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基于土地利用变化的黄河上游四川段生态系统服务价值评价

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水土保持学报 2024年第2期38卷 178-189页

作者：许诺瑾丁兵兵余新晓贾国栋冯岩开林佳雯北京林业大学水土保持学院北京100083 水土保持国家林业和草原局重点实验室北京100083

[目的]通过定量研究20年间黄河上游四川段土地利用变化与生态系统服务价值的关系,评估该流域段生态综合治理效果,为健全民族区域空间规划、生态环境保护与管理提供依据,助力黄河流域高质量发展。[方法]利用黄河上游四川段2000年、2010年... 详细信息

[目的]通过定量研究20年间黄河上游四川段土地利用变化与生态系统服务价值的关系,评估该流域段生态综合治理效果,为健全民族区域空间规划、生态环境保护与管理提供依据,助力黄河流域高质量发展。[方法]利用黄河上游四川段2000年、2010年和2020年土地利用数据,基于土地利用动态度、土地利用矩阵分析土地利用变化,并参考中国陆地生态系统单位面积生态系统服务价值当量,对黄河上游四川段生态系统服务价值当量的经济价值进行修正,定量研究黄河上游四川段2000-2020年间土地利用变化对生态系统服务价值的影响。[结果](1)2000-2020年黄河上游四川段林地、荒漠、湿地和水系土地利用面积呈上升趋势,耕地、灌木、草地和冰川积雪呈下降趋势,2010-2020年土地利用变化比2000-2010年更显著;(2)黄河上游四川段2000年、2010年和2020年生态系统服务价值分别为1.27×1010,2.51×1010,3.92×1010元,呈上升趋势,敏感性分析表明分析结果可靠。各土地利用类型中,对生态系统总价值贡献最为显著的地类是草地,2000-2010年和2010-2020年草地生态服务贡献率分别为93.90%和72.90%,其次为湿地和林地;(3)研究区在20年间各单项生态系统服务价值均呈增加趋势,区域生态服务功能的分项价值大小均为调节服务>支持服务>供给服务>文化服务,11个单项功能中起显著服务价值的为气候调节、水文调节、土壤保持和生物多样性,4项之和占总价值比例超过69.50%。黄河上游四川段土地利用变化影响区域生态系统服务价值的变化,其中草地影响最显著,其次为湿地和林地。[结论]研究结果表明20年间生态治理成果逐渐增强,生态环境不断变好。

关键词：生态系统服务价值黄河上游四川段土地利用价值当量

Partitioning tree water usage into storage and transpiration in a mixed forest

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Forest Ecosystems 2021年第4期8卷 961-973页

作者： Ziqiang Liu Qianqian Liu Zijun Wei xinxiao yu.guodong jia jiang jiang Co-Innovation Center for Sustainable Forestry in Southern China Nanjing Forestry UniversityNanjing 210037China Key Laboratory of Soil and Water Conservation and Desertification Combating of Ministry of Education Beijing Forestry UniversityBeijing 100083China

Background:Water migration and use are important processes in ***,it is possible to overestimate transpiration by equating the water absorbed through the plant roots to that diffused back to the atmosphere through stomatal ***,it is necessary to quantify the water transpired and stored in ***:The δ^(2)H/δ^(18)O technique and heat ratio method were used to explore the water usage of coniferous and broad-leaved tree species,including the proportions of water used for transpiration and water ***:Platycladus orientalis and Quercus variabilis had strong plasticity in their water usage from different *** orientalis primarily used groundwater(30.5%)and the 60-100-cm soil layer(21.6%)throughout the experimental period and was sensitive to precipitation,absorbing water from the 0-20-cm layer(26.6%)during the rainy *** variabilis absorbed water from all sources(15.7%-36.5%)except from the 40-60-cm soil layer during the dry *** addition,it did not change its water source but increased its groundwater uptake during the rainy *** annual mean water fluxes of *** and *** were 374.69 and 469.50 mm·year−1,with 93.49% and 93.91% of the water used for transpiration,***,nocturnal sap flow in *** and *** was mainly used for water storage in the trunk rather than transpiration,which effectively alleviated drought stress and facilitated the transport of ***:The water stored in both species comprised 6%-7% of the total water fluxes and,therefore,should be considered in water balance models.

