The aim of this research is to estimate the level of annual afforested in the west of Gilan province, in order to prepare afforestation map with two approaches of ground and remote sensing and landscape approach. For this purpose, first, by using the capabilities of Google Earth software, the range of each forestry area was determined and prepared in the form of a shape file. Multi-temporal data of Sentinel-2 satellite was used at intervals of 30-40 days. After processing, interpreting, and analyzing the data and preparing the model based on the time series of the data, the model was tested in the pilot areas with information related to the field observations. These images were used to estimate landscape features. In the landscape metrics method, with the help of Sentinel 2 satellite images and two measures of tree cover percentage and NDVI index, the surface and distribution of afforestation were checked and calculated at the level of each county and then according to that, the afforested area was calculated. According to the findings, the total annual afforestation done in the west of Gilan province is 14044 hectares, the county of Soumesara and Rezvanshahr have the most with 4611 and 3315 hectares, respectively, and Foman with 200 hectares, the least per capita. According to the results of this research, 21326 hectares are the total of annual forestry and urban and forest parks in the mentioned cities in the west of Gilan. In determining the level with the landscape approach, the area of afforestation in all the study areas was more than the previous method, and the biggest difference between the two methods was in the cities of Razvanshahr and Soumesara. The results of the comparison of two land surveying and remote sensing approaches showed that although the area of afforestation was obtained with the landscape approach more than the land harvesting and remote sensing methods, but the time, cost and ease of this method are more than other methods. Therefore, the integration of these two methods to determine the area of afforestation is suggested according to the purpose and time and cost of each research.
Key words: forestry, forest park, geographic information system, landscape, West Gilan
Introduction
Forests have a great role in the long-term plans of a country in terms of landscape, history, culture and economy (Cavalli et al., 2022). They contribute significantly to human well-being and provide many ecosystem services, including wood production, carbon storage, food production, soil conservation, climate control, biodiversity conservation, environmental pollution, and hydrological cycle regulation (Spadoni et al., 2020).
Despite the different projects carried out in the west of Gilan province, the information, statistics and location of the hand-planted stands have not been recorded regularly. Also, there is no specific information available about the status of many afforested areas in the following years. Since forestry is considered as one of the indicators of countries' development, it is definitely important to monitor forestry lands to maximize the potential of forestry and guide its development in line with the principles of sustainable forest management. Although forestry includes all the benefits associated with forest ecosystem services, the mismanagement of these lands can cause land fragmentation and challenges such as land use change (Czimczik et al., 2005).
Although there have been scattered studies related to the monitoring and evaluation of afforestation in the country, but the majority of these studies have been in the field of forests and afforestation has been addressed much less; Because the study of forestry is very important for monitoring land changes and represents a central issue in sustainable development approaches, in terms of climate change, monitoring ecosystem services, and planning activities and policies. On the other hand, it is difficult to evaluate growing forests (Cavalli et al., 2022), so the existence of written information about the process of quantitative and qualitative changes in these afforestation is very necessary. In Gilan province, no study has been done in the field of evaluation and monitoring of afforestation, so the most important goal of this research is to evaluate and investigate the areas of afforestation and their distribution in the west of Gilan province using a combination of land data and information system. Geographical and landscape approach is to determine the level and capacity of existing forestry areas.
Materials and methods:
The study area in this research in the west of Gilan province includes 8 cities of Shaft, Foman, Soumesara, Bandar Anzali, Masal, Rezvanshahr, Talesh and Astara. This range is located at latitude 37°12'N and longitude 49°39'E from the Greenwich meridian (Figure 1).


Figure 1- The location of the study area in Gilan province and a picture of afforestation with broadleaf species

By using the capabilities of Google Earth software, the area of each forestry area was determined and prepared in the Arc map software environment in the form of a shape file. In the next step, annual forestry monitoring in the west of Gilan province, including the cities of Shaft, Foman, Soumesara, Bandar Anzali, Masal, Rezvanshahr, Talesh and Astara, was investigated in order to prepare afforestation maps and identify the reasons for the success and failure of the implemented plans.
The landscape approach
Multi-temporal data of Sentinel-2 satellite was used from the first half of March to December of 2016 for at least 6 periods with an interval of 30-40 days. After processing, interpreting and analyzing the data, these images were used to estimate the features of the land.
Each city is a landscape unit, based on which two land surface parameters, i.e. tree cover index and NDVI index, were estimated.
Discussion and Results:
The highest percentage of afforestation is related to the city of Astara, followed by Soemasera, and the lowest percentage is related to Foman.
Table 3- The amount of afforestation and urban and forest parks separately for each city in percentage
City Afforested area (hectares) Total afforested (present)
Shaft 911.7 4.78
Fooman 205.1 1
Somesara 4618.5 21
Bandar Anzali 885.3 4
Masal 1214.6 5.7
Rezvanshahr 4473.8 20
Talesh 2674.4 12
Astara 6345.4 30

Figure 3 shows the final results of the level and distribution of afforestation in the western cities of Gilan province using landscape metrics.



Figure 3- Map of forest afforestation and forest parks by each city

As the results of Figure 4 show, in determining the level with the landscape approach, the area of afforestation in all the study areas was more than the previous method, and the biggest difference between the two methods was in the cities of Razvanshahr and Soumesara.


Figure 4- Determining of afforestation in the study area with the landscape approach

Conclusion:
In the west of Gilan province, Rezvanshahr city has the highest and Foman city has the lowest afforestation level per capita, and climate and soil are known as the most important factors of this difference.
The extent of afforestation was obtained by using satellite images and land surface criteria from the ground data collection method, the main reason of which is the lack of accurate separation of forest cover from afforested cover, even despite the corrections before analysis; Each of the two methods used in this research has its advantages and disadvantages. In the land surface measurement method, despite the great ease, the cost and manpower and the time required are low, but if it is not combined with the ground data, it has a lot of error. In the method of land data and geographic information system, although the level of afforestation is determined with higher reliability and accuracy, it requires manpower, days and even months, time and cost are high. Therefore, the combination of these two methods to determine the area of afforestation is suggested according to the purpose and time and cost of each research.