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Changes in freezing and thawing indices over the source region of the Yellow River from 1980 to 2014

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Journal of Forestry Research 2019年第1期30卷 257-268页

作者： Rui Wang qingke zhu Hao Ma School of Geography and Tourism Shaanxi Normal University School of Soil and Water Conservation Beijing Forestry University Northwest Institute of Forest Inventory and Planning and Design State Forestry Administration

Freezing and thawing indices are not only of great significance for permafrost research but also are important indicators of the effects of climate ***,to date,research on ground-surface freezing and thawing indices and their relationship with air indices is *** on daily air and ground-surface temperatures collected from 11 meteorological stations in the source region of the Yellow River,the freezing and thawing indices were calculated,and their spatial distribution and trends were *** air-freezing index(AFI),air-thawing index(ATI),ground surface-freezing index(GFI),ground surface-thawing index(GTI),air thawing-freezing index ratio(Na)and surface ground thawing-freezing index ratio(Ng)were 1554.64,1153.93,1.55,2484.85,850.57℃-days and 3.44,*** affected the spatial distribution of the freezing and thawing *** the altitude increased,the freezing indices gradually increased,and the thawing indices and thawing-freezing index ratio *** 1980 to 2014,the AFI and GFI decreased at rates of 8.61 and 11.06℃-days a^(-1),the ATI and GTI increased at 9.65 and 14.53℃-days a^(-1),and Na and Ng significantly increased at 0.21 and 0.79 decade^(-1).Changes in the freezing and thawing indices were associated with increases in the air and ground-surface *** rates of change of the ground surface freezing and thawing indices were faster than the air ones because the rate of increase of the groundsurface temperature was faster than that of the air and the difference between the ground surface and air *** change point of the time series of freezing and thawing indices occurred in 2000–*** 2000–2001,the AFI and GFI were lower than before the change point,and the changing trend was *** ATI,GTI,Na and Ng during 2001–2014 were higher,with faster rates than *** addition,the annual thawing indices composed a greater proportion of the mean annual air temperature and mean annual ground surfac

关键词： Climate change Freezing and thawing indices Permafrost The source region of the Yellow River

Spatial-temporal variations in near-surface soil freeze-thaw cycles in the source region of the Yellow River during the period 2002–2011 based on the Advanced Microwave Scanning Radiometer for the Earth Observing System(AMSR-E) data

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Journal of Arid Land 2017年第6期9卷 850-864页

作者： WANG Rui zhu qingke MA Hao AI Ning School of Soil and Water Conservation Beijing Forestry University Northwest Institute of Forest Inventory and Planning and Design State Forestry Administration College of Life Science Yan'an University

Detecting near-surface soil freeze-thaw cycles in high-altitude cold regions is important for understanding the Earth＇s surface system, but such studies are rare. In this study, we detected the spatial-temporal variations in near-surface soil freeze-thaw cycles in the source region of the Yellow River（SRYR） during the period 2002–2011 based on data from the Advanced Microwave Scanning Radiometer for the Earth Observing System（AMSR-E）. Moreover, the trends of onset dates and durations of the soil freeze-thaw cycles under different stages were also analyzed. Results showed that the thresholds of daytime and nighttime brightness temperatures of the freeze-thaw algorithm for the SRYR were 257.59 and 261.28 K, respectively. At the spatial scale, the daily frozen surface（DFS） area and the daily surface freeze-thaw cycle surface（DFTS） area decreased by 0.08% and 0.25%, respectively, and the daily thawed surface（DTS） area increased by 0.36%. At the temporal scale, the dates of the onset of thawing and complete thawing advanced by 3.10（±1.4） and 2.46（±1.4） days, respectively; and the dates of the onset of freezing and complete freezing were delayed by 0.9（±1.4） and 1.6（±1.1） days, respectively. The duration of thawing increased by 0.72（±0.21） day/a and the duration of freezing decreased by 0.52（±0.26） day/a. In conclusion, increases in the annual minimum temperature and winter air temperature are the main factors for the advanced thawing and delayed freezing and for the increase in the duration of thawing and the decrease in the duration of freezing in the SRYR.

