YUE Xi-Liu GAO Qing-Xian China Reinsurance (group) Corporation Post-doctoral Workstation Beijing 100033 China Beijing Normal University Beijing 100875 China Chinese research Academy of Environmental Sciences Beijing 100012 China

In this study, we conducted a literature review of relevant research and then statistically analyzed global greenhouse gas (GHG) emissions from natural systems, including forest fires, oceans, wetlands, permafrost, mud volcanoes, volcanoes, and earthquakes. Drawing on the Global Carbon Project (GCP) report, we also summarized the global anthropogenic GHG emissions. We then compared the global annual GHG emissions from natural systems with those generated by human activity. The results indicate that the global annual GHG emissions range approximately between 54.33 and 75.50 Gt CO2-eq, of which natural emissions account for 18.13e39.30 Gt CO2-eq, with the most likely value being approximately 29.07 Gt CO2-eq. According to the GCP report, the global anthropogenic emissions have increased from 22 Gt CO2-eq in 1990 to 36.2 Gt CO2-eq in 2016. The amounts of natural and anthropogenic GHGs emissions are roughly of the same order of magnitude. Anthropogenic emissions account for approximately 55.46% of the total global GHGs emissions (2016 value), i.e., the ratio of natural to anthropogenic emissions is approximately 0.8. In addition, the annual amount of GHGs absorbed by Earth systems (ocean and terrestrial ecosystems) ranges between approximately 14.4 Gt CO2-eq and 26.5 Gt CO2-eq, with natural system GHG emissions and sinks also having roughly the same order of magnitude. This finding indicates that the GHG emissions generated by human activity exert extra pressure on what is otherwise a self-balancing Earth system.

关键词： Greenhouse gases Natural emission Anthropogenic emission Global emission Natural system

Modelling impacts of acid deposition and groundwater level on habitat quality and plant species diversity

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Ecological Processes 2016年第1期5卷 273-291页

作者： J.Kros J.P.Mol-Dijkstra G.W.W.Wamelink G.J.Reinds Avan Hinsberg W.de Vries Wageningen Environmental research Wageningen University and ResearchP.O.Box 476700 AA WageningenThe Netherlands Netherlands Environmental Assessment Agency PO Box 3033720 BABilthovenWageningenThe Netherlands Environmental Systems Analysis group Wageningen University and ResearchP.O.Box 476700 AA WageningenThe Netherlands

Introduction:We quantified the effects of the site factors pH and nitrate(NO_(3))concentration in soil solution and groundwater level on the vegetation of terrestrial ecosystems for the Netherlands in response to changes in atmospheric nitrogen(N)and sulphur(S)deposition and groundwater level over the period *** assessment was made with the SMART2 model,a simple one-layer model including geochemical buffer processes,element cycling by litterfall,mineralisation and uptake,nitrogen transformation processes and element input through deposition,weathering and upward ***:To assess the effects of changes in abiotic site factors on the vegetation,we developed a simple plant diversity indicator for grassland,heathland and forest,based on the occurrence of target plant species and competing *** occurrence was calculated from the preferred ranges of each species for the NO_(3) concentration and pH in soil solution and mean spring groundwater *** in the plant diversity indicator were assessed from effects of changes in the occurrence of target and competing plant species in response to changes in mean spring groundwater level and in pH and NO_(3) concentration,as calculated with *** were made for combinations of five vegetation structure types(three forest types,semi-natural grassland and heathland)and seven soil types(three sandy soils,two clay soils,peat and loess soils)using a 250×250 m *** used data for atmospheric deposition and groundwater level in the past to assess trends between 1990 and 2010 and evaluated two future scenarios for the period 2010-2030:a Business as Usual and an Improved Environment ***:Comparison of model predictions on pH and NO_(3) with measured soil solution concentrations for forest showed a reasonable to good agreement for pH but rather poor for NO_(3).The largest impacts were found for the combination of the two Improved Environment ***:Reductions in N

关键词： Nutrient cycling Soil modelling Biodiversity Acidification Scenario analysis

Testing optically stimulated luminescence dating on sand-sized quartz of deltaic deposits from the Sperchios delta plain, central Greece

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Journal of Palaeogeography 2018年第2期7卷 130-145页

作者： Evangelos Tsakalos Elias Dimitriou Maria Kazantzaki Christos Anagnostou John Christodoulakis Eleni Filippaki Hellenic Centre for Marine research Institute of Inland Waters Laboratory of Archaeometry Institute of Nanoscience and Nanotechnology National Centre for Scientific Research N.C.S.R. "Demokritos" Department of Geophysics Division of Earth and Planetary Sciences Graduate School of Science Kyoto University Hellenic Centre of Marine research Institute of Oceanography Climate research group Division of Environmental Physics and Meteorology Faculty of Physics National and Kapodistrian University of Athens

