Wetlands in the Jiuzhaigou World Natural Heritage site of south-west China: classification and recent changes

2018 ◽  
Vol 69 (5) ◽  
pp. 677 ◽  
Author(s):  
Jie Du ◽  
Xue Qiao ◽  
Meng Zhang ◽  
Baofeng Di ◽  
Ya Tang
Keyword(s):  
Debris Flows ◽  
Heavy Rain ◽  
Storm Events ◽  
Key Factors ◽  
West China ◽  
South West ◽  
Heritage Site ◽  
Increasing Trend ◽  
Commercial Logging ◽  
Water Nutrients

To understand the effects of tourism and climate change on wetlands, a study was performed at Jiuzhaigou, a destination receiving >5 million people per year. There are 21 types of wetlands in region, covering an area of 265.1ha, with 42.8% on tufa. Wetland areas declined by 16.1% from 1983 to 1999 (autumn) and by 31.2% from 1983 to 2002 (summer) and increased by 31.8% from 1999 to 2011 (autumn) and by 60% from 2002 to 2014 (summer). Wetland changes included dissolving tufa, a reduced tufa deposit rate, collapse of tufa mats, increases in water nutrients and algae, and marshland development. Mean annual air temperature increased from 1977. Annual precipitation varied from 430 to 810mm between 1951 and 2015, exhibiting an increasing trend from 2005 onwards. The number of both heavy rain and storm events increased from 2005. The number of tourists grew slowly from 1984 to 1997, but increased quickly from 360000 in 1998 to 5.1 million in 2015. Commercial logging between 1966 and 1978 and debris flows are probably the key factors contributing to increased lake sedimentation and marshland development. Rapid tourism development with intensive bus movement and regional air pollution likely caused changes in water chemistry, which, in turn, caused tufa changes and wetland degradation. Reducing tourist numbers is likely to be effective in reducing effects on wetlands and conserving them, but research is needed to determine appropriate tourist numbers.

Hazard assessment of debris flows in the Wenchuan earthquake-stricken area, South West China

Landslides ◽  
2017 ◽  
Vol 14 (5) ◽  
pp. 1783-1792 ◽  
Author(s):  
Ming Chang ◽  
Chuan Tang ◽  
Th. W. J. Van Asch ◽  
Fei Cai
Keyword(s):  
Wenchuan Earthquake ◽  
Hazard Assessment ◽  
Debris Flows ◽  
West China ◽  
The Wenchuan Earthquake ◽  
South West

Three mutations analysis of glucose-6-phosphate dehydrogenase deficiency in neonates in South-west China

2007 ◽  
Vol 49 (4) ◽  
pp. 463-467
Author(s):  
CHUN DENG ◽  
CHUN-BAO GUO ◽  
YOU-HUA XU ◽  
BING DENG ◽  
JIA-LIN YU
Keyword(s):  
Dehydrogenase Deficiency ◽  
West China ◽  
South West ◽  
Glucose 6 Phosphate Dehydrogenase

scholarly journals Lysinibacillus antri sp. nov., isolated from cave soil

2020 ◽  
Vol 70 (5) ◽  
pp. 3295-3299 ◽  
Author(s):  
Manik Prabhu Narsing Rao ◽  
Zhou-Yan Dong ◽  
Xue-Ke Niu ◽  
Kun Zhang ◽  
Ying-Qian Kang ◽  
...  
Keyword(s):  
Cell Wall ◽  
Novel Species ◽  
Guizhou Province ◽  
Species Delineation ◽  
Gram Stain ◽  
West China ◽  
Content Type ◽  
South West ◽  
Optimum Ph ◽  
Genome Comparisons

A Gram-stain-positive, motile, rod-shaped and endospore-forming strain, SYSU K30002T, was isolated from a soil sample collected from a karst cave in Xingyi county, Guizhou province, south-west China. SYSU K30002T grew at 28–40 °C (optimum, 37 °C), at pH 5.0–8.0 (optimum, pH 7.0) and in the presence of 0–4 % (w/v) NaCl (optimum in the absence of NaCl). The cell-wall peptidoglycan type was A4α (Lys–Asp). The cell-wall sugars of SYSU K30002T were ribose, galactose and mannose, and MK-7 was the menaquinone. The major fatty acids were iso-C15 : 0, C16 : 1 ω7c alcohol and iso-C16 : 0. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and two unidentified phospholipids. The G+C content of the genomic DNA was 36.1 mol%. The average nucleotide identity values between SYSU K30002T and its closest relatives were below the cut-off level (95–96 %) for species delineation. Based on phenotypic, chemotaxonomic and genome comparisons, strain SYSU K30002T represents a novel species of the genus Lysinibacillus , for which the name Lysinibacillusantri sp. nov. is proposed. The type strain is SYSU K30002T (=KCTC 33955T=CGMCC 1.13504T).

