Pengaruh Kerapatan Vegetasi dan Sifat Fisik Tanah terhadap Laju Infiltrasi di Kawasan Jasinga Silviculture Teaching Industry (JSTI)

Abstract

Hutan Jasinga Silviculture Teaching Industry (JSTI) termasuk hutan penelitian dengan kondisi ekosistem yang belum banyak diketahui. Dibutuhkan penelitian pada ekosistem setempat terutama terkait vegetasi, tanah, dan siklus hidrologi. Tutupan lahan vegetasi di Hutan JSTI belum merata yang memengaruhi resapan air tanah (laju infiltrasi). Penelitian ini bertujuan mengidentifikasi komposisi vegetasi dan sifat fisik tanah yang memengaruhi laju infiltrasi. Plot ditentukan melalui teknik purposive sampling berdasarkan kerapatan vegetasi. Komposisi vegetasi diketahui berdasarkan indeks nilai penting (INP). Laju infiltrasi diukur menggunakan double-ring infiltrometer. Hasil penelitian menunjukkan bahwa komposisi vegetasi bervariasi sesuai dengan tingkat kerapatan tajuk. Struktur tanah berupa subangular blocky dengan tekstur liat, kadar bahan organik tergolong tinggi (>4%), bulk density tergolong sedang, porositas yang didominasi kategori porous, serta kadar air dan laju infiltrasi plot vegetasi rapat cenderung lebih besar dibandingkan plot vegetasi jarang. Parameter kerapatan vegetasi dan sifat fisik tanah yang dianalisis memiliki pengaruh yang kuat hingga sangat kuat dengan laju infiltrasi tanah.

The Jasinga Silviculture Teaching Industry (JSTI) forest is a research forest with ecosystem conditions that have yet to be widely known. Research on the local ecosystem is needed, especially regarding vegetation, soil, and the hydrological cycle. Vegetation land cover in the JSTI Forest is uneven, which affects groundwater absorption (infiltration rate). This study aims to identify the vegetation composition and soil physical properties that affect the infiltration rate. Plots were determined through a purposive sampling technique based on stand density. Vegetation composition is known based on the important value index (IVI). The infiltration rate was measured using a double-ring infiltrometer. The results showed that the composition of the vegetation varies according to the level of crown density. The soil structure is subangular blocky with a clay texture, the organic matter content is high (> 4%), the bulk density is moderate, the porous category dominates the porosity, the water content and infiltration rate of dense vegetation plots was more excellent than sparse vegetation plots. Vegetation density parameters and soil physical properties analyzed have a strong to very strong relations with soil infiltration rate.