This study reports on the first investigation into the potential of luminescence dating to establish a chronological framework for the depositional sequences of the Sperchios delta plain, central Greece. A series of three borehole cores(20 m deep) and two shallow cores(4 m deep), from across the delta plain, were extracted, and samples were collected for luminescence dating. The luminescence ages of sand-sized quartz grains were obtained from small aliquots of quartz, using the Single-Aliquot Regenerative-dose(SAR) *** equivalent dose determination included a series of tests and the selection of the Minimum Age Model(MAM) as the most appropriate statistical model. This made it possible to confirm the applicability of quartz Optically Stimulated Luminescence(OSL) dating to establish absolute chronology for deltaic sediments from the Sperchios delta *** age results of the five cores showed that the deltaic sediments were deposited during the Holocene.A relatively rapid deposition is implied for the top14 m possibly as a result of the deceleration in the rate of the sea-level rise and the transition to terrestrial conditions, while on the deeper parts, the reduced sedimentation rate may indicate a lagoonal or coastal environment.

关键词： Luminescence dating Holocene Sedimentation rates Deltaic deposits Sperchios delta plain Central Greece

National Forest Inventories capture the multifunctionality of managed forests in Germany

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Forest Ecosystems 2021年第1期8卷 50-68页

作者： Nadja K.Simons María R.Felipe-Lucia Peter Schall Christian Ammer Jürgen Bauhus Nico Blüthgen Steffen Boch François Buscot Markus Fischer Kezia Goldmann Martin M.Gossner Falk Hänsel Kirsten Jung Peter Manning Thomas Nauss Yvonne Oelmann Rodica Pena Andrea Polle Swen C.Renner Michael Schloter Ingo Schöning Ernst-Detlef Schulze Emily F.Solly Elisabeth Sorkau Barbara Stempfhuber Tesfaye Wubet Jörg Müller Sebastian Seibold Wolfgang W.Weisser terrestrial ecology research group Technische Universität MünchenHans-Carl-von-Carlowitz-Platz 285354 FreisingGermany Present address:Ecological Networks Technische Universität DarmstadtSchnittspahnstraße 364287 DarmstadtGermany Helmholtz Centre for Environmental research-UFZ Department of Ecosystem ServicesDeutscher Platz 5e04103 LeipzigGermany Present address:German Centre for Integrative Biodiversity research(iDiv)Halle-Jena-Leipzig Deutscher Platz 5e04103 LeipzigGermany Silviculture and Forest ecology of the Temperate Zones University of GöttingenBüsgenweg 137077 GöttingenGermany Centre for Biodiversity and Sustainable Land-use University of GöttingenBüsgenweg 137073 GöttingenGermany Chair of Silviculture Faculty of Environment and Natural ResourcesUniversity of FreiburgTennenbacherstr.479106 FreiburgGermany Ecological Networks Technische Universität DarmstadtSchnittspahnstraße 364287 DarmstadtGermany Institute of Plant Sciences University of BernAltenbergrain 213013 BernSwitzerland Biodiversity and Conservation Biology WSL Swiss Federal Research InstituteZürcherstrasse 1118903 BirmensdorfSwitzerland Helmholtz Centre for Environmental research-UFZ Department of Soil EcologyTheodor-Lieser-Straße 406120 Halle(Saale)Germany German Centre for Integrative Biodiversity research(iDiv)Halle-Jena-Leipzig Deutscher Platz 5e04103 LeipzigGermany Forest Entomology WSL Swiss Federal Research InstituteZürcherstrasse 1118903 BirmensdorfSwitzerland Department of Environmental Systems Science Institute of Terrestrial EcosystemsETH ZürichUniversitätstr 168092 ZürichSwitzerland Environmental Informatics University of MarburgDeutschhausstraße 1235032 MarburgGermany Evolutionary ecology and Conservation Genomics Ulm UniversityAlbert-Einstein-Allee 1189069 UlmGermany Senckenberg Biodiversity and Climate research Centre Senckenberganlage 2560325 Frankfurt am MainGermany Geoecology University of TübingenRümelinstraße 19-2372070 TübingenGermany Present address:Department of Sustaina

