نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه آبخیزداری، دانشکده مرتع و آبخیزداری، دانشگاه علوم کشاورزی و منابع طبیعی گرگان، گرگان ، ایران
2 گروه محیطزیست، پژوهشکده علوم محیطی ، دانشگاه شهیدبهشتی ، تهران، ایران
چکیده
سابقه و هدف: افزایش غلظت دی اکسیدکربن جو به عنوان اصلی ترین عامل تغییرات اقلیمی است که تخریب در زیست بوم های طبیعی و بروز مشکل های مختلف محیط زیستی مانند برهم خوردن تعاد ل چرخه آب، عناصر غذایی و کربن در طبیعت ر ا در پی داشته است. پوشش گیاهی سطح زمین نقش اساسی در تثبیت کربن دارد که به شدت تحت تأثیر اقدام های مدیریتی بشر قرار گرفته و در طول زمان به تدریج تخریب یافته و مشکل های زیادی را در رفتار حوضه های آبخیز به وجود آورده است. بنابراین در سراسر دنیا اصلاح و احیای حوضه های آبخیز از طریق اجرای اقدام های متنوع مکانیکی و بیولوژیکی مدنظر سیاست گذاران، مدیران وکارشناسان قرار گرفته است. از جمله این اقدام ها می توان به انجام پروژه های آبخیزداری متنوع (نهال کاری، علوفه کاری و تراس بندی)با مشارکت صاحبان منافع به منظور بهبود شرایط در زیرحوضه ده چناشک از حوضه آبخیز چهل چای استان گلستان که یکی از آبخیزهای بحرانی استان بشمار می رود، اشاره کرد. بنابراین پژوهش حاضر به منظور سنجش اثرهای پوشش زمین ها و اقدام های گوناگون مدیریتی بر میزان ذخیره کربن خاک و همچنین بررسی دیدگاه بهره برداران درباره بهبود وضعیت آبخیز به صورت مقایسه ای در دو زیرحوضه ده چناشک (تیمار ) و چمانی بالا (شاهد) صورت گرفت .
مواد و رو ش ها: در پژوهش حاضر، اثر اقدام ها ی مدیریتی بر میزان ترسیب کربن در مکان های تحت اقدام های مدیریتی (تیمار) و انواع مختلف پوشش زمینها (جنگلی، زراعت و باغی) بررسی شده است. زمین های زراعی و باغی به عنوان شاهد و فعالیت های تراس بندی با کشت محصول های زراعی و باغی از نظر ترسیب کربن مقایسه شدند. همچنین اثر اقدام های مدیریتی بر بهبود پوشش گیاهی و کاهش فرسایش خاک از دیدگاه آبخیزنشینا ن و با استفاده از ر و ش پرسشنامه ارزیابی گردید . نمونه برداری به صورت تصادفی - سیستماتیک انجام شد . در امتداد هر ترانسکت به طو ر تصادفی سه پلات انداخته شد . در هر پلات، زیتود ه بالای سط ح زمین ، شامل اندام هوایی گیاهان زراعی و درختان محاسبه گردید .
