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喀斯特峰丛坡地灌木林地与梯田旱地土壤水分入渗特征 被引量:33
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作者 徐勤学 李春茂 +3 位作者 陈洪松 付智勇 吴攀 王克林 《农业工程学报》 EI CAS CSCD 北大核心 2018年第8期124-131,共8页
为明确喀斯特峰丛坡地土壤的入渗特性,该文测定了灌木林地和梯田旱地不同土层的入渗过程,同时分析了影响入渗的因素,并用不同入渗模型对其过程进行拟合。结果表明:(1)梯田旱地的入渗性能低于灌木林地,其平均入渗系数约是灌木林地的78.6%... 为明确喀斯特峰丛坡地土壤的入渗特性,该文测定了灌木林地和梯田旱地不同土层的入渗过程,同时分析了影响入渗的因素,并用不同入渗模型对其过程进行拟合。结果表明:(1)梯田旱地的入渗性能低于灌木林地,其平均入渗系数约是灌木林地的78.6%,尤其在土层30~60 cm的平均初渗率、稳渗率仅为灌木林地的4.3%和4.4%,存在明显的入渗隔层,其原因是梯田旱地本身的土壤黏粒含量充足,加上人为翻耕促使较细颗粒向下移动后堆积。(2)灌木林地土壤中的砂粒含量和有机质含量较高,孔隙度较大,不同土层间的性质差异较小,而梯田旱地0~30 cm与30~60 cm土层的土壤性质差异明显,表现为下层土壤容重大、土壤孔隙度小。两者入渗性能均与土壤容重、孔隙度的相关性极显著(P<0.01)。(3)Horton模型对灌木林地和梯田旱地的拟合效果较好(R2>0.9),且对梯田旱地表层和深层的拟合度比对灌木林地的拟合度更好。Kostiakov模型和Philip模型的拟合效果较差。该文为喀斯特土壤水分管理及土壤入渗模拟提供了理论依据。 展开更多
关键词 土壤水分 入渗 模型 梯田 喀斯特
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医学人文与临床医学结合的若干构想——广州医学专业与医学人文结合研讨会的倾听与思考 被引量:22
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作者 杜治政 赵明杰 《医学与哲学(A)》 CSSCI 北大核心 2009年第6期1-5,共5页
回归人文是当代医学的迫切课题。克服当代医学人性冷漠的缺陷,从根本上说,必须实现生物医学模式到生物-心理-社会医学模式的转变,变革现行的医疗思想,同时为医学与人文的结合提供对话与交流的平台,提高医师的人文素养与人文执业能力。
关键词 回归人文 转变医疗思想 平台
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差分GPS方法在城市活断层探测中的应用探讨 被引量:17
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作者 张军龙 田勤俭 +2 位作者 李智敏 任治坤 郝凯 《地震》 CSCD 北大核心 2007年第3期74-82,共9页
使用差分GPS方法,测量西宁盆地内部各级阶地参数,对比野外阶地特征,探讨区域新构造时期活动特征,以及西宁城市周缘活断层的分布及活动特征。通过这一区域的实践,认为DGPS方法能够快速、精确的获得区域内阶地面的坐标和高程,是确定弱活... 使用差分GPS方法,测量西宁盆地内部各级阶地参数,对比野外阶地特征,探讨区域新构造时期活动特征,以及西宁城市周缘活断层的分布及活动特征。通过这一区域的实践,认为DGPS方法能够快速、精确的获得区域内阶地面的坐标和高程,是确定弱活动或隐伏断裂的可行方法。南川河断裂错断T3、T4、T5阶地,断裂的活动时间为T3阶地形成后,T2级阶地形成前的0.10 Ma B.P.至0.05 Ma B.P.。垂直断距15~20 m,最小垂直活动速率约为0.30mm/a。 展开更多
关键词 DGPS方法 活断层 阶地 西宁地区
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Values and Conservation of Honghe Hani Rice Terraces System as a GIAHS Site 被引量:17
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作者 张永勋 闵庆文 +1 位作者 焦雯珺 刘某承 《Journal of Resources and Ecology》 CSCD 2016年第3期197-204,共8页
Agri-cultural Heritage Systems(AHS) have not only various values but also important enlightening roles for modern agriculture.With agro-scientific and technological progress,the traditional agriculture that has last... Agri-cultural Heritage Systems(AHS) have not only various values but also important enlightening roles for modern agriculture.With agro-scientific and technological progress,the traditional agriculture that has lasted for thousands of years is declining gradually,thus is attached the importance of exploring and protecting our AHS.As a traditional agricultural system for 1300 years,the Honghe Hani Rice Terraces System(HHRTS) has many significant characteristics such as beautiful landscapes,distinctive rice varieties,ecologically clean agricultural production systems,systematic methods of managing water and soil and special ethnic culture.It was designated successively as a Globally Important Agricultural Heritage System(GIAHS) in 2010 and as a World Heritage(WH) in 2013.In this paper,taking HHRTS as an example,we analyzed the economic,ecological,aesthetic,cultural,and