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CHARACTERISTICS OF THE INTERANNUAL AND INTERDECADAL TIMESCALES OF EVAPORATION IN NORTHERN china IN THE RECENT 115.YEARS

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Journal of Hydrodynamics 2006年第5期18卷 593-596页

作者： RONG Yan-shu TU Qi-pu DUAN Li-yao College of Water resources and Environment Hohai University Nanjing 210098 China Tianjin Institute of Meteorological Science Tianjin 300074 China Tianjin Institute of Meteorological Science Tianjin 300074 China Nanjing University of information Science and Technology Nanjing 210044 China Tianjin Climate Centre Tianjin 300074 China

Evaporation plays an important role in water balance on the land surface. In Northern china, the evaporation series of the recent 11{2.years was reconstructed on the basis of Yhornthwaite evaporation formula. The characteristics of the reconstructed series were analyzed using 10-year running mean filter, power spectrum method, and running t-text of abrupt changes on the paper. The results showed that there were remarkable interannual fluctuations with timescales of about quasi-8-year, 3-4-year, and quasi-2.year, and interdecadal oscillations with timescales of {2..{2.year, quasi-2.-year, and l l.{2.year. Meanwhile, the abrupt changes of the evaporation series were also of interdecadal timescale. Either interannual fluctuations or interdecadal oscillations of evaporation were closely related to variations in air temperatures and precipitation.

关键词： reconstructed evaporation series interannual timescale interdecadal timescale Northern china

Soil Fertility Indices of Citrus Orchard land Along Topographic Gradients in the Three Gorges Area of china

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Pedosphere 2011年第6期21卷 782-792页

作者： WU Dian-Ming YU Yuan-Chun XIA Li-Zhong YIN Shi-Xue YANG Lin-Zhang College of Forest resources and Environment Nanjing Forestry University Nanjing 210037 （China） State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） College of Environmental Science and Engineering Yangzhou University Yangzhou 22500g （China）

In the Three Gorges Area of china, soil erosion and the resultant non-point source pollution and ecological degradation have endangered agricultural ecosystems and fresh water reservoirs. Although efforts have been undertaken to reduce soil and water losses from slope land used for citrus production, {2. on the effects of management practices on soil fertility indices is either limited or nonexistent. This study was conducted to compare the effects of 10 years of various management practices, citrus intercropped with white clover (WC), citrus mulched with straw (SM), citrus intercropped with contour hedgerows (CH), citrus orchard land with impermeable membrane (IM), and citrus intercropped with wheat (Triticum aestivum) and peanut (Arachris hypogaea) (WP), as treatments on soil fertility indices with that of the conventional citrus management (CM). Results showed that the soil organic carbon, total and available nitrogen, available potassium, and water-stable aggregate (> 0.2.4}mm) contents at the 0–5.cm depth were higher for the WC and SM treatments than the CM treatment. There was also spatial variation in soil fertility along slopes of the WC and SM treatments. The soil total and available nitrogen, phosphorus, and potassium, and water-stable aggregate (> 0.2.4}mm) contents at both the 0–5.and 5.2. cm depths were higher for the CH and IM treatments than the CM treatment. The average soil available nitrogen and available potassium contents were higher for the WP treatment than the CM treatment, but the WP treatment had little effect on the soil organic carbon, total nitrogen, and water-stable aggregate (> 0.2.4}mm) contents. These suggested that white clover intercropping and straw mulching were the most effective approaches to improve soil fertility in citrus orchard land of the Three Gorges area.

关键词： intercropping slope land soil nutrients soil water-stable aggregates straw mulching

Spatial-Temporal Changes in Grain Production, Consumption and Driving Mechanism in china

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Journal of Integrative Agriculture 2013年第2期12卷 374-385页

作者： XU Shi-wei WU Jian-zhai SONG Wei LI Zhi-qiang LI Zhe-min KONG Fan-tao Key Laboratory of Digital Agricultural Early-Warning Technology Ministry of Agriculture/Agriculture Information Institute Chinese Academy of Agriculture Sciences Institute of Geographic Sciences and Natural resources Research Chinese Academy of Sciences

The spatial-temporal patterns of grain production and consumption have an important influence on the effective national grain supply on condition of tight balance in the total grain amount in china. In this paper, we analyze the spatial-temporal pattems of grain production, consumption and the driving mechanism for their evolution processes in china. The results indicate that both gravity {2.s of grain production and consumption in china moved toward the northern and eastern regions, almost in the same direction. The coordination of grain production and consumption increased slightly from 1995.to 2.07 but decreased from 2.00 to 2.07. There is a spatial difference between the major districts of output increase and the strong growth potential in grain consumption, which indicates an increasing difficulty in improving the regional coordination of grain production and consumption. The movement of the gravity {2. of grain production is significantly correlated with regional differences in grain production policy, different economic development models, and spatial disparity of {5. and water resource use. For grain consumption, the main driving factors include rapid urbanization, the upgrade of food consumption structure, and distribution of food industries.

