This highway was connected to the west along the Bampur Valley, which drains into the marshy Jaz Murian Basin. The valley is located at the east end of the Jaz Murian Basin and the survey zone is some km from the basin. The valley, which is surrounded by the Karvandar Birk mountains in the north, and the Hamont and Ahouran mountains to the south, is very narrow in the vicinity of Damin about km wide Abdollah-Garoosi : 9. It gradually widens to about km to the west until it joins the Jaz Murian Basin.
The Bampur River, which originates in the Karvandar Mountains, flows southwards to Damin and Iranshahr, and finally westwards to Bampur and after km feeds into the basin itself Seyed Sajjadi : Cultivated regions are situated in the middle and upper reaches of the Bampur River, particularly around Iranshahr. Here, the river is absorbed into porous detrital deposits, and re-appears irregularly as springs and seepages lower down the valley in the direction of Bampur Fisher : When Stein visited the area, the Bampur River flowed from Iranshahr to Chah Hussaini in the west before being absorbed Stein : It is very notable that during the fresh surveys in July and June , the river was entirely dry Fig.
As qanats are frequently used to tap this water source, particularly as surface flow presents some curious and intractable features Fisher : ; it is more likely to assume that today the cultivated area around Iranshahr and Bampur mostly depend on the qanats rather than the river.
When Stein visited the Bampur Valley, he noted that the cultivated area extended without break from three km north of Iranshahr right up to Bampur and beyond. The width of the cultivated area along the right bank of the river gradually increases to a maximum of about 2. Beyond the fort, this area expands for another There is much evidence about different forms of water erosion during the quaternary period in the Iranian Plateau Mahmoodi : 7 in which the Bampur Valley is one of the most important evidence of water erosion in southeast Iran.
The width of the river and its alluvial bed with harsh gravel testify to the water erosion character, which repeated during time and finally replaced by the present drought period in the valley. Evidence of streams helps us to understand the possible reputations of the water erosions. It is notable to state that all the third millennium BC settlements discovered by Stein in Stein and Mortazavi in July Mortazavi : are probably evidence of the pluvial period in the Bampur Valley.
Therefore, it may be assumed that the emergence of the third millennium BC settlements in the Valley is a result of the availability and abundance of water resources and increase of the alluvial plains. The Iranian Plateau is located in the dry climatic area in which windy erosion and watery- windy erosions are dominant conditions Alijani : It has been argued that these conditions were also evidenced in the Plateau in antiquity Masoodian : Stabilized sandy dunes, rill erosions Koche and Kaloutak Yardang , which are the most important evidence of the above area Mahmoodi : 25 could lead us to this idea that the present is the key to the past Uniformitarianisum.
Our research team was able to discover the first two evidence in the Bampur Valley during the fresh survey of June Figs 3, 4 and 5. The above mentioned evidence was mostly observed around the third millennium BC settlements and the Bampur River. As the Bampur River could have been a gift for the Bampur People, drought of the river and the above mentioned evidence, which was a result of the proposed climate changes, may be considered as causes for the collapse of the civilization in the Valley.
All the above evidence shows us that in transitional climate area Fig. Lack of precipitation and dry climate are the most important characters of this area in which plants cover are poor and wind move aeolian sand. Due to reduction of wind speed Aeolian sand are deposited; consequently sand dune form Tricart : These dunes were the most significant problem in the surveys of and as they covered many parts of the ancient mounds Figs.
These dunes are usually destroyed during rainy climate by running water; dune sandy fossils are the most prevalent evidence of the above process in which drought periods are repeated Figs. We discovered several of these fossils during our surveys along the Bampur River and around the third millennium BC settlements in the Valley Fig. This evidence could testify that during the prehistoric time the people of the Bampur Valley experienced climate changes that influenced their life.