social values,as well as the research values,of the GIAHS.We conclude that the restrictions on increasing peasant earnings and improving their living standards are difficult with the low efficiency of traditional planting patterns and the single-industry structure of farming in rugged terrain.However,these restrictive factors are beneficial for developing some industries like green agriculture,organic agriculture or ecological food production because of the clean farmland environment.In the end,we propose the basic approaches to protect the Hani terraces agriculture system should include the local governments to encourage the development of ecotourism,organic agriculture and featuring agriculture by multi-mode economic compensation.It is very important for protecting terraces to coordinate benefits among corporations,governments and villagers by making reasonable policies of compensation. 展开更多
关键词 Honghe Hani Rice terraces System Globally Important Agricultural Heritage Systems(GIAHS) cultural landscape multiple values eco-cultural compensation
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Transportation Accessibility of Central Towns in Important Agricultural Heritage Systems Sites in Mountainous Areas and Its Impact on Local Economic Development: A Case Study of Honghe Hani Rice Terraced System, Yunnan 被引量:12
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作者 ZHANG Yongxun LI Xiande MIN Qingwen 《Journal of Resources and Ecology》 CSCD 2019年第1期29-38,共10页
Transportation as a means to support industrial development can impact the economic development of important agricultural heritage sites. Because the central towns in mountainous areas have weak economic interactions ... Transportation as a means to support industrial development can impact the economic development of important agricultural heritage sites. Because the central towns in mountainous areas have weak economic interactions with each other, an appropriate method is needed to evaluate their transportation accessibility. This paper takes the Honghe Hani Rice Terraced System(HHRTS) as a study area and develops a model to determine shortest time-distances from central towns in the study area to the nearest high-grade city as a way to evaluate transportation accessibility(TA). We then analyze the relationship between the accessibility of these towns and their economies. The study finds that the TA of the central towns in HHRTS is not good as a whole. More than 70% of the towns are more than 1 hour away from their nearest high-grade city. Of the four counties in the study area, Yuanyang County has the best traffic conditions, while Lvchun County has the worst traffic conditions. The central towns in the northern and middle regions have better TA than those in the west, southwest and east margin regions. The small-scale rural economy has little dependence on the transportation network, while secondary industries are obviously impacted by the transportation network. In the future, to support the integrated development of industries in HHRTS, traffic conditions in each town should be improved appropriately according to the industrial orientation of the town, but excessive investments to construct roads irrespective of eco-environmental impacts and economic benefits should be avoided. Especially in the case of ecologically vulnerable towns, the building high-grade roads should be banned. 展开更多