关键词： grain production grain consumption gravity center driving mechanism

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西藏台错晚第四纪轮藻类的新类型

微体古生物学报 2011年第2期28卷 145-168页

作者：刘俊英王海雷国土资源部盐湖资源与环境重点实验室北京100037 中国地质科学院盐湖与热水资源研究中心北京100037 中国地质科学院地质研究所北京100037 中国地质科学院矿产资源研究所北京100037

本文的研究材料来自西藏羌塘高原西部台错古湖一个3.69 m的天然剖面,其地层测年为32.6—4.5.a。从其15.个样品中获取大量的轮藻类、介形类和腹足类及少量有孔虫等微体化石。据轮藻类藏卵器外形,顶部结构、螺旋细胞钙化式样等特征,该剖... 详细信息

本文的研究材料来自西藏羌塘高原西部台错古湖一个3.69 m的天然剖面,其地层测年为32.6—4.5.a。从其15.个样品中获取大量的轮藻类、介形类和腹足类及少量有孔虫等微体化石。据轮藻类藏卵器外形,顶部结构、螺旋细胞钙化式样等特征,该剖面的轮藻类应归属于轮藻科Characeae之轮藻属Chara。经研究得知,台错古湖在大约2. ka的时期内,曾生长过2.种轮藻,其中新类型7个,包括新种4个:Chara platea,***,***和***;新型2.:***,***;新变种1个:***。其余是曾产于国内外第四系的Chara其它分子。其中有5.新联合种:Chara alba(Madler et Staesche),***(Tang et Di),***(Tang et Di),***(Tang etDi)和***。该剖面轮藻类、介形类、腹足类等多门类微体化石的紧密共生,对轮藻植物群生态学研究具重要意义。

关键词：轮藻类新类型晚第四纪台错西藏

基于粗糙集理论的工矿废弃地复垦利用实施效果评价模型及应用

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中国矿业 2016年第S1期25卷 249-254页

作者：张立平叶回春周妍兴安黄元仿张红艳中国农业大学资源与环境学院北京100193 农业部华北耕地保育重点实验室北京100193 国土资源部农用地质量与监控重点实验室北京100035 中国科学院遥感与数字地球研究所数字地球重点实验室北京100094 海南省地球观测重点实验室海南三亚572029 国土资源部土地整治中心北京100035 中国农业大学理学院北京100193

工矿废弃地复垦利用实施效果评价对于量化各试点省份工作效果以及加强工矿废弃地复垦监管具有重要意义。本文构建了工矿废弃地复垦利用实施效果评价指标体系,并利用粗糙集理论知识约简和相对正域理论在消除冗余信息和处理不确定性信息... 详细信息

工矿废弃地复垦利用实施效果评价对于量化各试点省份工作效果以及加强工矿废弃地复垦监管具有重要意义。本文构建了工矿废弃地复垦利用实施效果评价指标体系,并利用粗糙集理论知识约简和相对正域理论在消除冗余信息和处理不确定性信息等方面的优势,从而进一步确定了评价指标体系中各准则层的权重。结果表明:以湖北、江苏等12.省份的工矿废弃地复垦利用试点效果评价为例,对上述赋权思路进行实例分析,对比传统特尔斐法和粗糙集理论赋权结果发现,特尔斐法确定的专项规划审批(C_1)、复垦项目实施进展(C_2.、建新审批(C_3)、制度建设(C_4)、技术规范制定与实行(C_5.和信息化管理(C_6)的6个准则层指标权重分别为0.180、0.360、0.060、0.2.0、0.090和0.100,而粗糙集理论确定的C_1-C_6这6个准则层指标权重分别为0.143、0.190、0.095.0.190、0.191和0.191,其中,C_1、C_2.C_4权重下降,C_3、C_5.C_5.重上升。因而,粗糙集理论在工矿废弃地复垦利用实施效果评价中的具体赋权思路基本是可行的,可为工矿废弃地相关领域的评价提供参考和借鉴。

关键词：工矿废弃地复垦利用实施效果评价粗糙集理论权重确定

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西藏帕里湖卫星遥感监测

山地学报 2009年第2期27卷 240-247页

作者：王治华徐起德中国国土资源航空物探遥感中心

为查明2.04年和2.05.夏季在中印边界附近发生的滑坡堰塞湖溃坝灾害,采用高分辨率为主的多时相卫星图像和'数字滑坡'技术对帕里河中段从形成堰塞湖到溃坝的整个过程进行了监测。监测结果表明位于喜马拉雅山脉西段的帕里湖为高原山地萎... 详细信息

