Peran Vegetasi Dominan Pada Karakteristik Tanah di Lahan Bera, Kampung Womnowi, Distrik Sidey, Manokwari

Abstrak: Selama proses suksesi, vegetasi merupakan satu dari komponen utama untuk meningkatkan kesuburan tanah. Tujuan penelitian ini adalah untuk menganalisis dan mendeskripsikan peran vegetasi dominan pada karakteristik tanah di lahan bera berumur 15 tahun Kampung Womnowi, Distrik Sidey, Manokwari. Vegetasi dominan ditentukan berdasarkan data indeks nilai penting (INP) analisis vegetasi. Sampel tanah diambil secara komposit pada luasan lahan 1 hektar dari dua kedalaman tanah (0–10 cm dan 10–20 cm). Vegetasi yang mendominasi lahan bera secara berurutan adalah Pometia pinnata, Dracontomelon dao, Octomeles sumatrana, Lansium domesticum, dan Pimelodendron amboinicum. Kehadiran O. sumatrana mengindikasikan lahan bera tanah aluvial, lebih lanjut terbukti karena lahan bera tersebut berdekatan dengan Sungai Womnowi. Karakteristik fisik tanah didominasi oleh fraksi lempung dan unsur makro lebih tinggi pada kedalaman 0–10 cm dibanding kedalaman 10–20 cm. Karakteristik tanah menunjukkan bahwa tanah tergolong masam (pH 5.4–5.6), kadar karbon organik tanah sedang (1.07–3.39%), kadar nitrogen total rendah (0.17–0.53%), kadar fosfor tersedia tergolong tinggi (10.7–22.4 ppm), kapasitas tukar kation (KTK) tergolong tinggi (10.50–20.32 cmol kg-1), kejenuhan basa tergolong sangat tinggi (65.4–66.7%), dan kadar Al3+ and H+ sangat rendah. Secara keseluruhan urutan KTK menunjukkan Ca > Mg > Na > K yang mengonfirmasi tanah aluvial dan pencucian kalium terjadi dengan cepat. Rendahnya kadar kalium dapat dihubungkan dengan penggunaan unsur tersebut untuk pembentukan buah L. domesticum. Selama pemberaan 15 tahun, vegetasi dominan memengaruhi karakteristik tanah.Kata kunci: vegetasi pohon, kesuburan tanah, analisis tanah, aluvial, Papua BaratAbstract: During succesional season vegetation is one of major compound to increase soil fertility. The purpose of this study was to analyzed and description dominant vegetation and their contribution to soil characteristic at fallow land 15 years old Womnowi Village, Sidey District, Manokwari. To determine dominant vegetations we used data important value index (IVI) of vegetation. Two depth of sample soils (0–10 cm dan 10–20 cm) were taken from one hectare area by composite technique. The dominant vegetation on fallow land dominated by Pometia pinnata, Dracontomelon dao, Octomeles sumatrana, Lansium domesticum, and Pimelodendron amboinicum respectively. Presence of O. sumatrana was indicated that the type of aluvial fallow land, further it is proven because the fallow land is close to the Womnowi River. Soil physical characteristic dominated by clay fractions, macronutrient was higher in depth 0-10 cm than 10-20 cm. Characteristic of soil shows acidic soils (pH 5.4–5.6), moderate of soil organic carbon (1.07–3.39%), total of nitrogen was low (0.17–0.53%), high available phosphorus (10.7–22.4 ppm), moderate cation exchange capacity (CEC) (10.50–20.32 cmol kg-1), very high base saturation (65.4–66.7%), and very lows of Al3+ and H+. Overall the order of CEC shows Ca > Mg > Na > K respectively confirmed aluvial soil and fast leached potassium in soil. Low potassium levels are thought be related to the use of the element for fruits formation of L. domesticum. During 15 year fallowed, dominant vegetation had influence to soil characteristic.Key words: tree vegetation, soil fertility, soil analysis, alluvial, West Papua

CADANGAN KARBON PADA TEGAKAN POHON HUTAN KOTA DI TAMAN MARGASATWA RAGUNAN DKI JAKARTA

Increase environmental problems, such as air pollution and temperatures increase in DKI Jakarta, make the existence of urban forests very important. Trees have an important role becausethey function as the most efficient carbon sink and storage in urban areas. Along with the<br />increasing number of visitors carrying vehicles, the higher the potential for air pollution in Ragunan Wildlife Park (TMR). The objectives of this study are: To analyze the community structure of tree species that have potential carbon stocks, and estimate carbon stocks stored in tree trunks. The study was conducted in four regions (north, west, east, south) Ragunan Wildlife<br />Park, DKI Jakarta. Vegetation analysis was carried out by calculating the Important Value Index (INP), and carbon stock analysis was carried out through the Allometric approach. The highest INP value was mahoni (Swietinia macrophylla) amounting to 45.51%, cengal pasir (Hopea<br />odorata) 33.31%, and dao (Dracontomelon dao) 28.26%. The largest amount of carbon reserves is found in the western region, which is 52,503 kg / ha, and the largest contribution of carbon stocks is from dao trees (Dracontomelon dao) of 30,091 kg / ha, cengal sand 25,372 kg / ha, oil<br />palm (Elaeis guinensis).

KEANEKARAGAMAN TUMBUHAN INANG LARVA KUPU-KUPU DI TAMAN WISATA ALAM SURANADI

Potensi flora dan fauna di Taman Wisata Alam Suranadi cukup melimpah salah satu diantaranya adalah kupu-kupu. Kupu-kupu memiliki peranan yang sangat penting sebagai pollinator dan bioindikator terhadap perubahan kualitas lingkungan. Keberadaan dan keanekaragaman kupu-kupu sangat dipengaruhi oleh penyebaran dan kelimpahan tumbuhan inang terutama pada masa larva. Penelitian bersifat deskriptif eksploratif menggunakan metode jelajah. Tumbuhan inang ditentukan berdasarkan keberadaan larva dan kerusakan daun akibat gigitan ulat kupu-kupu. Tumbuhan inang yang ditemukan dikoleksi dan diidentifikasi menggunakan buku identifikasi Flora of Java, Flora of Malesiana dan URL: http://www.theplantlist.org. Data hasil pengamatan dianalisis secara kuantitatif untuk menentukan kerapatan relatif, frekuensi relatif dan indeks diversitas Shannon–Wiener (H’). Berdasarkan hasil analisisi data, ditemukan 26 spesies dari 18 famili tumbuhan yang berpotensi sebagai tumbuhan inang larva kupu-kupu. Spesies tumbuhan inang yang dominan yaitu Chlorantus officinalis diikuti oleh Dracontomelon dao dengan Indeks diversitas sebesar 4,1.