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| 1 | Global understanding of farmland abandonment: A review and prospects显示文摘自从 1950 年代,引人注目的农田放弃在许多发达国家和一些发展中的国家一直在发生。这全球陆地使用现象根本上改变了广泛的农村风景。在驾驶变化的机制影响和后果政策回答发现了下列的陆地使用的标题下面的全球农田放弃的评论:(1 ) 农田放弃在欧洲和北美洲首先在发达国家发生了,但是放弃的程度显著地变化了。(2 ) 改变社会经济的因素是为农田放弃的主要驱动力。并且陆地 marginalization 是原因,它由于耕作机会的激烈的增加花费了的基础,当为放弃的直接因素是时,农业劳动的精神病医生强迫。(3 ) 是否沉溺于什么程度和它的空间分布在村庄,家庭和包裹规模最后依赖于从物理条件,劳动者属性,耕作和地区性的社会经济的条件的综合效果。与东方欧洲的例外,农田放弃是更可能的发生在多山、多山的区域,由于他们的相反的耕作条件。(4 ) 农田放弃的研究应该集中于它的生态、环境的效果,当时它更积极或更否定仍然在争论。(5 ) 增加农业津贴将对减缓农田放弃的率传导性,但是这不是需要被实现的唯一的措施。由于瓷器快速的都市化,有高可能性,放弃的率在不久的将来将增加。然而,很,很少研究都没在中国集中于这个快速的陆地使用趋势,并且,作为结果,有动态机制的不适当的理解和这现象的后果。这篇论文由在中国为进一步的研究建议一些未来方向得出结论。这些方向包括监视地区性、国家的放弃动力学,分析趋势,估计风险和农田放弃的社会经济的效果,并且通知政策做。 | LI Shengfa LI Xiubin | 2017 | Journal of Geographical Sciences2017，27，9： | 33 |
| 2 | Records of the East Asian winter monsoon from the mud area on the inner shelf of the East China Sea since the mid-Holocene显示文摘AMS14C dating and analysis of grain size,major elements and clay minerals were applied to Core MZ01 from the mud area on the inner shelf of the East China Sea.Based on the environmentally sensitive grain size,clay mineral and major element assemblages,the history of the East Asia winter monsoon since the mid-Holocene could be reconstructed.These three proxies,mean grain size(>9.71μm),chemical index of alteration(CIA)and ratio of smectite to kaolinite in particular,show similar fluctuation patterns. Furthermore,10 extreme values corresponding to the contemporary cooling events could be recognized since the mid-Holocene;these extreme values are likely to have been caused by the strengthening of the East Asia winter monsoon.The cooling events correlated well with the results of theδ18O curves of the Dunde ice core and GISP2,which therefore revealed a regional response to global climate change.Four stages of the East Asia winter monsoon were identified,i.e.8300-6300 a BP,strong and unstable;6300-3800 a BP,strong but stable;3800-1400 a BP,weak and unstable;after 1400 a BP,weak but stable. | LIU ShengFa SHI XueFa LIU YanGuang QIAO ShuQing YANG Gang FANG XiSheng WU YongHua LI ChaoXin LI XiaoYan ZHU AiMei GAO JingJing | 2010 | Chinese Science Bulletin2010，55，21： | 25 |
| 3 | Clay mineral composition and their sources for the fluvial sediments of Taiwan Residents rivers显示文摘Located at the collision boundary between the Philippine Sea Plate and the Eurasian Continental Plate,the island of Taiwan is generally recognized as an important example in the MARGINS Program Science Plan and 'source-to-sink' research because of its high tectonic activity,heavy rainfall and unique geography.Large suspended sediment loads are transported to the adjacent ocean by Taiwan Residents rivers every year,making Taiwan an important source of sediments into the adjacent seas and a natural laboratory for studying the systemic movement of fluvial sediments from source to sink.A detailed study on the clay mineral composition of surface sediments collected from the drainage basins of 12 Taiwan Residents rivers using X-ray diffraction methods was conducted.Our results indicated that the clay mineral assemblages consisted dominantly of illite(approximately 73%) and chlorite(approximately 24%),with lesser abundances of kaolinite(approximately 3%) and even lower levels of smectite from the Danshuei River sediments in northwestern Taiwan.The Jhuoshuei River sediments from western Taiwan contained clay mineral assemblages that consisted of illite(approximately 75%) and chlorite(approximately 25%),but they lacked kaolinite and smectite.In southwestern Taiwan,the clay mineral assemblages were dominated by illite(approximately 75%) and chlorite(approximately 23%),but had a low abundance of kaolinite(generally < 2%) and no smectite.The clay mineral assemblages in eastern Taiwan are obviously different from those in western parts of the island.The most noticeable difference is that the average abundance of chlorite in the Hualien River from eastern Taiwan was the highest(approximately 48%) of all the Taiwan Residents rivers.We concluded that,in general,the clay mineral assemblages in Taiwan Residents rivers were mainly composed of illite and chlorite with kaolinite and smectite being scarce,and these trends are different from those in China's mainland rivers.The clay mineral composition shown in this study was primarily determined by the properties of the bedrock,and the differential weathering intensities of the drainage area.The surface sediments in Taiwan's rivers showed a greater abundance of illite and chlorite because the outcropped rocks were mainly composed of Tertiary sedimentary rocks,especially sandstone,shale and slate,and show strong physical weathering.The relatively high relief and more abundant rainfall also caused the clay minerals in the fluvial sediments to be transported to the estuaries down rivers from the mountains and then delivered to the adjacent seas by currents and waves over a shorter time scale. | LI ChuanShun SHI XueFa KAO ShuhJi CHEN MinTe LIU YanGuang FANG XiSheng LUE HuaHua ZOU JianJun LIU ShengFa QIAO ShuQing | 2012 | Chinese Science Bulletin2012，57，6： | 23 |
