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Responses of vegetation cover to the Grain for Green Program and their driving forces in the He-Long region of the middle reaches of the Yellow River

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Journal of Arid Land 2013年第4期5卷 511-520页

作者： JianXiang liU zhiguang li XiaoPing ZHANG Rui li XianChun liU HanYang ZHANG State Key Laboratory of Soil Erosion and Dryland Farming on Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water Resources Graduate University of Chinese Academy of Sciences Soil and Water Conservation Monitoring Centre the Ministry of Water Resources of the People's Republic of China Workers Sanatorium of the Yellow River

The implementation of the Grain for Green Program is a great breakthrough in the history of China＇s ecological environment construction,which can control soil erosion effectively,increase land productivity and improve the ecological *** investigate the eco-environmental benefits brought by the Grain for Green Program,the spatiotemporal variations of vegetation cover in the growing season from 2000 to 2010 across the Hekou-Longmen （He-Long） region were analyzed by using remote sensing information,meteorological data and land use ***,the impacts of climate and human activities on vegetation change were evaluated *** vegetation cover in the growing season increased very *** vegetation cover occurred in 98.7％ of the region,of which the area for vegetation cover improved slightly constituted 79.8％ of the whole *** moderately improved was mainly distributed in the south of the He-Long region,covering 9.6％ of the area,and the area for vegetation basically unchanged concentrated in the middle and upper reaches of the Wuding *** was found to be an important natural factor influencing vegetation cover *** area of vegetation cover showing a significantly positive correlation with precipitation occupied 22.14％ of the *** driven by policies from the Grain for Green Program,forestland increased significantly and land use structure became more *** activities played a positive and effective role in the protection,restoration and improvement of vegetation in the places where vegetation cover was basically unchanged,even though precipitation declined greatly,and vegetation improved moderately with massive increases of forestland and grassland.

关键词： vegetation cover precipitation land use the Grain for Green Program the He-Long region

Climate change in the Hongliujing area of Lop Nur over the past 200 years revealed by the stable oxygen isotopes of Tamarix cones

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Frontiers of Earth Science 2023年第4期17卷 970-980页

作者： zhiguang li Yaqing DONG Haoyu ZHANG Hongxiao SUN Danyang JIA Shikai SONG Yuanjie ZHAO Hebei Key Laboratory of Environmental Change and Ecological Construction College of Geographical SciencesHebei Normal UniversityShijiazhuang 050024China Hebei Center for Ecological and Environmental Geology Research Hebei GEO UniversityShijiazhuang 050031China

The layers of Tamarix cones within sedimentary deposits in arid regions have significant chronological and paleoenvironmental ***,we compare the δ^(18)O values of Tamarix cones in the Hongliujing area of Lop Nur with meteorological data for the Ruoqiang meteorological station for 1960-2019 *** regression analysis was used to reconstruct the average temperature for April and the precipitation for November in the Hongliujing area over the past 200 *** results showed that the δ^(18)O values were significantly negatively correlated with the temperature for February,April,May,August,December,and with the annual mean temperature;significantly negatively correlated with the precipitation for February and April;significantly negatively correlated with the sunshine hours for March and May;significantly positively correlated with the sunshine hours for February,July,August,October,and December,and with the annual mean values;and significantly correlated with the relative humidity for April,July,August,September,October,and November,and with the annual mean *** on the δ^(18)O record of the past 200 years,the Hongliujing area experienced two warm-wet periods(1874-1932 and 2004-2019 AD)and two cold-dry periods(1832–1873 and 1933-2003 AD).Thus,the climate was characterized by alternating warm-wet and cold-dry *** analysis revealed three main cycles:45 years,29 years,and 14 years.

