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Responses of plant community to the linkages in plant-soil C:N:P stoichiometry during secondary succession of abandoned farmlands,China

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Journal of Arid Land 2020年第2期12卷 215-226页

作者： LIU Weichao FU Shuyue YAN Shengji ren chengjie WU Shaojun DENG Jian LI Boyong HAN Xinhui YANG Gaihe College of Agronomy Northwest A&F UniversityYangling 712100China Research Center of Recycle Agricultural Engineering and Technology of Shaanxi Province Yangling 712100China School of Life Science Yan'an UniversityYan'an 716000China

Succession is one of the central themes of ecology;however,the relationship between aboveground plant communities and underground soils during secondary succession remains *** this study,we investigated the composition of plant community,plant-soil C:N:P stoichiometry and their relationships during secondary succession after the abandonment of farmlands for 0,10,20,30,40 and 50 a in China,*** showed that the composition of plant communities was most diverse in the farmlands after secondary succession for 20 and 50 *** organic carbon and total nitrogen contents slightly decreased after secondary succession for 30 a,but both were significantly higher than those of control farmland(31.21%-139.10%and 24.24%-121.21%,respectively).Moreover,C:N ratios of soil and microbe greatly contributed to the changes in plant community composition during secondary succession of abandoned farmlands,explaining 35.70%of the total ***,soil C:N ratio was significantly and positively related with the Shannon-Wiener *** study provides the evidence of synchronous evolution between plant community and soil during secondary succession and C:N ratio is an important linkage between them.

关键词： C:N ratio soil nutrient plant community restoration loess hilly region

N-cycle gene abundance determination of N mineralization rate following re-afforestation in the Loess Plateau of China

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Soil Ecology Letters 2024年第1期6卷 97-106页

作者： Yaping Zhao Yuqing Zhao Shuohong Zhang Yulin Xu Xinhui Han Gaihe Yang chengjie ren College of Agronomy Northwest A&F UniversityYangling 712100China Shaanxi Engineering Research Center of Circular Agriculture College of AgronomyNorthwest A&F UniversityYangling 712100China

Afforestation effectively improved soil microbial communities and significantly increased soil nitro-gen mineralization rate(Rm).Soil microorganisms drive Rm by regulating soil N-cycling *** nitrification genes had a major effect on soil Rm than denitrification genes after *** the function of forest ecosystems requires an understanding of the mechanism of soil nitrogen ***,it remains unclear how soil N-cycling genes drive soil nitrogen mineralization during *** this study,we collected soil samples from a chrono-sequence of 14,20,30,and 45 years of Robinia pseudoacacia L.(RP14,RP20,RP30,and RP45)with a sloped farmland(FL)as a *** metagenomic sequencing analysis,we found significant changes in the diversity and composition of soil microbial communities involved in N-cycling along the afforestation time series,with afforestation effectively increasing the diversity(both alpha and beta diversity)of soil microbial *** conducted indoor culture experiments and analyzed correlations,which revealed a significant increase in both soil nitrification rate(Rn)and soil nitrogen mineralization rate(Rm)with increasing stand ***,we found a strong correlation between soil Rm and soil microbial diversity(both alpha and beta diversity)and with the abundance of soil N-cycling *** least squares path modeling(PLS-PM)analysis showed that nitrification genes(narH,narY,nxrB,narG,narZ,nxrA,hao,pmoC-amoC)and denitrification genes(norB,nosZ,nirK)had a greater direct effect on soil Rm compared to their effect on soil microbial *** results reveal the relationships between soil nitrogen mineralization rate and soil microbial communities and between the mineralization rate and functional genes involved in N-cycling,in the context of Robinia pseudoacacia *** on the Loess *** study enriches the understanding of the effects of microorganisms on soil nitrogen mineraliza

关键词： afforestation soil N mineralization rate denitrification genes nitrification genes the Loess Plateau

Effect of Soil C,N and P Stoichiometry on Soil Organic C Fractions After Afforestation

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Pedosphere 2017年第4期27卷 705-713页

