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Assessment and dynamic changes of environmental vulnerability at county level: a case study in Kenli County of the Yellow River Delta, China

WANG Rui-Yan,ZHAO Geng-Xing,ZHOU Wei,JIANG Shu-Qian,QIN Yuan-Wei,

生态学报 , 2009,
Abstract: The environmental vulnerability has been the issue in the field of international environment, but such domestic study is few. As county is the basic regional units characterized with regional, spatial and administrational independence in china, assessment of the environmental vulnerability at county level is a matter of importance. Based on the requirement of environment management, focused on county level, this paper clarified the attribute of environmental vulnerability, selected evaluation indexes from three aspects of stability, sensitivity and applicability, and established the evaluation models so as to systematically assess environmental vulnerability within county area. The results indicated that the environmental stability of Kenli County was instable, the environmental sensitivity appeared a descend trend and the environmental adaptability showed an uptrend as a whole during 1986-2003. The partial correlation method was adopted to analyze the natural factor sensitivity of Kenli County, and their sensitivity sequence was that the groundwater level>evaporation and precipitation ratio>groundwater salinity>air temperature. Therefore, the natural sensitive factors of the study area were determined as the former three. The results of obstacle degree of regional adaptability indicated that the saline\|alkali soil amelioration rate was the most important obstacle factor during 1986-2003, the restriction of the farmland shelter\|forest density mainly appeared during 1995-1998, and the pesticide and fertilization application became the main obstacle since 2000, and the effective irrigation area ratio and the drainage system area ratio raised as the problem before 1990. The conclusions are that the environmental vulnerability of Kenli County is declining,but still in vulnerable state. At the same time, Kenli County should put the emphases on the development of the sensitive and obstacle factors. The assessment method can find the fundamental reasons and the development process of the County environmental vulnerability, which is significant for the current domestic study.
Information Extraction Method of Soil Salinity in Typical Areas of the Yellow River Delta Based on Landsat Imagery  [PDF]
Tongrui Zhang, Gengxing Zhao, Chunyan Chang, Zhuoran Wang, Ping Li, Deyu An, Jichao Jia
Agricultural Sciences (AS) , 2015, DOI: 10.4236/as.2015.61006
Abstract: In order to get RS method to extract soil salinity of the Yellow River Delta, we set Kenli County as typical Yellow River Delta to be research area and get data of soil salinity through field investigation. By using RS image of Landsat-8 of March 14, 2014 and analyzing information features of each band and surface spectral features of research areas, we select out sensitive bands and build Soil Salinity Information Extraction (SSIE) model and vegetation index NDVI model for comparison. And then, we accordingly classify grades of soil salinity and get soil salinity information by decision tree approach based on expert knowledge. The results show that overall accuracy of SSIE model is 93.04% and coefficient of Kappa is 0.7869, while overall accuracy of NDVI model is 83.67% and coefficient of Kappa is 0.7017 respectively. By comparing with measured proportions of each class, we see that results from SSIE model is more accurate, which indicates significant advantage for soil salinity information extraction. This research provides scientific basis to get and monitoring soil salinity of the Yellow River Delta region quickly and accurately.
Properties of saline-alkaline soil under different land use types in Yellow River Delta

LI Qing-Mei,HOU Long-Yu,LIU Yan,MA Feng-Yun,
,侯龙鱼,刘 艳,马风云

中国生态农业学报 , 2009,
Abstract: n order to allviate saline-alkaline property of soils for sustainable soil utilization, the properties of soils under the four land use types of wasteland, cotton land, clover land and pear orchard were analyzed. The analysis reveals the following: 1) In cotton lands, there is increasing soil bulk density, decreasing soil porosity and capillarity porosity, and rising water tables driven by the mode of irrigation which induces heavy salt return to soil surface. 2) In clover lands, there is decreasing soil organic matter and other nutrients, and soil physical properties are better with lower salinity due to less human disturbance. On other hand, azotobacter of legume increases the available nitrogen content in surface soil. 3) In pear orchards which are usually planted in areas with better soil quality, soil physical properties are better and salinity is lower than those in cotton lands, driven by the application of organic fertilizer such as animal manure. 4) In waster lands, soil properties are better than in cotton land, land recovering from degenerating cotton lands is feasible.
Daily change of primary productivity of phytoplankton in saline-alkaline ponds

ZHAO Wen,DONG Shuang Lin,ZHANG Zhaoqi,SHENTU Qingchun,

应用生态学报 , 2003,
Abstract: Daily change of the primary productivity of phytoplankton in saline-alkaline ponds in Zhaodian Fishery Farm, Gaoqing County, Shandong Province, were estimated by means of dark and light bottle method, at the season of fish growth from April to September in 1997. The results showed that the primary productivity of phytoplankton in saline-alkaline ponds presents significant change during a day. And their distribution were correlated with some environmental factors such as light intensity, water temperature, the chlorophyll-a concentration etc. The measured values of primary production in continual exposure for 24 hour with dark and light bottle methods were greatly lower than the accumulated values of exposure for 2 hour. It is proposed that diurnal production calculated by the results of exposure for 4 hour between 10:00 and 14:00 was suitable in fish-culture ponds.
Degradation of pyrene by immobilized microorganisms in saline-alkaline soil
Shanxian Wang,Xiaojun Li,Wan Liu,Peijun Li,Lingxue Kong,Wenjie Ren,Haiyan Wu,Ying Tu,
Shanxian Wang
,Xiaojun Li,Wan Liu,Peijun Li,Lingxue Kong,Wenjie Ren,Haiyan Wu,Ying Tu