关键词： Advanced Microwave Scanning Radiometer for the Earth Observing System air temperature near-surface soil freeze-thaw cycles source region of the Yellow River

Impacts of land disturbance and restoration on runoff production and sediment yield in the Chinese Loess Plateau

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Journal of Arid Land 2017年第1期9卷 76-86页

作者： AI Ning WEI Tianxing zhu qingke QIANG Fangfang MA Huan QIN Wei School of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083China College of Life Science Yan'an UniversityYan'an 716000China China Institute of Water Resources and Hydropower Research Beijing 100048China International Research and Training Center on Erosion and Sedimentation Beijing 100048China

Land disturbance and land restoration are important factors influencing runoff production and sediment yield in the semi-arid loess regions of China. This study compared the runoff production and sediment yield during the early stage after land disturbance（ESLD） with those during restoring stage after land disturbance（RSLD）. Grey relational analysis was used to analyse the importance of each one of the influencing factors（vegetation, rainfall, soil and topography） in affecting the runoff production and sediment yield. Our results showed that during ESLD, topography was the most critical factor controlling the runoff production, while soil was the most important factor controlling the sediment yield. During RSLD, vegetation was more important in affecting runoff production, while rainfall was more important in affecting sediment yield. In additional, this study demonstrated that both the runoff production and the sediment yield can be effectively reduced by restoring vegetation on severely-disturbed lands, thus providing an important theoretical basis for better implementations of the Grain for Green Program. Our results revealed that the vegetation types of Hippophae rhamnoides＋Pinus tabulaeformis and H. rhamnoides are better plant selections for land restoration in this area, especially for relatively gentle slopes（i.e., less than 20 degrees）.

关键词： land disturbance/ restoration grey relational analysis runoff sediment yield Loess Plateau

Effects of artificially cultivated biological soil crusts on soil nutrients and biological activities in the Loess Plateau

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Journal of Arid Land 2014年第6期6卷 742-752页

作者： YanMin ZHAO qingke zhu Ping LI LeiLei ZHAO LuLu WANG XueLiang ZHENG Huan MA College of Water and Soil Conservation Beijing Forestry University Key Laboratory of Forest Ecology and Environment State Forestry Administration Research Institute of Forest EcologyEnvironment and ProtectionChinese Academy of Forestry Kunming Forest Exploration & Design Institute of State Forestry Agency Anhui Survey and Design Institute for Water Resources and Hydropower Planning and Design Institute of Forest Products Industry State Forestry Administration

Biological soil crusts （BSCs） play an important role in the early succession of vegetation restoration in the Loess Plateau, China. To evaluate the effects of artificially cultivated BSCs on the soil surface micro-envir- onment, we obtained natural moss crusts and moss-lichen crusts from the Loess Plateau of Shaanxi province, and subsequently inoculated and cultivated on horizontal and sloping surfaces of loess soil in a greenhouse. The chemical and biological properties of the subsoil under cultivated BSCs were determined after 10 weeks of cul- tivation. The results indicated that BSCs coverage was more than 65% after 10 weeks of cultivation. Moss crust coverage reached 40% after 5 weeks of cultivation. Compared with the control, soil organic matter and available nitrogen contents in moss crust with the horizontal treatments increased by 100.87% and 48.23%, respectively; increased by 67.56% and 52.17% with the sloping treatments, respectively; they also increased in moss-lichen crust with horizontal and sloping treatments, but there was no significant difference. Available phosphorus in cultivated BSCs was reduced, soil pH was lower and cationic exchange capacity was higher in cultivated BSCs than in the control. Alkaline phosphatase, urease and invertase activities were increased in artificially cultivated BSCs, and alkaline phosphatase activity in all cultivated BSCs was obviously higher than that in the control. Numbers of soil bacteria, fungi and actinomycetes were increased in the formation process of cultivated BSCs. These results indicate that BSCs could be formed rapidly in short-term cultivation and improve the mi- cro-environment of soil surface, which provides a scientific reference for vegetation restoration and ecological reconstruction in the Loess Plateau. China.

关键词： biological soil crusts soil nutrient enzyme activity soil microorganism Loess Plateau

Effects of microtopography on spatial point pattern of forest stands on the semi-arid Loess Plateau,China

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Journal of Arid Land 2015年第3期7卷 370-380页

作者： WeiJun ZHAO Yan ZHANG qingke zhu Wei QIN ShuZhen PENG Ping LI YanMin ZHAO Huan MA Yu WANG Key Laboratory of Tourist Resources and Environment in Colleges and Universities of Shandong Province Taishan University Forestry Ecological Engineering Research Center (Ministry of Education) Beijing Forestry University Department of Sedimentation China Institute of Water Resources and Hydropower Research Key Laboratory of Forest Ecology and Environment of State Forestry Administration Institute of Forest EcologyEnvironment and ProtectionChinese Academy of Forestry

