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Effects of land use patterns on slope soil water in the semiarid Loess Plateau,China

Journal of Geographical Sciences 2022年第4期32卷 701-716页

作者： JIAO Lei YANG Wenhui JIA Tian MAIERDANG Keyimu CHEN Weiliang gao guangyao WANG Shuai LIU Jianbo WANG Cong School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China National Observation and Research Station of Earth Critical Zone on the Loess Plateau in Shaanxi Beijing 100875China Faculty of Geographical Science Beijing Normal UniversityTianjin 300387China Tianjin Key Laboratory of Water Resources and Environment Tianjin Normal UniversityXi'an 710061China

Land use patterns(LUPs)are the form in which various land use types are combined spatially,evidently impacting soil water.However,the influence mechanism by which LUPs form remains unclear.In this study,the soil water content(SWC)in the 0–160-cm soil depth was observed in shrubland(SL),mature forestland(MF),grassland(GL)and young forestland(YF)sites on four slopes with different LUPs in the Yangjuangou catchment of the Chinese Loess Plateau.The SWC in SL-YF-SL(13.28%)was significantly greater than that in YF-MF(9.93%),MF-GL-YF(10.38%)and SL-MF(10.83%)and was temporally stable during the study period.The spatial distribution of SWC along the slope differed among the four LUPs.Vegetation characteristics and soil texture mainly determined the spatial variations in SWC in the shallow soil layers(0–40 cm),while topographic factors were the determinants in the deep soil layers(60–160 cm)as well as in the entire soil profile(0–160 cm).The significance of SWC differences among the various land use patterns increased with decreasing precipitation during the growing seasons.YF-MF(77.8 mm)and SL-YF-GL(73.9 mm)required more rainwater than SL-MF(68.2 mm)and MF-GL-MF(67.5 mm)to compensate for the loss of soil water on the monthly scale during the rainy season.Therefore,vegetation restoration should consider land use patterns on hillslopes for soil water conservation.

关键词： land use patterns land management soil water resource vegetation restoration hillslope

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Response of Soil Moisture to Rainfall Event in Black Locust Plantations at Different Stages of Restoration in Hilly-gully Area of the Loess Plateau, China

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Chinese Geographical Science 2020年第3期30卷 427-445页

作者： CHEN Weiliang LI Zongshan JIAO Lei WANG Cong gao guangyao FU Bojie State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of Sci-encesBeijing 100085 University of Chinese Academy of Sciences Beijing 100049China School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China

Precipitation plays an important role in the water supplies that support ecological restoration by sustaining large-scale artificial plantations in arid and semiarid regions, especially black locust(Robinia pseudoacacia) plantations(RP plantations), which are widely planted due to R. pseudoacacia being an excellent pioneer species. Characterizing the response of soil moisture to rainfall events at different stages of restoration is important for assessing the sustainability of restoration in RP plantations. In this study, we quantified the response of soil moisture to rainfall events at different years of restoration(15, 20 and 30 yr) representing different restoration stages in RP plantations in a typical hilly-gully area, i.e., the Yangjuangou Catchment, of the Loess Plateau, China. Over the growing season(June to September) of 2017, smart probes were placed at nine depths(10, 20, 40, 60, 80, 100, 120, 150, and 180 cm below the soil surface) to obtain volumetric soil water information at 30-min intervals in the three RP plantations. The advance of the wetting front was depicted, and the total cumulative water infiltration was measured. Soil moisture was mainly replenished by eight heavy rainfall events(mean rainfall amount = 46.3 mm), accounting for 88.7% of the rainfall during the growing season. The mean soil moisture content profiles of RP plantations at the three restoration stages were ordered as 30-yr(14.07%) > 20-yr(10.12%) > 15-yr(8.03%), and this relationship displayed temporal stability. Soil moisture was primarily replenished by rainfall at the 0-60 cm soil depth, and soil moisture remained stable below the 100-cm soil depth. The rainfall regime influenced the advancement of the wetting front. Here, a single rainfall event of 30 mm was the rainfall threshold for infiltration into the 60-cm soil layer. The total infiltration time ranged from 310.5-322.0 h, but no significant differences were found among RP plantations at different restoration stages. Young and old RP plantations had more total infiltr

