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    <identifier>10.57760/sciencedb.02345</identifier>
    <datestamp>2022-08-23T08:47:31Z</datestamp>
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  <dc:date>2022-08-23</dc:date>
  <dc:title>Spatial Variability of Contents of Nicotine in Flue-cured Tobacco Leaves and and Soil  Medium and Trace Elements in Tobacco Planting Fields in Central Henan province, China</dc:title>
  <dc:identifier>doi:10.57760/sciencedb.02345</dc:identifier>
  <dc:language>en</dc:language>
  <dc:description>&amp;nbsp;Collection and measurement of soil and tobacco leaf samples1.1 Sample collecting methodIn early June 2021, soil samples and flue-cured tobacco leaf samples were collected from tobacco planting fields in Pingdingshan, Xuchang and Luohe, Henan Province. The annual planting area of flue-cured tobacco in the study area is 3.67&amp;times;10 5 hm2&amp;nbsp;. Sampling points must have representation and homogeneity. In the tobacco&amp;nbsp;planting&amp;nbsp;area, a mixed soil sample was collected every 33.3km2 , and in the low hilly land of tobacco-growing area, a mixed soil sample was collected every 20.00km2 . Using handheld GPS position indicator, to collect samples from multiple points in a circular area with a radius of 10 m. Collected about 1 kg of soil samples from the plough layer (0-20 cm) and brought them back to the laboratory, also collected leaf sample correspondingly (tobacco plants from 8 to 12 leaf from top to bottom, each 2.5kg). A total of 1259 soil samples were collected.1.2 Measurement methodThe contents of nicotine were determined by ultraviolet spectrophotometry (Wang RX.&amp;nbsp;2003). The contents of medium and trace elements of soils in tobacco planting fields were determined by microwave digestion-flame atomic absorption spectrometry (Zhang et al. 2010).1.3 Data analysis methodGeostatistical method: using the relevant parameters of the semivariance function to analyze the spatial structure of the nicotine content in tobacco leaves and soil&amp;nbsp;medium and trace elements in soils of tobacco planting fields in the study area&amp;nbsp;(&amp;nbsp;Miressa Duffera&amp;nbsp;et al. 2007).Software platform:(1) SPSS10.0: descriptive statistical analysis;(2) GS+5.3: Semivariance function analysis&amp;nbsp;(&amp;nbsp;Miressa Duffera&amp;nbsp;et al. 2007; Liu et al.&amp;nbsp;2009).(3) ArcGIS: digital map, Kriging interpolation&amp;nbsp;(Rodriguez Martin et al. 2007; Zhao&amp;nbsp;et al.&amp;nbsp;2011).</dc:description>
  <dc:subject>geostatistics; spatial variability; nicotine; soil medium and trace elements</dc:subject>
  <dc:creator>Jinlan Yao</dc:creator>
  <dc:rights>PUBLIC</dc:rights>
  <dc:rights>https://creativecommons.org/publicdomain/zero/1.0/</dc:rights>
  <dc:type>dataset</dc:type>
  <dc:publisher>Science Data Bank</dc:publisher>
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