Judul: Status Kecemaran Tanah oleh Kadmium pada Lahan Budidaya Sawi Putih (Brassica chinensis L.) di Sentra Produksi Hortikultura Lembang, Jawa Barat.
Abstrak: The source of cadmium (Cd) contamination in arable land, among others, is the use of manure and P fertilizer. Therefore, its long-term application at excesive dosage, as those practized by farmers in horticulture production centers, many cause Cd accumulation in soil and plant tissues. It is the main route of Cd intoxication into human body, therefore it poses health risk. The objective of this research was to explore the Cd pollution status in soil and its concentration in leaves of chinese cabbage (Brassica chinensis L.) cultivated in horticulture production center of Lembang, West Java. The study site was parts of an intensively cultivated land area for horticulture commodity. Field observation and soil (composite, 0-20 cm) and plant tissue (leaf) sampling were conducted at 16 points represented uncultivated control land [Lc] and 3 categories of land productivity level (high [Ph], medium [Pm] and low [Pl]). Soil analysis was conducted on texture; pH (H2O 1:1); Corganic; POlsen; Cdaqua regia (HNO3:HCl =1:3) and CdNH4OAc-EDTA (0.5 M NH4OAc + 0.002 M EDTA pH 4.65). Plant tissue analysis was performed for Cdplant concentration (dry ashing, 0.2 M HNO3). Soil Cd pollution level was evaluated based on the value of contamination/pollution (c/p) index according to the Lacatusu (2000) procedure. Average concentration of soil Cdaqua regia (mg/kg) at Pm (2.26) > Lc (2.02) > Ph (2.01) > Pl (1.43), with average soil Cd pollution status from very light pollution at Lc (value of c/p 1.96) to light pollution level at Pl (c/p 2.19), Ph (c/p 2.97) and Pm (c/p 3.26). Soil pollution level at Pl, Pm and Ph that was higher than that of Lc revealed the contribution of anthropogenic factors or sources, among others was the accumulation from the application of Cd-containing fertilizers. The amount of Cd absorbed by plant increased with the increasing concentration of soil Cd active fraction or CdNH4OAc-EDTA. Concentration of Cdplant at Ph was the lowest eventhoug its absorption was the highest. This was due to the occurrence of dilution effect related to the higher biomass yield. Concentration of Cdplant (0.10-0.39 mg/kg) has exceeded the maximum acceptable limit for vegetables (0.2 mg/kg) according to Codex Alimentarius Commision and, hence, its consumption higher than the tolerable dose will pose more health risk. Keywords:Brassica chinensis L., Cd, c/p index, Soil pollution.
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Judul: In situ inactivation of cadmium and plumbum pollution in arable soils using ameliorants and fertilizers at rationale dosage for crop crop cultivation
Abstrak: Arable soils in the vicinity of urban and industrial area are considered vulnerable to heavy metals pollution. This study was aimed at: (1) to explore the cadmium (Cd) and plumbum (Pb) contamination/pollution status in arable soils of the case study area (Middle-stream Cileungsi sub-sub-watershed area, Bogor district, West Java) and to evaluate the effects of pedogenic (pH H2O, clay, and organic matter content) as well as anthropogenic factors (straight nearest-distance from sampling points to the main road, toll road, industrial center, and elevation posisition of the sampling points), including soil depth, transect position, land-use type, and seasonal factors, on the pseudo-total soil Cd (CdAR) and Pb (PbAR) content, and (2) to investigate the effectiveness of rationale dose of ameliorants and fertilizers (RDAF) normally recommended for crop cultivation from the point of view to inactivate in situ and reduce the active-fractions of soil Cd and Pb (Cdand PbNH4OAc-EDTA) and plant-shoot Cd and Pb concentration (Cdps and Pbps) using tomato as the test plant through 100-day greenhouse experiments.
Keyword: Jawa Barat, Ameliorasi, Analisis Linier Berganda

Judul: Penggunaan Teorema Homeomorphy 2-Manifold dan Teorema Euler Poincare pada Torus 𝑇�� dan Simplicial Complex 𝐾��
Abstrak: Two dimensional topological spaces are said to be homeomorphic if they have the same topological invariant, where one of topological invariant used is an Euler characteristic. Homeomorphy 2-Manifold’s Theorem and Euler Poincare’s Theorem are used to distinguish two topological spaces. Homeomorphy 2-Manifold’s Theorem uses Euler characteristic to identify two dimensional topological spaces. Euler Poincare’s Theorem is an alternative way to find Euler characteristic with Betti number, which is topological invariant as well. The objective of this paper is to investigate the homeomorphism of torus 𝑇����� and simplicial complex 𝐾�����. Topological space torus and simplicial complex 𝐾����� have the same Euler characteristic, which is two. Based on Homeomorphy 2-Manifold’s Theorem topological space torus 𝑇����� and simplicial complex 𝐾����� is homeomorphic.
Keyword: simplicial, torus, Euler, homeomorphism, topology