سال انتشار: ۱۳۸۴

محل انتشار: اولین کارگاه مشترک ایران و کره در مدلسازی اقلیم

تعداد صفحات: ۱۵

نویسنده(ها):

Saeed Bazgeer – Agrometeorolcgical Division of l.R.of Iran Meteorological Organization

چکیده:

The temporal changes (1984 to 2002) in land use/land cover and their impacts on trend of meteorological parameters viz. maximum (Tmax) and minimum (Tmin) temperatures, rainfall (R) and potential evapotranspiration (PET) were studied using aerial photographs of 1984 and multi-date satellite data of 2002/2003 for Balachaur watershed in Nawanshahar district of Punjab state, India.Arc GIS package has been used for the land uselland cover changes analysis. The results showed that the area under crop land (923.8 ha), moderately dense forest (1575.5 ha), degraded forest (1007.8 ha), degraded land in hills and piedmont plain (861.5 ha), barren land along choes (seasonal rivulets) (526.7 ha) has decreased whereas, area under settlements (1041.1 ha), dense forest (2538.8 ha), plantations (678.3 ha), industrial use (l04.2 ha), ponds (18.4 ha), seasonal rivulets (302.2 ha) and brick kilns (213.3 ha) has increased over the span of 19 years. It revealed that three of the top five categories of land use/land cover changes were due to afforestation, as moderately dense forest converted into dense forest (1956.7 ha) and degraded forest converted into dense forest (976.5 ha) as well as moderately dense forest (755.5 ha). Moreover,there was a relatively significant improvement in the area under plantations which increased from 725.8 ha in 1984 to 1401.1 ha in 2002.Inspitc of increasing vegetative cover in the area, Tmax (0. SOC) has increased whereas, r.. (-0.6°C), R (13.7cm) and PET (-6.4 em) have shown a decreasing trend in recent years which did not find agreement with the results of previous studies. The results indicated that land use/land cover changes over time is not the single factor which causes variation on meteorological parameters.There might be other unknown factors which effect climatic variability in a region, such as CO2 concentrations and its effect on green house gases, atmospheric pollution and spectral distribution of the incoming solar radiation.
Therefore, it seemed to conclude that albedo change due to land use/land cover alterations together with other atmospheric factors and their intractions might be responsible for climatic variability in micro-level scale in the study area.