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Estimating the optimal vegetation coverage for the dominant tree and shrub species over China's northwest drylands

Science China Earth Sciences 2024年第5期67卷 1500-1517页

作者： Zhongdian ZHANG xiaoxu jia Ping ZHU Mingbin HUANG Lidong REN Ming’an SHAO School of Geographic Sciences Xinyang Normal UniversityXinyang 464000China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China Yellow River Delta Modern Agricultural Engineering Laboratory Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationNorthwest A&F UniversityYangling 712100China

Anthropogenic revegetation is an effective way to control soil erosion and restore degraded ecosystems in China's northwest drylands(NWD).However,excessive vegetation cover expansion has long been known to increase evapotranspiration,leading to reduced local water availability,which can in turn threaten the health and services of restored ecosystems.Determining the optimal vegetation coverage(OVC)is critical for balancing the trade-off between plant growth and water consumption in water-stressed areas,yet quantitative assessments over the entire NWD are still lacking.In this study,a modified Biome BioGeochemical Cycles(Biome-BGC)model was used to simulate the long-term(1961–2020)dynamics of actual evapotranspiration(ET_(a)),net primary productivity(NPP),and leaf area index(LAI)for the dominant non-native tree(R.pseudoacacia and P.sylvestris)and shrub(C.korshinkii and H.rhamnoides)species at 246 meteorological sites over NWD.The modified model incorporated the Richards equation to simulate transient unsaturated water flow in a multilayer soil module,and both soil and eco-physiological parameters required by the model were validated using field-observed ETadata for each species.Spatial distributions of OVC(given by the mean maximum LAI,LAI_(max))for the dominant species were determined within three hydrogeomorphic sub-areas(i.e.,the loess hilly-gully sub-area,the windy and sandy sub-area,and the desert sub-area).The modified Biome-BGC model performed well in terms of simulating ET_(a) dynamics for the four plant species.Spatial distributions of mean ET_a,NPP,and LAI_(max)generally exhibited patterns similar to mean annual precipitation(MAP).In the loess hilly-gully sub-area(MAP:210 to 710 mm),the OVC respectively ranged from 1.7 to 2.9 and 0.8 to 2.9 for R.pseudoacacia and H.rhamnoides.In the windy and sandy sub-area(MAP:135 to 500 mm),the OVC ranged from 0.3 to 3.3,0.5 to 2.6 and 0.6 to 2.1for P.sylvestris,C.korshinkii and H.rhamnoides,respectively.In the desert sub-area(MAP:90 to 500 mm),the OVC ranged from 0.4 t

关键词： Optimal vegetation coverage Water balance Leaf area index Biome-BGC model Dryland

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Estimation and testing of linkages between forest structure and rainfall interception characteristics of a Robinia pseudoacacia plantation on China’s Loess Plateau

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Journal of Forestry Research 2022年第2期33卷 529-542页

作者： Changkun Ma Yi Luo Mingan Shao xiaoxu jia State Key Laboratory of Eco-Hydraulics in Northwest Arid Region Xian University of TechnologyXianChina Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100190China

Understanding the interaction between canopy structure and the parameters of interception loss is essential in predicting the variations in partitioning rainfall and water resources as affected by changes in canopy structure and in implementing water-based management in semiarid forest plantations.In this study,seasonal variations in rainfall interception loss and canopy storage capacity as driven by canopy structure were predicted and the linkages were tested using seasonal filed measurements.The study was conducted in nine 50 m×50 m Robinia pseudoacacia plots in the semiarid region of China’s Loess Plateau.Gross rain-fall,throughfall and stemflow were measured in seasons with and without leaves in 2015 and 2016.Results show that measured average interception loss for the nine plots were 17.9% and 9.4% of gross rainfall during periods with leaves (the growing season) and without leaves, respectively. Average canopy storage capacity estimated using an indirect method was 1.3 mm in the growing season and 0.2 mm in the leafless season. Correlations of relative interception loss and canopy storage capacity to canopy variables were highest for leaf/wood area index (LAI/WAI) and canopy cover, fol-lowed by bark area, basal area, tree height and stand density. Combined canopy cover, leaf/wood area index and bark area multiple regression models of interception loss and canopy storage capacity were established for the growing season and in the leafless season in 2015. It explained 97% and 96% of the variations in relative interception loss during seasons with and without leaves, respectively. It also explained 98% and 99% of the variations in canopy storage capacity during seasons with and without leaves, respectively. The empiri-cal regression models were validated using field data col-lected in 2016. The models satisfactorily predicted relative interception loss and canopy storage capacity during seasons with and without leaves. This study provides greater under-standing about the effects of changes in tree canopy struc

