Spatial characteristics of the stability of mangrove ecosystems in freshwater and seawater floods in Southeast Asia     

Li  Xia  Liu  Zhenhai  Wang  Shaoqiang  Li  Fengting  Li  Hui  Zhu  Tongtong  Qian  Zhaohui  Tu  Yongkai  Liu  Yuanyuan  Wang  Xiaobo  Wang  Qinyi  Shi  Weibo  Li  Donghui 《地理学报(英文版)》2022,32(9):1831-1846

Journal of Geographical Sciences - In tropical regions, mangrove forests are located in the inter-tidal areas between land and sea, and are at risk from both freshwater and seawater floods. Using...  相似文献   

数码调绘系统在1∶10000数字化图生产中的应用     

夏先丽  邱学智  苏东辉 《测绘标准化》2011,(2):47-48

针对野外测量生产数字化的薄弱环节研发的数码调绘系统,提高了野外调绘的工作效率,解决了新增地物标绘的精度问题,为数字化图生产与建库的前端数据采集提供了新方法。主要介绍数码调绘系统在基础测绘1∶10000数字线划图生产中的应用,通过对数码调绘系统定位精度的检测,进一步阐述其优势及实际应用中应注意的问题。  相似文献   

Coupling a glacier melt model to the Variable Infiltration Capacity (VIC) model for hydrological modeling in north-western China   总被引：3，自引：0，他引：3  

Qiudong Zhao  Baisheng Ye  Yongjian Ding  Shiqiang Zhang  Shuhua Yi  Jian Wang  Donghui Shangguan  Chuancheng Zhao  Haidong Han 《Environmental Earth Sciences》2013,68(1):87-101

For the sustainable utilization of rivers in the mid and downstream regions, it is essential that land surface hydrological processes are quantified in high cold mountains regions, as it is in these regions where most of the larger rivers in China acquire their headstreams. Glaciers are one of the most important water resources of north-west China. However, they are seldom explicitly considered within hydrological models, and climate-change effects on glaciers, permafrost and snow cover will have increasingly important consequences for runoff. In this study, an energy-balance ice-melt model was integrated within the Variable Infiltration Capacity (VIC) macroscale hydrological model. The extended VIC model was applied to simulate the hydrological processes in the Aksu River basin, a large mountainous and glaciered catchment in north-west China. The runoff components and their response to climate change were analyzed based on the simulated and observed data. The model showed an acceptable performance, and achieved an efficiency coefficient R ² ≈ 0.8 for the complete simulation period. The results indicate that a large proportion of the catchment runoff is derived from ice meltwater and snowmelt water. In addition, over the last 38 years, rising temperature caused an extension in the snow/ice melting period and a reduction in the seasonality signal of runoff. Due to teh increased precipitation runoff, the Aksu catchment annual runoff had a positive trend, increasing by about 40.00 × 10⁶ m³ per year, or 25.7 %.  相似文献   

四川南部城市群主要环境工程地质问题     

王东辉  陈绪钰  田凯 《城市地质》2013,(4):35-39

四川南部城市群为成渝经济区区域规划中四大城市群之一,有望成为四川省第二大增长极。区内多为丘陵山地型城市,有限的发展空间迫使城市建设活动中频繁的削坡、回填,在获得发展空间的同时也引发了大量的环境工程地质问题。地震活动、红层风化,地质灾害是区内最主要的环境工程地质问题。通过分析前人研究成果结合收集资料分析得出：华（？）山断裂及荥经-马边-盐津断裂在区内均表现为强活动性,地震活动频繁。侏罗系-白垩系红层泥岩具有快速风化的特性,红层边坡具有剥落、崩塌、落石、表层溜塌、滑塌、浅层滑坡六大破坏方式。区内地质灾害频发,发育密度达7.81处/100km~2,地质灾害类型以滑坡、崩塌为主。  相似文献   

Hydromedusae from the Arctic in 2010 during the 4th Chinese National Arctic Research Expedition (CHINARE 4)     

WANG Chunguang  HUANG Jiaqi  XIANG Peng  WANG Yanguo  XU Zhenzu  GUO Donghui  LIN Mao 《海洋学报(英文版)》2014,33(6):95-102

Fifty-seven stations(48 grid stations and nine stratified stations) were sampled across the study region(67.000°–88.394°N, 152.500°–178.643°W) during the 4th Chinese National Arctic Research Expedition(CHINARE 4) from July to August 2010 by the icebreaker R/V Xuelong. A total of 24 species of Hydromedusae were identified from 130 zooplankton samples, of which seven species belonged to Automedusa, eight species to Anthomedusae, four species to Leptomedudae, and three species to Siphonophora. Catablema multicirratum Kishinouye, 1910, Bougainvillia bitentaculata Uchida, 1925, and Euphysa japonica(Maas, 1909) were recorded for the first time in the Arctic sea. In the present paper, 18 species of Hydromedusae were described and illustrated, of which three species were described for the first time in the Arctic sea, and 15 species were described for the first time in China.  相似文献   

Diagnostic model construction and example analysis of habitat degradation in enclosed bay: I. diagnostic model construction     

