Ecological study on site selection for shifting cultivation by the Iban of Sarawak, Malaysia. A case study in the Mujong River area

Sota TANAKA, Mohd Effendi Bin WASLI, Logie SEMAN, Augustine JEE, Joseph Jawa KENDAWANG, Katsutoshi SAKURAI, Yoshinori MOROOKA
2007 Tropics  
Site selection methods for shifting cultivation of the Iban wer e studied at five longhouses in the Mujong River area of Sarawak, Malaysia with special reference to their knowledge of secondar y vegetation. Shifting cultivation practices in the area were more intense than reported in previous studies and were conducted with one-time cropping of upland rice followed by about a 2−10 year fallow period. In all, 42 sites of secondar y forests were selected for the vegetation sur vey. They were
more » ... vey. They were classified into 25 suitable sites and 17 unsuitable sites for shifting cultivation by landowners, based on their perception through knowledge of vegetation. Inter views of farmers were also conducted to discover and assess indicator plants from plants encountered during the vegetation sur vey. In the first stage of decisionmaking for site selection, old secondar y forests, especially with dif ficult access, were excluded. Secondly, the farmers took into consideration the composition and growth of secondar y vegetation and, to a lesser extent, other environmental factors. During the early fallow period, less than about three years, some species such as Lalang (Imperata cylindrica) and Kemunting (Melastoma polyanthum) dominated. The farmers perceived such sites as unsuitable for shifting cultivation. Left fallow for several years (more than three years), tree species replaced small plants, e.g., grasses, fer ns and shrubs, through vegetation succession. Farmers perceived the presence of many tree species as indicating fertile land, but some of them occurred more frequently or with higher density at unsuitable sites than at suitable sites. Nevertheless, tree size as measured by stem diameter at breast height was greater at suitable sites than at unsuitable sites, indicating that the farmers comprehensively grasp the growth condition of these plants for land fertility evaluation and site selection. Judging from the rice yield sur vey, the Iban farmers site selection was appropriate for achieving sufficient rice production for their subsistence.
doi:10.3759/tropics.16.357 fatcat:2epee4juanamlgyr67aeqdgzsi