ISLAMABAD: Pakistan, which is constantly confronted with critical situations of environment degradation and food insecurity, would likely to have an effective mechanism to overcome the negative impacts of these lingering issues on ago-economy and environment related in order conduct comparative studies and devise future plans for survival.
“Through Dendrohydrology, we can have the data of centuries old water flow cycle and weather patterns of Pakistans northern areas water rivers, which would be helpful in devising a policy needed for a comprehensive study of environment and agriculture,” said Prof. Dr. Moinuddin Ahmed, Laboratory of Dendrochronology and Plant Ecology, Department of Botany, Federal Urdu University of Arts, Science and Technology (FUUAST), Karachi, while exclusively talking to the Technology Times.
He said that the water flow of the Upper Indus Basin (UIB) at Partab Bridge for 500 years has been evaluated with the help of tree rings. “As flow peaks in May-September, therefore, five months were chosen to collect the annual water flow cycle.
He disclosed that a three-year study was carried out using Dendrohydrology, a new technology, at the Laboratory of Dendrochronology and Plant Ecology of Pakistan Department of Botany, FUUAST, Karachi. This research was funded by Pak-US and Higher Education Commission of Pakistan and collaborated with Prof. Dr. Edward Cook from Lamont Doherty Earth Observatory Columbia University USA, Prof. Dr. Connie Wood House from Laboratory of Dendrochronology, University of Arizona USA, Dr. Jonathan Palmer from Gondwana Tree Ring Laboratory, New Zealand while from Pakistan Prof. Dr. Moinuddin Ahmed at FUUAST Karachi, were the principal investigators of this project.
Dr Moin mentioned that since the old data about climatic changes lacks accuracy in modern times, one of the best “tools” to provide this missing climatic data has been the use of tree-rings which is called the Science of Dendrochronology.
About the rising importance of this sector, he said that developed countries are now spending billions of dollars each year to obtain information about the climatic change, supporting professional staff, which are of great practical importance to their forestry, agriculture, hydrology, glaciology, earthquakes and climatological studies.
The Dendrochronology is based on the strong tendency of tree to grow in annual increments on the outer portion of the main stem. In regions and some trees where nature permit continuous growth, rings are often indistinct and may not be annual in nature.
“We found the most disturbing feature in the stream flow reconstruction during the prolonged period of 112 years low flow period from 1572 to 1683 where mean flow was 3377 m3/s which is 11 per cent below the mean of gauge data. The driest period was 1637-1663 where mean reconstructed flow was 3271 m3/s and the flow was 8.1 per cent below the average. This period, if repeats in future will cause reduced Pakistans capacity for irrigation and hydroelectric power generation provided by Tarbela Dam which is the most worrying feature if happens in future. Therefore, we need more dams,” explained Dr. Moin.
In all trees there may be false, missing or locally absent rings due to unusual growth conditions. Narrow or tiny rings can go undetected unless surface preparation is excellent and proper magnification is used to examine the rings. Therefore, simple counting of rings is not a reliable method of determining the tree date of ring.
Annual growth rings of particular tree species are subjected to tree ring dating, cross matching or cross dating, the procedure of matching ring-width variation and other structural characteristics with in a tree and among trees that have grown in a particular area. This allows the identification of the exact calendar year for the formation of each ring.