Microtopography may affect the distribution of forests through its effect on rain redistribution and soil water distribution on the semi-arid Loess Plateau,*** this study,we investigated the characteristics of microtopography on two shady slopes（slope A,5 hm2,uniform slope;slope B,5 hm2,microtopography slope） and surveyed the height,the diameter at breast height and the location（x,y coordinates） of all selected individual trees（Robinia pseudoacacia Linn.,Pyrus betulifolia Bunge,Populus hopeiensis Hu ＆ Chow,Armeniaca sibirica Lam.,Populus simonii *** Ulmus pumila Linn.） on slope A and slope B in the watersheds of Wuqi county,Shaanxi ***,the effects of microtopography on the spatial pattern of forest stands were analyzed using Ripley＇s K（r） *** results showed that：（1） The maximal aggregation radiuses of the tree species on the uniform slope（slope A） were larger than 40 m,whereas those of the tree species on the microtopography slope（slope B） were smaller than 30 m.（2） On slope B,the spatial association of *** with ***,***,*** and *** varied from being strongly negative to positive at microtopography *** spatial association of Populus hopeiensis Hu ＆ Chow with *** also varied from being strongly negative to positive at microtopography ***,there was no spatial association between *** and ***,*** and ***,*** and ***,*** and ***,*** and ***,*** and ***,*** and ***,*** and ***,and *** and *** slope A,the spatial association between tree species were strongly *** results suggest that microtopography may shape tree distribution patterns on the semi-arid Loess Plateau.

关键词： microtopography univariate spatial patterns aggregation negative association positive association

基于GIS和RUSLE的黄土高原小流域土壤侵蚀评估

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农业工程学报 2009年第8期25卷 157-163,I0002页

作者：秦伟朱清科张岩中国水利水电科学研究院泥沙研究所北京100044 北京林业大学水土保持与荒漠化防治教育部重点实验室北京100083

对基于上坡汇流面积的坡长因子算法进行改进,提出考虑上坡土地利用/覆盖对汇流影响的坡长因子算法,运用GIS和RUSLE评估黄土高原四面窑沟流域的土壤侵蚀强度及其与环境因素的关系。结果表明,流域多年平均侵蚀强度4399.79t/(km2·a),属中... 详细信息

对基于上坡汇流面积的坡长因子算法进行改进,提出考虑上坡土地利用/覆盖对汇流影响的坡长因子算法,运用GIS和RUSLE评估黄土高原四面窑沟流域的土壤侵蚀强度及其与环境因素的关系。结果表明,流域多年平均侵蚀强度4399.79t/(km2·a),属中度侵蚀;侵蚀强度和侵蚀量均随坡度增加而显著增加,80.59%的侵蚀量来源于占流域总面积59.06%的25°以上坡度带;不同坡向的侵蚀强度表现为正阳坡>半阳坡>半阴坡>正阴坡,其中,占总面积45.07%的阳坡产生56.50%的侵蚀量;不同土地利用类型中,占总面积57.07%的草地产生96.37%的侵蚀量,成为目前流域内主要侵蚀产沙源。研究为应用修正通用土壤流失方程在黄土高原进行侵蚀评估提供技术范例,为该区侵蚀防治和水土资源利用提供有益参考。

关键词：土壤侵蚀地理信息系统修正通用土壤流失方程黄土高原

Study on the Influence of Environment Vulnerability in the Northwest Yunnan

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Asian Agricultural Research 2013年第12期5卷 77-79,85页

作者： Zhaorong OU qingke zhu Guangjing BAO Xiaoyun YANG School of Ecotourism Southwest Forestry University School of Water and Soil Conservation Beijing Forestry University School of Urban and Environment Yunnan University of Finance and Economics

With the deterioration of the global ecology,the eco-environment fragility has been an important topic of the ecological environment *** Northwest Yunnan is a typical area of abundant biological resources and vulnerable ecological *** ecological environment vulnerability is more initiated by the human disturbances except its special natural basic factors such as the geological structure,the terrain,the geomorphology,the climate and hydrology conditions and so *** paper analyses the human disturbances factors which impress the ecological environment vulnerability of the region from the negative interferences and positive interferences in order to enhance the research of the ecological environment to protect the ecological environment better in this area.

关键词： Human disturbance the Northwest Yunnan Ecological

20世纪中期以来不同时段黄河年输沙量对水土保持的响应

维普期刊数据库评论

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中国水土保持科学 2019年第5期17卷 1-8页

作者：李敏朱清科水利部黄河水利委员会黄河上中游管理局西安710021 北京林业大学林业生态工程教育部工程研究中心北京100083

黄河年输沙量作为黄河中游黄土高原地区水土流失的载体,在水土流失治理薄弱状态下平均约16亿t/a。截止2015年黄河中游黄土高原地区水土流失综合治理措施保存面积达到26万km^2,治理程度超过62%。黄河(龙门、华县、河津、状头) 4站年输沙... 详细信息

