SOIL PROPERTIES OF EIGHT FOREST STANDS RESULTED FROM REHABILITATION OF DEGRADED LAND ON THE TROPICAL AREA FOR ALMOST A HALF CENTURY (Sifat-sifat Tanah Delapan Tegakan Hutan Hasil Rehabilitasi Lahan Terdegradasi pada Daerah Tropika Selama Setengah Abad)

ABSTRACTPhysical, chemical and biological properties of soil are influenced by vegetation types which grow above it. Different tree species of stands will produce difference litter quantity, litter quality and also plants’ root system. Therefore quantifying physical and chemical soil properties in several stands after rehabilitation of degraded land will increase the understanding of forest soil characteristics. The research was conducted in 8 forest stands in Wanagama I, Gunungkidul, Yogyakarta. Collection of soil samples was done at the depth of 0-10, 10-30 and 30-50 cm by making soil profile. The result showed that the textural classes were from sandy clay loam to clay. The content of clay increased with increasing soil depth. Bulk density did not differ much among the profiles and soil depth, ranging from 0.90 to 1.28 g/cm3, and so were particle density ranged from 2.19 to 2.55 g/cm3 and pore space ranged from 47.89 to 58.08 %. pH H2O ranging from 5.81 to 7.49 (slightly acid to neutral), meanwhile  pH KCl ranging from 4.44 to 6.37. C-organic content varied widely among the vegetations and soil depth ranged between 0.11 and 5.17 %. Available P and total P varied widely from 1 to 104 ppm and from 20 to 390 ppm, respectively. CEC were not much different among the profiles and soil depths, ranging from 19.80 to 38.06 cmol (+)/kg and base saturation in all samples were very high i.e. > 100 %. ABSTRAKSifat-sifat fisik, kimia dan biologi tanah dipengaruhi oleh tipe vegetasi yang tumbuh di atasnya. Perbedaan spesies pohon suatu tegakan akan menghasilkan perbedaan jumlah seresah, kualitas seresah dan juga sistem perakaran. Kuantifikasi sifat-sifat fisik dan kimia tanah pada beberapa tegakan hutan pada lahan terdegradasi setelah direhabilitasi akan meningkatkan pemahaman mengenai sifat-sifat tanah hutan. Penelitian dilakukan pada I jenis tegakan hutan di Hutan Pendidikan Wanagama, Gunungkidul, Yogyakarta. Pengambilan sampel tanah dilakukan pada kedalaman 0-10, 10-30 dan 30-50 cm dengan cara membuat profil tanah. Hasil penelitian menunjukkan bahwa kelas tekstur mulai dari geluh lempung pasiran sampai lempung. Kandungan lempung meningkat dengan semakin dalamnya tanah. Berat volume tidak banyak berbeda antar profil dan kedalaman tanah, berkisar antara 0,90 - 1,28 g/cm3, dan kerapatan partikel berkisar antara 2,19 - 2,55 g/ cm3, dan ruang pori tanah berkisar antara 47,89 - 58,08 %. pH H2O berkisar antara 5,81 - 7,49 (agak asam sampai netral), pH KCI berkisar dari 4,44 - 6,37. Kandungan C-organik sangat bervariasi antar jenis vegetasi dan kedalaman tanah mulai 0,11 - 5,17 %. Kandungan P tersedia dan P total sangat bervariasi, secaraberturut-turut dari 1- 104 ppm dan 20 - 370 ppm. Nilai KPK tidak banyak berbeda antar profil dan kedalaman tanah berkisar antara 19,80 - 38,06 cmol (+)/ kg dan kejenuhan basa untuk semua sampel mempunyai nilai sangat tinggi > 100 %

Pengggunaan tanaman penutup tanah jenis legum sebagai penyuplai unsur hara dan baran pembenah tanah di hutan tanaman industri

