گرده های فسیل دریاچه پریشان از دیدگاه آب و هواشناسی دیرینه

امروزه مطالعات آب و هواشناسی دیرینه به دلیل کاربرد در مسایلی چون بررسی تغییرات آب و هوایی گذشته کره زمین، باستان‌شناسی، درک میزان تاثیر انسان بر تغییرات زیست محیطی، بازسازی داده‌های آب و هوایی طولانی مدت، شبیه سازی محیط های دیرینه یکی از محبوب ترین زمینه های مطالعاتی شده است. از جمله روش های متداول در مطالعات آب و هواشناسی دیرینه روش گرده‌شناسی است و از جمله مهم ترین ابزار این روش، اطلس های گرده‌شناسی هستند. در ایران مطالعات آب و هواشناسی دیرینه و به تبع آن روش گرده‌شناسی سابقه چندانی ندارد و کمبودهای زیادی در این رشته وجود دارد. از جمله این کمبودها می توان به نبود اطلس گرده های گیاهی ایران اشاره کرد. با توجه به این مسئله در این مقاله سعی شده است با ارایه گرده‌های گیاهی حوضه آبریز دریاچه پریشان، بخشی از این خلاء پر شود. بدین منظور گرده گیاهان منطقه و مغزه دریاچه پریشان استخراج شد. برای جداسازی گرده های گیاهی از نمونه رسوبی از روش استاندارد استخراج گرده‌های گیاهی استفاده شد. استفاده شد. در نهایت با تهیه اسلاید و کدگذاری آنها، توسط میکروسکوپ نوری گرده ها، شناسایی و عکسبرداری شدند. در مجموع تعداد 28 گرده شناسایی شد که مشخصات و تصویر هر گرده ارایه شده است.

Fossil Pollen Grains of Lake Parishan from the Viewpoint of Paleoclimatology

Fossil Pollen Grains of Lake Parishan from the Viewpoint of Paleoclimatology Mahmoud Davoudi, Assistant Professor, Geography Department, Faculty of Literature and Human Science, Gilan University, Iran Ghasem Azizi...., Associate Professor, Natural Geography Department, Faculty of Geoghraphy, University of Tehran, Iran Valiollh Mozafariyan, Associate Professor, National Botanical Garden of Iran, Iran Davood Salmani, MSc., Faculty of Geography, University of Tehran, Iran Received: July 1, 2015 Accepted: December 8, 2015 Extended Abstract Introduction Nowadays, paleoclimatology studies are considered as one of the most popular study fields, for they can be applied for various subjects like the study of past climatic changes of the earth, archeology, the effects of human beings on environment, rebuilding of longterm climatic data and ecosystem simulation. Climate change on all aspects has serious impacts on natural and human life. Natural variability is an inherent feature of climate that happens in short time and long time As the Earth's climate and ecological conditions during the various geological changes and fluctuations very strong. Knowledge of weather and its patterns over long periods of time will help to determine the future climate. Thus, climate experts and environmental scientists have shown a lot of attention to paleoclimatology and ecology past changes. Through studies of paleoclimatology can reconstruct climate elements of past and predict the pattern of future climate. In fact, to predict the future climate the longterm data is needed while direct measurement instrument of meteorological data only able to provide a picture of the climate of the past few decades. Therefore, to surmount the direct measurement of poverty, paleoclimatologist must use indirect evidence to discover and reconstruct the long time data. Palynology is one of the most popular methods in metrological studies and palynology atlases are the most significant tools of this method. As a matter of fact, the annals of paleoclimatology studies and palynology studies in Iran is not so rich, leading to numerous shortages in the field like lack of pollen atlas of Iran. As a result, this study aims at filling this gap by introducing the plant pollens of Parishan Lake basin.Material and Methods Two field studies were done in April and June 2013 to conduct the present research. Searching on the basin of Parishan Lake, the vegetation sles were assembled, dried, and transferred to the Botanical National Park of Iran. Then, the sles were transferred to paleoclimatology laboratory of Geography Faculty in University of Tehran in which they sled the plants’ flowers. In the second step of sling, a core, measuring about 8.5 m, was taken from the floor of Parishan Lake and its pollens were investigated with intervals of 10 cm. Moore et al. (1991), Erdtman (1952), Faegri and Inversin (1975) methods were used to separate the pollens. Then, Silicon oil 2000 was added to avoid oxidization. Besides, they were put in furnaces with 500C for 24 hours to be dried. Making slides and codifying by microscope, the pollens were recognized and photographed. Official sites and authoritative books and articles were applied to identify the pollens of the core (Faegri and Iversen, 1975 Kremp, 1965 Punt et al., 1994 Hesse et al., 2009 Roubik, 2003 Demske, 2013 Vafadar et al., 2010 Binka, 2003 Behboodi, 2005 Palynology Websites of Australia, Arizona, and San Francisco). Moreover, 5 pollens of each type were measured and the average was considered as the normal size of the pollen.Results The findings reveal that there are 28 pollens in the basin of Parishan Lake including 4 tree pollens, oak, pistachios, almond and olive, 2 water plant pollens of Cyperaceae and Sparganium sp., while the rest are shrubs and herbaceous plants. Their features, including polar axis, equatorial axis, and forms, are presented in Table 1, while equatorial view, polar view, the walls and the level decorations are shown in Figures 2 10. Pollen size is not fixed and can be smaller or larger than the models listed. The size listed is the average number of groups of any kind.Conclusion As a matter of fact, lack of plant pollen atlas and fossil pollens of Iran has disturbed paleoclimatology studies based on palynology. In fact, the most significant advantage of identifying past climatic changes based on palynology is the recognition of much more pollens in the sediments. However, lacks of pollen articles and pollen atlases have affected this subject. As a result, this research aims to study the plant pollens of Parishan Lake basin which were assembled, prepared, recognized, and photographed by scientific methods. The final output revealed that there are 28 plant pollens including tree pollens, shrub pollens, herbaceous pollens and water plant pollens. Several photos of each pollen are presented to help the researchers to recognize the pollens. These photos were taken from different views like polar view, equator view, pollen wall, level decoration and size.