关键词 transportation accessibility rural economy agricultural heritage systems Hani terraces
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北天山山前安集海河阶地形成的时代及意义 被引量:10
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作者 王永 王彦斌 《地质论评》 CAS CSCD 北大核心 2000年第6期584-587,共4页
北天山山前几条主要河流普遍发育河谷阶地。安集海河发育6~8级阶地,通过年代测定及区域对比,可得出安集海河阶地形成于中更新世晚期—晚更新世早期(约12~14万年左右)。第四纪以来构造活动及气候变化控制着河流下切和侧蚀作用的进行,... 北天山山前几条主要河流普遍发育河谷阶地。安集海河发育6~8级阶地,通过年代测定及区域对比,可得出安集海河阶地形成于中更新世晚期—晚更新世早期(约12~14万年左右)。第四纪以来构造活动及气候变化控制着河流下切和侧蚀作用的进行,安集海河阶地的形成和发育明显受第四纪晚期构造活动和气候变化等因素的影响。 展开更多
关键词 安集海河 北天山 河谷阶地 构造活动 气候变化
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基于GRID-TIN混合格网DEM的旱作梯田数值模拟模型研究 被引量:8
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作者 赵卫东 周弯 +2 位作者 汤国安 马雷 赵纪堂 《地理与地理信息科学》 CSCD 北大核心 2015年第3期38-43,共6页
旱梯田地形具有独特的平面和剖面形态特征,现有DEM难以对其地貌形态特征进行准确描述,无法满足构建旱梯田地形数值模拟模型的需求。为此,以黄土高原典型旱梯田地形为切入点,基于Grid-TIN混合格网DEM和面向对象技术构建出水平梯田等典型... 旱梯田地形具有独特的平面和剖面形态特征,现有DEM难以对其地貌形态特征进行准确描述,无法满足构建旱梯田地形数值模拟模型的需求。为此,以黄土高原典型旱梯田地形为切入点,基于Grid-TIN混合格网DEM和面向对象技术构建出水平梯田等典型旱梯田数值模拟模型。根据旱梯田地形的独特地貌形态特征,提出能够对旱梯田地形的高程、坡度进行准确计算的数字地形分析方法。该研究成果是对基于DEM的旱梯田地形数值模拟模型研究的有益尝试,对于探讨利用DEM实现旱梯田地形的有效数字表达与分析具有重要理论意义。 展开更多
关键词 梯田 梯田模型 地形分析 数值模拟
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Spatial Variability Analysis of Soil Nutrients Based on GIS and Geostatistics:A Case Study of Yisa Township, Yunnan, China 被引量:10
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作者 李静 闵庆文 +3 位作者 李文华 白艳莹 Dhruba Bijaya G.C. 袁正 《Journal of Resources and Ecology》 CSCD 2014年第4期348-355,共8页
Hani rice terraces system is one of the Globaly Important Agricultural Heritage Systems (GIAHS) pilot sites selected by FAO. Soil nutrients are an important symbol of soil fertility, and play an important role in th... Hani rice terraces system is one of the Globaly Important Agricultural Heritage Systems (GIAHS) pilot sites selected by FAO. Soil nutrients are an important symbol of soil fertility, and play an important role in the sustainable utilization of land. Based on geo-statistics and GIS, the spatial variation of pH, organic matter, total nitrogen, alkaline hydrolyzable nitrogen, available phosphorus and available potassium in the soil in Yisa (a town in Honghe County, Yunnan Province) was studied. The results show that the spatial variability of pH, organic matter, total nitrogen, alkaline hydrolyzable nitrogen and available potassium exhibited medium spatial variability, and the coefficients of variation are 12.54%, 40.14%, 40.00%, 34.89%, and 40.00% respectively. Available phosphorus exhibited strong spatial variability, and the coefifcient of variation is 102.13%. The spatial variation of pH, organic matter, total nitrogen, alkaline hydrolyzable nitrogen and available potassium fit the index mode, however, the spatial