作者： ZHAO Fazhu ZHANG Lu SUN Jiao ren chengjie HAN Xinhui YANG Gaihe PANG Guowei BAI Hongying WANG Jun College of Urban and Environmental Sciences Northwest University Shaanxi Land Construction Group Shaanxi LCG Land Project Technology InstituteKey Laboratory of Degraded and Unused Land Consolidation Engineeringthe Ministry of Land and Resources of China Institute of Agricultural Resources and Environment Ningxia Academy of Agriculture and Forestry Sciences College of Agronomy Northwest A&F University

Afforestation is recognized as an important driving force for soil organic C(SOC) dynamics and soil element *** evaluate the relationships between soil C:N:P stoichiometry and SOC fractions,soil C:N:P stoichiometry distributions at 0–200 cm soil depths were analyzed and the contents of SOC fractions were evaluated in 9 typical land-use systems on the Loess Plateau of *** contents of light fraction organic C,particulate organic C(>53,53–2 000,and>2 000 μm),labile organic C,microbial biomass C,and dissolved organic C decreased with increasing soil depth and were higher in afforested soil than in slope cropland *** with the slope cropland,different vegetation types influenced soil C:N,C:P,and N:P ratios,especially when C:P and N:P ratios were significantly higher(Prent soil depths after afforestation.

关键词： dissolved organic C, labile organic C, light fraction organic C, microbial biomass C, particulate organic C

Unique genes carried by abundant species enhance CH_(4) emissions during the growing season at the Tibetan Plateau

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Soil Ecology Letters 2024年第2期6卷 83-95页

作者： Yue Liang Liyuan He Jieying Wang Yanfang Liu Wenying Wang chengjie ren Jun Wang Yaoxin Guo Ninglian Wang Fazhu Zhao Shaanxi Key Laboratory of Earth Surface System and Environmental Carrying Capacity Northwest UniversityXi’an710127China College of Urban and Environmental Sciences Northwest UniversityXi’an710127China Department of Biology San Diego State UniversitySan DiegoCA92182USA Key Laboratory of Biodiversity Formation Mechanism and Comprehensive Utilization in Qinghai-Tibet Plateau School of Life SciencesQinghai Normal UniversityXining810008China College of Agronomy Northwest A&F UniversityYangling712100China The College of Life Sciences Northwest UniversityXi’an710072China Carbon Neutrality College (Yulin) Northwest UniversityXi’an710127China

CH_(4) emission rates followed an increased pattern during the growing season at Tibetan Plateau.•Unique genes carried by abundant species were positively correlated with CH_(4) emission rates.•Climate factors influenced CH_(4) emission rates by regulating microbial community and their *** play pivotal roles in soil methane(CH_(4))emissions and their functional genes are origins of a key mechanism for soil ***,understanding of the roles of specific genes(e.g.,unique or shared genes carried by species)underlying CH_(4)-cycling remains ***,we measured CH_(4) emission rates and investigated variations in microbial community and the abundance of genes carried by species during the growing season in alpine meadow on the Tibetan *** discovered that CH_(4) emission rates increased from 394.4,745.9,and 1092.7µg CH4 m−2 h−1,in April,June,and August,respectively,and had a positive correlation with unique genes carried by abundant species during the growing ***,we found that unique genes carried by abundant species involved in methanogenesis processes have a higher abundance than methanotrophic *** analysis indicated that climate factors(i.e.,mean monthly temperature(MMT)and mean monthly precipitation(MMP))influenced microbial community and their functional genes,and therefore affected the CH_(4) emission ***,the present study provides a novel insight into the variation of soil CH4 emissions from a functional gene perspective,highlighting the important roles of unique genes carried by abundant species in CH4 emissions in the Tibetan Plateau under seasonal variation.