The effect of legume cover crop on soil characteristic was studied to evaluate the possibility of legume cover crop (LCC) as soil amelioration for the next generation of Gmelina arborea Roxb. plantation forest. Three species of LCC: Crotalaria anagyroides (CA), Mucuna chochuchinensis (MC) and Calopogoniurn caeruleum (CC) were planted at the former field of G arborea plantation forest with I plot for control. Above and belowground biomass were studied 4 months after planting (MAP), and soils were sampled 6 months after planting for laboratory analysis. CA is not a creeping plant and has a good suitability to grow well and fast to flower. The growth rate of MC was relatively high and could cover soil surface fastly. The initial growth rate of CC was relatively slow, but finally could cover soil surface well, thick and remain in a long time. Biomass in CA was 2.9 Mg ha\u27, MC was 2.6 Mg ha-\u27 and CC was 2.1 Mg ha-1. The organic matter and nutrient contents in the total biomass of LCC that could be supplied to the soil were 1,160-1,680 kg ha-\u27 for C30.-41 kg ha\u27\u27 for N,1.5-2 kg ha-1 for P,18-21 kg ha-1 for K, 9-12 kg ha.-1 for Ca, 0.70.9 kg ha-1 for Mg and 0.2 kg ha-\u27 for Fe at 4 months after planting (MAP). Organic matter and C, N, P, K, Ca, Mg and Fe content were higher than the other crop. Soil characteristics were affected by LCC, especially in the top layer. The concentrations of total-and available nutrient in the soil under LCC were relatively higher than control. Legume cover crops could increase the nutrient\u27s availability and become a good soil amendment for the forest land. Keywords: legume cover crop, organic matter, soil amendment, Gmelina arborea plantation fores

Kandungan Unsur Hara Daun Pinus Merkusi Jungh. et de Vriese dan Sifat-sifat Tanah di Tegakan dengan Produksi Getah yang Bervariasi

Secara ekonomi, peranan tegakan Pinus dari tahun ke tahun meningkat dari nilai getahnya dan telah menjadi produk unggulan di Perum PERHUTANI. Di beberapa KPH produksi getah antara petak satu dengan petak lainnya mempunyai variasi yang cukup besar, padahal berasal dari bibit yang sama. Penelitian ini bertujuan untuk mencari sifat tanah dan iklimnya yang berakibat pada kandungan hara daun yang diduga sebagai penyebab perbedaan produksi getah. Penelitian dilakukan di Ngablak dengan produksi getah rendah (>15 g/pohon/3 hari), kedua RPH terletak di KPH Kedu Utara. Penelitian dilakukan dengan membuat profil tanah pada masing-masing petak dengan 3 ulangan. Sampel daun segar diambil dengan memanjat pohon dengan memotong rantingnya, daun dan dianalisis unsur hara makro dan mikro. Hasil menunjukkan bahwa pada pinus di Ngablak terletak pada elevasi rata-rata 1.213 m dpl dan di Grabag pada elevasi 908 m dpl. Ketebalan solum di Ngablak hanya 60 cm, warna tanahnya lebih cerah (yellowish red) dan di dalam profil tanah terdapat banyak batu-batu yang keras, sedangkan di Grabag mempunyai solum > 90 cm, warna tanah lebih kelam (dark brown) dan tidak ada bahan kasar di dalamnya. Biomassa sersah, tinggi dan diameter di Ngablak hanya 1.317 ton/ha, 19,3 m dan 20,8 cm, sedangkan di Grabag 6.857 ton/ ha, 31,6 m dan 20,8 cm. Kandungan Mg dan Mn di Ngablak 0,14 ppm dan 86 ppm, sedangkan di Grabag 0,27 ppm dan 283 ppm. Kandungan unsur hara C, N, P, K, Ca, Na, Fe, Cu dan Zn relatif tidak begitu berbeda.Katakunci: Pinus merkusii, produksi getah, unsur hara, elevasi, sifat tanah Nutrient Content of Pinus merkusi Jungh. et de Vriese Leaf and Its Soil Properties under Varied Resin Production Levels of StandsAbstractEconomically, the role of pine stands increased because of the value of the resin. The resin has been a flagship product of Perum PERHUTANI. In some areas, resin production varied among compartments. The variation is quite large even the trees were from the same seed origins. This study aimed to study the soil properties and climate, which results in variation of leaf nutrient content. Those were predicted as the cause of differences in the production of resin. The study was conducted in both RPH Ngablak (lower resin production, (15 g/tree/3 d), which are located in KPH Kedu Utara. Soil samples were taken in each compartment with three replications. Fresh leaf samples were collected and analyzed for the macro and micro nutrients. The results showed that the pine in Ngablak lies at an elevation of about 1,213 m, while in Grabag it lies on 908 m above sea level. The thickness of the soil’s solum in Ngablak was only 60 cm. The soil was brighter in colors (yellowish red) and many hard stones were found in soil’s profile. Whereas in Grabag the solum was > 90 cm, dark in color (dark brown) and no coarse material in the soil’s profile. Litter biomass, trees height and diameter in Ngablak were only 1,317 tons/ha, 19.3 m and 20.8 cm, respectively. While in Grabag, the litter biomass, trees height and diameter were accounted for 6,857 tons/ha, 31.6 m and 20.8 cm, respectively. The leaf content of Mg and Mn in Ngablak were 0.14 ppm and 86 ppm, respectively, while in Grabag were accounted for 0.27 ppm and 283 ppm, respectively. Nutrient content of C, N, P, K, Ca, Na, Fe, Cu and Zn in both areas were no significant different.