关键词： artificial-forest ecosystem hilly-gully area restoration stages soil water replenishment rainfall regimes rainfall event

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Linking vegetation cover patterns to hydrological responses using two process-based pattern indices at the plot scale

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Science China Earth Sciences 2013年第11期56卷 1888-1898页

作者： LIU Yu FU BoJie Lü YiHe gao guangyao WANG Shuai ZHOU Ji State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of Sciences Laboratory of Digital Earth Sciences Institute of Remote Sensing and Digital EarthChinese Academy of Sciences

Vegetation cover pattern is one of the factors controlling hydrological processes.Spatially distributed models are the primary tools previously applied to document the effect of vegetation cover patterns on runoff and soil erosion.Models provide precise estimations of runoff and sediment yields for a given vegetation cover pattern.However,difficulties in parameterization and the problematic explanation of the causes of runoff and sedimentation rates variation weaken prediction capability of these models.Landscape pattern analysis employing pattern indices based on runoff and soil erosion mechanism provides new tools for finding a solution.In this study,the vegetation cover pattern was linked with runoff and soil erosion by two previously developed pattern indices,which were modified in this study,the Directional Leakiness Index(DLI)and Flowlength.Although they use different formats,both indices involve connectivity of sources areas(interpatch bare areas).The indices were revised by bringing in the functional heterogeneity of the plant cover types and the landscape position.Using both artificial and field verified vegetation cover maps,observed runoff and sediment production on experiment plots,we tested the indices’efficiency and compared the indices with their antecedents.The results illustrate that the modified indices are more effective in indicating runoff at the plot/hillslope scale than their antecedents.However,sediment export levels are not provided by the modified indices.This can be attributed to multi-factor interaction on the hydrological process,the feedback mechanism between the hydrological function of cover patterns and threshold phenomena in hydrological processes.

关键词：植被格局覆盖模式水文响应空间分布模型土壤侵蚀机理景观格局分析地表径流连接

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Comparison of transpiration between different aged black locust(Robinia pseudoacacia)trees on the semi-arid Loess Plateau,China

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Journal of Arid Land 2016年第4期8卷 604-617页

作者： JIAOLei LU Nan FU Bojie gao guangyao WANG Shuai JIN Tiantian ZHANG Liwei LIU Jianbo ZHANG Di State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Joint Center(or Global Change Studies Beijing 100875China China Institute of Water Resources andHydropower Research Beijing 100038China College of Tourism and Environment Shaanxi Normal UniversityXi'an 710119China College of Earth and Environmental Science Lanzhou UniversityLanzhou 730000China

Black locust （Robinia pseudoacacia） is widely planted throughout the semi-arid Loess Plateau of China. The spatial distribution of this species at different ages is highly heterogeneous due to restoration and management practices. In this study, we aimed to compare the transpiration levels between different aged black locusts at the tree and stand scales, clarifying the physiological status of this species with different ages. Black locust trees with two representative age classes （12 and 28 years） were selected in the Yangjuangou catchment on the semi-arid Loess Plateau. Sap flux density （Fd） and environmental variables （solar radiation, air temperature, relative humidity and soil water content） were simultaneously monitored throughout the growing season of 2014. Tree transpiration （Et） was the product of Fd and sapwood area （As）, and stand transpiration （Ec） was calculated basing on the stand sap flux density （Js） and stand total sapwood area （AsT）. Stomatal conductance （gs） was measured in a controlled environment and hydraulic conductance was estimated using the relationship between transpiration rate and vapor pressure deficit （VPD）. Our results showed that Et and Ec were higher in the 28-year-old stand than in the 12-year-old stand. The gs and hydraulic conductance of 28-year-old trees were also higher than those of 12-year-old trees, and the two parameters were thus the causes of variations in transpiration between different age classes. After rainfall, mean Fd increased by 9% in 28-year-old trees and by 5% in 12-year-old trees. This study thus suggests that stand age should be considered for estimating transpiration at the catchment and region scales in this area. These results provide ecophysiological evidences that the older black locust trees had more active physiological status than the younger ones in this area. These findings also provide basic information for the management of water resources and forests on the semi-arid Loess Plateau.