scholarly journals Propagation Characteristics of Debris Flows Considering Entrainment Effect

2018 ◽  
Vol 7 (3.34) ◽  
pp. 122
Author(s):  
Seokil Jeong ◽  
Junseon Lee ◽  
Chang Geun Song ◽  
Seung Oh Lee
Keyword(s):  
Debris Flow ◽  
Debris Flows ◽  
Flow Behavior ◽  
Prediction Method ◽  
Heavy Rain ◽  
Accurate Analysis ◽  
Propagation Length ◽  
2D Simulation ◽  
Entrainment Effect ◽  
The Relationship

Background/Objectives: Due to the extreme climate and the localized heavy rain, the frequency of debris flow has been increasing. Therefore, there is a growing expectation for accurate numerical analysis.Methods/Statistical analysis: We present a prediction method that can calculate the propagation length of the debris flow. This analysis indicates the relationship between the potential energy and the propagation length of the debris flow. To study the behavior of the debris flow accurately, the change in the momentum force must be considered; otherwise the calculation accuracy of the debris flow behavior is inevitably low.Findings: Entrainment is a common behavior in a debris flow that leads to changes in the momentum force. Here, we analyzed the change in the momentum force using a 2D simulation model that included entrainment. The results show how the debris flow behaves with changes in the momentum force. When entrainment is considered, the propagation length tends to be underestimated. With detailed information, the uncertainty in the prediction accuracy can be reduced.Improvements/Applications: If studies on the material properties of debris flow would be added, it will be possible to carry out various and accurate analysis of the debris flow  

Clinical features of amyotrophic lateral sclerosis in south-west China

2015 ◽  
Vol 16 (7-8) ◽  
pp. 512-519 ◽  
Author(s):  
Qianqian Wei ◽  
Xueping Chen ◽  
Zhenzhen Zheng ◽  
Rui Huang ◽  
Xiaoyan Guo ◽  
...  
Keyword(s):  
Amyotrophic Lateral Sclerosis ◽  
Clinical Features ◽  
West China ◽  
South West ◽  
Lateral Sclerosis

scholarly journals Adaptive and High-Resolution Estimation of Specific Differential Phase for Polarimetric X-Band Weather Radars

2018 ◽  
Vol 35 (3) ◽  
pp. 555-573 ◽  
Author(s):  
Ricardo Reinoso-Rondinel ◽  
Christine Unal ◽  
Herman Russchenberg
Keyword(s):  
Standard Deviation ◽  
Spatial Variability ◽  
Heavy Rain ◽  
Storm Events ◽  
Band Frequency ◽  
Adaptive Approach ◽  
Range Resolution ◽  
Differential Phase ◽  
Weather Radars ◽  
X Band

ABSTRACTOne of the most beneficial polarimetric variables may be the specific differential phase KDP because of its independence from power attenuation and radar miscalibration. However, conventional KDP estimation requires a substantial amount of range smoothing as a result of the noisy characteristic of the measured differential phase ΨDP. In addition, the backscatter differential phase δhv component of ΨDP, significant at C- and X-band frequency, may lead to inaccurate KDP estimates. In this work, an adaptive approach is proposed to obtain accurate KDP estimates in rain from noisy ΨDP, whose δhv is of significance, at range resolution scales. This approach uses existing relations between polarimetric variables in rain to filter δhv from ΨDP while maintaining its spatial variability. In addition, the standard deviation of the proposed KDP estimator is mathematically formulated for quality control. The adaptive approach is assessed using four storm events, associated with light and heavy rain, observed by a polarimetric X-band weather radar in the Netherlands. It is shown that this approach is able to retain the spatial variability of the storms at scales of the range resolution. Moreover, the performance of the proposed approach is compared with two different methods. The results of this comparison show that the proposed approach outperforms the other two methods in terms of the correlation between KDP and reflectivity, and KDP standard deviation reduction.

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