نتایج و بحث: نتایج نشان داد میانگین ترسیب کربن زیتوده (تن در هکتار) در دو زیرحوضه تیمار و شاهد به ترتیب در جنگل های متراکم
( 10 / 5 و 91 / 4)، کم تراکم ( 98 / 4 و 80 / 4) و تخریب یافته ( 27 / 4 و 95 / 3) بیشتر از باغ های گردو ( 08 / 3 و 85 / 2) و سیب ( 21 / 2 و 00 / 2) و زمین های زراعی کشت شده با یونجه ( 55 / 1 و 50 / 1)، گندم ( 40 / 1 و 32 /1 ) عدس ( 38 / 1 و 30 / 1) و جو ( 26 / 1 و 19 /1 ) می باشد. در مورد اقدام های آبخیزداری اجرا شده در زیرحوضه تیمار، میانگین ترسیب کربن (تن در هکتار) در باغ های احداثی گردو ( 72 / 2) بیشتر از باغ های گلابی ( 88 / 1 ) و گیلاس ( 66 / 1) و زمین های تراس بندی شده با کشت یونجه ( 65 / 1)، گندم ( 50 /1) و عدس (40 /1) می باشد. همچنین مقایسه آماری با استفاده از آزمون T در بین جنگل های متراکم، کم تراکم و زمین های تخریب یافته و باغ های سیب و زمین های زراعی کشت شده با جو، از نظر ترسیب کربن اختلاف معنی داری را نشان نداد ( p=0.05 ). در مورد مقایسه باغ های احداثی گردو، گلابی و گیلاس و زمین های تراس بندی شده با عدس، یونجه و گندم در مقایسه با زمین های شاهد از نظر مقدار ترسیب کربن تفاوت معناداری به دست آمد ( p=0.05 ). از طرف دیگر، ارزیابی دیدگاه آبخیزنشینان در مورد اثر اقدام های مدیریتی اجرا شده بیانگر نقش بسزای آنها در بهبود شرایط منطقه از نظر پوشش گیاهی، تثبیت خاک و کاهش فرسایش است.
نتیجه گیری: از بین اقدام های آبخیزداری انجام شده، توسعه باغ ها بویژه باغ های گردو در زمین های زراعی شیبدار به دلیل قابلیت بالاتر در جذب و نگهداشت کربن و جلوگیری از فرسایش خاک به عنوان یکی از گزینه های مدیریتی با اولویت بالا برای اجرا در منطقه پیشنهاد می گردد .
کلیدواژه‌ها
عنوان مقاله [English]
Evaluation of watershed management interventions on biomass carbon sequestration and stakeholders’ perception about watershed condition improvement (case study: Dehchenashk sub-watershed, Chehl Chai watershed)
نویسندگان [English]
- Zeinab Karimi 1
- Vahedberdi Sheikh 1
- Amir Sadoddin 1
- Naghmeh Mobarghaee Dinan 2
1 Department of Watershed Management, Faculty of Rangeland and Watershed Management, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran
2 Department of environment, Environmental Science Research Institute, Shahid Beheshti University, Tehran, Iran
چکیده [English]
Introduction: Increasing the atmospheric carbon dioxide concentration is a major cause of climate change that has led to degradation in natural ecosystems and incidence of various environmental problems such as imbalances in hydrologic, nutrients, and carbon cycles in nature. Land surface cover, which has an important role in carbon sequestration, has been strongly influenced by human activities and gradually degraded over time and created a number of challenges in the behavior of watersheds. Therefore, worldwide rehabilitation and restoration of watersheds through the implementation of a variety of mechanical and biological measures have been considered by policymakers, managers, and technical experts. For instance, various watershed management projects (tree sapling, permanent forage cultivation, and terracing) have been implemented with the participation of stakeholders to improve conditions in the Dehchenashk sub-watershed of the Chehl-Chai watershed, where is considered as the most critically degraded watershed of the Golestan Province, northeastern Iran. Therefore, this research was carried out to evaluate the effects of land cover and various management measures on the amount of carbon sequestration in surface soil layer through a comparative analysis between two sub-watersheds of Dehchenashk (treatment) and Chamanie-bala (control).
Material and methods: In the present study, the effect of management measures on carbon sequestration in areas under management measures (treatment) and types of land use (forest, croplands, and orchards) was studied. The croplands and orchards as controls and terracing and tree saplings activities (biological measures) as the treatment measures were compared in terms of carbon sequestration. Sampling was conducted using randomly selected plots along the defined transects. Within each plot, above-ground biomass was measured for crops and trees. Also, the effect of management measures on improving land cover and reducing soil erosion from viewpoints of the local stakeholders was carried out using the questionnaire survey.