关键词： Rainfall interception loss Canopy storage Canopy structure Regression models China’s Loess Plateau

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Internal m6A and m7G RNA modifications in hematopoietic system and acute myeloid leukemia

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中华医学杂志(英文版) 2024年第9期137卷 2024 Mar 28页

作者： Zhang xiaoxu Ma Yanni Yu jia Su Rui Wang Xiaoshuang State Key Laboratory of Common Mechanism Research for Major Diseases State Key Laboratory for Complex Severe and Rare Diseases Institute of Basic Medical Sciences Chinese Academy of Medical Sciences / Peking Union Medical College Beijing China Department of Systems Biology Beckman Research Institute of City of Hope Monrovia CA USA The Institute of Blood Transfusion Chinese Academy of Medical Sciences / Peking Union Medical College Chengdu Sichuan China Key Laboratory of RNA and Hematopoietic Regulation Chinese Academy of Medical Sciences Beijing China Department of Biochemistry and Molecular Biology Chinese Academy of Medical Sciences School of Basic Medicine Peking Union Medical College Beijing China

Epitranscriptomics focuses on the RNA-modification-mediated post-transcriptional regulation of gene expression. The past decade has witnessed tremendous progress in our understanding of the landscapes and biological functions of RNA modifications, as prompted by the emergence of potent analytical approaches. The hematopoietic system provides a lifelong supply of blood cells, and gene expression is tightly controlled during the differentiation of hematopoietic stem cells (HSCs). The dysregulation of gene expression during hematopoiesis may lead to severe disorders, including acute myeloid leukemia (AML). Emerging evidence supports the involvement of the mRNA modification system in normal hematopoiesis and AML pathogenesis, which has led to the development of small-molecule inhibitors that target N6-methyladenosine (m6A) modification machinery as treatments. Here, we summarize the latest findings and our most up-to-date information on the roles of m6A and N7-methylguanine in both physiological and pathological conditions in the hematopoietic system. Furthermore, we will discuss the therapeutic potential and limitations of cancer treatments targeting m6A.

关键词： N6-methyladenosine N7-methylguanine Hematopoiesis Acute myeloid leukemia Therapeutic target RNA modifications

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An empirical approach to predict regional organic carbon in deep soils

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Science China Earth Sciences 2023年第3期66卷 583-593页

作者： Jingjing WANG Xiaorong WEI xiaoxu jia Mingbin HUANG Zhipeng LIU Yufei YAO Ming’an SHAO State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F UniversityYangling 712100China Institute of Soil and Water Conservation Ministry of Water Resources and Chinese Academy of SciencesYangling 712100China CAS Center for Excellence in Quaternary Science and Global Change Xi’an 710061China Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environmental Sciences Nanjing Agricultural UniversityNanjing 210095China College of Urban and Environmental Sciences Northwest UniversityXi’an 710127China

Deep soil organic carbon(SOC)plays an important role in carbon cycling.Precisely predicting deep SOC at the regional scale is crucial for the accurate assessment of carbon sequestration potential in soils but has been challenging for a century.Herein,we developed a depth distribution function-based empirical approach to predict SOC in deep soils at the regional scale.We validated this approach with a dataset from four regions of the world and examined the application of this approach in China’s Loess Plateau.We found that among the reported depth distribution functions describing vertical patterns of SOC,the negative exponential function performed best in fitting SOC along the soil profile in various regions.Moreover,the parameters(i.e.,Ceand k)of the negative exponential function were linearly correlated to surface SOC(0–20 cm)and the changing rates of SOC within the topsoil(0–40 cm).Based on the above relationships,the empirical equations for predicting the negative exponential parameters are established.The validation results from site-specific and regional dataset showed that combining the negative exponential function and such empirical equations can precisely predict SOC concentration in soils down to 500 cm depth.Our study provides a simple,rapid and accurate method for predicting deep soil SOC at the regional scale,which could simplify the assessment of deep soil SOC in various regions.

关键词： Deep SOC Empirical approach Negative exponential function Depth distribution Spatial pattern

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What is the mass of loess in the Loess Plateau of China?