| 4 | Major and trace element geochemistry of the mid-Bay of Bengal surface sediments: implications for provenance显示文摘The major and trace elements in 110 surface sediment samples collected from the middle of the Bay of Bengal(mid-Bay of Bengal) are analyzed to investigate provenance. Si levels are highest, followed by Al, and the distributions of these two elements are identical. The average CIA*(chemical index of alteration) value is 72.07,indicating that the degree of weathering of the sediments in the study area is intermediate between those of sediments of the Himalayan and Indian rivers. Factor analyses and discrimination function analyses imply that the two main provenances are the Himalayan and the Indian continent. The inverse model calculation of the Tinormalized element ratios of the Bay of Bengal sediments indicate an estimated average contribution of 83.5%and 16.5% from the Himalayan and peninsular Indian rivers to the study area, respectively. The Himalayan source contributes more sediment to the eastern part of the study area, whereas the western part receives more sediment from the Indian Peninsula than did the eastern part. The primary mechanisms for deposition of sediments in the study area are the transport of Himalayan matter by turbidity currents and river-diluted water and the transport of Indian matter to the study area by a surface circulation in the Bay of Bengal, particularly the East India Coastal Current. | LI Jingrui LIU Shengfa FENG Xiuli SUN Xingquan SHI Xuefa | 2017 | Acta Oceanologica Sinica2017，36，3： | 12 |
| 5 | Field measurements of settling velocities of fine sediments in Three Gorges Reservoir using ADV显示文摘The Three Gorges Reservoir(TGR) is suffering from unexpected fine sediment deposition,to better understand the fine sediment transport processes,field measurements were conducted at the Zhongxian and Fengjie reaches.A method based on the sediment diffusion equation was proposed to measure the settling velocities using the Acoustic Doppler Velocimeter(ADV).The backscatter acoustic intensities(BSI) received from the ADV were calibrated against the sediment concentrations measured via water sampling,suggesting a linear relationship in double logarithmic coordinate system.The instantaneous sediment concentration was calculated using the derived relationship,and then the settling velocity was obtained through the proposed procedure.The settling velocities of the fine particles in the TGR were found to vary with the water depth.Most of the effective settling velocities were within the range of 0.1-10 mm/s,which were larger than those of the primary particles,indicating that the flocculation was likely to occur in the TGR.Additionally,it is suggested that the turbulent motion played an important role in the flocculation in the TGR. | Wenjie Li Shengfa Yang Jiang Hu Xuhui Fu Peng Zhang | 2016 | International Journal of Sediment Research2016，31，3： | 6 |
| 6 | Distribution of major and trace elements in surface sediments of Hangzhou Bay in China显示文摘The Inductively Coupled Plasma Optical Emission Spectrometer was used to analyze sediment samples collected from the Hangzhou Bay to determine major and trace elemental concentrations. Based on these concentrations, the study area can be classified into three geochemical provinces. Province I covers the northern Hangzhou Bay area and contains high concentrations of Al_2 O_3 , Fe_2 O_3 , MgO, Na_2 O, K_2 O, MnO, Cr, Cu, Ni, Pb, V, Co and Zn. Province III is located in the western Hangzhou Bay, near the Qiantang River mouth, and contains high concentrations of SiO_2 , Na_2 O, P_2 O_5 , TiO_2 , Cr, Sr, Zr. Province II is located in the middle and eastern Hangzhou Bay, with the medium concentrations of major and trace elements. The results also demonstrate that the grain size is the dominating factor controlling the spatial variations of elemental concentrations, and the Changjiang River (Yangtze River) and Qiantang River sediments play an important role in the distribution of these elements. Anthropogenic impact on heavy metal concentrations (especially Cr, Sr and Zr) can be detected in the surface sediments near the Qiantang River mouth. | LIU Shengfa LIU Yanguang YANG Gang QIAO Shuqing LI Chaoxin ZHU Zhiwei SHI Xuefa | 2012 | Acta Oceanologica Sinica2012，31，4： | 5 |