Potency Of N-Mderalization In 2 Kinds Of Forest Soils

ABSTRAK Penelitian ini dilaksanakan untukmengukur potensi mineralisasi nitrogen secara in vitro pada tanah hutan di bawah tegakan hutan Matebashii (Pasania edulis) dan Sudajii (Castanopsis cuspidata van Siebaldi) yang terletak di Propinsi Chiba, Jepang Potensi mineralisasi tanah hutan dihitung dengan menggunakan model kinetik sederhana secara in vitro pada inkubator yang mempunyai suhu 20°C, 25°C dan 30°C. Kadar NO3 dan NH: dianalisis secara periodik selama dalam inkubasi. Mineralisasi pada suhu 30°C ternyata lebih besar bila dibanding dengan pada 20°C dan 25°C untukMatebashii, tetapi tidakterialuberbeda untuk Sudajii. Mineralisasi tahunan untuk tanah hutan pada kedalaman 5 cm di bawah tegakan Matebashii hanya sebesar 78,92 kg.ha-1.th-1, atau hanya sekitar 50% dari mineralisasi N di bawah tegakan Sudajii (156,6 kg.ha-1.yr1). Karena potensi mineralisasi N pada tegakan Matebashii(No= 40,07 mg.100g-1tanah) adalah lebih rendahbila dibandingkan pada Sudajii (No= 43,11 mg.100etanah), maka energi aktivasinya (Ea=15.990 Ical.mo1-1) lebih tinggi bila dibanding dengan Sudajii (Ea= 6.072 kal.mo1-1). Konstanta laju mineralisasi pada tegakan Matehashii (k= 0.006 per hari) mempunyai nilai yang lebih rendah daripada di Sudajii (k= 0.011 per hari). Pengaruh pemanasan global menyebabkan Day at Temperature Standard (DTS) pada tegakan Matebashii akan meningkat 42% dart DTS pada tegakan Sudajii akan meningkat 12%. Dengandenulcian, mineralisasi N pada tegakan Matebashii di daerahpalingutara akan meningkat 17%. Meskipun mineralisasi N pada tegakan Sudajii 2X lebih banyak dibandingkan pada tegakan Matebashii, tetapi pengaruh pemanasan global hanya akan mening,katkan 2% saja. Kata kunci: mineralisasi nitrogen, tanah hutan, in vitro, suhu, pemanasan global