Results and discussion: The results showed that the average of biomass carbon sequestration (ton/ha) in both treatment and control sub-watersheds in dense (5.10 and 4.91), low-density (4.98 and 4.80), and degraded forests (4.27, 95 and 95) was more than walnut (Juglans regia) (3.08 and 2.85) and apple (Malus pumila) (2.21 and 2.00) orchards, and croplands cultivated with alfalfa (Medicago sativa) (1.55 and 1.50), wheat (Triticum aestivum) (1.40 and 1.32), lentil (Lens culinaris) (1.38 and 1.30), and barley (Hordeum vulgare) (1.26 and 1.19), respectively. Regarding biological practices carried out in the treatment sub-watershed, the average carbon sequestration in walnut orchards (2.72) was higher than pear (Pyrus communis) (1.88) and cherry (Cerasus avium) (1.66) orchards and terraced lands cultivated with alfalfa (1.65), wheat (1.50) and lentil (1.40). Also, statistical comparison using T-test between high density, low-density, and degraded forests and apple orchards and barley croplands showed no statistically significant difference at 5% level. The amount of sequestrated biomass carbon in walnut, pear, and cherry orchards and terraced lands cultivated with lentil, alfalfa, and wheat showed significant differences in comparison with the control lands. Moreover, the evaluation of viewpoints of the local stakeholders on the effect of management measures implemented in the Deh-Chanashk sub-watershed, indicated that they believe that the implemented watershed management practices have played a significant role in improving the sub-watershed condition in terms of land cover, soil stabilization, and soil erosion reduction.
Conclusion: Therefore, among the watershed management measures undertaken, extending the orchard plantation, particularly walnut plantation, to croplands on the steep slopes is recommended as a high priority management option across the study region due to higher ability to carbon sequestration as well as soil erosion prevention.
کلیدواژه‌ها [English]
- Watershed management
- Carbon sequestration
- Soil erosion
- Stakeholders’ viewpoint
- Chehel-Chai watershed
Agharazi, H., 2017. Biomechanical operation effect on soil carbon of Pakal Basin, Markazi Province. Watershed Engineering and Management. 10 (4), 529-536. (In Persian with English abstract).
Allison, L.E., 1965. Organic carbon. In: Black, C.A., Evans, D.D., White, J.L., Ensminger, L.E., Clark, F.E. (Eds.), Methods of Soil Analysis, Part 2, Chemical and Microbiological Properties. American Society of Agronomy, Madison, 1367.
Amirnejad, H., 2004. Determining total economic value of the forest ecosystem of northern Iran with emphasis on environmental-ecological valuation and conservation values. PhD Thesis, Faculty of Agriculture, Tarbiat Modares University, Iran.
Anonymous., 2005. Manual of biomass survey and analysis. Forestry Research and Development Agency and Japan International cooperation Agency, 23 p.
Basuki, T.M., Van Laake, P.E., Skidmore, A.K., and Hussin. Y.A., 2009. Allometric equations for estimation the above-ground biomass in tropical lowland Dipterocarp forests. Forest Ecology and Management, 257, 1684-1694.
Cannell, G.R., 2003. Carbon sequestration and biomass energy offset theoretical, potential and achievable capacities globally in Europe and UK. Biomass and Bioenergy, 24, 97-116.
Falahatkar, S., Hosseini, S.M., Ayoubi, S. and Salman Mahiny, A., 2013. The impact of primary terrain attributes and land cover/use on soil organic carbon density in a region of northern Iran. Journal of Water and Soil, 27 (5), 963-972. (In Persian with English abstract).
FAO, 2002. Agriculture in the world, towards 2030-2015. (Translated by Hooman Fathi). Publications of Research Planning and Agricultural Economics Research Institute, Ministry of Jihad Agriculture 191 p.