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Science Bulletin 2019年第8期64卷 534-539页

作者： Yuanjun Zhu xiaoxu jia jiangbo Qiao Ming'an Shao State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F University Institute of Soil and Water Conservation Chinese Academy of Sciences & Ministry of Water Resources College of Resources and Environment University of Chinese Academy of Sciences Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

The Loess Plateau of China(LP) has the largest and thickest loess deposits in the world. Quantifying the amount of loess in the LP is crucial for investigating the accumulation and erosion of loess, and determining the regional soil and water resource capacity. We used loess thickness data, a pedotransfer function for bulk density(BD), and the clay content data observed in 242 sites across the LP to derive the BD of loess and then estimate the loess mass and its distribution across the LP. The results indicated that the average BD of loess between the surface and bedrock is 1.58 g cm^(-3), varying from 1.18 to 1.87 g cm^(-3).The total loess mass is approximately 5.45 ? 10^(13) t, and the average loess mass over an area of 1 m^2 is 169 t, ranging from 1.36 to 585 t. The greatest mass of loess is in the south-central of the LP while the lowest mass of loess is in the northwest and river valley areas. Our estimate of loess mass provides key data for calculating water, carbon, and nutrient storages in the LP, which improves our understanding of soil-water processes and ecohydrological systems in this landscape.

关键词： The Loess Plateau Loess mass Pedotransfer function Soil erosion Bulk density

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Panax notoginseng saponin attenuates hypoxia/reoxygenation-induced oxidative stress in cortical neurons

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Neural Regeneration Research 2012年第36期7卷 2853-2859页

作者： Chen Yan Jinqiang Zhu xiaoxu jia Chao Wang Shaoxia Wang Liyuan Kang Key Laboratory for Prescription of National Educational Ministry of China Research Center of Traditional Chinese MedicineTianjin University of Traditional Chinese Medicine

The present study monitored the effect of 2, 10, and 50 mg/L of Panax notoginseng saponin exposure following hypoxia-reoxygenation injury in fetal rat cortical neurons. Results showed that varying doses of Panax notoginseng saponin significantly enhanced the cell viability of neurons, reduced malondialdehyde content, increased superoxide dismutase activity, inhibited mRNA and protein expression of inducible and neuronal nitric oxide synthase, and decreased the release of nitric oxide in hypoxia/reoxygenation injured cells. In particular, 50 mg/L of Panax notoginseng saponin was the most effective dose. These findings suggest that Panax notoginseng saponin can attenuate neuronal oxidative stress injury caused by hypoxia/reoxygenation in a dose-dependent manner.

关键词： Panax notoginseng saponin neuron oxidative stress superoxide dismutase malondialdehyde nitric oxide neuroprotection nerve injury neural regeneration

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Response of soil CO_2 efflux to precipitation manipulation in a semiarid grassland

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Journal of Environmental Sciences 2016年第7期28卷 207-214页

作者： Xiaorong Wei Yanjiang Zhang jian Liu Hailong Gao Jun Fan xiaoxu jia Jimin Cheng Mingan Shao Xingchang Zhang State Key Laboratory of Soil Erosion and Dryland Farming in the Loess Plateau Northwest A&F University College of Animal Science and Technology Northwest A&F University Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of Sciences

Soil CO_2efflux（SCE） is an important component of ecosystem CO_2 exchange and is largely temperature and moisture dependent, providing feedback between C cycling and the climate system. We used a precipitation manipulation experiment to examine the effects of precipitation treatment on SCE and its dependences on soil temperature and moisture in a semiarid grassland. Precipitation manipulation included ambient precipitation, decreased precipitation（- 43%）, or increased precipitation（＋ 17%）. The SCE was measured from July2013 to December 2014, and CO_2 emission during the experimental period was assessed.The response curves of SCE to soil temperature and moisture were analyzed to determine whether the dependence of SCE on soil temperature or moisture varied with precipitation manipulation. The SCE significantly varied seasonally but was not affected by precipitation treatments regardless of season. Increasing precipitation resulted in an upward shift of SCE–temperature response curves and rightward shift of SCE–moisture response curves,while decreasing precipitation resulted in opposite shifts of such response curves. These shifts in the SCE response curves suggested that increasing precipitation strengthened the dependence of SCE on temperature or moisture, and decreasing precipitation weakened such dependences. Such shifts affected the predictions in soil CO_2 emissions for different precipitation treatments. When considering such shifts, decreasing or increasing precipitation resulted in 43 or 75% less change, respectively, in CO_2 emission compared with changes in emissions predicted without considering such shifts. Furthermore, the effects of shifts in SCE response curves on CO_2 emission prediction were greater during the growing than the non-growing season.