为查明2.04年和2.05.夏季在中印边界附近发生的滑坡堰塞湖溃坝灾害,采用高分辨率为主的多时相卫星图像和'数字滑坡'技术对帕里河中段从形成堰塞湖到溃坝的整个过程进行了监测。监测结果表明位于喜马拉雅山脉西段的帕里湖为高原山地萎缩湖盆,滑坡筑坝形成堰塞湖至溃坝可分为4个阶段,估算溃坝前湖面的最大高程、最大面积和最大水量分别达3907m、1.75.m2.6144×104m3,2.05.06-2.溃坝的下泄洪水量为3738×104m3。预测未来汛期帕里湖下游仍然存在崩塌滑坡活动及短暂堵江形成堰塞湖的可能性,但其规模将大多小于2.04～2.05.的灾害。在本次遥感监测的基础上,定期进行遥感监测,当帕里湖水面面积≥1.6km2.,即通知下游作好撤离等避灾准备,是目前最经济有效的预警防灾措施。

关键词：帕里湖卫星遥感监测数字滑坡技术堰塞湖溃坝灾害

基于GIS的流域土壤侵蚀量估算指标模型方法——以嘉陵江上游西汉水流域为例

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水土保持学报 2001年第2期15卷 105-107,116页

作者：黄诗峰钟邵南徐美水利部遥感技术应用中心北京100044 中国水利水电科学研究院北京100044

在分析土壤侵蚀形成的各主要影响因子的基础上 ,提出了基于栅格地理信息系统的流域土壤侵蚀量估算的指标模型。结合嘉陵江上游西汉水流域具体情况 ,以降雨、地形、沟谷密度、植被盖度、成土母质等为主要指标 ,对流域土壤侵蚀量进行了估... 详细信息

在分析土壤侵蚀形成的各主要影响因子的基础上 ,提出了基于栅格地理信息系统的流域土壤侵蚀量估算的指标模型。结合嘉陵江上游西汉水流域具体情况 ,以降雨、地形、沟谷密度、植被盖度、成土母质等为主要指标 ,对流域土壤侵蚀量进行了估算。

关键词：地理信息系统土壤侵蚀土壤侵蚀量估算指标模型嘉陵江上游西汉水流域

Comparisons of speckle noise filtering methods on high resolution SAR image

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Comparisons of speckle noise filtering methods on high resol...

青海湖裸鲤繁殖群体遗传多样性的RAPD分析

2.10 International Conference on Computer and Communication Technologies in Agriculture Engineering (CCTAE 2.10)

作者： Wei Zhang and Jinzhong Yang china Aero Geophysical Survey & Remote Sensing center for {2. and resources Beijing 100083 china Le Yu Department of Earth Sciences Zhejiang University Hangzhou 31002. china

Numerous image processing methods to suppress the speckle noise in synthetic aperture radar （SAR） have been *** is always a tradeoff between smoothing out speckle and preserving the useful spatial information （***,texture）.This paper proposed a novel index by integrating the evaluation of both speckle and edge preservation to evaluate the balance of the aforementioned two *** of the well-known adaptive speckle suppression filters are then compared and evaluated using two high resolution SAR datasets on heterogeneous *** result shows that Kuan filter performance better in preserving image sharpness and detail while suppressing noise.

关键词： speckle noise suppression adaptive filter Radarset-2 COSMO-SkyMed

来源： cnki会议评论

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水产学报 2005年第3期29卷 307-312页

作者：张春霖陈大庆史建全祁洪芳鲁成西南农业大学水产学院中国科学院水生生物研究所淡水生态与生物技术国家重点实验室青海省鱼类原种良种场青海省鱼类原种良种场西南农业大学农业部蚕桑学重点实验室重庆北碚400716 中国水产科学研究院长江水产研究所农业部淡水鱼类种质资源与生物技术重点开放实验室湖北荆州434000湖北武汉430072 中国水产科学研究院淡水渔业研究中心江苏无锡214081青海西宁810016青海西宁810016重庆北碚400716

采用随机扩增多态性DNA(RAPD)方法对青海湖裸鲤的3个洄游繁殖群体-黑马河(HM)、布哈河(BH)及沙柳河(SL)群体各30个个体的DNA多态性进行了分析。用13个引物在三个群体中共检测出85.位点,其中多态性位点68个。青海湖裸鲤群体总的DNA多态... 详细信息

采用随机扩增多态性DNA(RAPD)方法对青海湖裸鲤的3个洄游繁殖群体-黑马河(HM)、布哈河(BH)及沙柳河(SL)群体各30个个体的DNA多态性进行了分析。用13个引物在三个群体中共检测出85.位点,其中多态性位点68个。青海湖裸鲤群体总的DNA多态位点百分率为80.0%。数据分析结果显示:青海湖裸鲤3个群体总的Nei基因多样性为0.3395.Shannon遗传多样性信息指数为0.4861,存在着较为丰富的遗传多样性。青海湖裸鲤3个群体间平均遗传距离为0.0788,基因分化系数Gst为0.1070,表明3个繁殖群体间产生了一定程度的遗传分化,通过UPGMA方法进行聚类分析显示,HM群体和BH群体优先聚类,表示它们之间的基因交流程度要高于它们分别与SL群体之间的交流。

关键词：青海湖裸鲤 DNA多态性遗传多样性遗传分化基因交流