IMPACT OF TROPICAL RAIN FOREST CONVERSION ON THE DIVERSITY AND ABUNDANCE OF TERMITES IN JAMBI PROVINCE (Dampak Konversi Hutan Tropika Basah Terhadap Keragaman Jenis dan Kelimpahan Rayap di Provinsi Jambi)

ABSTRACTThe degradation of tropical rain forest might exert impacts on biodiversity loss and affect the function and stability of the ecosystems. The objective of this study was to clarify the impacts of tropical rain forests conversion into other land-uses on the diversity and abundance of termites in Jambi, Sumatera. Six land use types used in this study were primary forest, secondary forest, rubber plantation, oil-palm plantation, cassava cultivation and Imperata grassland. The result showed that a total of 30 termite species were found in the six land use types, with highest species richness and abundance in the forests. The species richness and the relative abundance of termites decreased significantly when the tropical rain forests were converted to rubber plantation and oil-palm plantation. The loss of species richness was much greater when the forests were changed to cassava cultivation and Imperata grassland, while their abundance greatly decreased when the forests were degraded to Imperata grassland. Termite species which had high relative abundances in primary and secondary forests were Dicuspiditermes nemorosus, Schedorhinotermes medioobscurus, Nasutitermes longinasus and Procapritermes setiger. ABSTRAK Kerusakan hutan tropika basah dapat menimbulkan dampak lingkungan berupa penurunan keanekaragaman hayati serta terganggunya fungsi dan stabilitas ekosistem. Tujuan dari penelitian ini adalah untuk mengetahui dampak konversi hutan tropika basah  menjadi bentuk penggunaan lahan lain di Jambi Sumatra terhadap keragaman jenis dan kelimpahan rayap. Enam tipe penggunaan lahan yang digunakan dalam penelitian ini adalah hutan primer, hutan sekunder, tanaman karet, tanaman kelapa sawit, kebun ketela pohon dan padang alang-alang. Hasil penelitian menunjukkan bahwa ditemukan 30 jenis rayap pada 6 tipe penggunaan lahan tersebut, dengan keragaman jenis dan kelimpahan individu rayap tertinggi pada lahan hutan. Kekayaan jenis dan kelimpahan relatif rayap menurun secara nyata apabila ekosistem hutan dikonversi menjadi tanaman karet dan kelapa sawit. Penurunan kekayaan jenis menjadi jauh lebih besar ketika hutan dikonversi menjadi kebun ketela pohon dan padang alang-alang. Kelimpahan individu rayap akan sangat menurun apabila terjadi perubahan ekosistem hutan menjadi padang alang-alang. Jenis-jenis rayap yang mempunyai kelimpahan tinggi pada ekosistem hutan adalah Dicuspiditermes nemorosus, Schedorhinotermes medioobscurus, Nasutitermes langinasus dan Procapritermes stiger

Dinamika Kandungan Unsur Hara Pada Proses Dekomposisi Beberapa Jenis Daun Tanaman Kehutanan

ABSTRACT In forest ecosystems, vegetation requires many chemical elements to live and grow. The minerals that are taken up into the forest trees are eventually returned to the surface of the forest soil by litterfall. Leaves are usually major contributor to the litterfall. Decomposition of the litterfall is one of the most important stages in the biogeochemical cycle of forest ecosystems. The decomposition rate determines the rate at which nutrients become available for renewed uptake by the vegetation. During the decomposition process, content of nutrient elements in the litter will increase and/or decrease because of soil organism activities and environmental factors. Therefore it is necessary to carry out research on the decomposition process of plant litter. The research entitled : "dynamics of nutrient element contents during decomposition of leaves of seven tree species" was carried out to clarify the dynamics of such nutrient element contents as nitrogen (N), phosphorus (P), potassium (K), calcium (Ca) and magnesium (Mg) during the decomposition process of seven tree species leaves under the forest stand dominated by legume trees. Some results from this research could be summarized as follows : The N contents in leaves of Pinus merkusii and Melaleuca letï´adyndron had a tendency to decrease, while on the other hand, those in leaves of Gmelina arborea, Gkrecidea maculata and Paraserianthesfakataria obviously showed increases. In the leaves of P. merkusii, M. leucadendron and G. arborea, the P contents had inconsistently a tendency of increases and decreases, while in P. falcataria and G. maculata tended to increase. The K contents in P. merkusii, Eucalyptus urophylla, Acacia mangium, and P. faicataria leaves showed a tendency of increases and decreases, and those in M. leucadendron and G. maculata tended to increase, while those in G. maculata had a tendency to decrease. During the decompositio