关键词： soil CH_(4) emissions unique genes abundant species CH_(4)-cycling growing season

Human adipose, placenta, and umbilical cord-derived mesenchymal stem cells ameliorate imiquimod-induced psoriatic mice via reducing T cells infiltration

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BIOCELL 2021年第3期45卷 537-546页

作者： JIGANG LEI ZHENYAO XU SUKE LI MENG LI ZHIKAI WANG PING LI JING WANG YINGLU CHEN X IAOLE SONG chengjie ren MEIPING SHEN CHENGXIANG DAI Cellular Biomedicine Group Shanghai200233China Translational Medicine Center Shanghai General HospitalShanghai Jiaotong University School of MedicineShanghai200025China Shanghai Institute of Immunology Shanghai Jiaotong University School of MedicineShanghai200025China

Psoriasis is an autoimmune-related chronic inflammatory disease with an approximate prevalence of 2–3%around the world,involving increased keratinocyte ***,Th17 cells and IL-17 play critical roles in the pathogenesis of *** monoclonal antibodies against cytokines have been shown to have effectively immunosuppressive effects on human ***,there are still some patients that have no response to these *** patients have even serious side-effects which may affect their *** stem cells have the ability of immunosuppressive and anti-inflammatory effects,which may be an alternative therapy with more safety and efficacy for human ***,the underlying mechanisms by which the MSCs prevent or ameliorate psoriasis are still poorly ***,we first isolated and characterized human adipose,placenta,and umbilical cord-derived mesenchymal stem cells(haMSCs,hpMSCs,and huMSCs).After that,the animal model of imiquimod(IMQ)-induced psoriasis in C57BL/6 mice was *** investigated the impact of haMSCs,hpMSCs,and huMSCs on this model by H&E staining,immunohistochemistry staining,and quantitative real-time *** analysis showed that mice subcutaneously injected with these MSCs had a significantly decreased epidermal thickness,which was caused by obviously reduced hyper-proliferation of ***,our findings revealed that the infiltration of T cells to psoriatic lesions in IMQ-induced psoriasis mice was markedly downregulated by intradermal administration of haMSCs,hpMSCs,and huMSCs,***,the production of IL-17 from Th17 cells was reduced,which inhibits the proliferation of keratinocytes in lesioned skin of IMQ-induced psoriasis *** data suggest that haMSCs,hpMSCs,and huMSCs can inhibit the effects of proinflammatory Th17 cells on the development of psoriasis,which may be potential therapeutic candidates for skin inflammatory disease or other autoimmune

关键词： Mesenchymal stem cells Psoriasis T cells Skin inflammation Cell therapy

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基于GRU自编码器的船舶航线提取

智能系统学报 2022年第6期17卷 1201-1208页

作者：任成杰陈怀新谢卫电子科技大学资源与环境学院四川成都611731 中国电子科技集团公司第十研究所四川成都610036

船舶自动识别系统(automatic identification system, AIS)数据中蕴含着大量的船舶行为相关信息,从中提取出有效的航线,在海事监管、船只勘查等方面具有广泛应用。本文提出一种基于GRU自编码器(gate recuurent unit auto-encoder,GRU-AE... 详细信息

船舶自动识别系统(automatic identification system, AIS)数据中蕴含着大量的船舶行为相关信息,从中提取出有效的航线,在海事监管、船只勘查等方面具有广泛应用。本文提出一种基于GRU自编码器(gate recuurent unit auto-encoder,GRU-AE)的船舶航线提取方法,首先采用GRU编码器将原始轨迹数据编码为统一格式的深度特征信息,其次利用DBSCAN (density-based spatial clustering of applications with noise)算法对深度特征信息进行聚类,最后将深度特征类簇中心通过解码器反演生成相应的船舶航线,从而实现在海量AIS数据中挖掘船舶轨迹规律。以波士顿港口为例,分析一年时间内10万多条AIS的船舶航行数据,实验表明本方法可对不同长度轨迹数据进行聚类及其航线提取,并可支撑船舶轨迹异常检测、路径规划、位置预测等研究,具有较好的应用适应性。