关键词： Water migration Water uptake Nocturnal sap flow Transpiration

稻瘟病菌MYB转录因子MoIsw2调控基因的鉴定和功能分析

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福建农林大学学报（自然科学版） 2024年第5期53卷 598-609页

作者：裴梦甜王鑫潇余庆鲁国东李亚福建农林大学植物保护学院闽台作物有害生物生态防控国家重点实验室福建福州350002

【目的】MYB(V-myb avian myeloblastosis viral oncogene homolog)转录因子MoIsw2对稻瘟病菌的生长发育和致病性至关重要。为了深入理解MoIsw2对稻瘟病菌的作用机制,对其调控的基因进行鉴定和功能分析。【方法】对野生型稻瘟病菌菌株K... 详细信息

【目的】MYB(V-myb avian myeloblastosis viral oncogene homolog)转录因子MoIsw2对稻瘟病菌的生长发育和致病性至关重要。为了深入理解MoIsw2对稻瘟病菌的作用机制,对其调控的基因进行鉴定和功能分析。【方法】对野生型稻瘟病菌菌株Ku80和突变体ΔMoisw2进行RNA-seq分析,选择突变体中表达发生明显变化的7个基因(MoEGH16L1、MoEGH16L2、MoSTA-RT1、MoGH61A、MoCTR1、MoFRO1和MoGH31A)作为MoIsw2的候选调控基因,通过基因敲除对其表型和致病性进行分析。【结果】RNA-seq分析表明,突变体ΔMoisw2中差异表达的基因主要涉及氧化还原、细胞膜合成、氨基酸代谢和基因组DNA修复等过程。7个候选调控基因的敲除试验结果表明,这些基因在稻瘟病菌的营养生长、孢子发育和致病等过程中发挥重要作用,各基因突变体表型与突变体ΔMoisw2均具有相似之处。【结论】MoIsw2通过调控多个靶基因参与稻瘟病菌的生长发育和致病过程。

关键词：稻瘟病菌 MYB转录因子 Isw2 转录组测序基因功能

Response of forestland soil water content to heavy rainfall on Beijing Mountain, northern China

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Journal of Forestry Research 2016年第3期27卷 541-550页

作者： jianbo jia xinxiao yu Yitao Li College of Soil and Water Conservation Beijing Forestry University Beijing 100083 People's Republic of China Shanxi Institute of Forest Inventory and Planning Taiyuan 030012 People's Republic of China

Continuous recording of precipitation and soil water content（SWC）, especially during long periods of torrential rainfall, has proven challenging. Over a 16 h period spanning 21-22 July, 2012, Beijing experienced historic rainfall that totaled 164.4 mm. We used large lysimeter technology in four forested plots to record precipitation and variation in SWC at 10-min intervals to quantify the response of forestland SWC to heavy rainfall in a semi-arid area. Mean,maximum and minimum rainfall intensities were 23.4, 46.8and 12.0 mm/h, respectively. Rainfall was concentrated in 2-6 mm bursts that accounted for 67.32 % of the total rainfall event. Soil moisture conditions in this region are strongly dependent on patterns of precipitation. Water infiltration into 20, 40, 60, 80, 100, 120 and 160 cm soil layers required 1, 5,20, 37, 46, 52 and 61 mm of precipitation, respectively, and to fully saturate these soil layers required 80, 120, 140, 150, 180,200 and 220 mm of precipitation, respectively.

