Han Li

Ms. Han Li

orcid

Research Focus & Metrics

Academic Career Length

19Years (2008-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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HLHan Li
Han Li
Wei SongWei Song
Wei Song
As the “Third Pole”, the Qinghai-Tibet Plateau is threatened by environmental changes. Ecosystem vulnerability refers to the sensitivity and resilience of ecosystems to external disturbances. However, there is a lack of relevant studies on the driving factors of ecosystem vulnerability. Therefore, based on spatial principal components analysis and geographic detectors methods, this paper evaluates the ecosystem vulnerability and its driving factors on the Qinghai-Tibet Plateau from the years 2005 to 2015. The results were as follows: (1) The ecosystem vulnerability index (EVI) of the Qinghai-Tibet Plateau is mainly heavy and extreme, showing a gradually increasing trend from southeast to northwest. (2) The spatial heterogeneity of the EVI is significant in the southeast and northwest, but not in the southwest and central parts. (3) Analysis of influencing factors shows that environmental factors have more significant effects on EVI than socioeconomic variables, facilitating the proposal of adequate policy implications. More efforts should be devoted to ecological protection and restoration to prevent grassland degradation and desertification in the high-EVI areas in northwest. The government is also urged to improve the ecological compensation mechanisms and balance ecological protection and residents’ development needs in the southeast.

LLLin Liu
Lin Liu
Wei SongWei Song
Wei Song
YZyanjie zhang
yanjie zhang
ZHZe Han
Ze Han
HLHan Li
Han Li
QHQiang Huang
Qiang Huang
Ecosystem restoration has been widely concerned with the damage and degradation of ecosystems worldwide. Scientific and reasonable formulations of ecological restoration zoning is the basis for the formulation of an ecological restoration plan. In this study, a restoration zoning index system was proposed to comprehensively consider the ecological problems of ecosystems. The linear weighted function method was used to construct the ecological restoration index (ERI) as an important index of zoning. The research showed that: (1) the ecological restoration zones of the Qilian Mountains can be divided into eight basins, namely the headwaters of the Datong River Basin, the Danghe-Dahaerteng River Basin, the northern confluence area of the Qinghai Lake, the upper Shule River to middle Heihe River, the Oasis Agricultural Area in the northern foothills of the Qilian Mountain, the Huangshui Basin Valley, Aksay (corridor region of the western Hexi Basin), and the northeastern Tsaidam Basin; (2) the restoration index of the eight ecological restoration zones of the Qilian Mountains was between 0.34–0.8, with an average of 0.61 (the smaller the index, the more prominent the comprehensive ecological problem representing the regional mountains, rivers, forests, cultivated lands, lakes, and grasslands, and thus the greater the need to implement comprehensive ecological protection and restoration projects); and (3) the ecological problems of different ecological zones are frequently numerous, and often show the phenomenon of multiple overlapping ecological problems in the same zone.

7 November 2021 in Land
Verified
Journal Article
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HLHan Li
Han Li
Wei SongWei Song
Wei Song
Cropland abandonment occurs frequently in many countries and regions around the world, particularly in those with poor environmental conditions, such as mountainous regions. In Chongqing county, China, over 76% of the total area is mountainous. Due to the lack of reliable remote sensing monitoring and identification methods, the spatial and temporal distribution of abandoned cropland areas and its underlying causes are poorly understood. Thus, the extent of cropland abandonment in Chongqing, since 2001, was estimated using land use trajectories. The following results were obtained: (1) the cropland abandonment rate was 12.2–15.4% from 2001 to 2020, with an average of 13.3%; (2) hotspots of abandoned cropland were concentrated in the north and southeast. Cropland abandonment was clustered in the northern, southeastern, and southwestern areas; (3) socio-economic factors (including gross domestic product density, population density, and road density) had a greater impact on the spatial distribution of abandoned cropland than environmental factors. Based on the results, the government should strive to reduce production costs associated with poor agricultural infrastructure, sporadic cropland, and higher labor costs by providing grain subsidies, undertaking cropland consolidation, encouraging land transfer, and improving agricultural infrastructure.