variation of available phosphorus ifts the spherical model. Total nitrogen, available phosphorus and available potassium were greatly affected by soil structural factors, while pH, organic matter and alkaline hydrolyzable nitrogen were affected by both structural and random factors. The spatial distribution of soil nutrients in Yisa was intuitively characterized by Kriging interpolation. It is very important to understand the spatial distribution of soil nutrients, which wil provide the guidance for adjusting agricultural management measures such as fertilization. 展开更多
关键词 spatial analysis geo-statistics soil nutrients KRIGING Hani rice terraces system GIAHS
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紫鹊界梯田区不同土地利用类型土壤入渗特征研究 被引量:10
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作者 王辉 杨小宝 +2 位作者 田大作 吴凤平 陈龙 《灌溉排水学报》 CSCD 北大核心 2012年第5期123-126,139,共5页
采用压力仪和盘式入渗仪测定了紫鹊界梯田区域不同土地利用类型土壤的水分入渗特征并应用多种计算理论推算其水分运移参数。结果表明,林地和退耕地土壤持水能力比旱田和水田强,在相同吸力条件下林地和退耕地的含水率平均比旱田和水田分... 采用压力仪和盘式入渗仪测定了紫鹊界梯田区域不同土地利用类型土壤的水分入渗特征并应用多种计算理论推算其水分运移参数。结果表明,林地和退耕地土壤持水能力比旱田和水田强,在相同吸力条件下林地和退耕地的含水率平均比旱田和水田分别高28%和55%;不同土地利用类型对土壤水分累积入渗量、土壤吸渗率和导水率有着较大的影响,其值均按照林地、退耕地、水田、旱地的顺序依次增大;研究结果初步揭示了紫鹊界土地利用类型对梯田区土壤水分运移机理影响。 展开更多
关键词 盘式入渗仪 土壤吸渗率 导水率 土地利用类型 梯田
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黄土高原现状产沙情势评价 被引量:6
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作者 刘晓燕 《水利学报》 EI CSCD 北大核心 2023年第1期24-33,共10页
在黄河来沙锐减背景下,厘清现状黄土高原在不同降雨情景的年均产沙量,对客观认识黄河未来水沙情势具有十分重要的意义。本文分析了过去60年黄土高原汛期径流及含沙量变化特点,认为该区2010年以来的下垫面可作为现状产沙情势评价的代表... 在黄河来沙锐减背景下,厘清现状黄土高原在不同降雨情景的年均产沙量,对客观认识黄河未来水沙情势具有十分重要的意义。本文分析了过去60年黄土高原汛期径流及含沙量变化特点,认为该区2010年以来的下垫面可作为现状产沙情势评价的代表下垫面。采用理论推算和实际产沙能力分析等两种方法,计算了黄土高原现状下垫面在4种降雨情景下的年均产沙量。结果表明,如果汛期降雨较1956—2019年均值偏丰0~17.3%,2010—2019年下垫面的年均产沙量为3.9亿t a~5亿t a;若基于2018年以来的下垫面,其年均产沙量为3.6亿t a~4.5亿t a;受坝库工程拦截影响,可输送至潼关断面的沙量更少。分析了黄土高原植被和梯田的发展趋势,并考虑流域产沙指数与植被梯田覆盖状况的响应规律,认为该区产沙能力进一步降低的潜力很小。事实上,由于年降雨量450 mm以下地区的新生植被抵御恶劣气候和人类干扰的能力较低,黄土高原产沙量存在反弹至5亿t a~8亿t a的风险。 展开更多
关键词 黄土高原 产沙情势 植被 梯田 降雨
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元江南岸多尺度多民族聚落的空间特征研究 被引量:10
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作者 杨宇亮 罗德胤 孙娜 《南方建筑》 2017年第1期34-39,共6页
元江南岸四县是哈尼、彝、傣、苗、瑶、壮、汉等民族的聚集地,文章在不同尺度下,分别以自然村、行政村、典型个案为研究对象,以GIS的技术方法结合田野调查,探讨多民族聚落的空间特征。主要结论为:多民族聚落在宏观层面具有沿水平方向的... 元江南岸四县是哈尼、彝、傣、苗、瑶、壮、汉等民族的聚集地,文章在不同尺度下,分别以自然村、行政村、典型个案为研究对象,以GIS的技术方法结合田野调查,探讨多民族聚落的空间特征。主要结论为:多民族聚落在宏观层面具有沿水平方向的流域分布、沿垂直方向的垂直分层、沿时间累积的同源聚居3个特征,三者在微观层面中体现为以民族为标识的基本概貌差异,而地域分化、历史机缘与文化交流等因素则加剧了聚落差异的丰富程度,形成了一种民族性与地域性交错的复杂关系,在生产方式与民居细节有着显著表现。 展开更多
关键词 元江 多尺度 多民族 聚落 梯田
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Revisiting Late Quaternary Slip-rate along the Maqu Segment of the Eastern Kunlun Fault, Northeast Tibet 被引量:7
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作者 LI Jian ZHANG Yueqiao +3 位作者 LI Hailong XIONG Jinhong LI Jianhua WU Tairan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第2期486-502,共17页