Farzi, H., Tamartash, R., Jafarian, Z. and Tatian, M.R., 2019. Effects of Watershed Management Measures on Functional Diversity Indices and Soil Carbon Sequestration (case Study: Arangeh Watershed, Alborz Province). 14th National Conference on Watershed Management Science and Engineering of Iran, 16th-17th July, Urmia, Iran.
Forozeh, M.R., Heshmati, G.A., Ghanbarian, G.A. and Mesbah, S.H., 2008. Comparison of carbon sequestration capacity of three plant species of sunflower, black guinea and plain artichoke In the dry rangelands of Iran (case study: Garbayegan plain of Fasa). Journal of Environmental Science. 34 (46), 65-72.
Hargreaves, K.J., Milne, R. and Cannell, M., 2003. Carbon balances of afforested peatland in Scotland. Journal of forestry. 76 (3), 299-318.
Husch, B., Beers, T.W. and Kershaw, J.A., 2003. Forest Mensuration. 4th Edition, John Wiley and Sons Inc., 443 p.
INDUFOR, 2002. Assessing Forest Based carbon sinks in the Kyoto protocol Forest Management and Carbon sequestration. Discussion paper, 115p.
Karimi, Z. and Sheikh, V.B., 2019. Evaluation of the attitude stakeholders’ of natural resources and environment projects (case Study: Hablehroud Watershed). Journal of Watershed Engineering and Management. 11(2), 477-467. (In Persian with English abstract).
Komiyama, A., Ong, J.E. and Poungparn, S., 2008. Allometry, biomass, and productivity of mangrove forests: A review. Aquatic Botany. 89(2), 128–137.
Lal, R., 2003. Global potential of soil carbon sequestration to mitigate the greenhouse effect. Critical Review in Plant Sciences. 22 (2), 151-184.
Lal, R., 2008: Carbon sequestration in soil. Forest Ecology and Management. 3, 20.
MacDicken, K.G., 1977. Aguide to Monitoring Carbon Storage in Foresty and Agroforesty Projects. Winrock International for Agricultral Development, Forest Carbon Monitoring Program.
Meshesha, Y.B. and Birhanu, B.S., 2015. Assessment of the effectiveness of watershed management intervention in Chena Woreda, Kaffa Zone, Southwestern Ethiopia. Journal of Water Resource and Protection. 7, 1257-1269.
Moradi Shahgharie. M. and Tahmasebi. P., 2015. Investigation of exclosure effect on carbon sequestration and physical and chemical properties of soil in semi-steppe rangelands of Chaharmahal and Bakhtiari province. Journal of Natural Ecosystems Iran. 6(4), 109-97. (In Persian with English abstract).
Motamed vaziri., B., Mirzaei, M.A., Sharifi, F. and Mohebi. A., 2011. The effect of the implementation of watershed management projects on vegetation changes and sustain mass movements. Journal of Remote Sensing and GIS planning Journal. 2, 3. (In Persian with English abstract).
Nadimi, N., Zahtabian, G. and Malekian, A., 2012. Evaluation of the role of watershed management biological measures On flood reduction. (case study: Yangje Watershed). Watershed Research (Research and Construction). 96, 97-107.
Pahlavan Yali, Z., Zarrin Kafsh, M. and Moeini, A., 2016. Quantitative estimation of soil carbon sequestration in three land uses types (Orchard, Paddy, Rice and Forest) in a part of Ramsar lands, northern Iran. Journal of Water and Soil. 30(3), 758-768. (In Persian with English abstract).
Parsapour, M.K., Sohrabi, H., Soltani, A. and Iranmanesh, Y., 2013. Allometric equations for estimating biomass in four poplar species at Charmahal and Bakhtiari province. Iranian Journal of Forest and Poplar Research. 21(3), 528-517. (In Persian with English abstract).
Post, W.M. and Kwon, K.C., 2000. Soil carbon sequestration and land-use change, processes and potential. Global Change Biolog. 6(3), 317-327.
