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Cháy thường xảy ra dọc theo mép trên của núi rừng mưa trên núi. Kilimanjaro (Beck et al 1986; Blot 1999, Meyer 1890, Salehe 1997). Điều này đặc biệt đúng trong thời gian đặc biệt khô thường xuyên xuất hiện trong giai đoạn miền Nam dao động El Nino (ENSO). Như một hệ quả, ranh giới rừng đã được hạ thấp sâu sắc, và rừng đã được thay thế bằng heathland thống trị bởi Erica excelsa, E. trimera, và E. arborea (gai và Beck 2001), với một số cô lập các bản vá lỗi nhỏ của rừng còn lại trên. | 5 Effects of Fire on the Diversity of Geometrid Moths on Mt. Kilimanjaro Jan C. Axmacher Ludger Scheuermann Marion Schrumpf Herbert VM. Lyaruu Konrad Fiedler and Klaus Muller-Hohenstein INTRODUCTION Fires often occur along the upper margin of the montane rain forest on Mt. Kilimanjaro Beck et al. 1986 Blot 1999 Meyer 1890 Salehe 1997 . This is especially true for exceptionally dry periods which regularly appear during the El Nino southern oscillation ENSO phases. As a consequence the forest boundary has been profoundly lowered and the forest has been replaced by heathland dominated by Erica excelsa E. trimera and E. arborea Hemp and Beck 2001 with some small isolated patches of forest remaining above the current closed forest boundary. This change in the vegetation is accompanied by various changes in ecological conditions. The temperature drops more rapidly at nightfall outside the forest and the microclimate is drier within the open heath vegetation leading to the disappearance of many ferns and epiphytic plants outside the forest. The objective of our study was to explore how these fire-induced changes affect herbivorous insects along the upper forest margins and in forest remnants. We investigated changes in species composition and diversity of nocturnal geometrid moth communities along an altitudinal transect covering intact closed forests below 3000 m a mosaic of forest remnants and heathland at 3100 m and heathland vegetation at 3300 m. The sites at 3100 m therefore enable a direct comparison of geometrid moth communities in heathland and forest fragments whereas the lower and higher portions of the transect albeit the altitudinal differences between the sites provide comparison of community structure and diversity of geometrid moths between large closed forest and heathland habitats. Geometrids were selected for four reasons 1 They are one of the three most diverse families of Lepi-doptera. 2 They are taxonomically rather well known Scoble 1999 . 3 They .