The Late Quaternary slip rate along the Maqu segment of the eastern Kunlun Fault was estimated using a combination of high-resolution remote sensing imagery interpretation, field observations and differential Global P... The Late Quaternary slip rate along the Maqu segment of the eastern Kunlun Fault was estimated using a combination of high-resolution remote sensing imagery interpretation, field observations and differential Global Positioning System(GPS) measurements of offset river terraces, and 14 C dating of snail shells collected from offset risers. The results show that the left-slip rate along the segment is 3–5 mm/a, and that the vertical slip rate is 0.3–0.5 mm/a. Both the horizontal and vertical slips on the segment remain consistent over a distance of ~100 km. It means that no slip gradient as previously suggested occurred along the Maqu segment, and which thus might behave as an independent seismogenic fault. Judging from multiple relationships among young terrace offsets, we infer that co-seismic surface rupture produced by a characteristic earthquake with a magnitude of Ms7.0–7.5 on the Maqu fault could generate a horizontal slip of 4.5–5 m and a vertical slip of 0.45–0.5 m, with a corresponding ratio(Dh/Dv) of about 9. Two surface rupture events must have occurred over the past 3300 years, the latest one possibly between 1485 cal BP and 1730 cal BP. 展开更多
关键词 eastern Kunlun fault Maqu fault Late Quaternary slip-rate offset terraces paleo-seismicity
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Thickness of calcium carbonate coats on stones of the Heishanxia terraces of the Yellow River and dating of coarse clastic sedimentary geomorphic surfaces 被引量:7
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作者 Chengqi Xing Gongming Yin +5 位作者 Guoyu Ding Yanchou Lu Xuhui Shen Qinjian Tian Zhizhang Chai Kaibo Wei 《Chinese Science Bulletin》 SCIE EI CAS 2002年第19期1594-1600,共7页
The calcium carbonate coats on stones developed in soil on the geomorphic surfaces of coarse clastic sediments in arid-semiarid regions contain evident information of age. The thickness of coats can be used not only a... The calcium carbonate coats on stones developed in soil on the geomorphic surfaces of coarse clastic sediments in arid-semiarid regions contain evident information of age. The thickness of coats can be used not only as a good age indicator for the geomorphic surfaces but also coats themselves can be directly used as dating materials in the ESR method. Through measuring the thickness of carbonate coats on stones in soils on the alluvial terraces in the mouth of the Heishanxia gorge of the Yellow River and ESR dating of layers separated from the carbonate coats, the average of accumulation rates of the thickness of carbonate coats on stones since 1.57 Ma was calculated to be 0.10 mm/ka in the studied area, and a regression equation between carbonate coat thickness and age was also generated. From these research results, ages of T2-T11 terraces of the Yellow River in the studied area were systematically determined, and their values are in turn 18 ka, 94 ka, 139 ka, 215 ka, 305 ka, 410 ka, 495 ka, 742 ka, 展开更多
关键词 DATING method of carbonate coats on STONES soil devel-opment Yellow River terraces geomorphic SURFACES Heishanxia gorge.