关键词： Soil CO2 efflux response curve Soil moisture Soil temperature Precipitation regimes Semiarid grassland Soil CO2 efflux

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禽肉预制菜产业的发展现状及其质量安全的影响因素与提升策略

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中国农业科技导报 2024年第6期26卷 133-140页

作者：黄胜海唐修君贾晓旭马丽娜刘茵茵高玉时江苏省家禽科学研究所江苏扬州225125

禽肉预制菜对提高人们生活水平、乡村振兴、餐饮业标准化、家禽业高质量发展具有重要作用。然而,禽肉预制菜的生产经营与消费过程中存在诸多影响质量安全的不利因素。对家禽养殖和屠宰,禽肉预制菜的加工、包装、贮藏与运输、销售与消费... 详细信息

禽肉预制菜对提高人们生活水平、乡村振兴、餐饮业标准化、家禽业高质量发展具有重要作用。然而,禽肉预制菜的生产经营与消费过程中存在诸多影响质量安全的不利因素。对家禽养殖和屠宰,禽肉预制菜的加工、包装、贮藏与运输、销售与消费等环节中影响质量安全的因素进行分析;从家禽生态养殖环境的建立与投入品管理、家禽屠宰的场地建设与生产管理、禽肉预制菜加工工艺与绿色标签制度的实施、包装材料的选择与包装技术的应用、贮藏与运输中科学管理体系的建立与信息技术的应用、销售管理制度的健全与对消费者的科学指导等方面提出相应的优化策略,以促进禽肉预制菜质量安全的提升和产业发展,为乡村振兴、“三农”问题的解决、家禽业和餐饮业的发展、人民群众对美好生活的需要和生态文明建设提供理论基础和模式借鉴。

关键词：禽肉预制菜质量安全产业发展提升策略

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基于线粒体16S rRNA基因的鹅肉源性成分鉴别方法研究

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中国家禽 2024年第5期46卷 108-112页

作者：盛中伟樊艳凤贾晓旭高玉时陆俊贤唐修君江苏省家禽科学研究所江苏扬州225125

研究旨在建立基于线粒体16S rRNA基因的鹅源性成分鉴别方法。试验以鹅源性DNA为阳性模板,以猪、牛、羊、鸽、鹌鹑、火鸡、鸡和鸭等8个物种DNA为干扰模板的混合模板,设计筛选出鹅特异性引物,进行PCR和荧光定量PCR(qPCR)反应,并将鹅肉DNA... 详细信息

研究旨在建立基于线粒体16S rRNA基因的鹅源性成分鉴别方法。试验以鹅源性DNA为阳性模板,以猪、牛、羊、鸽、鹌鹑、火鸡、鸡和鸭等8个物种DNA为干扰模板的混合模板,设计筛选出鹅特异性引物,进行PCR和荧光定量PCR(qPCR)反应,并将鹅肉DNA模板浓度按101~1088个梯度进行稀释,检测方法灵敏度。结果显示:所设计的引物仅对鹅肉DNA有特异性扩增,对鹅以外的其他8个物种均没有扩增;当鹅肉DNA模板稀释104倍,PCR扩增条带仍然清晰;当稀释倍数达到107时,仍有较好的扩增曲线,且Ct值小于35。研究表明,建立的畜禽肉中鹅源性成分PCR和qPCR鉴别方法不仅具有良好的特异性,而且具有较高的灵敏性,为食品中鹅源性成分的鉴别提供了新途径。

关键词：鹅肉 16S rRNA基因荧光定量PCR 源性成分检测

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濒临灭绝品种彭县黄鸡遗传多样性的研究

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中国禽业导刊 2024年第1期41卷 58-59页

作者：强伟平贾晓旭高玉时溧阳市畜牧兽医站江苏常州213399 江苏省家禽科学研究所江苏扬州225125

彭县黄鸡因主产于成都平原西部的彭县(现彭州市)及其毗邻地区而得名。当地群众素有喜养黄色母鸡和大红公鸡的习惯,饲养者选产蛋大、产蛋多、生长快而易肥的鸡留种,逐渐形成蛋肉兼用型的彭县黄鸡。20世纪80年代前,彭县黄鸡是彭州市及周... 详细信息

彭县黄鸡因主产于成都平原西部的彭县(现彭州市)及其毗邻地区而得名。当地群众素有喜养黄色母鸡和大红公鸡的习惯,饲养者选产蛋大、产蛋多、生长快而易肥的鸡留种,逐渐形成蛋肉兼用型的彭县黄鸡。20世纪80年代前,彭县黄鸡是彭州市及周边地区饲养的主要品种,1981年彭县饲养黄鸡约28.5万只。80年代中期以后,由于国外高产蛋鸡和快长型肉鸡品种的引入和大面积推广,彭县黄鸡饲养量越来越少,被《全国畜禽遗传资源保护和利用“十三五”规划》列为濒临灭绝品种。现有种群是在61只彭县黄鸡(公鸡10只,母鸡51只)的基础上,经过抢救性保护,扩繁而来的。由于彭县黄鸡扩繁基础群体数量太少,定期对现有群体进行遗传结构及其遗传多样性进行评价是十分必要的。

关键词：彭县黄鸡畜禽遗传资源高产蛋鸡肉鸡品种群体数量兼用型遗传多样性遗传结构

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