ارزیابی پایداری عملیات جنگلکاری مانگرو در سواحل استان سیستان و بلوچستان (مقاله علمی وزارت علوم)
درجه علمی: نشریه علمی (وزارت علوم)
آرشیو
چکیده
ارزیابی میزان پایداری و موفقیت جنگلکاری ها، استراتژی و راهنمای مناسبی را جهت مکان یابی صحیح عملیات های توسعه و احیای جنگل ها فراهم می کند. در این مطالعه وضعیت پایداری جنگلکاری های مانگرو در 7 رویشگاه سواحل استان سیستان و بلوچستان ایران در دوره زمانی 1374 تا 1390 ارزیابی شده است. فرایند ارزیابی از طریق بررسی کمّی شاخص های تغییرات سطح، تغییرات تراکم، رشد ارتفاعی و زادآوری جنگل به انجام رسید. در این خصوص از تفسیر چشمی تصاویر ماهواره ای و روش نمونه برداری تصادفی با قطعات نمونه 1 آری دایره ای شکل استفاده شد. مطابق این بررسی در بازه زمانی 16 ساله، 5 میلیون و 457 هزار اصله نهال حرا در سواحل استان کاشته است که عمدتا فاصله کشت آنها 3×3 متر بوده است. نتایج نشان داد 1170 هکتار عرصه از سواحل استان به جنگلکاری حرا اختصاص داده شد که این میزان در سال 1390 به 303/9 هکتار کاهش پیدا کرده است. همچنین مطابق این بررسی رویشگاه های پزم و تنگ در وضعیت ناپایداری خیلی زیاد، رویشگاه های تیس و گالک در وضعیت ناپایداری زیاد، رویشگاه های ناصرآباد و بیردف در وضعیت گرایش به ناپایداری و تنها رویشگاه راشدی در وضعیت پایداری بسیار بالا قرار دارد. بر اساس این مطالعه در مجموع میزان موفقیت جنگلکاری های انجام شده 25/9 درصد است. نتایج ارزیابی پایداری نشان داد به جز رویشگاه راشدی، همه خورهای جنگلکاری شده در وضعیت ناپایداری قرار دارند. مکان یابی نامناسب و وقوع طوفان گونو در سال 1386 دلیل اصلی عدم موفقیت 74/1 درصدی عملیات جنگلکاری در منطقه است.Evaluation of Sustainability in Mangroves Afforestation in Southern Coastal of Sistan-and Balouchestan Province
Assessing the level of sustainability and success of afforestation provides a suitable strategy and guide for accurately locating forest development and restoration operations. The sustainability in mangroves afforestation in the 7 habitats of Sistan-o-Balouchestan province, Iran, was assessed through quantitative indicators including area changes, density changes, height growth, and forest generation. Satellite image visual interpretation and random sampling method were employed for this study. Over a 16-year period, 5457000 mangrove seedlings were planted in the coastal areas, primarily spaced 3 × 3 meters apart. The results showed that 1170 hectares of coastal land in the province were initially allocated for mangrove afforestation, but by 2011, this area had decreased to 303.9 hectares. According to this research, the Pouzm and Tang sites are highly unstable, while the Tiss and Galak sites are also classified as high unstable. The Naserabad and Birdaf sites are categorized as unstable, whereas the Rashedi site stands out as highly stable. This study indicated a successful afforestation rate of 25.9 percent. Stability analysis indicated that except of Rashidi habitat, other afforestation habitats are not in a stabile state. The main reasons for the 74.1 percent failure of afforestation were poor site selection and Gono storm on 2007. Extended Abstract Introduction The monitoring and evaluation of changes in sustainability indicators reveals the direction of forestry practices, demonstrating the extent of deviation from or proximity to the ideal state of sustainable forestry. The monitoring and evaluation of these sustainability criteria and indicators will assist decision-makers, planners, and national policymakers in the forestry sector in making informed decisions to achieve sustainable forestry practices. Undoubtedly, the analysis of the sustainability conditions in mangrove afforestation areas determines the context and foundation for proper management of these areas, as well as the selection and prioritization of development and restoration plans for mangrove forests. Therefore, this study aimed to evaluate the sustainability of mangrove forested areas along the coasts of Sistān and Baluchistān province. The study's findings will assist the managers in making informed decisions with a greater emphasis on the protection of these areas.MethodologyThe analysis of the sustainability trend in planted mangrove habitats in Sistān and Baluchistān province was conducted through the following five steps:Identifying the characteristics of mangrove plantations in the province: For this purpose, the environmental characteristics of mangrove afforestation in the two sectors of development and reclamation along the coasts of the province were identified through an examination of the available information sources in the General Directorate of Natural Resources and Watershed Management of the province, as well as field visits.Selection of sustainability assessment criteria and indicators: During this step, sustainability assessment criteria were chosen to evaluate the status of forest stands. Two specific criteria, namely the extent of forest resources and the health and survival of the forest, were employed for this evaluation, as they are well-suited for assessing forestry areas. Various indicators were considered for these two criteria, including measurement of the surface changes, density changes, height growth, and forest regeneration.Measurement of sustainability indicators: In order to assess the levels and evaluate the status of forest level changes, visual interpretation of Google Earth satellite images from 2020 was employed. For each habitat, a total of 15 sample plots were randomly selected to examine the percentage changes in density, height growth, and reproduction of forest stands.Analysis of the sustainability trend of afforestation stands: The scoring method was employed to analyze the sustainability trend of afforestation stands. Based on the importance of each indicator in determining the sustainability of forestry stands, as well as the weighted score obtained from the decline in density, the level of habitats, height growth, and the reproduction rate, the stability score for each indicator was calculated by multiplying the score of each index based on the results of the examination of the sample pieces and the estimation of the level in the weighted score. By summing up the sustainability scores of all indicators, the total sustainability score for each habitat was derived. The description of habitat stability was then determined based on these stability scores.Results and discussionOn the coasts of Sistan and Baluchistan province, 7 estuaries in Chābahār and Kanārak cities, covering a total area of 1640 hectares, have been afforested. Out of this total area, 1170 hectares have been developed, while the remaining portion has been left vacant for the expansion of hand-planted forests. From 1995 to 2011, 5 million and 457 thousand mangrove saplings were planted on these beaches, with a planting distance predominantly set at 3x3 meters. The afforestation area of the Rashidi habitat is in the best state of stability, while the Pezam and Tang habitats are in the worst state of instability. Out of the 7 coastal habitats in Sistan and Baluchistan province, a total of 6 habitats are experiencing varying degrees of instability, ranging from instability to extreme instability. The primary reason for the significant decline in the forestry level was the impact of Gono storm in 2016 along the coasts of Sistān and Baluchistān province. One of the notable effects of this storm was the morphological changes observed in many estuaries within the province.ConclusionThe results of this study indicated that 85% of the afforested stands in Sistān and Baluchistān province are experiencing varying degrees of instability, ranging from instability to extreme instability. These findings highlight shortcomings in the selection of planting areas, the planting pattern, and the maintenance of the planted stands. Among these factors, the site selection of the areas stands out as the primary reason for the failure of mangrove afforestation along the coasts of this province.FundingThere is no funding support.Authors’ ContributioAuthors contributed equally to the conceptualization and writing of the article. All of the authors approved the content of the manuscript and agreed on all aspects of the work.Conflit of InterestAuthors declared no conflict of interest.AcknowledgmentWe are grateful to all the persons for scientific consulting in this paper.We are grateful to the experts of the Natural Resources and Watershed Management Department of Sistān and Baluchistān province.
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