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极端暴雨条件下黄土区典型梯田防蚀效果研究 被引量:9
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作者 白先发 高建恩 +3 位作者 贾立志 张梦杰 马润年 张英英 《水土保持研究》 CSCD 北大核心 2015年第3期10-15,共6页
2013年黄土高原延安地区发生的极端暴雨导致水土保持工程损毁严重,因此急需研究不同类型梯田抗御暴雨侵蚀防蚀效果。选取安塞县同一地区典型梯田—大棚、梯田—大田和梯田—水窖—苹果3种具有不同水沙调控措施梯田,根据暴雨前后野外监... 2013年黄土高原延安地区发生的极端暴雨导致水土保持工程损毁严重,因此急需研究不同类型梯田抗御暴雨侵蚀防蚀效果。选取安塞县同一地区典型梯田—大棚、梯田—大田和梯田—水窖—苹果3种具有不同水沙调控措施梯田,根据暴雨前后野外监测资料,分析比较了3种梯田抗御暴雨侵蚀灾害的能力。结果表明:带有水沙调控措施的梯田防蚀效果明显好于无水沙调控措施的梯田。梯田—水窖—苹果侵蚀最轻,各阶梯田侵蚀等级均在中度侵蚀以下,平均土壤侵蚀模数仅为2 177t/km2;梯田—大棚由于在大棚基部修建有排水渠道其侵蚀程度次之,平均土壤侵蚀模数为18 269t/km2,但棚面集流效率高使得各阶梯田土壤侵蚀等级都在极强度侵蚀以上;梯田—大田侵蚀最严重,平均土壤侵蚀模数为23 921t/km2,由梯田顶部到底部土壤侵蚀逐渐加重,最下部3阶梯田累积侵蚀量占总侵蚀量的85.02%。黄土丘陵沟壑区发展高效农业需要在梯田上因地制宜修建水沙调控措施,以调节水沙时空分布,保障农业生产。 展开更多
关键词 水沙调控 土壤侵蚀 梯田 暴雨径流 黄土高原
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The Significance of Traditional Culture for Agricultural Biodiversity——Experiences from GIAHS 被引量:9
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作者 MA Nan YANG Lun +2 位作者 MIN Qingwen BAI Keyu LI Wenhua 《Journal of Resources and Ecology》 CSCD 2021年第4期453-461,共9页
Agricultural biodiversity has a high importance in social-cultural,economic,and environmental aspects,and can help in adapting to and withstanding climate change.Conserving the GIAHS sites and the important components... Agricultural biodiversity has a high importance in social-cultural,economic,and environmental aspects,and can help in adapting to and withstanding climate change.Conserving the GIAHS sites and the important components within them can help conserve the agricultural biodiversity and traditional agricultural culture of the whole country.This study considered Ifugao Rice Terraces,Dong’s Rice-Fish-Duck System,and Hani Rice Terraces System as three examples which show that traditional culture can be used to protect agricultural biodiversity,while as a carrier of traditional culture,agricultural biodiversity also conveys and protects the traditional culture of the nation.According to the analyses,through several years of efforts,the status of agricultural biodiversity and traditional culture in them has improved.Then,to further promote agricultural biodiversity conservation and traditional culture protection,several suggestions are made,such as establishing community seed banks;documenting and preserving traditional farming methods,techniques,and tools and developing participatory activities which encourage more farmers to participate in the protection work. 展开更多
关键词 agricultural biodiversity traditional culture Globally Important Agricultural Heritage Systems(GIAHS) rice terraces traditional variety
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Advantages and disadvantages of terracing:A comprehensive review 被引量:9
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作者 Chuxiong Deng Guangye Zhang +4 位作者 Yaojun Liu Xiaodong Nie Zhongwu Li Junyu Liu Damei Zhu 《International Soil and Water Conservation Research》 SCIE CSCD 2021年第3期344-359,共16页
For thousands of years,terracing has been one of the most important systems for preventing soil erosion,conserving water,and increasing agricultural production.Despite having a long history,the wide-ranging effects an... For thousands of years,terracing has been one of the most important systems for preventing soil erosion,conserving water,and increasing agricultural production.Despite having a long history,the wide-ranging effects and mechanisms of terracing are poorly understood owing to large-scale spatial and temporal distribution patterns and the challenges related to assessing the ecosystem services of terraced landscapes.Thus,our study aims to review comprehensively the effect of terraces by describing the mechanisms behind terraced systems.Terraces provide many ecosystem