关键词： Tamarix cones climate change δ^(18)O Lop Nur

A Study on Description Methods of Sediment Transport Modulus in Small Watersheds

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Meteorological and Environmental Research 2021年第5期12卷 50-54页

作者： zhiguang li liyi ZHAO The Center of Soil and Water Conservation Monitoring Ministry of Water ResourcesBeijing 100055China Tianshui Governance and Supervision Bureau of Yellow River Soil and Water Conservation Tianshui 74100Chin

[Objective]This study aimed to clear the advantages,disadvantages and applicability of various analysis methods to assess sediment transport modulus in small watersheds using the multi-year observation data. [Method]Four methods,including the statistical eigenvalues,depolarized arithmetic mean,frequency of erosion intensity and box-whisker plots were applied into calculation of sediment transport modulus in four small watersheds,and then the results of the methods were compared to to filter a method with the widest applicability and scientific validity. [Result] The statistical arithmetic mean and median could hardly represent the concentration and general level of multi-year sediment transport modulus. Although the depolarized arithmetic mean had the tendency of reflecting the general level of data,it lost the extreme value and its information for making decision. The frequency of erosion intensity grade reflected the distribution of data in intensity classification. Box-whisker plot could show the concentration,dispersion and the number of abnormal data. [Conclusion] Multiple methods can be combined to comprehensively and objectively characterize the multi-year sand transport modulus due to their advantages and disadvantages. Additionally,box-whisker plot has good objectivity and applicability in displaying the multi-year data of small watershed.

关键词： Small watershed Sediment transport modulus General situation of many years Description methods Multi-year average Box-whisker plot

江西省首单水土保持生态产品交易价值核算主要做法及探讨

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中国水土保持 2025年第1期 24-28,31,I0005页

作者：李智广涂安国于来会盛菲肖胜生王海燕郑海金水利部水土保持监测中心北京100053 江西省水利科学院江西南昌330029 浙江省水利水电勘测设计院有限责任公司浙江杭州310002

2024年12月10日,江西省上饶市广丰区祝家坞马家柚基地水土保持生态产品交易在南昌签约成交,这是江西省推动水土保持生态产品价值实现的第一单交易,是贯彻落实《关于建立健全生态清洁小流域水土保持生态产品价值实现机制的意见》在全国... 详细信息

2024年12月10日,江西省上饶市广丰区祝家坞马家柚基地水土保持生态产品交易在南昌签约成交,这是江西省推动水土保持生态产品价值实现的第一单交易,是贯彻落实《关于建立健全生态清洁小流域水土保持生态产品价值实现机制的意见》在全国的率先突破,对进一步拓宽“两山”转化的水土保持新路径、推动“两山”理念指导发展水土保持新质生产力提供了实践案例。以本次交易为例,阐述了水土保持生态产品价值核算的主要做法:①研究确定生态产品价值核算基本原则与技术路线;②全面查清项目区概况及水土保持措施现状;③依规研判确定生态产品价值核算指标;④调查研判生态产品功能量与其单价;⑤核算生态产品价值量。为增加生态产品价值核算的科学性和可靠性,提升生态产品价值市场化实现程度,在下一步工作中应注意坚持合规性、客观性、可比性的原则,全面调研掌握项目实际情况,分析和确定生态产品类型及其价值核算的指标与功能量、单价,保证核算所得价值量科学、合理。

关键词：水土保持生态产品价值核算 “两山”转化江西省

The assessment of soil loss by water erosion in China

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International Soil and Water Conservation Research 2020年第4期8卷 430-439页

作者： Baoyuan liu Yun Xie zhiguang li Yin liang Wenbo Zhang Suhua Fu Shuiqing Yin Xin Wei Keli Zhang Zhiqiang Wang Yingna liu Ying Zhao Qiankun Guo Faculty of Geographical Science Beijing Normal UniversityBeijing100875China Soil Conservation Monitoring Centre Ministry of Water Resources of People's Republic of ChinaBeijing100053China Institute of Soil Science Chinese Academy of SciencesNanjing210008China China Institute of Water Resources and Hydropower Research Ministry of Water Resources of People's Republic of ChinaBeijing100038China