黄河年输沙量作为黄河中游黄土高原地区水土流失的载体,在水土流失治理薄弱状态下平均约16亿t/a。截止2015年黄河中游黄土高原地区水土流失综合治理措施保存面积达到26万km^2,治理程度超过62%。黄河(龙门、华县、河津、状头) 4站年输沙量之和已有10余年不到5亿t/a,最少年份不到1亿t/a。当前国家把黄河流域黄土高原地区的保护与治理作为重大战略举措,因此,研究黄河年输沙量对水土保持的响应特性与响应程度具有重要的现实意义。笔者选取22个降雨因子和水土流失治理度因子,采用回归分析方法,对1954-2015年黄河4站年输沙量分3个时段进行统计分析。计算结果:1) 1954-1966年时段,仅“河吴区间7-8月降雨量”1个因子可以“解释”该时段年输沙量78%的变化;2) 1967-1987年时段,逐步回归筛选出了由水土流失治理度和3个降雨因子组成的非线性回归模型;3) 1988-2015年时段,仅由“水土流失治理度”1个因子就能够“解释”黄河年输沙量近80%的变化。3个时段计算结果的变化表明,随着水土流失治理度的增加,黄河4站年输沙量对水土保持的响应从不明显到显著。其中:20世纪60年代以前黄河年输沙量对水土保持响应不敏感;20世纪60-80年代,水土保持减少黄河年输沙量的作用显现,黄河年输沙量对水土流失治理程度有所响应,水土流失治理度是造成黄河年输沙量波动递减的主要因子;20世纪80年代中期以后,水土保持减少黄河年输沙量的作用十分显著,黄河年输沙量对水土流失治理程度响应强烈,在水土流失治理度超过60%时,以95%的置信度,黄河年输沙量小于6亿t/a;近期水土保持对黄河年输沙量的减沙量超过10亿t/a。

关键词：年输沙量泥沙黄土高原水土保持减沙黄河

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元谋干热河谷旱季植被覆盖度的时空异质性

林业科学 2017年第11期53卷 20-28页

作者：欧朝蓉朱清科孙永玉西南林业大学地理学院昆明650224 北京林业大学水土保持学院北京100083 中国林业科学研究院资源昆虫研究所昆明650216

【目的】探究2008—2016年元谋干热河谷植被覆盖的时空异质性,分析植被覆盖度变化的原因,为区域植被生态保护提供基础数据和理论依据。【方法】以2008,2010,2012,2014和2016年5期Landsat遥感影像为数据源,以ENVI为技术平台,采用像元二... 详细信息

【目的】探究2008—2016年元谋干热河谷植被覆盖的时空异质性,分析植被覆盖度变化的原因,为区域植被生态保护提供基础数据和理论依据。【方法】以2008,2010,2012,2014和2016年5期Landsat遥感影像为数据源,以ENVI为技术平台,采用像元二分法获取研究区5个时期的研究区植被覆盖度数据,确定植被覆盖度等级和分类标准,利用地理空间分析法研究不同年份植被覆盖度特征,分析各高程带植被覆盖度的构成状况;在Arc GIS支持下提取各年份不同等级植被覆盖度的面积,通过GIS叠置分析获取2008和2016年的植被覆盖度转移矩阵;以与研究区等面积的空间格网对不同年份的植被覆盖度进行空间采样,以多元统计法计算格网点植被覆盖度标准差和回归斜率研究植被覆盖度的时间演变特征。【结果】研究区植被覆盖度以龙川江河谷及金沙江河谷为界表现出东高西低、南高北低,且自河谷坝区向中高山呈现中低—低—中—中高的整体空间格局;5个时段植被覆盖度分别为0.562,0.586,0.494,0.578和0.566;中高山区Ⅰ和Ⅱ级植被覆盖度的区域面积分别占研究区Ⅰ和Ⅱ级植被覆盖度总面积的60%和50%以上,坝周低山区和中低山区Ⅲ和Ⅳ级植被覆盖度的区域面积分别占研究区Ⅲ和Ⅳ级植被覆盖度总面积的70%~80%;河谷区坝区的Ⅴ级植被覆盖度的区域面积占研究区Ⅴ级植被覆盖率总面积的60%以上;8年来不同等级植被覆盖度的转移面积占区域总面积的61.03%,Ⅰ级植被覆盖度中有95.19km2向Ⅱ级植被覆盖度转移;年际间植被覆盖度标准差(SD)为0~0.541,植被覆盖度增加的区域面积和减少的区域面积之比为10∶9,呈显著性减少和显著性增长的区域面积分别占研究区面积的9.132%和6.794%。【结论】干热河谷植被覆盖度空间地带差异明显;植被覆盖度偏低,植被覆盖度等级间转换较为频繁;植被覆盖度年际间变化幅度不大,植被覆盖度呈增长的区域面积略大于减少区域面积,但呈显著性减少的区域面积大于呈显著性增长的区域面积;东部和南部的中高山地带植被覆盖度的结构恶化。应继续强化退耕还林还草、强化天然林保护等措施的力度,降低中高山和中低山的人为干扰强度,在河谷坝区和坝周低山积极开展人工植被恢复工作,促进区域植被生态的可持续发展。

关键词：干热河谷植被覆盖度时空异质性 GIS RS 空间格局年际波动人为干扰