| 7 | The mechanism of farmland marginalization in Chinese mountainous areas:Evidence from cost and return changes显示文摘Farmland marginalization has become the main trend of Iand-use change in the mountainous areas of China.Using annual survey data of major agricultural production costs and earnings at national and provincial levels in China,this study aims to analyze the reasons and mechanism behind farmland marginalization in mountainous areas.We find that farmers on plains are able to reduce their per mu labor input effectively through in tensive use of agricultural machinery,which has minimized the impact of the increase in labor price.However,it is extremely challenging for farmers in mountainous areas to use the same method owing to the rough terrain.Thus,per laborer farming area in these areas has increased relatively slowly,causing a widening gap in agricultural labor productivity between the two regions.With the rapid rise in labor costs since 2003,the marginalization of cultivated land in mountainous areas is evident.In 2013,the net profit of agricultural production in mountainous China fell below zero.Since 2000,the Iand-use and land?cover change in these areas was characterized by the reduction of farmland area,reforestation,and the enhancement of the NDVI value.The high correlation between the NDVI change rate and the ratio of change in farmland(r=-0.70)and forest(r=0.91)in mountainous areas at provincial level further attests to the trend of farmla nd margi nalization there.Fin ally,we summarize the mecha nism of such marginalization against the backdrop of the rapid increase in the opport unity cost of farming and the rapid fall of agricultural labor forces in mountainous areas.This study contributes to a deep understanding of the development process of farmland marginalization and abandonment as well as forest transition in Chinese mountainous areas. | LI Shengfa LI Xiubin | 2019 | Journal of Geographical Sciences2019，29，4： | 4 |
| 8 | Estimating instantaneous concentration of suspended sediment using acoustic backscatter from an ADV显示文摘The measurement of instantaneous sediment concentration remains a challenging task. In this study, a three-step procedure is proposed to estimate instantaneous sediment concentration using acoustic backscatter from Acoustic Doppler Velocimeter (ADV). The influences of acoustic noise and particle diameter on an ADV's performance was first tested in the laboratory, then the three-step procedure was verified based on field measurements in the Zhongxian and Fengjie reaches in the Three Gorges Reservoir. The first step involves reconstructing the backscatter signal time series. Due to contamination from both the noise floor and spurious spikes, the denoising-despiking method was applied instead of the traditional velocity-despiking methods, and this approach performed well based on spectrum ana-lysis. The second step involves calibrating the sediment concentration against the backscatter signal. A linear relation, whose slope and intercept were calibrated to be dependent on particle diameter, is proposed in double logarithmic coordinates. The third step involves calculating the instantaneous sediment concentration using reconstructed instantaneous backscatter based on the proposed relation. The accuracy of the proposed method was evaluated through consideration of the concentration spec-trum and sediment flux, indicating that the proposed three-step procedure is effective for the mea-surement of instantaneous sediment concentration. | Wenjie Li Shengfa Yang Wei Yang Yi Xiao Xuhui Fu Shuaishuai Zhang | 2019 | International Journal of Sediment Research2019，34，5： | 2 |
| 9 | Rolling coating technology of high transparent and low square resistance显示文摘 | Hu Yunhui Li jingzeng Yu Shengfa | 2001 | Vacuum Technology and Application2001，，2： | 1 |
| 10 | Deter- mining the Existence of the Fine Sediment Floccula- tion in the Three Gorges Reservoir显示文摘 | Li Weniie Wang Jie Yang Shengfa | 2015 | Journal of Hydraulic Engineering2015，14，05： | 1 |