关键词：航线提取船舶自动识别系统数据挖掘 GRU自编码器深度特征解码反演 DBSCAN算法轨迹聚类

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秦岭太白山不同海拔锐齿栎林土壤微生物群落的变化特征

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林业科学 2021年第12期57卷 22-31页

作者：李益冯秀秀赵发珠郭垚鑫王俊任成杰陕西省地表系统与环境承载力重点实验室西安710127 西北大学城市与环境学院西安710127 西北农林科技大学农学院杨凌712100 西北大学生命科学学院西安710127

【目的】研究秦岭太白山锐齿栎林4种不同海拔土壤微生物多样性及群落组成特征,以期阐明同一植被类型土壤微生物群不同海拔的变化规律及驱动因素。【方法】在秦岭太白山4个海拔梯度(1361.6、1524.2、1630.5和1769.3 m),选取排水较好、坡... 详细信息

【目的】研究秦岭太白山锐齿栎林4种不同海拔土壤微生物多样性及群落组成特征,以期阐明同一植被类型土壤微生物群不同海拔的变化规律及驱动因素。【方法】在秦岭太白山4个海拔梯度(1361.6、1524.2、1630.5和1769.3 m),选取排水较好、坡度较缓、长势适中的3个锐齿栎林标准样地(20 m×20 m),于2016年8月,用“S”型方法于每块样地进行0~10 cm土层的混合取样,利用高通量测序技术测定土壤微生物群落多样性及组成。【结果】1)不同海拔梯度的锐齿栎林土壤细菌多样性(α多样性和β多样性)变化显著,但真菌多样性无显著变化。2)在细菌群落组成中,随海拔升高,放线菌的相对丰度显著降低,而变形菌和疣微菌的相对丰度显著增加,绿弯菌、芽单胞菌和硝化螺旋菌的相对丰度呈先增后降的变化;其他细菌类群如酸杆菌和浮霉菌的相对丰度呈不显著降低。在真菌群落组成中,作为2个优势菌门的担子菌和子囊菌的相对丰度随海拔增加的变化不显著。3)细菌多样性与土壤有机碳(SOC)含量、全氮(TN)含量、C∶P和N∶P显著正相关,其群落组成对海拔梯度的响应差异主要取决于土壤密度、温度、SOC、C∶P和TN;真菌群落多样性及组成受土壤养分差异的影响较小。在植被相同但海拔不同的条件下,受气候及土壤养分的差异影响,细菌群落特征较真菌群落的变化明显。【结论】秦岭太白山锐齿栎林土壤细菌和真菌多样性沿海拔梯度呈先增后减的变化趋势。海拔对细菌群落的影响大于真菌群落。研究结果揭示了秦岭暖温带森林生态系统土壤微生物群落结构和组成的变化特征及影响因素,从而为深入理解森林生态系统土壤有机碳分解的微生物机制提供科学依据。

关键词：森林生态系统海拔梯度锐齿栎林 Illumina测序土壤微生物群落土壤养分

黄土丘陵区不同恢复年限退耕林地土壤碳氮差异及其影响因素

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西北农林科技大学学报（自然科学版） 2017年第6期45卷 123-133页

作者：吴建平韩新辉任成杰杨改河任广鑫西北农林科技大学农学院陕西杨凌712100 陕西省循环农业工程技术研究中心陕西杨凌712100

【目的】研究黄土丘陵区不同退耕年限林地有机碳及全氮的差异性,分析全氮及有机碳与环境和土壤因子的关系,为该区域生态恢复与土壤质量评价提供科学参考。【方法】结合野外调查和室内分析,运用统计分析及冗余分析方法(RDA),以耕地(CL)... 详细信息