services,including the reduction of runoff and sediment by over 41.9%and 52%,respectively,and the improvement of grain yields and soil moisture content by 44.8%and 12.9%,respectively.In addition,terracing can also contribute toward the conservation of plant biodiversity on a local scale.However,as terraces age,a number of disadvantages gradually emerge,including interference with water circulation and the development of serious environmental problems caused by poorly designed or mismanaged terraces,where the average runoff and soil loss can be 1—5 times that of well-managed terraces.Although understanding the complexity and multifaceted effects of terracing is vital for terrace construction and management,the negative effects of terracing are often not considered,and existing studies have several shortcomings.Within this context,this paper aims to describe both the benefits and disadvantages of terracing,investigate the gaps in current research,as well as discuss preventive and remedial measures so as to negate the possible bad impacts of terracing. 展开更多
关键词 Ecosystem services terraces terrace abandonment terrace management Soil and water loss
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Drainage of paddy terraces impacts structures and soil properties in the globally important agricultural heritage of Hani Paddy Terraces,China
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作者 Ming Wang Li Rong +3 位作者 Yanbo Li Jiangcheng Huang Yuanmei Jiao Xiaoyan Wei 《International Soil and Water Conservation Research》 SCIE CSCD 2024年第1期64-76,共13页
Marginalization and abandonment of paddy terraces are widespread,but their effects on the sustainability of subsequent agricultural production are still unknown.Hani Paddy Terraces,included in Globally Important Agric... Marginalization and abandonment of paddy terraces are widespread,but their effects on the sustainability of subsequent agricultural production are still unknown.Hani Paddy Terraces,included in Globally Important Agriculture Heritage Systems,are threatened by paddy fields drainage.Here,changes in terrace structure,the productivity of topsoil(0-20 cm),and soil water holding capacity at 0-70 cm depth were determined in a case study of Hani Paddy Terraces in Amengkong River Basin in Yuanyang County in Southwestern China,which had been converted into dryland terraces for 2-14 years.Our results showed that:(1)The degree of terrace structures degradation exhibited a U-shaped curve with increasing time since draining,with those drained for 5-9 years having the best structure;(2)Soil productivity index decreased first and then increased with time after conversion;(3)Maximum water holding capacity at 0-70 cm soil depth dramatically decreased after conversion and such trend became increasingly obvious with increasing time since conversion.Our study revealed that drainage of paddy terraces along with associated changes in crop and field management led to an increase in soil productivity,but degradation of terrace structures and a decrease in water holding capacity will inhibit restoration to paddy terraces.These findings enhance the understanding of the biophysical changes due to marginalization in paddy terraces. 展开更多
关键词 Hani paddy terraces terraces marginalization terrace structure degradation Soil productivity Water holding capacity
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Climatic and tectonic controls on the fluvial morphology of the Northeastern Tibetan Plateau (China) 被引量:6
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作者 WANG Xianyan Jef VANDENBERGHE +1 位作者 LU Huayu Ronald VAN BALEN 《Journal of Geographical Sciences》 SCIE CSCD 2017年第11期1325-1340,共16页