关键词： Semi-arid region Soil water content Soilwater deficit Lysimeter

Effects of forest cover type and ratio changes on runoff and its components

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International Soil and Water Conservation Research 2022年第3期10卷 445-456页

作者： Bingbing Ding Yonge Zhang xinxiao yu.guodong jia Yousheng Wang yusong Wang Pengfei Zheng Zedong Li The Metropolitan Area Forest Ecosystem Research Station School of Soil and Water ConservationBeijing Forestry UniversityBeijing100083PR China Key Laboratory of State Forestry and Grassland Administration on Soil and Water Conservation Beijing Forestry UniversityBeijing100083PR China Institute of Sediment Research China Institute of Water Resources and Hydropower ResearchBeijing100038PR China

Changes in forest cover can affect not only the total runoff from a watershed,but also the runoff components(e.g.,surface runoff,interflow,groundwater flow).In this study,based on the WetSpa model simulation method and the recursive digital filtering(RDF)method,the Banchengzi watershed in the mountainous region of Beijing,China,was selected to investigate how changes in forest cover type and cover percentage affect total runoff,surface runoff,interflow,and groundwater flow through scenario *** results show that the difference between the WetSpa model and the RDF method for separating runoff components is small,with only 4.7%and 0.4%difference between the calibration and validation *** runoff in different forest types followed the order shrub forest>coniferous forest>mixed forest>broadleaf *** runoff components,the proportions of baseflow(sum of interflow and groundwater flow)to total runoff were 61.1%and 60.8%for broadleaf and mixed forests,which was significantly higher than those of 53.0%and 43.1%for coniferous and shrub ***,the proportion of shrub forest baseflow was high in wet years,and that of broadleaf forest baseflow was high in normal and dry *** proportions of interflow and groundwater flow from various forest cover types to total runoff continued to increase with increasing forest cover *** results have important implications for the implementation of afforestation projects and forest conservation programs,contributing to water resource regulation and ecosystem protection in watersheds.

关键词： Forest cover types Forest cover ratios WetSpa Runoff separation Runoff components

Learning a discriminative mid-level feature for action recognition

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Science China(Information Sciences) 2014年第5期57卷 195-207页

作者： LIU CuiWei PEI MingTao WU xinxiao KONG yu jia yunDe Beijing Laboratory of Intelligent Information Technology School of Computer ScienceBeijing Institute of Technology

In this paper,we address the problem of recognizing human actions from *** of the existing approaches employ low-level features(e.g.,local features and global features)to represent an action ***,algorithms based on low-level features are not robust to complex environments such as cluttered background,camera movement and illumination ***,we propose a novel random forest learning framework to construct a discriminative and informative mid-level feature from low-level features of densely sampled 3D *** cuboid is classified by the corresponding random forests with a novel fusion scheme,and the cuboid’s posterior probabilities of all categories are normalized to generate a *** that,we obtain our mid-level feature by concatenating histograms of all the *** a single low-level feature is not enough to capture the variations of human actions,multiple complementary low-level features(i.e.,optical flow and histogram of gradient 3D features)are employed to describe 3D ***,temporal context between local cuboids is exploited as another type of low-level *** above three low-level features(i.e.,optical flow,histogram of gradient 3D features and temporal context)are effectively fused in the proposed learning ***,the mid-level feature is employed by a random forest classifier for robust action *** on the Weizmann,UCF sports,Ballet,and multi-view IXMAS datasets demonstrate that out mid-level feature learned from multiple low-level features can achieve a superior performance over state-of-the-art methods.

关键词： action recognition mid-level feature feature fusion temporal context

Variation in water supply leads to different responses of tree growth to warming

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Forest Ecosystems 2022年第1期9卷 23-32页

作者： Pengfei Zheng Dandan Wang guodong jia xinxiao yu Ziqiang Liu yusong Wang Yonge Zhang Key Laboratory of State Forestry Administration on Soil and Water Conservation Beijing Forestry UniversityBeijing100083China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing100038China Co-Innovation Center for Sustainable Forestry in Southern China Nanjing Forestry UniversityNanjing210037China