Rahbar, G.H., Sadat Azimi, M. and Behnoudi, S., 2016. Evaluation the efficiency of terracing practices on carbon sequestration for climate changes mitigation. 5th Conferences Rainwater Catchment System, 24th and 25th February, Gilan- Rasht, Iran. (In Persian with English abstract).
Rousta, M.J., Enayati, K., Soleimanpour, S.M. and Mesbah, S.H., 2019. The environmental value of stored carbon in the soil of floodwater spreading fields of Gareh-Bygon Plain, Fasa, Iran. Watershed Management Research. 32(1), 31-41. (In Persian with English abstract).
Sabin, F.F., 1996. Remote Sensing. Principal and Interpretation 3rd Ed., W.H.Freman and company, New York, USA. p. 494.
Sadeghi, S.H.R., Forootan, F. and Sharifi, F., 2004. Watershed Management actions the performance evaluation of qualitative method (case study: Catchment kan). Geographical Research Quarterly. 79, 38-47. (In Persian with English abstract).
Schuman, G.E., Janzen, H. and Herrick, J.E., 2002. Soil carbon information and potential carbon sequestration by rangelands. Environmental Pollution. 116, 391-396.
Sreedevi, T.S., Wani, R., Sudi, M., Patel, T., Jayesh, S. and Singh, S., 2006. On-site and off-site impact of watershed development: A case study of Rajasamadhiyala, Gujarat, India. Global Theme on Agro-ecosystems Report no. 20, Patancheru 502 324, Andhra Pradesh, India: International Crops Research Institute for the Semi-Arid Tropics, 1-44.
Shahidipour, A., 2011. Investigation of the relationship between the emission of pollutants gases, energy consumption and value added in Irans economic sectors with emphasis on the intensity of pollution, M.Sc. Thesis, Faculty of Natural Resources, University of Tehran, Iran.
Shahrokh, S., Souri, M., Moetamedi, J. and Eftekhari, A., 2017. Effects of contour furrow on soil and biomass carbon sequestration (case study: Khalifan Rangelands, Mahabad). Iranian Journal of Range and Desert Research. 24(1), 98-109. (In Persian with English abstract).
Subedi, B.P., Pandey, S.S., Pandey, A., Bahadur Rana, E., Bhattarai, S., Raj, Banskota, T., Charmakar, S. and Tamrakar, R., 2010. Asia Network for Sustainable agriculture and bio resources. Federation of Community Forest Users, Nepal, Internationalcenter for Integratedmountain Development, Norwegian Agency for Development Cooperation, Guidelines for Measuring Carbon Stocks in Community-managed Forests. p. 16.
Tahmors, M., Jafari, M., Ahmadi, H., Azarnivand, H. and Nazari Samani, A., 2018. Quantitative evaluation of the effect of watershed management activities on carbon sequestration and storage in climate change reduce (case study: Parroud watershed - Shahroud watershed tributary). Ecohydrology. 5(1), 161-172. (In Persian with English abstract).
Terefe, H., Argaw, M., Tamene, L. and Mekonnen, K., 2020. Sustainable land management interventions lead to carbon sequestration in plant biomass and soil in a mixed croplivestock system: the case of Geda watershed, central highlands of Ethiopia. Ecological Processes. 9(34), 1-12.
Toru, T. and Kibret, K., 2019. Carbon stock under major land use/land cover types of Hades sub‑watershed, eastern Ethiopia. Carbon Balance and Management. 14(7), 1-14.
Yang, Y., Chen, Y., Li, Zh. and Chen, Y., 2018. Land-use/cover conversion affects soil organic-carbon stocks: A case study along the main channel of the Tarim River, China. PLoS ONE 13(11), e0206903.
United States Geological Survey (USGS), 2003. Carbon sequestration. Available online at: http//www.USGS.gov/.
Zianis, D., Muukkonen, P., Mäkipää, R. and Mencuccini, M., 2005. Biomass and Stem Volume Equations for Tree Species in Europe. Silva Fennica. Monographs. 4, 52.
)