Shan Yin

ICESat/GLAS-derived changes in the water level of Hulun Lake, Inner Mongolia, from 2003 to 2009

Hulun Lake is the largest freshwater lake in northern Inner Mongolia and even minor changes in its level may have major effects on the ecology of the lake and the surrounding area. In this study, we used high-precision elevation data for the interval from 2003–2009 measured by the Geoscience Laser Altimetry System (GLAS) on board the Ice, Cloud, and land Elevation Satellite (ICESat) to assess annual and seasonal water level variations of Hulun Lake. The altimetry data of 32 satellite tracks were processed using the RANdom SAmple Consensus algorithm (RANSAC) to eliminate elevation outliers, and subsequently the Normalized Difference Water Index (NDWI) was used to delineate the area of the lake. From 2003–2009, the shoreline of Hulun Lake retreated westwards, which was especially notable in the southern part of the lake. There was only a small decrease in water level, from 530.72 m to 529.22 m during 2003–2009, an average rate of 0.08 m/yr. The area of the lake decreased at a rate of 49.52 km2/yr, which was mainly the result of the shallow bathymetry in the southern part of the basin. The decrease in area was initially rapid, then much slower, and finally rapid again. Generally, the lake extent and water level decreased due to higher temperatures, intense evaporation, low precipitation, and decreasing runoff. And their fluctuations were caused by a decrease in intraannual temperature, evaporation, and a slight increase in precipitation. Overall, a combination of factors related to climate change were responsible for the variations of the water level of Hulun Lake during the study interval. The results improve our understanding of the impact of climate change on Hulun Lake and may facilitate the formulation of response strategies.

Drought hazard assessment and possible adaptation options for typical steppe grassland in Xilingol League, Inner Mongolia, China

Droughts cause both major financial losses to society as well as environmental damage, especially in arid and semi-arid regions, where the economy relies upon rainfed pastoralism and cultivation. Droughts are becoming increasingly frequent and intense with ongoing global climate change. Moving from a reactive to a preventative mode of drought response is the key to minimizing drought-related economic and environmental costs, and drought hazard analysis is becoming increasingly important. Xilingol League, in Inner Mongolia, consists of typical steppe and is seriously affected by drought. In this study, we conducted a drought hazard analysis based on two drought indices, the precipitation anomaly percentage (Pa) and the standardized precipitation evapotranspiration index (SPEI), using data from a series of meteorological monitoring stations from across the region. The drought hazard values were used to define zones which were divided into five levels using a natural break-point. Of the two indexes, Pa was found to be the more effective and the corresponding drought hazard map resembles the spatial distribution of precipitation, decreasing from northwest to southeast. Improving awareness of livestock farmers to drought risk is important for disaster mitigation and we propose that drought hazard-based insurance can play an important role. Finally, we propose a series of drought adaptation measures to reduce the possibility and intensity of drought, both in theory and in practice. Our results potentially provide improved insights into the drought hazard and may be helpful in developing appropriate adaptation and mitigation strategies to cope with the adverse effects of drought.

Scenario-based hazard analysis of extreme high-temperatures experienced between 1959 and 2014 in Hulunbuir, China

Purpose Extreme high temperatures are a significant feature of global climate change and have become more frequent and intense in recent years. These pose a significant threat to both human health and economic activity, and thus are receiving increasing research attention. Understanding the hazards posed by extreme high temperatures are important for selecting intervention measures targeted at reducing socioeconomic and environmental damage. Design/methodology/approach In this study, detrended fluctuation analysis is used to identify extreme high-temperature events, based on homogenized daily minimum and maximum temperatures from nine meteorological stations in a major grassland region, Hulunbuir, China, over the past 56 years. Findings Compared with the commonly used functions, Weibull distribution has been selected to simulate extreme high-temperature scenarios. It has been found that there was an increasing trend of extreme high temperature, and in addition, the probability of its indices increased significantly, with regional differences. The extreme high temperatures in four return periods exhibited an extreme low hazard in the central region of Hulunbuir, and increased from the center to the periphery. With the increased length of the return period, the area of high hazard and extreme high hazard increased. Topography and anomalous atmospheric circulation patterns may be the main factors influencing the occurrence of extreme high temperatures. Originality/value These results may contribute to a better insight in the hazard of extreme high temperatures, and facilitate the development of appropriate adaptation and mitigation strategies to cope with the adverse effects.

Evaluation of Eco-environmental Sensitivity in Xilingol Grassland

This paper selected the soil erosion, land desertization, bio-inhabitation as sensitive factor to research eco-environmental sensitivity spatial distribution characteristics of the Xilingol Grassland. (1)slight sensitivity is the main level of soil erosion sensitivity, which mainly distributes in the flat terrain of the plain area. Moderately sensitive area is distributed in mountainous and hilly areas.(2)In-sensitive and slight sensitive areas of desertification accounted for 0.004% and 3.186% of the total area, respectively, and the proportion of moderately sensitive area was 46.533%, and highly sensitive area mainly distributed in the Hunshandake sandy land, where vegetation relatively sparse, and sand is the main soil type, and the sandstorm weather often happened. Sonid right and Sonid left banner is extreme sensitive area.(3)Bio-inhabitation sensitive level has a downward trend from southeast to northwest, highly sensitive areas distributed in the mountainous areas with high vegetation coverage and abundant rainfall. (4)Eco-environmental sensitive index is between 1.50935-5.57577 in Xilingol grassland, where the main sensitivity type is slight sensitivity, *通讯作者:银山,yinshan@imnu.edu.cn. moderately sensitive areas distributed in Sonid right banner, Sonid left banner, Boarder Yellow banner, Abagaqi, west ujimqin and Xilinhot.

The Relationship between Teachers and Students from the Perspective of Geography

On the geography teachers and students from the perspective of relationship were studied, the previous studies on the relationship between teachers and students lack of empirical and practical. This paper adopts empirical research method of questionnaire investigation and literature collection, research status of the relationship between teachers and students from the perspective of the current geography learning level students from different angle, and the establishment of different levels of study of teacher-student relationship provides useful suggestions. Keywords—Geographical perspective, the relationship between teachers and students, Teacher, Middle school student, College student, Graduate student