环境科学学报(英文版) , 2012,
Abstract: Biodegradation of polycyclic aromatic hydrocarbons (PAHs) is very difficult in saline-alkaline soil due to the inhibition of microbial growth under saline-alkaline stress. The microorganisms that can most effectively degrade PAHs were screened by introducing microorganisms immobilized on farm byproducts and assessing the validity of the immobilizing technique for PAHs degradation in pyrene-contaminated saline-alkaline soil. Among the microorganisms examined, it was found that Mycobacterium sp. B2 is the best, and can degrade 82.2% and 83.2% of pyrene for free and immobilized cells after 30 days of incubation. The immobilization technique could increase the degradation of pyrene significantly, especially for fungi. The degradation of pyrene by the immobilized microorganisms Mucor sp. F2, fungal consortium MF and co-cultures of MB+MF was increased by 161.7% (P < 0.05), 60.1% (P < 0.05) and 59.6% (P < 0.05) after 30 days, respectively, when compared with free F2, MF and MB+MF. Scanning electron micrographs of the immobilized microstructure proved the positive effects of the immobilized microbial technique on pyrene remediation in saline-alkaline soil, as the interspace of the carrier material structure was relatively large, providing enough space for cell growth. Co-cultures of different bacterial and fungal species showed different abilities to degrade PAHs. The present study suggests that Mycobacterium sp. B2 can be employed for in situ bioremediation of PAHs in saline-alkaline soil, and immobilization of fungi on farm byproducts and nutrients as carriers will enhance fungus PAH-degradation ability in saline-alkaline soil.
Investigation of the Vegetation on Saline-alkaline Soils and Marshes of Igdir Plain in Turkey  [PDF]
A. Istanbulluoglu
Pakistan Journal of Biological Sciences , 2004,
Abstract: This study involves in the investigation of halophytic vegetation in Igdir Plain which comprises of partly summer drying and partly prominent saline and alkaline marshes, located near Ararat Mountain in the Eastern Turkey. Six associations and three sub-associations were identified in the plain. Arthrocnemetum glaucum, Halimiono-Arthrocnemetum glaucum and Halocnemo-Salsoletum macrae associations were described in the area where the soil surface was covered by a white salt crust accompanying with extremely sodium, boron and lime contents. Junco-Puccinellietum distans association was widespread in the waterlogged marshes area of the plain while Panderino-Tamericetum parviflorae association prevailed on the soils containing small amount of salt and lime, and having no alkalinity and acidity problem (i.e. neutral in pH). Kochio-Schismetum arabicus was seen in the soil showing the characteristics of no salinity and low alkalinity problem and containing small amount of lime. This area was the transition zone between the wind erosion and highly saline and alkaline soils. All these associations, except Arthrocnemetum glaucum, were described in this study for the first time. Junco-Puccinelliatum distans association was included in Puccinellio-Salicornion europae alliance of Salsola-Aeluropetalia litoralli order. The other associations were grouped under Alhagio-Suaedion microphyllae alliance that was identified in this study for the first time.
Isolation and Identification of Myxobacteria from Saline-Alkaline Soils in Xinjiang, China  [PDF]
Xianjiao Zhang, Qing Yao, Zhuoping Cai, Xiaolin Xie, Honghui Zhu
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0070466
Abstract: Fifty-eight terrestrial and salt-tolerant myxobacteria were isolated from the saline-alkaline soils collected from Xinjiang, China. Based on the morphologies and the 16S rRNA gene sequences, these isolates were assigned into 6 genera, Myxococcus, Cystobacter, Corallococcus, Sorangium, Nannocystis and Polyangium. All the strains grew better with 1% NaCl than without NaCl. Some Myxococcus strains were able to grow at 2% NaCl concentration, suggesting that these strains may be particular type of terrestrial myxobacteria.