关键词： sapflow transpiration stand age afforestation restoration Loess Plateau

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半耳箬竹(竹亚科)的形态补充描述

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广西植物 2024年第4期44卷 650-656页

作者：高丽琴李永龙崔龄杨光耀张文根江西农业大学江西省竹子种质资源与利用重点实验室南昌330045 江西省林业科学院南昌330032

半耳箬竹[Indocalamus semifalcatus(H.R.Zhao et Y.L.Yang)T.P.Yi]在原始文献中仅有部分营养器官的描述。该文通过野外居群调查、室内体视解剖和扫描电子显微镜(SEM)观察,新增了半耳箬竹的花器官描述和叶下表皮微形态特征,完善了其营... 详细信息

半耳箬竹[Indocalamus semifalcatus(H.R.Zhao et Y.L.Yang)T.P.Yi]在原始文献中仅有部分营养器官的描述。该文通过野外居群调查、室内体视解剖和扫描电子显微镜(SEM)观察,新增了半耳箬竹的花器官描述和叶下表皮微形态特征,完善了其营养器官的性状描述,更新了其地理分布。结果表明:(1)繁殖器官性状:花序为圆锥状,小穗及小穗轴密被白色短柔毛,颖片、外稃及内稃光滑无毛,雄蕊3枚,花药紫红色,柱头2,白色,羽毛状。(2)营养体性状:秆高达4.5 m,径达2 cm,箨耳半镰形或微弱,箨片直立紧贴秆,叶耳微弱或无,叶舌上具较发达的纤毛;叶片两面同色且无毛。(3)叶下表皮微形态特征:气孔器凹陷不可见,8~10个长乳突平铺覆盖气孔,硅质体马鞍形,未见有大毛和刺毛。(4)新分布区域1个,即贵州省贵阳市观音山。该种与箬叶竹(I.longiauritus Hand.-Mazz.)最为相似,主要区别在于该种的箨鞘和叶鞘上具有半镰形的箨耳或箨耳缺失,秆高达4.5 m,径达2 cm。

关键词：竹类箬竹属描述 SEM 地理分布

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臂丛神经炎的临床观察和分析

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中华手外科杂志 2024年第2期40卷 150-154页

作者：高一金白鹤李光耀王静威韦勋沙轲广西医科大学第一附属医院创伤骨科手外科南宁530021 广西医科大学第二附属医院创伤骨科南宁530021

目的观察总结臂丛神经炎的临床诊疗,分析诊疗过程中的问题,为临床诊疗提供参考。方法回顾自2014年11月至2022年2月,我们诊治并得到随访的臂丛神经炎患者23例23侧,分别记录患者的病史、病程发展、详细治疗经过、辅助检查结果,并随访评估... 详细信息

目的观察总结臂丛神经炎的临床诊疗,分析诊疗过程中的问题,为临床诊疗提供参考。方法回顾自2014年11月至2022年2月,我们诊治并得到随访的臂丛神经炎患者23例23侧,分别记录患者的病史、病程发展、详细治疗经过、辅助检查结果,并随访评估患者治疗前后的患肢疼痛、感觉、肌力变化情况。结果本组中,损伤累及上干患者20例,累及下干患者2例,全臂丛受累患者1例。所有患者均获得6个月以上的随访,平均(12.43±17.89)个月。末次随访中,16例患肢疼痛严重患者起病后2周至3个月症状均明显减轻或消失。7例患肢麻木明显患者均获得不同程度改善;15例通过保守治疗或药物治疗得到良好的上肢功能恢复;8例进行了手术治疗,其中神经转位7例,功能重建4例(有神经手术后恢复不佳患者),最终均获得良好的恢复。另有1例合并脑瘫患者手术后上肢功能恢复欠佳。结论臂丛神经炎有明显的临床特点,详细的病史了解是诊断的关键;保守治疗对大部分臂丛神经炎有效,当确认恢复不佳时,外科手术的介入是必要的。