Background:Forests perform various important ecosystem functions that contribute to ecosystem *** many parts of the world,forest management has shifted from a focus on timber production to multi-purpose forestry,combining timber production with the supply of other forest ecosystem ***,it is unclear which forest types provide which ecosystem services and to what extent forests primarily managed for timber already supply multiple ecosystem *** on a comprehensive dataset collected across 150 forest plots in three regions differing in management intensity and species composition,we develop models to predict the potential supply of 13 ecosystem *** use those models to assess the level of multifunctionality of managed forests at the national level using national forest inventory ***:Looking at the potential supply of ecosystem services,we found trade-offs(*** both bark beetle control or dung decomposition and both productivity or soil carbon stocks)as well as synergies(*** temperature regulation,carbon storage and culturally interesting plants)across the 53 most dominant forest types in *** single forest type provided all ecosystem services *** ecosystem services showed comparable levels across forest types(*** or richness of saprotrophs),while others varied strongly,depending on forest structural attributes(*** availability or cover of edible plants)or tree species composition(*** nitrification activity).Variability in potential supply of ecosystem services was only to a lesser extent driven by environmental ***,the geographic variation in ecosystem function supply across Germany was closely linked with the distribution of main tree ***:Our results show that forest multifunctionality is limited to subsets of ecosystem *** importance of tree species composition highlights that a lack of multifunctionality at the stand lev

关键词： Ecosystem processes and services Forest management Structural diversity Tree species composition Trade-offs and synergies Forest productivity

Source,depositional environment and maturity levels of some crude oils in southwest Niger Delta,Nigeria

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Chinese Journal Of Geochemistry 2015年第2期34卷 224-232页

作者： Mudiaga Chukunedum Onojake L.C.Osuji S.Abrakasa Petroleum Chemistry research group Department of Pure and Industrial ChemistryUniversity of Port Harcourt Centre for Petroleum Geosciences Institute of Petroleum StudiesUniversity of Port Harcourt Department of Petroleum Engineering Niger Delta University

A suite of crude oil samples,that had not been previously characterized geochemically,was collected from two oil fields in the southwest Niger Delta *** saturate biomarkers were used to evaluate geochemical characteristics such as depositional environments,sources of organic matter and extent of biodegradation using gas chromatography-flame ionization detector and gas chromatography-mass *** of n-alkanes(Pr/Ph,and isoprenoide/n-alkanes ratios),the abundance of hopanes,oleanane skeleton and C27-C29 steranes in the oils indicate that they were formed from mixed sources(marine and terrestrial kerogen) deposited in an oxic paleoenvironment with no particular maturity *** parameters also permit the source grouping of the oils into two families.

关键词：尼日尔三角洲尼日利亚沉积环境西南部成熟度三角洲地区原油地球化学特征

Alterations of soil aggregates and intra-aggregate organic carbon fractions after soil conversion from paddy soils to upland soils:Distribution,mineralization and driving mechanism

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Pedosphere 2024年第1期34卷 121-135页

作者： Longfei KANG Jiamei WU Chunfeng ZHANG Baoguo ZHU Guixin CHU College of Life Science Shaoxing UniversityShaoxing 312000China The Key Laboratory of Oasis Eco-agriculture Xinjiang Production and Construction Group/Department of Resources and Environmental SciencesAgronomy CollegeShihezi UniversityShihezi 832000China Hunan Institute of Agricultural Environment and ecology Changsha 410000China Jiamusi Branch Heilongjiang Academy of Agricultural SciencesJiamusi 154007China

Investigating the impacts of soil conversion on soil organic carbon(OC) content and its fractions within soil aggregates is essential for defining better strategies to improve soil structure and OC sequestration in terrestrial ecosystems. However, the consequences of soil conversion from paddy soil to upland soil for soil aggregates and intra-aggregate OC pools are poorly understood. Therefore, the objective of this study was to quantify the effects of soil conversion on soil aggregate and intra-aggregate OC pool distributions. Four typical rice-producing areas were chosen in North and South China, paired soil samples(upland soil converted from paddy soil more than ten years ago vs. adjacent paddy soil) were collected(0–20 cm) with three replicates in each area. A set of core parameters(OC preservation capacity, aggregate carbon(C) turnover, and biological activity index) were evaluated to assess the responses of intra-aggregate OC turnover to soil conversion. Results showed that soil conversion from paddy soil to upland soil significantly improved the formation of macro-aggregates and increased aggregate stability. It also notably decreased soil intra-aggregate OC pools, including easily oxidized OCa(EOCa), particulate OCa(POCa), and mineral-bound(MOCa) OC, and the sensitivity of aggregate-associated OC pools to soil conversion followed the order: EOCa(average reduction of 21.1%) > MOCa(average reduction of 15.4%) > POCa(average reduction of 14.8%). The potentially mineralizable C(C_(0)) was significantly higher in upland soil than in paddy soil, but the corresponding decay constant(k) was lower in upland soil than in paddy soil. Random forest model and partial correlation analysis showed that EOCa and pH were the important nutrient and physicochemical factors impacting k of C mineralization in paddy soil,while MOCa and C-related enzyme(β-D-cellobiohydrolase) were identified as the key factors in upland soil. In conclusion, this study evidenced that soil conversion

关键词： decay constant easily oxidized organic C macro-aggregate meso-aggregate micro-aggregate mineral-bound organic C particulate organic C potentially mineralizable C