Streams flowing, which are minor branches of rivers, are stopped in small depressions and rarely join to sea in arid regions. These depressions, functioned as supply water in arid regions, are called Playa Chotte in Sahara Desert and Sebkha in Arab deserts Shahrabi : The playas, temporary lakes, which are regularly adjusted in these regions, provide availability of water sources for settlements around themselves.
It is notable to state that underground water sources also flow toward playas and increase the amount of water in these temporary lakes Fig. As these lakes are temporary, patoralism is completely depended on them Tricart : During our Surveys in and , we found one of these lakes that locally called Chil Tratok.
The name Chil Tratok consists of two parts, Chil, which means pond and Tratok, a kind of plant. The site, which has 2 m height and an elevation of m, is located 8 km to the west of Bampur, 1 km to the north of the Bampur River and on the side of the road from Bampur to Spakeh. As the third millennium BC settlements in the Bampur Valley were gradually disappeared from period IV onward, it is more reliable to believe that Chil-Tratok was a settlement for Nomad peoples.
After environmental crisis, which was a common event in Southeast Iran and probably in broader regions between Mediterranean and the Indus Ocean, these settlements are also collapsed during the first centuries of the second millennium BC Mortazavi : All through this paper methodological uniformitarianism provides the cornerstone for reconstructing the past and is necessary for achieving any measure of understanding of the processes and patterns of environmental changes in the Bampur Valley.
This approach, which firstly applied in the Iranian archaeology in this paper, tried to reconstruct the environmental changes in the Bampur Valley. As stated, a number of archaeological and geographical evidence, which were discovered during our surveys in and , testified to the environmental changes in this Valley.
The fragility of the Bampur Valley environment, which is located in the global transitional climatic area, has been the main factor for the environmental changes. Environmental evidence such as dune sandy fossils and playas discovered through the survey; and archaeological evidence discovered through the survey showed us that the third millennium BC settlements were closely depended to their fragile environment.
In fact, the population levels of this valley oscillated around the carrying capacity and fluctuations in population levels adjusted to the possible fluctuations in resources levels Mortazavi : Kirch believes that variations in the carrying capacity may result from a range of temporal processes, including environmental crisis, including periodic drought and cyclonic destruction of crops Kirch : It seems that constant environmental changes in the Bampur Valley did not allow to the third millennium BC settlements to have a stable pattern of population changes.
Instability of environment finally weakened these settlements and with decline of long-distance trade, these settlements also collapsed during the first centuries of the second millennium BC Mortazavi : The above-mentioned evidence, which indicates the climatic and environmental changes in the Valley, demonstrates the uniformitarian theory in the area.
Alijani, B. Climate of Iran. Abdollah-Garoosi, A. Historical Geography of the Bampur Area, Baluchestan. In Persian. Jahad-i-Daneshgahi Press, Tehran. Bell, M and M. C Walker. Late Quaternary environmental Change, Physical and Human perspectives. Birks, H. Quantitative palaeoenvironmental reconstructions from Holocene biological data.
In: Mackay, A. Global Change in the Holocene, pp. Testing the robustness of numerical methods used to analyse data and ensuring the interpretation is ecologically meaningful.
Telford, R. Quaternary Science Reviews Evaluation of transfer functions in spatially structured environments. The secret assumption of transfer functions: problems with spatial autocorrelation in evaluating model performance. All age-depth models are wrong: but how badly? Skip to main content. Coring on a frozen lake. Main content Richard Telford, John Birks, Gaute Velle, Anne Bjune There are two strands to our past climate research - palaeoecological reconstructions and developing robust numerical methods for palaeoecology Palaeoecological Research Knowledge of the full range of variability in the natural climate system is necessary to allow us to separate out human-induced climate changes.
Key papers Bjune, A. Numerical Methods for Palaeoecology Testing the robustness of numerical methods used to analyse data and ensuring the interpretation is ecologically meaningful. Key papers Telford, R. Newly extracted sediment core. Related persons. Climate Change. Palaeo botany. Pollen analysis. Popular Science Outreach and lectures. Alpine Plant Ecology.
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