【目的】研究黄土丘陵区不同退耕年限林地有机碳及全氮的差异性,分析全氮及有机碳与环境和土壤因子的关系,为该区域生态恢复与土壤质量评价提供科学参考。【方法】结合野外调查和室内分析,运用统计分析及冗余分析方法(RDA),以耕地(CL)为对照,对黄土丘陵区退耕种植25,35,40年的柠条(Caragana korshinskii Lam.,CK)、刺槐(Robinia pseudoacacia L.,RP)林地(以下分别用CK25a、CK35a、CK40a、RP25a、RP35a、RP40a表示)为研究对象,分别采集各样地0~10,10~20,20~30cm土层的土样,研究0~30cm土层有机碳、全氮含量及有机碳密度、全氮密度、微生物生物量碳、微生物生物量氮随退耕年限的变化特征,最后分析了土壤有机碳、全氮含量及有机碳密度、全氮密度与环境因子、土壤因子的关系。【结果】与耕地相比,不同退耕年限刺槐、柠条林地0~30cm土层土壤有机碳、全氮、微生物生物量碳、微生物生物量氮含量及有机碳密度、全氮密度显著增加,在0~30cm土层,有机碳、全氮、微生物生物量碳和微生物生物量氮含量由大到小依次为RP40a>RP35a>RP25a>CL;有机碳密度从高到低依次为CK35a>CK40a>CK25a>CL;全氮密度由大到小依次是CK35a>CK25a>CK40a>CL。对于不同退耕年限的刺槐和柠条林地,环境因子中的植被盖度、退耕年限、坡度均与土壤有机碳、全氮及有机碳密度、全氮密度呈正相关,坡向、海拔、土壤体积质量、pH均与其呈负相关。而土壤因子中的微生物生物量碳、微生物生物量氮、总孔隙度均与有机碳、全氮及有机碳密度、全氮密度呈正相关,土壤体积质量、pH均与其呈负相关。【结论】土壤有机碳及全氮含量变化与退耕年限、植被盖度、坡度及土壤因子存在密切关系,且植被恢复使土壤质量得到了极大改良。

关键词：黄土丘陵区退耕年限退耕林地环境因子土壤有机碳土壤全氮

我国森林土壤微生物生物量碳的纬度分布特征及影响因子

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林业科学 2022年第2期58卷 49-57页

作者：周莎马寰菲王洁莹任成杰郭垚鑫王俊赵发珠西北大学城市与环境学院陕西省地表系统与环境承载力重点实验室西安710127 西北农林科技大学农学院杨凌712100 西北大学生命科学学院西安710127 中国科学院水利部水土保持研究所杨凌712100

【目的】探讨土壤微生物生物量碳(MBC)含量的纬度变化规律及驱动因子,以期揭示我国沿纬度分布的森林生态系统中土壤MBC含量变化的效应和机制,为气候变暖条件下阐明土壤MBC周转和固持提供理论依据。【方法】在我国沿纬度选取10个典型森... 详细信息

【目的】探讨土壤微生物生物量碳(MBC)含量的纬度变化规律及驱动因子,以期揭示我国沿纬度分布的森林生态系统中土壤MBC含量变化的效应和机制,为气候变暖条件下阐明土壤MBC周转和固持提供理论依据。【方法】在我国沿纬度选取10个典型森林生态系统,测定0~10 cm土层的MBC含量,并与各非生物因素(气候条件和土壤理化性质指标)进行相关性分析。【结果】森林土壤MBC含量变化范围为(200.57±13.99)~(913.32±39.62)mg·kg^(-1),随纬度降低而降低。MBC含量与土壤的有机碳含量(r=0.64,P<0.01)、砂砾含量(r=0.48,P<0.01)、水解酶活性(r=0.48,P<0.01)、全磷含量(r=0.47,P<0.01)、pH值(r=0.43,P<0.01)、全氮含量(r=0.31,P<0.01)和土壤有机碳化学结构组分中烷基碳含量(r=0.21,P<0.01)极显著正相关,与土壤粉粒含量(r=0.15,P<0.05)和氧化酶活性(r=0.15,P<0.05)显著正相关;还与年均气温(MAT,r=0.31,P<0.01)极显著正相关。【结论】森林土壤的MBC含量随纬度降低而降低,主要影响因素为土壤质地、土壤营养、土壤酶活性和土壤烷基碳含量,其次为年均气温。

关键词：森林土壤微生物生物量碳纬度梯度土壤理化性质气候条件烷基碳