The Effect of Paraquat, Difenoconazole, and Butylphenyl Methylcarbamate (BPMC) on CO2 Emissions and Phenolic Acids in Peat Soil

Pesticides are widely used in agriculture, including on peat soil. The objective of this study was to analyze the effect of the application of paraquat, difenoconazole, and butylphenyl methylcarbamate (BPMC) on CO2 emissions and concentrations of phenolic acids in a peat soil. Peat soil sample was taken in District of Pulang Pisau, Central Kalimantan. The peat soil was applied with 1.89 mg kg-1 paraquat, 1.72 mg kg-1 difenoconazole and 1.65 mg kg-1 butylphenyl methylcarbamate (BPMC), then the soil was incubated for 1, 2, 4 , 5, 7, 10, 14, 21, 26 and 30 days. The results showed that the application of pesticides on peat soil increased CO2emission, and decreased CH4 emission and phenolic acid concentrations up to 30 days of incubation. The CO2 emmisions were derived from C of degraded pesticides and from C of phenolic acids, although the oxidation reaction was not accompanied by the change of soil pH. Keyword: CO2 emission, phenolic acids, butylphenyl methylcarbamate (BPMC), difenoconazole, paraquat, peat soi

Correlation Analysis of Soil Biological, Chemical, Physical Properties at Various Altitudes in Bandung, West Java

Kabupaten Bandung memiliki ketinggian tempat antara 675 mdpl – 2,100 mdpl dengan suhu udara berkisar 14oC sampai dengan 30oC. Perbedaan ketinggian tempat dapat menimbulkan perbedaan iklim  dan cuaca sehingga dapat mempengaruhi transformasi hara dan populasi mikrob di dalam tanah. Penelitian ini bertujuan untuk mengetahui korelasi sifat biologi dan kimia tanah, serta kaitannya antara sifat kimia dan fisika tanah pada berbagai ketinggian tempat di Bandung, Jawa barat. Pengambilan sampel tanah menggunakan metode Purposive Random Sampling dengan 5 kali ulangan. Sampel tanah terganggu diambil pada kedalaman 0-20 cm sebanyak ±1 kg, sedangkan contoh tanah utuh diambil menggunakan ring sampler. Pengambilan sampel tanah meliputi empat ketinggian tempat yaitu ketinggian 600 mdpl penggunaan lahan tanaman kol, ketinggian 1000 dan 1200 mdpl penggunaan lahan tanaman selada, serta ketinggian 1400 mdpl penggunaan lahan perkebunan kopi. Hasil analisis menunjukkan bahwa pada ketinggian 1000 mdpl populasi bakteri pelarut fosfat (BPF) dapat tumbuh optimum sebesar 93.6 x 103 CFU g-1 dengan pH tanah agak masam, P-Total sangat tinggi, dan P-Tersedia sedang. Populasi fungi dapat tumbuh optimum sampai ketinggian 1200 mdpl. Total populasi fungi berkorelasi tinggi dengan unsur hara P-Total dan N-Total di dalam tanah. Respirasi tanah berkorelasi positif dengan semua parameter yang berhubungan dengan sifat kimia tanah. Nilai bobot isi terendah pada ketinggian 1200 mdpl bersesuaian dengan nilai C-organik dan porositas tertinggi pada ketinggian tersebut.Bandung district has an altitude between 675 masl – 2,100 masl with air temperatures ranging from 14oC to 30oC. Differences in altitude can cause differences in climate and weather, which can affect nutrient transformation and microbial populations in the soil. This study aims to determine the correlation of biological and chemical properties of soil at various altitudes in Bandung, West Java. Soil sampling using Purposive Random Sampling method with five replicats. Soil samples were taken at a depth of 0-20 cm as much as ±1 kg. Soil sampling includes four altitudes of the place, altitude of 600 meters above sea level (masl) with the land use of cabbage plants, altitude of 1000 masl and altitude of 1200 masl with the land use of lettuce plants, and altitude of 1400 masl with the use of coffee plantation land. The results of the analysis showed that the height of 1000 masl of the phosphate solubilizing bacteria (BPF) population can grow optimally by 93.6 x 103 CFU g-1 with a slightly acidic soil pH, very high P-Total, and medium P-Available. The fungi population can grow optimally to an altitude of 1200 masl. Total fungi populations are highly correlated with P-Total and N-Total nutrients in the soil. Soil respiration is positively correlated with all parameters related to the chemical properties of the soil