تحلیل ژئوآنتروپوژنیک پوشش گیاهی ارتفاعات تالش، جلگه ها و دشت های پیرامون (مقاله علمی وزارت علوم)
درجه علمی: نشریه علمی (وزارت علوم)
آرشیو
چکیده
پوشش گیاهی و نحوه توزیع، انتشار و پراکنش آن در عرصه های جغرافیایی و نسبتی که با فعالیت های آنتروپوژنیک دارند . پوشش گیاهی و الگوهای فضایی و زمانی آن و روابط و نسبتی که با مؤلفه های فضای جغرافیایی و فعالیت های آنتروپوژنیک وجود دارد در ارتفاعات تالش و جلگه ها و اراضی پیرامون مورد بررسی قرار گرفت. بدین منظور از محصول مربوط به شاخص پوشش گیاهی NDVI ماهواره های ترا و آکوا به نام MOD13Q1 و MYD13Q1 در بازه زمانی 2003 تا 2020 با قدرت تفکیک زمانی 16 روزه استفاده شد . تصاویر ماهواره های ترا و آکوا با اپراتور میانگین ترکیب شد و به فرمت.asc تبدیل گردید. پروسه آماده سازی و تنظیم تصاویر با زبان برنامه نویسی پایتون انجام شد.. هسته تحلیل در پژوهش حاضر مربوط به تحلیل توزیع جغرافیایی، حریم و تغییرات زمانی است. در بخش توزیع جغرافیایی، الگوهای توزیع ژئوبوتانیک دنبال شد در بخش آنالیز حریم، الگوهای حریم 30، 7 و 2 کیلومتری عوارض و مراکز شهری، روستایی و زهکش های هیدرولوژیک اصلی دنبال گردید و در بخش تحلیل تغییرات زمانی، مدل مجموع قدر مطلق تغییرات یا انحرافات پوشش گیاهی به نام SAD پیکربندی و پیشنهاد شد و نتایج آن مورد تحلیل و بررسی قرار گرفت. در بخش تحلیل های ژئوبوتانیک، مؤلفه های ارتفاع، شیب، جهت شیب، تحدب سطح زمین فاصله از زهکش های اصلی مورد بررسی قرار گرفت. در نهایت دو مفهوم افت آنتروپوژنیک و ژئوبوتانیک پوشش گیاهی منطقه موردمطالعه تبیین و تحلیل شد و مقادیر آن به ترتیب معادل 2/0 و 4/0 برآورد گردید.Geoanthropogenic Analysis of the Vegetation cover in the Talesh Mountain and surrounding plains
IntroductionThe importance of vegetation, especially forests in mountainous areas, can’t be ignored. Forests and other plants provide a suitable environment for many other animal and plant species and increase the production capacity of ecosystems. Vegetation affects regional micro-climatic components regionally and locally and also controls soil erosion. The economy of local communities and the millions of people living on the edge of mountainous areas depend on the forests and plants that have grown and developed in those areas. It is worth mentioning that vegetation effectively protects the people living in these areas against environmental hazards such as rockslides, landslides, landslides, floods, etc. Therefore, the distribution and growth pattern of vegetation, taking into account the effective factors in these areas, is of particular importance. Elevation, direction and slope of the ground are three important and influential topographic factors in the distribution and pattern of establishment and expansion of vegetation in mountainous areas, which directly affects the vegetation. Among these three factors, height plays a very important role. Because as a factor controlling rainfall and temperature, it directly and indirectly affects the vegetation of mountainous areas and adjacent lands. Elevation, along with the slope direction and slope of the topographic surfaces of the earth, determines and controls the microclimate, and microclimate fluctuations will affect the spatial distribution and growth patterns of vegetation. One of the effective tools in studying the spatial distribution of vegetation is technology and remote sensing tools. This science is commonly used in large-scale and global assessments of vegetation and its fluctuations and geographical distribution. In this research, the researcher in the first step with a geo-botanical approach, has studied the horizontal and vertical patterns of distribution, distribution and distribution of vegetation in the Talesh mountainous unit and near lands. In the second step, the effect and relationship of anthropogenic activities with the results of the first part are compared and analyzed.Methodology At first, the study background, the required spatial database was prepared and adjusted. Spatial database setup was performed in two axes including vector database and raster database. In the vector data section, urban and rural areas, layers and geographical features related to human activities were adjusted for use in the two sections of cartography and analysis. Raster data includes digital elevation model (DEM) and satellite imagery. The study used digital altitude data published by the Japan Space Agency in May and October 2015 with a horizontal resolution of about 23 meters. This data taken from ALOS satellite images.Topographic position index, slope and slope direction were derived from digital elevation model. The product related to the NDVI vegetation index of Terra and Aqua satellites called MOD13Q1 and MYD1 3Q1 was used in the period 2003 to 2020 with a resolution of 16 days. The above data was downloaded separately from the NASA site for each of the Terra and Aqua satellites in (hdf) format. A total of 820 images from the study area, which belonged to the MODI images of the Terra and Aqua satellites, were downloaded and adjusted in (tiff) format. In the next step, the images of Terra and Aqua satellites were combined with the average operator and converted to (.asc) format. The entire image preparation and editing process was performed using the Python. After preparing vegetation data, topographic and hydrological data and human activity data, geobotanic and geoanthropologenic analysis of vegetation was followed in the context of analysis of geographical distribution, buffer analysis and temporal changes of vegetation.Results and Discussion Discuss Vegetation analysis was performed in two main axes of geobotany and geoanthropogenic at Talesh heights and plains and surrounding lands in different long-term, annual, seasonal and monthly time periods. The core of the present study analyzes is related to geographical distribution, buffer analysis and time changes. The time periods studied in this research are focused on long-term (2003 to 2020), annual, seasonal and monthly. In the geographical distribution section, geobotanical distribution patterns were followed. In the buffer analysis section, buffer pattern 30, 7 and 2 km of tolls and urban, rural and main hydrological drainage centers were followed. Vegetation called SAD was configured and proposed and the results were analyzed. In all time periods, a significant difference was observed between the eastern and western slopes of Talesh due to the moisture supply of the Caspian Sea and the hot and humid weather that moves towards the eastern side of Talesh. In the lowlands compared to the mountains and slopes, the predominant decline in vegetation index has been caused by anthropogenic activities and human interventions and deforestation and conversion of forest lands into farms and fields. The monthly pattern indicates the minimum vegetation index in February because the deciduous vegetation in this section lacks greenery and due to the cold weather and the cessation of the growing season, the greenery concentration is at a minimum. The highest degree of greenery has been observed in June and July, which coincides with the peak of the growing season as well as cultivation of the Caspian plain.ConclusionThe distribution and distribution of vegetation in geographical areas and their relationship with anthropogenic activities is necessary and important in regulating the human relationship with the environment. In the geobotanical analysis section, the components of height, slope, aspect, convexity of the terrain surface and distance from the main drainage path were studied. Finally, the two concepts of anthropogenic and geobotanical vegetation decline in the study area were explained and analyzed and its values were estimated to be 0.2 and 0.4, respectively.
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