关键词：臂丛神经炎诊断鉴鉴别诊断治疗结果

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Large-scale Multi-modal Pre-trained Models: A Comprehensive Survey

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Machine Intelligence Research 2023年第4期20卷 447-482页

作者： Xiao Wang guangyao Chen Guangwu Qian Pengcheng gao Xiao-Yong Wei Yaowei Wang Yonghong Tian Wen gao Peng Cheng Laboratory Shenzhen518055China School of Computer Science and Technology Anhui UniversityHefei230601China School of Computer Science Peking UniversityBeijing100871China College of Computer Science Sichuan UniversityChengdu610065China

With the urgent demand for generalized deep models,many pre-trained big models are proposed,such as bidirectional encoder representations(BERT),vision transformer(ViT),generative pre-trained transformers(GPT),etc.Inspired by the success of these models in single domains(like computer vision and natural language processing),the multi-modal pre-trained big models have also drawn more and more attention in recent years.In this work,we give a comprehensive survey of these models and hope this paper could provide new insights and helps fresh researchers to track the most cutting-edge works.Specifically,we firstly introduce the background of multi-modal pre-training by reviewing the conventional deep learning,pre-training works in natural language process,computer vision,and speech.Then,we introduce the task definition,key challenges,and advantages of multi-modal pre-training models(MM-PTMs),and discuss the MM-PTMs with a focus on data,objectives,network architectures,and knowledge enhanced pre-training.After that,we introduce the downstream tasks used for the validation of large-scale MM-PTMs,including generative,classification,and regression tasks.We also give visualization and analysis of the model parameters and results on representative downstream tasks.Finally,we point out possible research directions for this topic that may benefit future works.In addition,we maintain a continuously updated paper list for large-scale pre-trained multi-modal big models:https://***/wangxiao5791509/MultiModal_BigModels_Survey.

关键词： Multi-modal(MM) pre-trained model(PTM) information fusion representation learning deep learning

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基于风险的检验技术在石油炼化领域中的研究进展

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中国腐蚀与防护学报 2024年第3期44卷 553-566页

作者：丁昱智曹金鑫曹凤婷李涛陶建涛王铁钢杲广尧范其香天津职业技术师范大学、天津高速切削与精密加工重点实验室天津300222 中化蓝天集团有限公司杭州310053 中国石油化工股份有限公司天津分公司装备研究院天津300451 天津因科新创科技有限公司天津300393

基于风险的检验(RBI)是近30年来西方发达国家所采用的一种设备风险管理技术,在石油化工领域应用广泛。RBI利用快速的过程条件来推荐检验策略,这些策略可以预测设备的剩余寿命,从而给出检验方案,提升检验效率,降低检验成本。RBI是一个风... 详细信息

基于风险的检验(RBI)是近30年来西方发达国家所采用的一种设备风险管理技术,在石油化工领域应用广泛。RBI利用快速的过程条件来推荐检验策略,这些策略可以预测设备的剩余寿命,从而给出检验方案,提升检验效率,降低检验成本。RBI是一个风险评估和管理过程,它提供了一种确定最佳检查的方法。RBI可以识别高风险设备和低风险设备,并将检查资源同时集中在高风险设备上。本文介绍了RBI技术方法的类型及实施过程,以及RBI在国内外研究进展及现状,综述了RBI技术在典型石油炼化领域中的研究现状与腐蚀问题,分析风险优先数(RPN)在风险检验中的应用与基于风险检验的动态检验方法,并阐述了RBI技术的优势及目前存在的问题,并在此基础上展望了RBI风险评估的发展方向。

关键词： RBI 检验策略石油炼化腐蚀 RPN

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融入上下文特征提取的非自回归神经机器翻译

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陕西理工大学学报（自然科学版） 2024年第3期40卷 44-51,83页

