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Jati telah menjadi sebuah spesies penting di sektor kayu tropis kualitas (misalnya Pandey dan Brown, 2000), erosi tanah di bawah perkebunan jati telah menghasilkan beberapa perdebatan (misalnya Bell, 1973; Pandey dan Brown, 2000; Ramnarine, 2001) karena sejumlah penulis menganggap bahwa sistem ini menyediakan atas hidrologis manfaat yang terkait dengan hutan (Carle et al., 2009). Berdasarkan anggapan suku tinggi erosi di bawah perkebunan jati, di beberapa negara seperti Kosta Rika, perkebunan tersebut tidak secara hukum didirikan pada lereng curam dari 30%, sementara lereng dengan gradien curam (N30%) telah dianggap cukup untuk hutan perkebunan spesies lain atau bahkan lain tanaman abadi seperti pohon-pohon kopi atau buah. Hutan menutupi kontrol pengikisan tanah oleh melindungi permukaan tanah dari dampak titisan hujan dan mengurangi kecepatan air run-off dalam siklus hidrologis (Brauman et al., 2007; Durán dan Rodríguez, 2008; Evans, 2009). Reboisasi dapat melindungi dan bahkan mengembalikan tanah rusak dan fungsi mereka hidrologis dalam siklus air (misalnya Bruijnzeel, 1997, 2004; Brauman et al., 2007; Van Dijk dan Keenan, 2007), karena dianggap sebagai untuk meningkatkan infiltrasi, porositas dan kelulusan, mempengaruhi recharge airtanah, permukaan run-off dan erosi lahan (misalnya Bonell et al., 2010; Ilstedt et al., 2007; Peta, 1995). Namun, beberapa kegiatan kehutanan, terutama penggunaan mesin tertentu, ekstraksi kayu dan penciptaan jalan hutan, dapat menyebabkan penurunan tanah dan pemadatan dan karena itu meningkatkan erosi (misalnya Worrel dan Hampson, 1997; Ziegler et al., 2004a, 2004b).Faktor lain rendah tingkat produksi sampah juga telah dikaitkan dengan tingginya tingkat erosi di bawah perkebunan jati (Boley et al., 2009). Namun, karena kayu jati pohon berganti daun, sejumlah besar daun biomassa diendapkan setiap tahun. Bukti sampah produksi dan tanah penutup oleh jati residu.The large leaves of teak trees are associated with an increase in raindrop erosivity, as drops falling from teak vegetation will have several times greater kinetic energy than those falling from other species such as Pinus sp. (Calder, 2001). The high erosivity of these dropswas also observed by Calder (2001) during a storm in India, after a forest fire had destroyed most of the understory vegetation. The post-fire recovery of vegetation brought about a reduction in the erosive energy, as the multilayered understory vegetation serves to protect the soil from the kinetic energy of the raindrops, thus reducing rainfall erosivity (e.g. Brandt,1988). Hence, the mistaken assumption discussed above that the understory vegetation is suppressed in teak plantations, also has an important bearing on the question of raindrop erosivity. Although the large raindrops associated with large teak leaves are highly erosive, properly conserved multilayered understory vegetation (accompanied by a litter layer) would reduce erosivity.A number of studies have highlighted the drastic increase in erosion rates as a result of prescribed fires in forest plantations (Hamilton, 1991; Maeght et al., 2011; Tangtham, 1992), so the generalized belief that teak plantations are prone to high rates of soil erosion probably originated in certain specific plantations where prescription fires are a common management tool. Although prescription fires are common in some teak plantations (Bell, 1973; Maeght et al., 2011; Pandey and Brown, 2000), they are not so common in the plantations observed in Central America. The absence of recurrent fires in the plantations analyzed in the present case study would favor the presence of understory vegetation along with a well-developed litter layer (Fig. 2), which contributes to lowering soil erosion rates. Hence, plantation management would appear to be the main factor affecting soil erosion in teak forest plantations, rather than the teak itself. However, intensive weed control using herbicides is common in most of the productive teak plantations (Pandey and Brown, 2000), including those observed in Central America, and is considered another cause of soil remaining unprotected, thereby leading to erosion and diminishing the hydraulic properties of the soil (Boley et al., 2009; Bonell et al., 2010; Bruijnzeel, 2004; Fernández-Moya et al., 2013; van Dijk and Keenan, 2007). Both prescribed fires and herbicides result in weed and understory reduction, hence a reduction in organic matter (Balagopalan et al., 1992; Boley et al., 2009). This is considered a soil degradation process,which has been identified as a cause of the deterioration of soil hydraulic properties in teak plantations (Fernández-Moya et al., 2013; Mapa, 1995).
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