The geomorphological evolution of the Northeastern Tibetan Plateau (NETP) could provide valuable information for reconstructing the tectonic movements of the region. And the considerable uplift and climatic changes ... The geomorphological evolution of the Northeastern Tibetan Plateau (NETP) could provide valuable information for reconstructing the tectonic movements of the region. And the considerable uplift and climatic changes at here, provide an opportunity for studying the im- pact of tectonic and monsoon climate on fluvial morphological development and sedimentary architecture of fluvial deposits. The development of peneplain-like surface and related land- scape transition from basin filling to incision indicate an intense uplift event with morphologi- cal significance at around 10-17 Ma in the NETP. After that, incision into the peneplain was not continuous but a staircase of terraces, developed as a result of climatic influences. In spite of the generally persisting uplift of the whole region, the neighbouring tectonic blocks had different uplift rates, leading to a complicated fluvial response with accumulation terraces alternating with erosion terraces at a small spatial and temporal scale. The change in fluvial activity as a response to climatic impact is reflected in the general sedimentary sequence on the terraces from high-energy (braided) channel deposits (at full glacial) to lower-energy de- posits of small channels (towards the end of the glacial), mostly separated by a rather sharp boundary from overlying flood-Ioams (at the glacial-interglacial transition) and overall soil formation (interglacial). Pronounced incision took place at the subsequent warm-cold transi- tions. In addition, it is hypothesized that in some strongly uplifted blocks energy thresholds could be crossed to allow terrace formation as a response to small climatic fluctuations (10^3-10^4 year timescale). Although studies of morpho-tectonic and geomorphological evolu- tion of the NETP, improve understanding on the impacts of tectonic motions and monsoonal climate on fluvial processes, a number of aspects, such as the distribution and correlation of peneplain and the related morphological features, the extent and in 展开更多
关键词 PENEPLAIN Miocene uplift fluvial terraces fluvial deposit climatic impact tectonic impact Northeastern Tibetan Plateau
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国产高分一号卫星数据傅里叶变换提取梯田影像可行性分析 被引量:8
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作者 赵欣 王晓晶 +4 位作者 赵院 罗志东 许永利 郭浩 张羿 《中国水土保持》 2016年第1期63-65,73,共3页
在研究国产高分一号卫星数据特点和梯田纹理特征的基础上,以国产高分一号卫星数据为数据源进行傅里叶变换提取梯田影像研究并进行了可行性分析。经过对包含不同地类、不同尺寸区域的提取测试发现,纹理特征不明显的梯田和纹理不均一的非... 在研究国产高分一号卫星数据特点和梯田纹理特征的基础上,以国产高分一号卫星数据为数据源进行傅里叶变换提取梯田影像研究并进行了可行性分析。经过对包含不同地类、不同尺寸区域的提取测试发现,纹理特征不明显的梯田和纹理不均一的非梯田易造成大量漏提和错提,综合分析认为傅里叶变换提取梯田影像算法难以满足工程化生产的需要。 展开更多
关键词 梯田 纹理特征 傅里叶变换 高分一号卫星 可行性
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黄土丘陵区不同种植类型梯田2m土层有机碳的分布特征 被引量:6
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作者 赵俊峰 肖礼 +2 位作者 黄懿梅 周俊英 刘洋 《水土保持学报》 CSCD 北大核心 2017年第5期253-259,共7页
为了明确黄土丘陵区梯田种植类型对0—200cm有机碳垂直分布的影响,以甘肃庄浪县堡子沟流域玉米、小麦、土豆、苹果和间作(苹果+土豆)5种典型种植类型梯田的土壤为研究对象,分析土壤有机碳含量、储量在0—200cm的垂直分布特征及影响因素... 为了明确黄土丘陵区梯田种植类型对0—200cm有机碳垂直分布的影响,以甘肃庄浪县堡子沟流域玉米、小麦、土豆、苹果和间作(苹果+土豆)5种典型种植类型梯田的土壤为研究对象,分析土壤有机碳含量、储量在0—200cm的垂直分布特征及影响因素,探讨种植类型对0—200cm土层有机碳分布稳定性的影响。结果表明:(1)5种种植类型梯田的0—200cm土层中,有机碳含量平均为3.33~4.86g/kg,储量平均为8.0~11.69t/hm^2;含量和储量均在间作和苹果地显著高于玉米地、小麦地(P<0.05);各样地有机碳含量均表现出明显的层次性,0—20cm显著高于其他各层(P<0.05),20cm以下的各层中的变异较小,有机碳储量的垂直分布特征与含量相同,且层次间差异更为显著。(2)土壤有机碳分配比例在0—20cm为17.57%,20—100cm为41.21%,100—200cm为41.22%,种植类型对0—200cm土层有机碳分布稳定性影响较小。有机碳分层比例SR(0—20cm/20—40cm)为1.51~1.78,SR(0—20cm/40—60cm)为1.78~2.02,表明土壤正向发育熟化,土壤质量明显提高。(3)水分能够影响有机碳垂直分布,种植类型对土壤有机碳的深层分布和固存有一定影响,苹果园的发展有利于梯田土壤有机碳的提高。 展开更多
关键词 黄土丘陵区 梯田 种植类型 土壤剖面 有机碳
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