Perhitungan Nilai Nisbah Hantaran Sedimen Dengan Menggunakan Kurva Sedimen Dan Model Erosi Tanah

Prolonged soil erosion and sedimentation have negative effect on land quality showing by decreasing land productivity, in addition, sedimentation process may cause decreasing function of hydrologic infrastructures. In watershed scale it is important to monitor both important processes. The relationship between the amount of onsite erosion and sedimentation at the watershed outlet is formulated in the Sediment Delivery Ratio (SDR). SDR is the ratio between the erosion that occurs in the entire basin with the amount of sediment in the outlet of a watershed. This study aimed to calculate SDR value of two watersheds which have different topographic condition and land cover types composition. The study was conducted in two sub-watersheds namely Tapan and Ngunut I. Erosion calculation used USLE formulae while prediction of water discharge and sediment discharge utilized rating curve and sediment rating curve. The study shows that (1) SDR of Tapan is higher than SDR of Ngunut I, it indicates that there are others source of sediment beside sheet erosion which is transported to the outlet of watershed, (2) The value of SDR fluctuate according to fluctuations in monthly rainfall and runoff, (3) SDR is less sensitive to land cover types rather than of topographic factor (slope, drainage density an watershed area)

Studi Intersepsi Hujan pada Hutan Tanaman Eucalyptus Pellita di Riau

Penelitian ini bertujuan untuk mengetahui besarnya kehilangan air melalui intersepsi di hutan tanaman E. pellita, di Perawang-Riau. Untuk menghitung besarnya nilai intersepsi, dilakukan pengukuran aliran batang (stemfl ow) dan lolosan tajuk (throughfall) pada umur tanaman 2, 3, 4, 5, dan 6 tahun, masing-masing 3 ulangan pohon. Hasil penelitian menunjukkan besaran kisaran nilai intersepsi, throughfall dan stemfl ow masing-masing 13,3-18,7 %; 7,7-83,1 % dan 3,6-4,1 % dari curah hujan. Kapasitas tampungan tajuk (canopy storage capacity) tanaman E. pellita rata-rata sebesar 0,8 mm. Hubungan curah hujan dengan throughfall dan stemfl ow menunjukkan korelasi yang kuat (r2 rata-rata 0,99 dan 0,79), sedangkan dengan intersepsi korelasinya kurang kuat (r2 rata-rata 0,58)

Simulasi Model Dinamik Pengaruh Legume Cover Crops (Lcc) Terhadap Limpasan Dan Sedimen Di Lahan Hutan Tanaman (Dynamic Model Simulation of the Effects of Legume Cover Crops (Lcc) on Runoff and Sediment in Plantation Forest Land)