于格  孙芃  刘光兴  徐东晖  丁光茂  黄东仁 《中国海洋湖沼学报》2014,32(3):626-635

Presently, research is lacking regarding the diagnosis and evaluation of habitat degradation in enclosed bay systems. We established a diagnostic model for enclosed bay habitat degradation （EBHD model） using a multi-approach integrated diagnostic method in consideration of driving force-pressure- state-influence-response. The model optimizes the indicator standardization with annual average change rate of habitat degradation as the basic element, to reflect accurately the impact of the change and speed of degradation on the diagnostic results, to quantify reasonably the contribution of individual diagnostic indicator to habitat degradation, and to solve the issue regarding the influence of subjective factors on the evaluation results during indicator scoring. We then applied the EBHD model for the Sansha Bay in Fujian Province, China, evaluated comprehensively the situation of habitat degradation in the bay, and screened out the major controlling factors in the study area. Results show that the diagnostic results are consistent in overall with the real situation of the study area. Therefore, the EBHD model is advantageous in terms of objectivity and accuracy, making a breakthrough in diagnosis and evaluation for habitat degradation in enclosed bay systems.  相似文献   

Diagnostic model construction and example analysis of habitat degradation in enclosed bay: II. spatiotemporal variations in habitat degradation in Sansha Bay   总被引：1，自引：0，他引：1  

于格  孙芃  刘光兴  徐东晖  丁光茂  黄东仁 《中国海洋湖沼学报》2014,32(3):636-644

The process of habitat degradation varies in habitat type and driving force which shows certain spatial and temporal heterogeneity on regional scales. In the present study, a new diagnostic model for enclosed bay habitat degradation was established, with which the spatial and temporal variation patterns of habitat degradation during 1991–2012 in Sansha Bay, Fujian, China was investigated. The results show that anthropogenic disturbance is the major controlling factor for the habitat degradation in large temporal heterogeneity in the bay. On the other hand, the habitat degradation experienced signifi cant spatial variations among six sub-bays. Under the joint action of temporal and spatial heterogeneity, the degradation trend in growing scale shows a more signifi cant correlation with the distribution of local leading industries along shorelines. Therefore, we quantifi ed the main characters of habitat degradation in Sansha Bay, and have understood the relationship between the status of habitats spatio-temporal variation value and the main controlling factor leading to the changes. However, a defi ciency of this research is the lack of or inaccessible to the detailed data, which shall be better solved in the future study for accessing more data from more sources.  相似文献   

极地区域气溶胶地基遥感观测及分析   总被引：1，自引：0，他引：1  

李东辉  李正强  卞良  李凯涛  李保生  顾行发  PODVIN Thierry 《遥感学报》2013,17(3):553-565

依据全球气溶胶自动观测网在极地区域的观测,对以下问题进行了讨论:(1)温度订正在极地气溶胶光学厚度观测中的重要性及订正方法;(2)在极地进行仪器常数标定的可行性分析及温度效应的影响;(3)利用天空散射光观测反演气溶胶微物理和光学特性参数(粒子谱分布、散射相函数、复折射指数、单次散射反照率等)时,关于观测几何选择的问题,以及针对极地区域气溶胶特性的初步反演结果。这些研究可以为中国未来在两极地区开展基于自动太阳-天空辐射计的气溶胶地基遥感观测提供参考,为极地区域气溶胶卫星遥感及气候效应评估等研究提供重要支撑。  相似文献   

Pinpointing source of Mekong and measuring its length through analysis of satellite imagery and field investigations     

Shaochuang Liu  Pingli Lu  Donghui Liu  Peidong Jin 《地球空间信息科学学报》2013,16(1):51-56

For centuries, explorers and scientists from different countries had made their own conclusions on the source of the Mekong. However, the geographic source of the Mekong is still arguable because of the complexity of the Mekong source water system, inaccessible environment and the varied technologies used by those explorers and scientists. The satellite remote sensing technology has been used to pinpoint the source of the Mekong, associated with the on-the-spot investigations made by the authors in June 1999 and September 2002. The actual length of the Mekong has also been calculated.  相似文献   

A hydrographic method to identify the groundwater net recharge,barometric effect and evapotranspiration from a complicated semidiurnal water table fluctuation     

Donghui Cheng  Jing Yuan  Lijun Qi 《水文研究》2021,35(10):e14383

A hydrographic method was proposed to separate out the hourly scaled groundwater level changes caused by net recharge, barometric effects and evapotranspiration from a semidiurnal water table fluctuation. A characteristic midnight time, with a turning point of the barometric pressure change and high relative air humidity, which meant that neither the barometric effect nor groundwater evapotranspiration occurred, was proposed for determining the net recharge rate r_net. Then, the barometric efficiency f_bar was estimated using the other time period without evapotranspiration, and the evapotranspiration rate r_ETG was finally obtained using the remainder of the water level changes. A case example illustrated that estimation of f_bar using the proposed method was more accurate than that using the traditional error analysis method, which may result in a significant underestimation under the condition of the present water level changes. Additionally, the abnormal semidiurnal fluctuations, more specifically, two step-down fluctuations, which may be a common pattern when the groundwater level is controlled by net recharge, barometric effects and evapotranspiration, can be well understood using the three components separated out. The results also showed that nighttime groundwater evapotranspiration, accounting for an average of 23% of that during the daytime, cannot be ignored.  相似文献