Soil erosion is a major environmental problem in *** for soil erosion control requires accurate soil erosion rate and spatial distribution *** aim of this article is to present the methods and results of the national soil erosion survey of China completed in 2011.A multi-stage,unequal probability,systematic area sampling method was employed.A total of 32,948 sample units,which were either 0.2-3 km2 small catchments or 1 km2 grids,were investigated on *** erosion rates were calculated with the Chinese Soil Loss Equation in 10 m by 10 m grids for each sample unit,along with the area of soil loss exceeding the soil loss tolerance and the proportion of area in excess of soil loss tolerance relative to the total land area of the sample *** were created by using a spatial interpolation method at national,river basin,and provincial *** showed that the calculated average soil erosion rate was 5 t ha-1 yr-1 in China,and was 18.2 t ha-1 yr-1 for sloped,cultivated *** soil erosion occurred on cropland,overgrazing grassland,and sparsely forested *** proportions of soil loss tolerance exceedance areas of sample units were interpolated through the country in 250 m *** national average ratio was 13.5%,which represents the area of land in China that requires the implementation of soil conservation *** survey results and the maps provide the basic information for national conservation planning and policymaking.

关键词： National soil erosion survey CSLE Sample units Chinese soil loss map Soil erosion rate Ratio of soil erosion area

Novel patterns of cancer genome evolution

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Oncology and Translational Medicine 2015年第5期1卷 222-225页

作者： Xia Zhang Xiaodi Deng Yu Zhang zhiguang li Institute of Cancer Stem Cell Second Affiliated HospitalCancer CenterDalian Medical University

Cells usually undergo a long journey of evolution during the progression from normal to precancerous cells and finally to full-fledged cancer cells. Multiple genomic aberrations are acquired during this journey that could either act as drivers to confer significant growth advantages or act as passengers with little effect on the tumor growth. Recent advances in sequencing technology have made it feasible to decipher the evolutionary course of a cancer cell on a genome-wide level by evaluating the relative number of mutated alleles. Novel terms such as chromothripsis and chromoplexy have been introduced to describe the newly identified patterns of cancer genome evolution. These new insights have greatly expanded our understanding of the initiation and progression of cancers,which should aid in improving the efficiency of cancer management and treatment.

关键词： Cancer genome evolution chromothripsis chromoplexy

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一类非线性拋物变分不等式解的存在性

应用数学学报 2019年第4期42卷 550-563页

作者：李志广山西大同大学数学与计算机科学学院

本文研究了一类基于非线性抛物算子的变分不等式问题.首先,通过拓展偏微分方程的弱解理论定义了变分不等式的弱解.其次,利用惩罚函数并结合连续方法,证明了变分不等式存在弱解.

关键词：非线性抛物变分不等式弱解惩罚方法存在性

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陕南嘉陵江流域土石山地综合利用研究

水土保持通报 1998年第4期18卷 42-45页

作者：李智广李锐中国科学院水土保持研究所

在分析陕南嘉陵江流域重点防治区水土保持治理前后土地利用结构变化及其成效的基础上，探讨了该区土地利用的方向和具体措施。认为，欲兼顾提高土地生产力、发展经济和保护环境，土地利用调整的方向应为：狠抓坡改梯，兴修基本农田；退... 详细信息

在分析陕南嘉陵江流域重点防治区水土保持治理前后土地利用结构变化及其成效的基础上，探讨了该区土地利用的方向和具体措施。认为，欲兼顾提高土地生产力、发展经济和保护环境，土地利用调整的方向应为：狠抓坡改梯，兴修基本农田；退耕还林，发展经果林；综合利用资源，多种经营综合开发。在具体操作时，坚持开展以小流域为单元的综合治理和综合开发，并合理利用荒山荒坡，提高土地利用率。

关键词：土石山地陕南土地利用水土保持山地

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小流域治理综合效益评价方法刍议

水土保持通报 1998年第5期18卷 19-23页

作者：李智广李锐中国科学院

结合实例分析了国内小流域治理综合效益评价主要定量方法（包括加权综合指数法、加乘综合指数法和关联度分析法）的原理、适应性及其局限性。分析表明：３种方法的评价结论基本一致，加乘法比加权法有较高的灵敏度。认为应用ＧＩＳ技术... 详细信息

结合实例分析了国内小流域治理综合效益评价主要定量方法（包括加权综合指数法、加乘综合指数法和关联度分析法）的原理、适应性及其局限性。分析表明：３种方法的评价结论基本一致，加乘法比加权法有较高的灵敏度。认为应用ＧＩＳ技术，从定量和定位两方面评价治理措施及其功能将成为今后治理评价的发展趋势。

关键词：小流域治理评价法综合效益水土保持