Declining productivity of plantation forest due to low soil fertility. This condition has forced managers to make efforts in manipulating the tree growing environment. One such effort is by introducing cover crops species from legumes (LCC), to control surface runoff, soil erosion and input nutrient into the soil. The research aims to determine the effectiveness of LCC in controlling total runoff and sedimentation in Eucalyptus pellita plantations, through dynamic model simulation. The dynamic model of STELLA version 9.0.2 was used to study water and nutrient cycles, focused on the application of LCC to reduce total runoff and sedimentation. The results showed that LCC could drop the total runoff of average 35% in the 1 - 2 years old. In the 1styear it decreased from 1,530 mm to 994 mm, while in the 2ndyear it decreased from 1,240 mm to 806 mm. The declining also occurred in the sediment content, in the 1st year it decreased from 12.20 tonnes/ha to 7.93 tonnes/ha, and the 2nd year it decreased from 6.63 tonnes/ha to 4.36 tonnes/ha. These research findings can be used by the environmental manager to minimize potential land degradation, especially during the post-harvest until the young plantations (0-2 years old) phases

FAKTOR-FAKTOR PENENTU KEKRITISAN DAN PENGEMBANGAN KRITERIA INDIKATOR KEKRITISAN EKOSISTEM GAMBUT TROPIKA DI TRUMON DAN SINGKIL PROVINSI ACEH (Determinant Factors of Criticality and Development Criteria Indicators for Critical Tropical Peat Ecosystem in Tr

ABSTRAKHutan rawa gambut merupakan salah satu ekosistem spesifik dan kompleks. Terbatasnya pemahaman terhadap karakteristik biofisik dan sifat kritisnya menjadi akar masalah degradasi ekosistem gambut di Indonesia. Generalisasi penerapan kriteria lahan kritis menyebabkan penilaian menjadi tidak tepat, sehingga program rehabilitasi menjadi tidak efektif. Tujuan penelitian adalah menentukan faktor-faktor biofisik yang mempengaruhi tingkat kekritisan ekosistem gambut, dan mengembangkan kriteria dan klasifikasi tingkat kekritisan ekosistem gambut. Pengumpulan data dilaksanakan pada berbagai tipe penutupan hutan dan tingkat keterbukaan lahan gambut di Trumon dan Singkil, Provinsi Aceh. Analisis data meliputi analisis korelasi bivariat, analisis gerombol, dan analisis diskriminan. Karakteristik biofisik yang diukur adalah dinamika kedalaman muka air tanah, penurunan permukaan tanah, tingkat dekomposisi, unsur hara, kehilangan karbon, dan penutupan lahan. Hasil penelitian menunjukkan perubahan penutupan lahan dan pembangunan drainase mempengaruhi tingkat kekritisan ekosistem gambut. Perubahan tingkat dekomposisi gambut (nisbah C/N), perubahan kemasaman (pH) dan dinamika kedalaman muka air tanah merupakan penciri penting tingkat kekritisan ekosistem gambut. Ketiga faktor penciri ini diharapkan menjadi masukan dalam penyempurnaan kriteria tingkat kekritisan lahan pada Permenhut No. P.32/Menhut-II/2009 terutama pada ekosistem gambut.ABSTRACTPeat swamp forest is one specific and complex ecosystem. The limited understanding of the biophysical characteristics and critical properties are some root of problems peat ecosystem degradation in Indonesia. Generalizing in application of critical land criterions caused incorrect assessment, therefore the rehabilitation and management programs became ineffective. The objectives of the study was to determine the biophysical factors that influence the degree of criticality of peat ecosystem, and to develop criterion and classification of the criticality degree on peat ecosystem. Data collection was conducted on variety of forest cover types in Trumon and Singkil, Aceh Province. Data analysis included bivariate correlation analysis, analysis of clusters, and discriminant analysis. Biophysical characteristics were measured including the dynamics of the depth of the water table, rate of subsidence, level of decomposition, nutrient content, loss of carbon, and land/forest cover. Results showed land use change and drainage affects the critical level of peatland ecosystems. The change on level of peat decomposition (C/N ratio), soil acidity (pH) and groundwater dynamics were the identifier of critical peatland ecosystems. In addition to the criteria in Regulation No. P.32 / Menhut-II/2009, the identifier factors were expected to be considered in the refinement of the criteria of the critical level of peat ecosystem