DISTRIBUSI DAN KEMELIMPAHAN LAMUN (SEAGRASS) SEBAGAI RESPON TERHADAP MUSIM DI PANTAI JEPARA
| Main Authors: | , NURUL KUSUMA DEWI, , Dr. Tjut Sugandawaty Djohan, M.Sc. |
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| Format: | Thesis NonPeerReviewed |
| Terbitan: |
[Yogyakarta] : Universitas Gadjah Mada
, 2012
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| Subjects: | |
| Online Access: |
https://repository.ugm.ac.id/101004/ http://etd.ugm.ac.id/index.php?mod=penelitian_detail&sub=PenelitianDetail&act=view&typ=html&buku_id=57993 |
Daftar Isi:
- The purpose of this research was to study the response of seagrass communities to the dry and wet seasons. The study areas were at Jepara Coast: Bandengan, abandon ponds, Prawean, and Pulau Panjang. The presence of seagrass communities was determined by the nutrients and light. In the wet season, high river discharge increased nutrients in the coastal waters. At location near the river, turbidity increased because of surface run off from the watershed. Data were collected using quadrat plots with two transects were placed across the litoral of upper and lower zones. At each transect of the zone, data was collected using the quadrat plot, 0.5 m x 0.5 m, with 10 replications. On each plot, number of species, density, and their growth include biomass, stem height, length and width of leaf were sampled. Parameter measured were water quality of light penetration, water level, current velocity, salinity, temperature, wave height, DO, pH, sediment texture, and nutrients of NH4, NO3, PO4, C-organic. The results showed there were 7 species of seagrass communities which distributed unevenly: Cymodocea rotundata, Cymodocea serrulata, Enhalus acoroides, Halodule uninervis, Syringodium isoetifolium, Thalassia hemprichii, and Thalassodendron ciliatum. The seagrass-species densities varied between locations. During the dry season, it between 13-855 individuals per 2.5 m2 (S. isoetifolium and H. uninervis). In contrast, during the rainy season was between 2-215 individuals per 2.5 m2 at upper littoral zone (E. acoroides and T. ciliatum) and 2-231 individuals per 2.5 m2 in the lower littoral zone (T. hemprichii and T. ciliatum). These variations were due to the increasing river discharges which increased the nutrients and turbidity. The two factors decreased the abundance of seagrass communities during wet season. H. uninervis was a seagrass species which was tolerant to high nutrient. While T. hemprichii was tolerant to turbidity. The high of nutrients triggerred the growth of epiphytic algae which interfered the process of photosynthesis and caused the growth of seagrass disturbed. Nutrients and light were factors that determined the presence and abundance of seagrass communities in Jepara Coast.