Effects of Topography and Monsoon Rain on Vegetation Composition of Sandy Arid Areas of District Khairpur Mir’s

Present study was conducted to evaluate the effects of monsoon rains and topography on plant communities of desert ecosystem of District Khairpur. The study was conducted at three desert sites differing in topography i.e. Kotdiji sand dunes, Ubhan Shah flat dunes and Sorah inter dunes, designated as site A, B and C respectively using quadrate method. The data of plant communities were recorded twice in a year during study period i.e. pre-monsoon and post-monsoon seasons and compared. The 35 plant species formed five plant communities at three sites. At site A Aerva - Calligonum-Leptadenia, formed pre-monsoon community and Aerva - Leptadenia–Salvadora formed post monsoon community. At site B, Aerva-Calligonum-Leptadenia and AervaLeptadenia-Citrullus formed pre and post monsoon communities respectively. While at site C, Calotropis-Alhagi, were dominant at pre and post monsoon. L. pyrotechnica showed significant correlation with C. colosynthesis and S. oleoides.