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"Acacia man glum V/illd, merupakan tanaman penghijauan dan tanaman yang kayunya mempunyai nilai ekonomi tinggij yang dapat digunakan untuk bahan baku pembuatan kertas, perabot rumah tangga, kayu bakar dan arang= Dalam upaya untuk menin^atkan budidaya tanaman A. man glum serta menunjang keberhasilan dalam proses pembentukan bintil akar bagi penin^>?;atan pertumbuhan tanaman tersebutj maka telah dilakukan penelitian pengaruh inokulasi bakteri Rhizobium sp. dengan berbagai tingkatan variasi kepekatan optik atau "Optical Density" sebesar 0,10; 0,20 dan 0,30 pada kecambah A. mangium terhadap pertumbuhan dan jumlah bintil akar tanaman, Basil Uji Beda Nyata dari Tukey pada taraf nyata o< =- 0,01 menunjukkan bahv;a inokulasi bakteri Rhizobium sp, dengan berbagai tin^atan variasi kepekatan optik berpengaruh terhadap pertumbuhan tanaman (Tinggi, berat basah dan berat kering) pada umur 2 dan 3 bulan dan terhadap pembentukan bintil akar pada umur 3 bulan, Inokulasi bakteri dengan OD sebesar 0,10; 0,20. dan 0,30 tidak memberikan pengaruh nyata antara ketiga perlakuan tersebut, tetapi menunjukkan pengaruh nyata jika dibandingkan terhadap kontrol. Dari hasil penelitian ini dapat disimpulkan bahv^a inokulasi bakteri dengan OD sebesar 0,10 optimum untuk pertumbuhan tanaman 4* tnangium sampai dengan umur 3 bulan«"

"Kandungan ion logam Timbal dalam air cenderung sangat rendah sehingga proses analisisnya memerlukan teknik prakonsentrasi menggunakan resin penukar ion. Penggunaan resin penukar ion dalam teknik prakonsentrasi memiliki kelebihan, diantaranya faktor kehilangan analit dapat diminimalkan dan jumlah resin yang digunakan sedikit dan ramah lingkungan. Pada penelitian ini, ekstrak tanin daun Akasia Mangium digunakan sebagai bahan baku pembuatan resin penukar ion. Reaksi polimerisasi ekstrak tanin dengan penambahan H2SO4 pekat dilakukan agar resin tidak mudah larut dalam air. Hasil polimerisasi ekstrak tanin PET dikarakterisasi secara kualitatif menggunakan spektroskopi Fourier Transform Infra Red FTIR dan kuantitatif dengan pengukuran Total Karbon Organik TOC . Untuk mengetahui kemampuannya sebagai resin penukar ion, PET diuji dengan parameter adsorpsi, pola isoterm adsorpsi, dan validasi metode analisis. Kapasitas adsorpsi optimum resin PET diperoleh sebesar 5,261 mg/g pada pH 7 dan waktu kontak 120 menit, sedangkan parameter retensi optimum diperoleh pada konsentrasi eluen HNO3 2 M dengan volume 5 mL. Isoterm adsorpsi yang sesuai untuk resin PET mengikuti isoterm Freundlich dengan nilai regresi 0,9919. Berdasarkan uji validasi metode analisis diperoleh nilai kebolehulangan dengan RSD sebesar 0,97 , linearitas R2 0,9986 pada rentang 0,25-100 ppm, sensitivitas sebesar 0,067 ppm, batas deteksi Limit of Detection/LOD sebesar 0,019 ppm dan recovery sebesar 102,3 -110,91 . Hasil uji sampel menunjukan kadar Timbal di sungai Ciliwung sebesar 105-267 ppb.

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The heavy metal ions contained in water tend to be so low that the analysis process requires preconcentration techniques using ion exchange resins. The use of ion exchange resins in preconcentration techniques has advantages, such as factors for loss of analyte can be minimized and the amount of resin used is small and environmentally friendly. In this study, Acacia Mangium leaf tannin extract was used as the raw material for ion exchange resin production. The polymerization reaction of tannin extract with the addition of concentrated H2SO4 is done so that the resin is not easily soluble in water. Results from polymerization of tannin extract PET were characterized qualitatively using Fourier Transform Infra Red FTIR and quantitative spectroscopy with Total Organic Carbon TOC measurements. To find out its ability as ion exchange resin, PET was tested with adsorption parameters, adsorption isotherm patterns, and validation of analytical methods. The optimum adsorption capacity of PET resin was obtained at 5,261 mg g at pH 7 and contact time of 120 min, while the optimum retention parameter was obtained at eluent concentration of HNO3 2 M in 5 mL of volume. The adsorption isotherms suitable for PET resins that follow Freundlich isotherms with a regression value of 0.9919. Based on the validation test of the analysis method, the value of repeatability with RSD is 0.97 , the linearity of R2 0.9986 in the range of 0.25 100 ppm, the sensitivity of 0.067 ppm, the limit of detection Limit of Detection LOD of 0.019 ppm and the recovery of 102.3 110.91 . The result of the sample test shows that the Lead level in Ciliwung River is 105 267 ppb."

"The research was aimed to study the responses of plant growth and nutrient level to the application of humic acid,mycorrhizal fingi and rhizobium on acid and high al level of growth media,and their relationship to the adaptability LCC species through physiological mechanism of tolerance to al stress....."

"Heart rot on acacia mangium willd. forest stand is critical espicially for mechanical or construction wood based purposes. Failure on understanding the nature and the way it get estabilished into the tree stem may cause high economic consequences...."

"Natural mortality of trees is extremely variable due to the uncertainty and complexity of the functioning of forest ecosystems. The objective of this study was to develop a stand-level mortality model for Acacia mangium species by relating mortality to stand variables that affect the natural mortality process. The model was developed using data from l97 permanent sample plots measured periodically at 1-yr time intervals from 2-4 years until 8-11 years after planting in South Sumatra, Indonesia. The model consists of two complementary equations. The first equation is a logistic function predicting the probability of mortality incidence depending on stand density, site index and stand age. The second equation estimates the reduction in the number of surviving stems observed in a stand where natural mortality occurs. Nine equations were fitted using data from permanent sample plots where trees died over the time period and the best model was selected. Estimates from this second model were then adjusted by a factor equal to the probability of mortality applying three different approaches: probabilistic two-step, deterministic threshold and stochastic. All methods revealed no significant difference between the observed and the predicted number of surviving stems per ha. The probabilistic two-step approach, however, produced more consistent and the most accurate estimates. This method should provide reliable prediction when it is to be used in forest productivity prediction and management system for the species."