Characterization of elevation and land cover dependent trends of NDVI variations in the Hexi region, northwest China

2019 ◽  
Vol 232 ◽  
pp. 1037-1048 ◽  
Author(s):  
Jing-Cheng Han ◽  
Yuefei Huang ◽  
Hua Zhang ◽  
Xiaofeng Wu
Keyword(s):  
Land Cover ◽  
Northwest China ◽  
Hexi Region

scholarly journals Analysis of land cover change and its driving forces in a desert oasis landscape of Xinjiang, northwest China

Solid Earth ◽  
2014 ◽  
Vol 5 (2) ◽  
pp. 1071-1085 ◽  
Author(s):  
T. Amuti ◽  
G. Luo
Keyword(s):  
Land Cover ◽  
Land Degradation ◽  
Driving Forces ◽  
Northwest China ◽  
Landsat Images ◽  
Desert Oasis ◽  
Standard Classification ◽  
Effects Of Drought ◽  
Arid Desert ◽  
Southern Xinjiang

Abstract. The combined effects of drought, warming and the changes in land cover have caused severe land degradation for several decades in the extremely arid desert oases of southern Xinjiang, northwest China. Land cover classifications of Landsat images in 1990, 2000 and 2008 were performed based on the multistage supervised classification scheme using the maximum likelihood classifier integrated with conventional vegetation and soil indexes, which improved overall accuracies by 4–5% compared to the standard classification method. Based on the detection of changes in land cover during 1990–2008 using remote sensing (RS) and a geographic information system (GIS), it can be found that the oasis significantly (+35%) increased, while the area of ecotone decreased (−43%). The major trends of the land cover changes were the notable growth of the oasis and the reduction of the desert–oasis ecotone. These changes were mainly a result of the intensified human activities such as land and water exploitation as well as overgrazing. The results of this study indicate that the oasis environment will be deteriorated by increase in potential areas of land degradation if the trend of desert moving further inward and the shrinking of the ecotone continues over the next decades.

Integration of Satellite Remote Sensing Techniques and Landscape Metrics to Characterize Land Cover Change and Dynamics

2013 ◽  
pp. 228-244
Author(s):  
Carmelo Riccardo Fichera ◽  
Giuseppe Modica ◽  
Maurizio Pollino
Keyword(s):  
Remote Sensing ◽  
Land Cover ◽  
Landscape Metrics ◽  
Landsat Images ◽  
Aerial Photos ◽  
Multi Temporal ◽  
Urban Rural ◽  
Remote Sensing Techniques

One of the most relevant applications of Remote Sensing (RS) techniques is related to the analysis and the characterization of Land Cover (LC) and its change, very useful to efficiently undertake land planning and management policies. Here, a case study is described, conducted in the area of Avellino (Southern Italy) by means of RS in combination with GIS and landscape metrics. A multi-temporal dataset of RS imagery has been used: aerial photos (1954, 1974, 1990), Landsat images (MSS 1975, TM 1985 and 1993, ETM+ 2004), and digital orthophotos (1994 and 2006). To characterize the dynamics of changes during a fifty year period (1954-2004), the approach has integrated temporal trend analysis and landscape metrics, focusing on the urban-rural gradient. Aerial photos and satellite images have been classified to obtain maps of LC changes, for fixed intervals: 1954-1985 and 1985-2004. LC pattern and its change are linked to both natural and social processes, whose driving role has been clearly demonstrated in the case analysed. In fact, after the disastrous Irpinia earthquake (1980), the local specific zoning laws and urban plans have significantly addressed landscape changes.

Increased evapotranspiration from land cover changes intensified water crisis in an arid river basin in northwest China

2019 ◽  
Vol 574 ◽  
pp. 383-397 ◽  
Author(s):  
Yaoliang Chen ◽  
Shusen Wang ◽  
Zhiguo Ren ◽  
Jingfeng Huang ◽  
Xiuzhen Wang ◽  
...  
Keyword(s):  
Land Cover ◽  
River Basin ◽  
Northwest China ◽  
Land Cover Changes ◽  
Water Crisis

Impacts of Topography on the Land Cover Classification in the Qilian Mountains, Northwest China

2020 ◽  
Vol 46 (3) ◽  
pp. 344-359 ◽  
Author(s):  
Hong Wang ◽  
Chenli Liu ◽  
Fei Zang ◽  
Jianhong Yang ◽  
Na Li ◽  
...  
Keyword(s):  
Land Cover ◽  
Land Cover Classification ◽  
Northwest China ◽  
Qilian Mountains ◽  
The Qilian Mountains

scholarly journals Prevalence and molecular characterization of Cryptosporidium spp. and Giardia duodenalis in dairy cattle in Gansu, northwest China

Parasite ◽  
2020 ◽  
Vol 27 ◽  
pp. 62
Author(s):  
Yilin Wang ◽  
Jianke Cao ◽  
Yankai Chang ◽  
Fuchang Yu ◽  
Sumei Zhang ◽  
...  
Keyword(s):  
Dairy Cattle ◽  
Ribosomal Rna ◽  
Triosephosphate Isomerase ◽  
Giardia Duodenalis ◽  
Northwest China ◽  
Small Subunit ◽  
Gastrointestinal Parasites ◽  
Rrna Gene ◽  
And Control

Cryptosporidium spp. and Giardia duodenalis are common gastrointestinal parasites with a broad range of hosts, including humans, livestock, and wildlife. To examine the infection status and assess the zoonotic potential of Cryptosporidium spp. and G. duodenalis in dairy cattle in Gansu, China, a total of 1414 fecal samples were collected from the rectum, with one sample collected from each individual animal. All the samples were tested using nested PCR based on the small subunit ribosomal RNA (SSU rRNA) gene of Cryptosporidium spp. and G. duodenalis. The overall infection rates of Cryptosporidium spp. and Giardia duodenalis were 4.2% (n = 59) and 1.0% (n = 14), respectively. Four Cryptosporidium species were identified: C. andersoni (n = 42), C. parvum (n = 12), C. bovis (n = 5), and C. ryanae (n = 1). In further analyses of subtypes of C. parvum isolates based on the 60 kDa glycoprotein (gp60) gene, five were successfully subtyped as IIdA19G1 (n = 4) and IIdA15G1 (n = 1). All 14 G. duodenalis isolates were identified as assemblage E using the triosephosphate isomerase (tpi) gene. The relatively low positive rates of Cryptosporidium spp. and G. duodenalis detected here and the predominance of non-human pathogenic species/assemblages of these parasites indicated their unique transmission dynamics in this area and the low level of threat posed to public health. However, continuous monitoring and further studies of these parasites should be conducted for the prevention and control of these pathogens.

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