Keanekaragaman Diptera Dominan pada Kanopi Pohon di Lanskap Hutan Hujan Dataran Rendah, Provinsi Jambi

Abstract

Hutan hujan tropis dataran rendah di wilayah Jambi mengalami penurunan tutupan kanopi secara masif akibat alih fungsi lahan menjadi perkebunan monokultur. Konversi lahan menyebabkan penurunan kelimpahan dan kekayaan spesies serangga seperti semut, Hymenoptera parasitoid, dan kumbang. Sampai saat ini, laporan penelitian mengenai dampak konversi lahan terhadap kelimpahan dan kekayaan spesies Diptera di Sumatra, khususnya di Bukit Duabelas dan Hutan Harapan, Jambi masih terbatas. Penelitian ini bertujuan mengetahui dampak konversi hutan menjadi perkebunan karet dan perkebunan sawit, pengaruh musim, habitat riparian, dan lanskap terhadap kelimpahan dan kekayaan spesies Diptera kanopi, khususnya di Jambi. Pengambilan sampel dilakukan dengan teknik pengasapan di empat tipe penggunaan lahan (hutan alami, hutan karet, perkebunan karet, dan perkebunan sawit), dua musim (kemarau dan hujan), dua habitat (riparian dan nonriparian), dan dua lanskap (Bukit Duabelas dan Hutan Harapan). Jumlah Diptera kanopi yang diperoleh yaitu 42 333 individu dari 29 subfamili, 109 genus, dan 947 spesies. Penelitian ini menunjukkan bahwa konversi hutan menjadi perkebunan menurunkan kelimpahan dan kekayaan spesies Diptera kanopi. Kelimpahan Diptera kanopi terendah ditemukan di perkebunan sawit, sedangkan kekayaan spesies terendah ditemukan di perkebunan karet. Komposisi Diptera kanopi paling mirip yaitu di hutan alami dan hutan karet, sedangkan komposisi Diptera kanopi paling berbeda ditemukan di hutan alami dan perkebunan sawit. Musim hujan meningkatkan kelimpahan dan kekayaan spesies Diptera kanopi. Keberadaan habitat riparian meningkatkan kelimpahan Diptera kanopi, tetapi tidak memengaruhi kekayaan spesiesnya. Lanskap Bukit Duabelas memiliki kelimpahan dan kekayaan spesies Diptera kanopi yang lebih tinggi daripada Hutan Harapan.

The lowland tropical rainforests in Jambi have experienced a massive decline in canopy cover, a direct consequence of land conversion into monoculture plantations. This drastic change in land conversion reduced the abundance and species richness of canopy insects, including ants, butterflies, parasitoid wasps, and beetles. It is crucial to note that, to date, research has been limited on the abundance and species richness of Diptera in Sumatra, particularly in Bukit Duabelas and Harapan Rainforest, Jambi, specifically on land conversion. This research aims to determine the impact of forest conversion into rubber and oil palm plantations, the effect of seasons, riparian habitats, and landscapes on the abundance and species richness of canopy Diptera, especially in Jambi. Canopy Diptera samples were collected using fogging in four land-use systems (forest, jungle rubber, rubber plantation, and oil palm plantation), two seasons (dry and rainy), two habitats (riparian and nonriparian), and two landscapes (Bukit Duabelas and Harapan Rainforest). A total of 42 333 individuals were collected and identified to morphospecies level, belonging to 10 families, 29 subfamilies, 109 genera, and 947 species. The finding of this study indicates that the conversion of forests into plantations reduces the abundance and species richness of canopy Diptera. The lowest abundance of canopy Diptera was found in oil palm plantations, while the lowest species richness was in rubber plantations. Canopy Diptera in forests has a similar composition to those in jungle rubbers, while it was most different in oil palm plantations. The rainy season increases the abundance and the species richness of canopy Diptera. The riparian habitat increased the abundance of canopy Diptera but did not affect their species richness. The Bukit Duabelas landscape has a higher abundance and species richness of canopy Diptera than the Harapan Rainforest.