:Steady soil aggregationis important for agricultural land which is formed by the micro-

Sintesis, karakterisasi dan uji adsorpsi komposit zeolit magnetit telah dilakukan. Komposit zeolit magnetit disintesis menggunakan metode kopresipitasi campuran Fe2+ dan Fe3+ pada pH 11 dengan mempelajari pengaruh durasi pengadukan reaktan terhadap kristalinitas produk. Hasil sintesis dikarakterisasi dengan metode spektrofotometri Inframerah (FTIR) dan difraksi sinar-X (XRD). Aplikasi zeolit-magnetit sebagai adsorben Ni(II) dipelajari dengan mengkaji pengaruh variasi waktu adsorpsi dan kinetika adsorpsi. Hasil penelitian menunjukkan bahwa komposit zeolit magnetit dengan kristalinitas yang baik dan memiliki sifat kemagnetan berhasil disintesis menggunakan metode kopresipitasi. Komposit zeolit magnetit dengan kristalinitas paling baik terbentuk pada saat durasi pengadukan reaktan selama 1 menit. Adsorpsi Ni(II) oleh Komposit zeolit magnetit secara optimal terjadi pada waktu adsorpsi 100 menit dan mengikuti kinetika orde dua semu Ho dengan nilai konstanta laju adsorpsi (k) 1,45 x 10-3 g/mg menit. Uji pemisahan fasa padat pada komposit zeolit magnetit sebagai adsorben memerlukan waktu lebih cepat menggunakan medan magnet eksternal.

The use of (NH4)2SO4 fertilizer is vital in increasing plant growth and reducing the Pb content in soil. This study determined the ability of Codiaeum and Sansevieria to accumulate Pb due to (NH4)2SO4 fertilization and its effects on their growth rate. The ammonium fertilizer was applied three days after repotting according to these treatment levels: 0, 100, and 200 kg N/ha, denoted as P0, P1, and P2, respectively. The height of Codiaeum decreased by 45.04%, 24.67%, and 13.70% in treatment P0, P1 and P2, respectively, one week after repotting. The Pb concentrations in Codiaeum decreased with increasing doses of N fertilizer, while in Sansevieria, Pb concentrations increased with higher doses of N fertilizer. A reduction in the soil pH was seen with increasing dosage of N fertilization in Codiaeum, while the pH of the medium with Sansevieria was stable. Therefore, the effect of the different N doses, which causes a decrease in soil pH, was more significant in Codiaeum compared with Sansevieria. Furthermore, the highest value of TF was found in Codiaeum treated with 200 kg N/ha.

The use of antagonistic microbes and potassium fertilizer on potato cultivation at the medium land was carried out to improve plant endurance, yield and quality. Application of potassium doses and suitable antagonistic microbial types will strengthen plant cell walls and plant nutrients to be fulfilled. This research aims to study the growth response, yield and quality of potato bulb in land medium with the application of antagonistic microbes and potassium fertilizer. The height of the land is around 670 meters above sea level, the texture of the clay and the experimental design used is the Split Plot Design. Three kinds of antagonistic microbes are A1 (Pseudomonas fluorescens), A2 (Streptomyces sp. + P. fluorescens), A3 (Trichodermaviride + Streptomyces sp. + P. fluorescens), and three types of Potassium doses are: D1= 125 kg Ha-1 KCl, D2 = 250 kg Ha-1 KCl, D3 = 375 kg Ha-1 KCl. Each treatment has three replications, the number of plants per experiment plot is 22 plants, and the sample plants used in each trial plot are 6 plants. The results showed that the administration of P.fluorescens + Streptomyces sp. + T. viride and 250 kg Ha-1 KCl and 375kg Ha-1 KCl doses tend to produce growth, tuber fresh weight per hectare, tuber dry weight percentage, tuber specific gravity and higher sugar content than other treatments.

This research aimed to apply a phytoremediation process  by adding fertilizer to increase the biomass of hyperaccumulator plants. This research was an experiment conducted in the Greenhouse and Laboratory of  Faculty of Agriculture,University of Islam Malang which began in September to November 2018. This experiment used a factorial randomized block design (RBD) consisting of 2 factors. The first factor was the administration of several Doses of ZA consisting of three levels, namely control (P0), ZA 100 kg N ha-1 (P1), ZA 200 kg N ha-1 (P2) and the second factor of plant species consists of two levels, (puring plants (T1), lidah mertua plants (T2)). The results showed that the calculation of TF of Pb ranged from 0.64 to 0.95. It   is  categorized into phytoremediation phyto-stabilizationcategoy.  The optimal dosage of ZA for puring plants needed was 95 kg N ha-1  with Pb Absorption 0,43875 ppm, whole the optimal dosage of ZA for lidah mertua plants was 116,7 kg N ha-1 with Pb absorbtiohn  0,37383 ppm.  Keywords: ZA fertilizer, Pb accumulation, Codiaeum variegatum L., Sansevieria trifasciata L.