| 11 | Gravel excavation and geomorphic evolution of the mining affected river in the upstream reach of the Yangtze River,China显示文摘As economic development upstream in the Yangtze River basin has progressed in recent decades,the demand for sediment has rapidly increased and contributed to an expansion in sediment excavation that may affect the river's stability and navigation safety.In the current study,the distribution of gravel mining in the upstream reach of the Yangtze River was investigated using field measurements obtained from 2008 to 2017.An experimental investigation was then done to analyze the bed load behavior in a typical mined channel using a physical river model.Finally,a two-dimensional hydrodynamic-sediment transport numerical model was developed to predict the evolution of the mined channel.The results indicate that gravel mining was mainly distributed among the following nine river sections:Tongluoxia-Yibin,Erlong-Xianglutan,Naxi-Jinkou,Binpangqi-Hongyanqi,Chayuqi-Shenbeizui,Yangshipan-Shangbaisha,Dongxikou,Baisha-Wenzhongba,and Jiangjin-Shenzhongba.The gravel shoals near the riverbank have been destroyed,and the bed topography has been altered by up to 1.65×10^(9)m^(3)over the past 10 years.A bed load velocity formula was proposed to describe bed load transport in the mined channel based on dimensional analysis.The recovery process of the excavation pits was slow in both the experiments and simulations,with only 0.12%and 1.39%,respectively,of the mined amounts of gravel being restored.Finally,the recovery rate of the mining pits gradually slowed as the sediment supply from upstream decreased,suggesting that the destroyed gravel shoals rarely returned to their original forms due to the combined operation of hydro-projects in upstream areas and limited sediment storage in the channel. | Yi Xiao Wenjie Li Shengfa Yang | 2022 | International Journal of Sediment Research2022，37，2： | 0 |
| 12 | Extent and spatial distribution of terrace abandonment in China显示文摘Driven by urbanization and industrialization,arable land in hilly and mountainous regions of China is gradually becoming marginalized,with the extent of arable land abandonment rapidly expanding from poor-quality sloping arable land to high-quality terraces.The abandonment of large-scale terraces will lead to a series of socio-economic and ecological effects.A national sample survey was used to investigate the extent and spatial distribution of terrace abandonment in China,and a total of 560 valid village questionnaires from 329 counties were collected in the mountainous areas of China.The main findings are as follows:(1)The phenomenon of terrace abandonment was widespread throughout the country,with 54% of the total surveyed villages exhibiting terrace abandonment,and the area of abandoned terraces accounting for 9.79% of the total.(2) The degree of terrace abandonment is high in the south and low in the north.The most serious region with abandonment was the hilly and mountainous areas in the south,especially in the middle and lower Yangtze River region.(3)The main driving factors of terrace abandonment were rural labor migration,agricultural mechanization level,irrigation conditions,and transportation conditions for cultivation.Targeted measures should be taken based on the specific conditions of each area to alleviate terrace abandonment.Measures such as improving terrace mechanization are universally applicable.Specifically,low-quality terraces can be withdrawn orderly,and for high-quality terraces,multiple measures are needed to consolidate agricultural production,such as adjusting the planting structure,strengthening agricultural infrastructure construction,and encouraging the transfer of land-use rights as well as large-scale operation. | DONG Shijie XIN Liangjie LI Shengfa XIE Hualin ZHAO Yuluan WANG Xue LI Xiubin SONG Hengfei LU Yahan | 2023 | Journal of Geographical Sciences2023，33，7： | 0 |
| 13 | Self-similarity of spanwise rotational motions’population trends in decelerating open-channel flow显示文摘Decelerating open-channel flow is a type of flow that gradually moves forward with decreasing velocity and increasing water depth.Although all flow parameters change along the streamwise direction,previous studies have revealed that these parameters’vertical distributions at different sections can be universally described with a single profile when being nondimensionalised by appropriate scales.This study focuses on the population trends of spanwise rotational motions at various sections along the main flow direction by particle imaging velocimetry(PIV)measurement.The wall-normal population distributions of density,radius,swirling strength,and convection velocity of the prograde and retrograde motions show similar trends in uniform open-channel flows.The dimensionless representation is invariant along the main flow direction.This study’s results indicate the self-similar characteristic of population trends of spanwise rotational motions prevails in decelerating open-channel flow. | Peng Zhang Yanchong Duan Qiang Zhong Danxun Li Shengfa Yang Jiang Hu Wenjie Li | 2022 | Theoretical & Applied Mechanics Letters2022，12，3： | 0 |
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