Investigating the area and production of poplar plantations in Sowme`eh Sara city using field data and GIS

Due to the scattering of poplar plantations in the city of Sowme`eh Sara, Gilan province and the lack of timely, documentary and scientific information from the current status, it is necessary to determine the exact location of the distribution, area and volume of its poplar plantations. In the present study, area, distribution and status of poplar plantation and biometric statistics of poplar trees in Sowme`eh Sara city and their wood production were measured separately for each village.

First, through field operations, the field of poplar plantations with the Global Positioning System (GPS) and the use of GPS Fields Area Measure PRO application was located and uploaded to Google Earth and the poplar cultivation pattern was determined. After drawing the poplar plantation polygons on Google Earth, they were transferred to ArcGIS and converted to an integrated polygon layer in shp format. After the completion of the map each village, the field control was performed and the biometric information of each section was recorded, including the measuring diameter at breast height and height of trees and then their volume was calculated, and then the distribution map and the total location of the existing poplar plantations in the city were prepared. Also, climate maps of temperature and precipitation this city were drawn by receiving data from three meteorological stations related to the ten-year period (2008-2017) and some soil characteristics of Sowme`eh Sara city were prepared separately for each village related to 0-30 cm depth with 138 harvest points.

The results showed that the total area of poplar plantations in Sowme`eh Sara city is 6,944 ha and Ziaber village with 29.65% is the first grade in the percentage of land allocation to poplar plantation with maximum area of poplar plantation section and the highest number and volume of trees. There are a number of 99 poplar plantations fields with an area of less than 500 m2 and 1584 poplar plantations fields with an area of more than 1 ha, which include 3.22 ha and 5471 ha of poplar plantations areas in this city, respectively. The wood obtained from about 91% of the total area of poplar plantation in the city is dedicated to concentrated cultivation and industrial uses. The highest average diameter at breast height and height of trees in Tolmat village and the lowest of them in Hendukhaleh village were obtained. The results of soil properties showed that the soil texture of the studied villages was mainly loamy-clay texture that is suitable for poplar cultivation and development, but the pH of the soil showed different values in each village.

Considering the total volume of trees in Sowme`eh Sara city with the amount of 3411884 m3, this amount of wood volume can provide about a quarter of the country's annual wood consumption.