Chen Zhiliang,

第四纪研究 , 2007,
Abstract: The Hajiang saline pool in the source area of the Yellow River is located in Madoi County, Qinghai Province, at 36.42°N, 99.06°E. It was considered as the starting place of the ancient Qiang people who migrated from grasslands in the northeastern Qinghai-Tibet Plateau to the Chengdu Plain in the Upper Ancient Age. Then, the ancient Qiang people created the San Xing Dui and Jin Sha cultures in Chengdu and the adjacent area. According to the analyses of geomorphological evolution and related climatic variation, it is suggested that the developmental process of the Hajiang saline pool may be divided into two stages: the paleo-lake stage and the saline lake stage. In the first stage, the Yellow River incised into the Duoshixia Gorge from the east to the west and stretched up to the Source Area, as the results of headward erosion and river capture since ca.7000aB.P. The Hajiang paleo-lake lost its major water supply from mountains of the north side. Although late development of this stage made the Hajiang paleo-lake into a half-closed lake, it is suggested that the lake was not a saline lake under warm-humid climate during that age(equal to the "Atlantic Period" or the "Altithermal Period"). The Hajiang paleo-lake later became a half-dry saline lake because of the Middle Holocene climatic change("Mid-Holocene transition")from warm-humid to cold-dry and a series of climatic events since 5500aB.P. , especially the great cold-dry event (equal to "IRD(ice-rafted debris) event 3",or "Holocene event 3")at ca.4500aB.P.The geomorphological evolution and climatic variation not only resulted in the formation of the saline pool, but also compelled the ancient Qiang people to migrate to lower and warmer places, among which the valleys in the eastern margin of the Plateau and the Chengdu Plain were the best choices. The formation of the Hajiang saline pool made it possible for local residents to develop an ancient salt industry to exchange salt with others from the adjacent area, which helps their migration from the plateau to the plain.
Transcriptome Exploration in Leymus chinensis under Saline-Alkaline Treatment Using 454 Pyrosequencing  [PDF]
Yepeng Sun, Fawei Wang, Nan Wang, Yuanyuan Dong, Qi Liu, Lei Zhao, Huan Chen, Weican Liu, Hailong Yin, Xiaomei Zhang, Yanxi Yuan, Haiyan Li
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0053632
Abstract: Background Leymus chinensis (Trin.) Tzvel. is a high saline-alkaline tolerant forage grass genus of the tribe Gramineae family, which also plays an important role in protection of natural environment. To date, little is known about the saline-alkaline tolerance of L. chinensis on the molecular level. To better understand the molecular mechanism of saline-alkaline tolerance in L. chinensis, 454 pyrosequencing was used for the transcriptome study. Results We used Roche-454 massive parallel pyrosequencing technology to sequence two different cDNA libraries that were built from the two samples of control and under saline-alkaline treatment (optimal stress concentration-Hoagland solution with 100 mM NaCl and 200 mM NaHCO3). A total of 363,734 reads in control group and 526,267 reads in treatment group with an average length of 489 bp and 493 bp were obtained, respectively. The reads were assembled into 104,105 unigenes with MIRA sequence assemable software, among which, 73,665 unigenes were in control group, 88,016 unigenes in treatment group and 57,576 unigenes in both groups. According to the comparative expression analysis between the two groups with the threshold of “log2 Ratio ≥1”, there were 36,497 up-regulated unegenes and 18,218 down-regulated unigenes predicted to be the differentially expressed genes. After gene annotation and pathway enrichment analysis, most of them were involved in stress and tolerant function, signal transduction, energy production and conversion, and inorganic ion transport. Furthermore, 16 of these differentially expressed genes were selected for real-time PCR validation, and they were successfully confirmed with the results of 454 pyrosequencing. Conclusions This work is the first time to study the transcriptome of L. chinensis under saline-alkaline treatment based on the 454-FLX massively parallel DNA sequencing platform. It also deepened studies on molecular mechanisms of saline-alkaline in L. chinensis, and constituted a database for future studies.
Storage/Turnover Rate of Inorganic Carbon and Its Dissolvable Part in the Profile of Saline/Alkaline Soils  [PDF]
Yugang Wang, Zhongyuan Wang, Yan Li
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0082029
Abstract: Soil inorganic carbon is the most common form of carbon in arid and semiarid regions, and has a very long turnover time. However, little is known about dissolved inorganic carbon storage and its turnover time in these soils. With 81 soil samples taken from 6 profiles in the southern Gurbantongute Desert, China, we investigated the soil inorganic carbon (SIC) and the soil dissolved inorganic carbon (SDIC) in whole profiles of saline and alkaline soils by analyzing their contents and ages with radiocarbon dating. The results showed that there is considerable SDIC content in SIC, and the variations of SDIC and SIC contents in the saline soil profile were much larger than that in the alkaline profile. SDIC storage accounted for more than 20% of SIC storage, indicating that more than 1/5 of the inorganic carbon in both saline and alkaline soil is not in non-leachable forms. Deep layer soil contains considerable inorganic carbon, with more than 80% of the soil carbon stored below 1 m, whether for SDIC or SIC. More importantly, SDIC ages were much younger than SIC in both saline soil and alkaline soil. The input rate of SDIC and SIC ranged from 7.58 to 29.54 g C m-2 yr-1 and 1.34 to 5.33 g C m-2 yr-1 respectively for saline soil, and from 1.43 to 4.9 g C m-2 yr-1 and 0.79 to 1.27 g C m-2 yr-1respectively for alkaline soil. The comparison of SDIC and SIC residence time showed that using soil inorganic carbon to estimate soil carbon turnover would obscure an important fraction that contributes to the modern carbon cycle: namely the shorter residence and higher input rate of SDIC. This is especially true for SDIC in deep layers of the soil profile.
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