作者：赵光耀王剑高盛祥余正涛昆明理工大学信息工程与自动化学院云南昆明650504 云南省人工智能重点实验室云南昆明650504

非自回归翻译(NAT)模型是一种消除目标句子中的顺序依赖关系的翻译模型,在推理速度上取得了显著的突破。然而该模型在翻译质量方面存在一些局限,为探究原因,主要对注意机制进行了细致而全面的初步研究,研究结果揭示了NAT模型在捕捉局部... 详细信息

非自回归翻译(NAT)模型是一种消除目标句子中的顺序依赖关系的翻译模型,在推理速度上取得了显著的突破。然而该模型在翻译质量方面存在一些局限,为探究原因,主要对注意机制进行了细致而全面的初步研究,研究结果揭示了NAT模型在捕捉局部性特征方面存在明显不足。为此提出了一种通过明确引入周围词汇信息而改进NAT模型局部性能力的方法。具体而言,在编码器和解码器两个方向上引入了混合分组线性变换,以获得更具局部感知性的表示。通过在WMT14英德与WMT16英罗两个数据集上进行实验,结果表明该方法以微弱的速度代价分别提高了0.7与1.03个BLEU分数,这表明该研究方法在改善NAT模型的局部性特征提取方面具有显著的效果和潜力。

关键词：非自回归局部性特征混合分组线性变换自回归

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黄土高原健康和衰退刺槐林径向生长对气候的响应

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生态学报 2024年第2期44卷 757-769页

作者：李宗善陈维梁焦磊张钦弟李兆林王聪高光耀卫伟孙婧雅白应飞中国科学院生态环境研究中心城市与区域生态国家重点实验室北京100085 陕西黄土高原地球关键带国家野外科学观测研究站西安710061 陕西师范大学地理科学与旅游学院西安710119 山西师范大学生命科学学院太原030032 延安市退耕还林工程管理办公室延安716000

全球气候变化导致的区域森林生长衰退和死亡普遍发生,并对森林生态系统结构和组成以及主要生态系统服务功能产生重要影响,然而相关研究在国内还显偏少。根据黄土高原延安羊圈沟小流域人工刺槐林健康和衰退个体分别构建了刺槐健康和衰退... 详细信息

全球气候变化导致的区域森林生长衰退和死亡普遍发生,并对森林生态系统结构和组成以及主要生态系统服务功能产生重要影响,然而相关研究在国内还显偏少。根据黄土高原延安羊圈沟小流域人工刺槐林健康和衰退个体分别构建了刺槐健康和衰退树轮年表,并对人工刺槐林健康和衰退年表特征及对气候响应敏感性进行了对比分析。结果表明刺槐衰退年表质量较低,其年表统计参量,包括平均敏感度、样芯间相关系数、信噪比和样本群体代表系数均要低于刺槐健康年表。刺槐衰退年表在生活史早期(1985—2007年)与生长健康年表的波动趋势相类似,而在生活史晚期(2008—2016年)与健康年表指数出现生长分离现象,生长速率明显偏低。年表与气候要素响应分析表明刺槐生长衰退年表对气候要素响应敏感性要低于刺槐生长健康年表,但是两者均含有干旱胁迫气候信号,主要体现在与温度呈负相关关系,与降雨和干旱指数的正相关关系。年表与极端气候年份的时序叠加分析表明,生长健康和衰退年表对极端干旱年份响应敏感性均较高,表明极端干旱胁迫条件对刺槐生长健康和衰退个体均有抑制性影响;生长健康年表对极端湿润年份响应敏感性明显高于衰退年表,表明刺槐健康个体比衰退个体更能有效利用湿润年份有利条件,而具有较高的生长速率。研究揭示出黄土高原健康和衰退刺槐个体生长趋势变化及对气候响应敏感性均存在明显差异性,将为气候变化背景下人工刺槐林生长衰退和死亡预测模型建立提供科学依据,因而对黄土高原人工刺槐林生态恢复和保护及可持续经营具有科学价值。

关键词：树木年轮气候响应生长衰退人工刺槐林黄土高原

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