[ABSTRAK Sebagai upaya menahan dan mengurangi laju erosi pantai utara Provinsi Jawa Tengahtelah dilakukan pembangunanstruktur keras (APO dan permeable HE) di DesaTimbulsloko, Kabupaten Demak. Fungsi struktur APO dan struktur HE bersifatsementara untuk meredam gelombang datang dan memperangkap sedimen sampaiterbentuk lahan sedimentasi yang relatif stabil untuk ditanami mangrove ?metode softstructure-, yang secara jangka panjang pertumbuhan perakaran mangrove akanberfungsi alami memulihkan kembali stabilitas pantai.Penilitian ini mengulas mengenai pembentukan sedimen di sekitar struktur APO danstruktur permeable HE sampai dengan layak ditanami mangrove. Metode penelitianmenggunakan deskriptif eksploratif dan pemodelan. Pengambilan sampelmenggunakan purpose sampling method terhadap data hidro-oseanografi (pasangsurut, arus, gelombang), sedimen, dan perubahan garis pantai. Pengolahan datadilakukan sebagai parameter dan batasan dalam pemodelan lebih lanjut. Analisiskesesuaian sedimen juga dilakukan untuk melihat kelayakan melakukan rehabilitasimangrove.Hasil pengamatan hidro-oseanografi diperlukan sebagai masukan dalam analisasedimentasi. Pengamatan pada APO segmen-1 sedimen yang terkumpul selama 7bulan sebanyak 4.519 m3 atau 21,52 m3/hari dan segmen-2 sebanyak 4.836 m3 atau26.87 m3/hari. Sedangkan struktur permeadel HE 1-3 segmen selama 6 bulan(Desember 2013 ? Mei 2014) sebanyak 3849m3 atau 21,38 m3/hari. Hasil pemodelandengan program CEDAS simulasi 6 bulan menunjukkan sedimentasi sebesar 3550m3. Sedangkan jenis mangrove yang cocok ditanam dengan subtrat lumpur berpasiradalah Rhizopora mucronata dan Rhizopora stylosa.Sedimentasi yang terbentuk menunjukkan bahwa struktur APO berfungsi dengan baikuntuk mempersiapkan kondisi lingkungan yang memungkinkan dilakukan rehabilitasimangrove. Metoda ini merupakan perpaduan antara hard structure dengan softstructure sebagai upaya pemulihan daerah erosi pantai di Desa Timbulsloko, Demak.Metoda ini perlu dilanjutkan dan diterapkan di daerah lain dengan karakteristik pantaiyang serupa. ABSTRACT As an effort to reduce the northern coastal area erosion of Central Java hasestablished hard-structure (wave-breaker structure and permeable dam). Function ofwave-breaker structure and permeable dam are to reduce wave energy and to catchsediment until formed a relatively stable sedimentation land for planting mangrove -method of soft-structure- which in the long term of mangrove roots growth will benaturally restore for beach stability function.This research is observe sedimentation process around wave-breaker and permeabledam area until can be used to mangrove planting. Research method use descriptiveexploration. Sampling activity used purpose sampling method for the data of hydrooceanography,sediment and coastal line changes. Sediment analysis is used torehabilitation of mangrove.Hydro-oceanography observation result is needs to be input in sedimentation rate.Sedimentation in wave-breaker segment-1 show that 7 months observation can becollected 4,519 m2 (21.52 m3 per day) and segment-2 was 4,836 m3 (26.87 m3perday).Six months observation in permeable dam can collected 3,849m3 (21,38 m3 perday). Recommendation species of mangrove suitable to be planted in the location areRhizopora mucronata and Rhizopora stylosa. CEDAS Modelling results in 6 monthscan be collected sediment 3,550 m3.Sedimentation formed shows that wave-breaker and permeable structure works wellto prepare the environmental conditions to allow performed mangrove rehabilitation.This method is a combination of hard structure and soft structure for restoring coastalerosion area in Timbulsloko Village, Demak Regency. This method needs to befollowed and applied in other areas with similar characteristics coast.;As an effort to reduce the northern coastal area erosion of Central Java hasestablished hard-structure (wave-breaker structure and permeable dam). Function ofwave-breaker structure and permeable dam are to reduce wave energy and to catchsediment until formed a relatively stable sedimentation land for planting mangrove -method of soft-structure- which in the long term of mangrove roots growth will benaturally restore for beach stability function.This research is observe sedimentation process around wave-breaker and permeabledam area until can be used to mangrove planting. Research method use descriptiveexploration. Sampling activity used purpose sampling method for the data of hydrooceanography,sediment and coastal line changes. Sediment analysis is used torehabilitation of mangrove.Hydro-oceanography observation result is needs to be input in sedimentation rate.Sedimentation in wave-breaker segment-1 show that 7 months observation can becollected 4,519 m2 (21.52 m3 per day) and segment-2 was 4,836 m3 (26.87 m3perday).Six months observation in permeable dam can collected 3,849m3 (21,38 m3 perday). Recommendation species of mangrove suitable to be planted in the location areRhizopora mucronata and Rhizopora stylosa. CEDAS Modelling results in 6 monthscan be collected sediment 3,550 m3.Sedimentation formed shows that wave-breaker and permeable structure works wellto prepare the environmental conditions to allow performed mangrove rehabilitation.This method is a combination of hard structure and soft structure for restoring coastalerosion area in Timbulsloko Village, Demak Regency. This method needs to befollowed and applied in other areas with similar characteristics coast., As an effort to reduce the northern coastal area erosion of Central Java hasestablished hard-structure (wave-breaker structure and permeable dam). Function ofwave-breaker structure and permeable dam are to reduce wave energy and to catchsediment until formed a relatively stable sedimentation land for planting mangrove -method of soft-structure- which in the long term of mangrove roots growth will benaturally restore for beach stability function.This research is observe sedimentation process around wave-breaker and permeabledam area until can be used to mangrove planting. Research method use descriptiveexploration. Sampling activity used purpose sampling method for the data of hydrooceanography,sediment and coastal line changes. Sediment analysis is used torehabilitation of mangrove.Hydro-oceanography observation result is needs to be input in sedimentation rate.Sedimentation in wave-breaker segment-1 show that 7 months observation can becollected 4,519 m2 (21.52 m3 per day) and segment-2 was 4,836 m3 (26.87 m3perday).Six months observation in permeable dam can collected 3,849m3 (21,38 m3 perday). Recommendation species of mangrove suitable to be planted in the location areRhizopora mucronata and Rhizopora stylosa. CEDAS Modelling results in 6 monthscan be collected sediment 3,550 m3.Sedimentation formed shows that wave-breaker and permeable structure works wellto prepare the environmental conditions to allow performed mangrove rehabilitation.This method is a combination of hard structure and soft structure for restoring coastalerosion area in Timbulsloko Village, Demak Regency. This method needs to befollowed and applied in other areas with similar characteristics coast.] |