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<article language="en">
	<journal>
		<journal_title>Hydrology and Earth System Sciences</journal_title>
		<journal_url>www.hydrol-earth-syst-sci.net</journal_url>
		<issn>1027-5606</issn>
		<eissn>1607-7938</eissn>
		<volume_number>13</volume_number>
		<issue_number>7</issue_number>
		<publication_year>2009</publication_year>
	</journal>
	<doi>10.5194/hess-13-1375-2009</doi>
	<article_url>http://www.hydrol-earth-syst-sci.net/13/1375/2009/</article_url>
	<abstract_html>http://www.hydrol-earth-syst-sci.net/13/1375/2009/hess-13-1375-2009.html</abstract_html>
	<fulltext_pdf>http://www.hydrol-earth-syst-sci.net/13/1375/2009/hess-13-1375-2009.pdf</fulltext_pdf>
	<start_page>1375</start_page>
	<end_page>1398</end_page>
	<publication_date>2009-07-31</publication_date>
	<article_title content_type="html">Temporal variation of soil moisture over the Wuding River basin assessed with an eco-hydrological model, in-situ observations and remote sensing</article_title>
	<authors>
		<author numeration="1" affiliations="1">
			<name>S. Liu</name>
			<email>liusx@igsnrr.ac.cn</email>
		</author>
		<author numeration="2" affiliations="1">
			<name>X. Mo</name>
		</author>
		<author numeration="3" affiliations="2">
			<name>W. Zhao</name>
		</author>
		<author numeration="4" affiliations="3">
			<name>V. Naeimi</name>
		</author>
		<author numeration="5" affiliations="2">
			<name>D. Dai</name>
		</author>
		<author numeration="6" affiliations="1">
			<name>C. Shu</name>
		</author>
		<author numeration="7" affiliations="4">
			<name>L. Mao</name>
		</author>
	</authors>
	<affiliations>
		<affiliation numeration="1" content_type="html">Key Laboratory of Water Cycle &amp; Related Land Surface Processes, Institute of Geographic Sciences &amp; Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China</affiliation>
		<affiliation numeration="2" content_type="html">The Bureau of Hydrology, Yellow River Conservancy Committee, Zhengzhou, 450004, China</affiliation>
		<affiliation numeration="3" content_type="html">Institute of Photogrammetry and Remote Sensing, Vienna University of Technology, Gusshausstrasse 27–29, 1040 Vienna, Austria</affiliation>
		<affiliation numeration="4" content_type="html">China Meteorology Administration, National Meteorological Center, Beijing, 100081, China</affiliation>
	</affiliations>
	<abstract content_type="html">The change pattern and trend of soil moisture (SM) in the Wuding River basin,
Loess Plateau, China is explored based on the simulated long-term SM data from 1956 to
2004 using an eco-hydrological process-based model, Vegetation
Interface Processes model, VIP. In-situ SM observations together with a remotely sensed SM dataset retrieved by the Vienna
University of Technology are used to validate the model.
In the VIP model, climate-eco-hydrological (CEH) variables such as precipitation, air
temperature and runoff observations and also simulated evapotranspiration (&lt;I&gt;E&lt;sub&gt;T&lt;/sub&gt;&lt;/I&gt;), leaf area
index (LAI), and vegetation production are used to analyze
the soil moisture evolution mechanism. The results show that the model is able to capture
seasonal SM variations. The seasonal pattern, multi-year variation, standard
deviation and coefficient of variation (&lt;I&gt;C&lt;sub&gt;V&lt;/sub&gt;&lt;/I&gt;) of SM at the daily, monthly and
annual scale are well explained by CEH variables. The annual and
inter-annual variability of SM is the lowest compared with that of other CEH
variables. The trend analysis shows that SM is in decreasing tendency at
α=0.01 level of significance, confirming the Northern Drying phenomenon. This trend
can be well explained by the decreasing tendency of precipitation (α=0.1) and
increasing tendency of temperature (α=0.01). The
decreasing tendency of runoff has higher significance level (α=0.001).
Because of SM&apos;s decreasing tendency, soil evaporation (&lt;I&gt;E&lt;sub&gt;S&lt;/sub&gt;&lt;/I&gt;) is also decreasing
(α=0.05). The tendency of net radiation (&lt;I&gt;R&lt;sub&gt;n&lt;/sub&gt;&lt;/I&gt;),
evapotranspiration (&lt;I&gt;E&lt;sub&gt;T&lt;/sub&gt;&lt;/I&gt;), transpiration (&lt;I&gt;E&lt;sub&gt;C&lt;/sub&gt;&lt;/I&gt;), canopy intercept
(&lt;I&gt;E&lt;sub&gt;I&lt;/sub&gt;&lt;/I&gt;) is not obvious. Net primary
productivity (NPP), of which the significance level is lower than α=0.1,
and gross primary productivity (GPP) at α=0.01 are in increasing
tendency.</abstract>
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