EKOLOGI VEGETASI PEKARANGAN : STUDI KASUS DI KABUPATEN MINAHASA

Semuel Paulus Ratag, Dr.Ir. Suryo Hardiwinoto

1996 | Tesis | S2 Ilmu Kehutanan

Usaha perbaikan dan pengembangan pekarangan merupakan salah satu altematif untuk mengatasi kendala-kendala dalam pembangunan kehutanan di Indonesia. Usaha tersebut harus dilandasi informasi mengenai komposisi dan struktur vegetasi, tanggapan pertumbuhan den adaptasi jenis serta interaksinya dengan faktor-faktor lingkungan. Studi ini bertujuan untuk mengetahui beberapa aspek ekologi pekarangan, terutama masing-masing stratum tajuk pada berbagai ketinggian tempat dart permukaan laut, antara lain : 1) komposisi dan struktur vegetasi pekarangan, 2) pengaruh faktorfaktor lingkungan terhadap komposisi den struktur vegetasi pekarangan, 3) laju fotosintesis, laju respirasi, dan titik kompensasi cahaya masing-masing jenis, 4) pengaruh faktor-faktor lingkungan terhadap laju fotosintesis, laju respirasi, dan titik kompensasi cahaya. Penelitian ini meliputi 15 releve yang merupakan kombinasi dari 3 ketinggian tempat dari permukaan laut dan 5 stratum tajuk. Data jumlah indMdu setiap jenis , laju fotosintesis, laju respirasi, dan titik kompensasi cahaya dianalisis dengan metode ordinasi dua dimensi. Hubungan antara pola pengelompokan releve dengan faktor-faktor lingkungan dipelajari dengan analisis korelasi sederhana. Keanekaragaman jenis diketahui dengan menghitung indeks Shannon. Hasil penelitian menunjukkan bahwa komposisi vegetasi pada stratum I (< 1 m) didominasi oleh Zingiber offlcinale, Curcuma domestics, Cordy/ine fruticosa, Allium fistu/osum, Durante repens, dan D. vsriegsts, stratum II (1-2 m) didominasi oleh Cordy/ine fruticosa, Manihot utilissims, Sauropus androgynus, Colocasia esculenta, dan Muse paradisiaca, stratum Ill (2-5 m) didominasi oleh Menihot uti/issil118, Musa paradisiaca, Caries papaya, dan Coffea robusta, stratum N (5-10 m) didominasi oleh Musa paradisiaca, Syz.ygium aromaticum, Caries papaya, lansium domesticum, Persea americana, dan Psidium guajeva, sedang stratum V (> 10 m) didominasi oleh Cocos nucifera, Psngium edu/e, Mangifera odorata, Arenge pinnate, den Artocerpus heterophy/lus. Strata tajuk menunjukkan bahwa semakin tinggi stratum tajuk, semakin rendah jumlah jenis dan jumlah individu per jenis. Laju fotosintesis, laju respirasi dan titik kompensasi rata-rata di setiap srata tajuk menunjukkan adanya perbedaan. Strata tajuk menunjukkan bahwa semakin tinggi stratum tajuk, semakin tinggi laju fotosintesis, laju respirasi, dan titik kompensasi cahaya. Pola pengelompokan releve berdasarkan jumlah individu per jenis, laju fotosintesis, laju respirasi, dan titik kompensasi cahaya lebih ditentukan oleh stratifikasi tajuk. lntensitas cahaya merupakan faktor lingkungan yang paling berpengaruh terhadap pola pengelompokan tersebut. Keanekaragaman jenis di seluruh lokasi penelitian adalah sebesar 4,41. Berdasarkan ketinggian tempat d.p.l., nilainya berkisar 1,27 - 2,29. Berdasarkan strata tajuk, nilainya cenderung semakin menurun dengan semakin tinggi stratum tajuk.

mprovement and development of home garden is one of the many alternatives to overcome some of the constraints faced by forestry development in Indonesia. It must be based on the information of vegetation composition and structure, growth response and adaptation of each species, as well as its interaction with environmental factors. The obejctives of the study were to determine several ecological aspects of home garden, especially on each stratum of the canopy on various altitudes, e.g. : 1) composition and structure of the vegetation, 2) effect of environmental factors, 3) rate of photosynthesis and respiration, and the light compensation point of any species, 4) effect of the environmental factors on the rate of photosynthesis and respiration, and the light compensation point. There were 15 releves of the research. Those were the combination of three altitudes with five canopy levels. The data of individual amount of each species, photosynthesis rate, respiration rate, and light compensation point were analyzed by using two dimensional ordination method. Relationship between grouping pattern of releves with environmental factors was analyzed by using simple correlation. Species diversity was computed by using Shannon Index. The results indicated that vegetation composition at stratum I ( < 1 m) was dominated by Zingiber officina/e, Curcuma domestics, Cordy/ine fruticoss, Al/ium f/stu/osum, Durante repens, and D. variegets, stratum II (1-2 m) was dominated by Cordy/ine fruticoss, Msnihot uti/issims, Sauropus andf'Ogfnus, Co/ocssia esculents, and Muss paradisieca, stratum Ill (2-5 m) was dominated by Manihot utilisslma, Muss paradisisca, Caries papaya, and Coffea robusta, stratum IV (?10 m) was dominated by Musa paradls/eca, Syzygium aromsticum, Car/ca papaya, lsnsium domesticum, PerstJB americsna, and Psidium guajava, stratum V (>10 m) was dominated by Cocos nucifera, Pangium edu/e, Mangffera odorats, Arengs pinnata, Artocarpus hete,ophyllus. The canopy strata indicated that the higher the canopy, the lower the quantity of each individual species. The photosynthesis and respiration rates, as well as the light compensation point on each canopy stl'8ta different from each other. The canopy strata indicated that the higher the canopy, the higher the photosythesis rate, respiration rate, and light compensation point. The grouping pattern of releves based on individual quantity of each species, photosynthesis end respiration rate, es well as the compensation point were determined by stratification of canopy. Light intensity was the most influential to the grouping pattern. Diversity index in all of research location was 4.41. Based on altitude, it was between 1.27 to 2.29. Furthermore, based on the strata of the canopy, there was a tendency the diversity decrease if the canopy was higher.

Kata Kunci : Ilmu Kehutanan,Ekologi Vegetasi Pekarangan