Background:Global climate change,characterized by changes in precipitation,prolonged growing seasons,and warming-induced water deficits,is putting increased pressure on forest ecosystems *** the impact of climate change on drought-prone forests is a key objective in assessing forest responses to climate ***:In this study,we assessed tree growth trends and changes in physiological activity under climate change based on measurements of tree ring and stable ***,structural equation models were used to identify the climate drivers influencing tree growth for the period 1957–***:We found that the mean basal area increment decreased first and then increased,while the water use efficiency showed a steady *** effects of climate warming on tree growth switched from negative to positive in the period 1957–*** water supply,especially snowmelt water available in the early critical period,combined with an earlier arrival of the growing season,allowed to be the key to the reversal of the effects of warming on temperature *** analysis of structural equation models(SEM)also demonstrated that the growth response of Pinus tabuliformis to the observed temperature increase was closely related to the increase in water ***:Our study indicates that warming is not the direct cause of forest decline,but does indeed exacerbate droughts,which generally cause forest *** availability at the beginning of the growing season might be critical in the adaptation to rising temperatures in *** forests may be better able to withstand rising temperatures if they have sufficient water,with boosted growth even possible during periods of rising temperatures,thus forming stronger carbon sinks.

关键词： Climate change Drought stress Tree rings Stable isotope Snowmelt Temperate forests

Reactive Transport Modeling of Long-Term CO2 Sequestration Mechanisms at the Shenhua CCS Demonstration Project,China

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Journal of Earth Science 2017年第3期28卷 457-472页

作者： guodong Yang Yilian Li Aleks Atrens Danqing Liu Yongsheng Wang Li jia yu Lu School of Environmental Studies China University of GeosciencesWuhan 430074China The Queensland Geothermal Energy Centre of Excellence School of Mechanical and Mining EngineeringThe University of QueenslandSt Lucia Qld 4072Australia China Shenhua Coal Liquefaction Co. Ltd.OrdosOrdos 017209China The Administrative Center for China's Agenda 21 Beijing 100038China

Carbon dioxide injection into deep saline aquifers results in a variety of strongly coupled physical and chemical processes. In this study, reactive transport simulations using a 2-D radial model were performed to investigate the fate of the injected CO2, the effect of CO2-water-rock interactions on mineral alteration, and the long-term CO2 sequestration mechanisms of the Liujiagou Formation sandstone at the Shenhua CCS（carbon capture and storage） pilot site of China. Carbon dioxide was injected at a constant rate of 0.1 Mt/year for 30 years, and the fluid flow and geochemical transport simulation was run for a period of 10 000 years by the TOUGHREACT code according to the underground conditions of the Liujiagou Formation. The results show that different trapping phases of CO2 vary with time. Sensitivity analyses indicate that plagioclase composition and chlorite presence are the most significant determinants of stable carbonate minerals and CO2 mineral trapping capacity. For arkosic arenite in the Liujiagou Formation, CO2 can be immobilized by precipitation of ankerite, magnesite, siderite, dawsonite, and calcite for different mineral compositions, with Ca（2＋）, Mg（2＋）, Fe（2＋） and Na＋ provided by dissolution of calcite, albite（or oligoclase） and chlorite. This study can provide useful insights into the geochemistry of CO2 storage in other arkosic arenite（feldspar rich sandstone） formations at other pilots or target sites.

关键词： carbon capture and storage(CCS) CO2 sequestration geochemical interaction mineral trapping CCS demonstration project reactive transport modeling

一则家用电梯噪声投诉案例的原因分析与整改方案

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中国电梯 2024年第5期35卷 53-55,67页

作者：贾国东刘文超钱有根余忠东西子电梯科技有限公司杭州311305

针对一台家用电梯在安装完成后遭到隔壁业主噪声投诉的案例,对卧室相关的噪声标准要求以及标准适用性进行了讨论,阐述了振动与噪声的关系,对振动传递系数及相关参数的计算方法进行了详细介绍。通过对噪声传播的特点分析,对案例采取了以... 详细信息

针对一台家用电梯在安装完成后遭到隔壁业主噪声投诉的案例,对卧室相关的噪声标准要求以及标准适用性进行了讨论,阐述了振动与噪声的关系,对振动传递系数及相关参数的计算方法进行了详细介绍。通过对噪声传播的特点分析,对案例采取了以橡胶减振垫作为减振隔声的主要措施,并附加其他一些方法的配合,经过两次整改方案的实施,达到了隔壁业主对噪声的要求。

关键词：家用电梯噪声超标振动频率整改