Korelasi arsitektur pohon model rauh dari Rasamala (Altingia excelsa Noronha.) dan model arsitektur roux dari jenis kopi (Coffea arabica L.) terhadap konservasi tanah dan air di area PHBM RPH gambung KPH Bandung Selatan

Abstract

Some factors influencing the occurrence of erosion including rainfall, soil type ground cover, and slope. Rainfall associated with translocation of water to the soil surface, that includes surface runoff, infiltration, stemflow and throughfall. Translocation of water was influenced by tree architecture model. This study was aimed to assess the level of erosion that occurred at CBFM area, forest and opened land related to soil and water conservation based on tree architecture model. The experiment was conducted from August 2010 to January 2011. Vegetation analysis at CBFM area and forest used a quadrate method, and line intercept used at opened land. Measurement of rainfall, throughfall, stemflow and runoff were conducted each rainfall. The results showed that throughfall of rasamala at CBFM areas is smaller (966.08 mm) than rasamala at forest area (976.80mm). Stemflow at CBFM area are 1146.47 mm and 1.35 mm at the forest area. The number of surface runoff at opened land is highest than CBFM areas and forests, it is 9611.42 liters. At opened land, the amount of soil erosion is highest 55.998 tons/ha/yr than CBFM area (1.53 tons/ha/yr) and forest (4.08 tons/ha/yr). Principle component analisys results showed that runoff is the most affected variable to the amount of soil erosion at PHBM area. The number of stemflow had a high effect to the soil erosion at the forest. While at open land, the most influential factor of soil erosion was run off.

Program pengelolaan hutan bersama masyarakat diharapkan dapat mengurangi terjadinya penurunan fungsi hutan, dengan demikian kerusakan hutan yang mengakibatkan terjadinya bencana alam seperti erosi dan longsor dapat dihindari. Erosi merupakan indikator dari konservasi tanah. Konservasi tanah berhubungan dengan konservasi air. Beberapa faktor yang mempengaruhi terjadinya erosi yaitu curah hujan, jenis tanah dan tumbuhan penutup tanah, serta kemiringan lereng. Curah hujan berkaitan dengan proses sampainya air hujan ke permukaan tanah yang meliputi laju aliran permukaan, infiltrasi, laju aliran batang dan curahan tajuk. Laju aliran permukaan, infiltrasi, laju aliran batang dan curahan tajuk dipengaruhi oleh model arsitektur tanaman. Setiap spesies tumbuhan mempunyai jenis arsitektur pohon yang khas.