10 October 2020 in Climate
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Journal Article
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HLHan Li
Han Li
Wei SongWei Song
Wei Song
The Lancang-Mekong River is an important international river in Southeastern Asia. In recent years, due to climate change, natural disasters, such as drought and flooding, have frequently occurred in the region, which has a negative effect on the sustainable development of the social economy. Due to the lack of meteorological monitoring data in the six countries across the region, the study of the characteristics of climate change in this area is still scarce. In this paper, we analyze the characteristics of climate change in the Lancang-Mekong sub-region (LMSR) during 2020–2100 based on the climatic data of CMIP5, using the linear trend rate method, cumulative anomaly method, the Mann–Kendall test, and Morlet wavelet analysis. The results showed that the annual mean temperature and annual precipitation in the LMSR increased significantly. The annual average temperature in this area increased at a rate of 0.219 °C/10a (p < 0.05) and 0.578 °C/10a (p < 0.05) in the RCP4.5 and RCP8.5 scenarios, respectively; the annual precipitation in the area was 29.474 mm/10a (p < 0.05) and 50.733 mm/10a (p < 0.05), respectively. The annual average temperature in the region changed abruptly from low to high temperatures in 2059 for the RCP4.5 scenario and 2063 for RCP8.5. The annual precipitation in the area changed from less to more in 2051 for the RCP4.5 scenario and 2057 for RCP8.5. The results of wavelet analysis showed that the annual mean temperature in the LMSR had no significant change period at the 95% confidence level under the scenario of RCP4.5 and RCP8.5. Under the scenario of RCP4.5 and RCP8.5, the annual precipitation had a significant 3.5-year and 2.5-year periodicity, respectively. Extreme climate events tended to increase against the background of global warming, especially in high emission scenarios.

15 October 2008 in Chromatographia
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HLHan Li
Han Li
BGBaoyuan Guo
Baoyuan Guo
JFJunhe Feng
Junhe Feng
XLXiaoming Lu
Xiaoming Lu
Jin-Ming LinJin-Ming Lin
Jin-Ming Lin
A method was developed for the separation of imazethapyr enantiomers using capillary electrophoresis and large volume injection. Optimized buffer conditions were found using 6% hydroxypropyl-β-cyclodextrin as the chiral selector at pH 11 with an injection time of 20 s (0.5 psi). The limits of detection (LOD, S/N = 3) were 0.22 and 0.23 mg L−1 for the two imazethapyr enantiomers (imazethapyr-I and imazethapyr-II) respectively. The relative standard deviation was less than 5%. This method was successfully used in the study of enantioselective degradation of this herbicide in field soil and the results suggested that imazethapyr-I degraded at a higher rate when compared with imazethapyr-II.

27 April 2022 in Journal of Resources and Ecology
Verified
Journal Article
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CSChen Shuanglong
Chen Shuanglong
Wei SongWei Song
Wei Song
LYLiu Yuanzhe
Liu Yuanzhe
HLHan Li
Han Li
Cropland abandonment is spreading from developed countries to developing countries such as China. Cropland abandonment in China commonly occurs in mountainous areas due to their specific natural and geographical conditions. However, due to the lack of dependable monitoring methods via medium-high-resolution remote sensing images, the scale of abandoned cropland in many mountainous areas of China is unclear, and the mechanisms driving cropland abandonment have not been clearly identified. To overcome these limitations, we took Zhong County of Chongqing in China as an example, and used Landsat 8 OLI_TIRS remote sensing image data to develop a method for mapping abandoned cropland in mountainous areas based on annual land use change monitoring. At the same time, the ridge regression method was adopted to analyze the factors influencing cropland abandonment. These analyses showed that the cropland abandonment rate in Zhong County of Chongqing was as high as 7.86%, while the overall accuracy of identifying abandoned cropland was as high as 90.82%. Among the social and economic factors that affect cropland abandonment, the rural population, economic development, and livestock husbandry development were the most important ones. At the land parcel scale, large-scale cropland abandonment occurred in areas at elevations above 650 m or with slopes of more than 15°.