Effects of land-use change in tropical peatlands on the microbial population and emissions of nitrous oxide (N 2 O), methane (CH 4 ) and carbon dioxide (CO 2 ) were studied in the field and laboratory. The study area covered secondary forest, paddy field and paddy-soybean rotation field in Indonesia.ATP content, and numbers of viable bacteria and fungi, cellulolytic bacteria and fungi, NH 4 + oxidizers and denitrifiers in a paddy-soybean rotation field and paddy field were reduced to 1-30% and 3-90% of those in secondary forest, respectively. The field measurements of greenhouse gas emissions showed that significantly more CH 4 was emitted from paddy field than secondary forest, but no significant difference in the emission of either N 2 O or CO 2 . The laboratory incubation experiment showed that the soil moisture level and land-use change significantly affected the emission of N 2 O, CH 4 and CO 2 . These results suggested that land-use change significantly affected the microbial population and emissions of greenhouse gases.
The purpose of this study was to analyze the influence of meteorological factors directly or indirectly through the concentration of particulate (PM10) on the incidence of Acute Respiratory Infections (ARI) in the District of South Banjarbaru, Banjarbaru. The method used in this research is cross-sectional study, where data meteorological factors, the concentration of particulate matter (PM10) and the incidence of ARI are collected simultaneously. Data meteorological factors and the concentration of particulate matter (PM10) derived from Banjarbaru Climatological Station, while data came from health ARI Banjarbaru and Sei Besar which is located in the district of South Banjarbaru. While the analysis used in this study were Path Analysis (path analysis) was an analysis of the relationship between the independent variables, intermediate variables, and the dependent variable was presented in the form of a diagram. The results showed the meteorological factors that had a direct impact on the incidence of ARI was the largest factor relative air humidity of by 18.7%, followed by a factor of 7.1% of air temperature, wind speed factor and its influence on the intensity of rainfall was below 1%. While the indirect influence of meteorological factors on the concentration of particulate matter (PM10) on the incidence of ARI in the District of South Banjarbaru effect was below 1%. It can be concluded that the direct effect of meteorological factors and the concentration of particulate matter (PM10) on the incidence of ARI in the District of South Banjarbaru significant factor was the relative air humidity and air temperature. While the indirect influence of meteorological factors against ARI through PM10, the effect was not significant.
<p>Tidal swamp land is a potential area for rice cultivation. However, tidal swamp is fragile ecosystems, so that when this area is used for rice cultivation, it has to be done carefully. To reduce a risk of environmental pollution in the tidal swamp area due to rice cultivation, the area should be managed properly and wisely especially when using agrochemicals such as fertilizers and pesticides. In relation to this, the use of bio-fertilizer such as Azotobacter or/and Azospirillum, an atmospheric nitrogen fixing bacterium, might be an important thing for this area. The objectives of this study were to evaluate the number of NFB (i.e. Azotobacter and Azospirillum spp.) found in tidalswamp rice fields of South Kalimantan, and their ability in fixing atmospheric nitrogen and supplying this fixed nitrogen to rice, and in increasing rice yields. There were three research stages performed in this study. The first, collecting, isolating and purifying the NFB on the selective media of nitrogen free media. The second, a hydroponic experiment in the greenhouse using Yoshida nutrition solution (Yoshida et al., 1976 in IRRI, 2003) as culture media and selected Azotobacter and Azospirillum. The third experiment was to study the effect of selected Azotobacter isolates to increase growth and yield of IR64 and Margasari rice cultivars, and two Azotobacter isolates were combined with six inoculation methods for Siam Unus rice cultivar as treatments. The result showed that the number of NFB strains found in rhizospere rice cultivars were varied widely. Then, Azotobacter and Azospirillum spp selected from rice fields in the tidal land of South Kalimantan when associated with IR64 and Siam Unus rice cultivars have ability in fixing atmospheric N2 and in supplying N on the initial rice growth. Azotobacter T.B.PDST.2b and T.HM.BPMT.2b were significantly supplying N for early growth of IR64 rice cultivars (2.34 and 2.13 %N). The ability of these isolates to fix atmospheric N2 was similar to N fertilizer (urea) in supplying N (2.2% N). Only Azotobacter T.B.PDST.2b was relatively significant to supply N (1.36% N) for Siam Unus rice cultivar early growth, even though this strain has less ability than N fertilizer (1.94% N) in supplying N. Azotobacter isolates grow in media containing no urea were higher IAA produced than in media containing Urea. Furthermore, yield of IR64, Margasari and Siam Unus inoculated with Azotobacter isolates were 3.87–4.93; 4.63-5.36 and 5.44-6.42 ton/ha respectively. In conclusion, the utilization of Azotobacter and Azorpirillum spp to substitute N fertilizer would be able to increase effeciency of N nutritions and to avoid environment pollutions risks from agrochemical N fertilizer other than to increase rice yields on tidal land of South Kalimantan.<br />Keywords: Azotobacter, Azospirillum, rice cultivars, tidal lands and rice yields.</p>
Peatlands with very high C contents are generally considered a source of greenhouse gas (GHG) emissions. This research aimed to quantify the changes in peatland characteristics and GHG emission from the conversion of peatlands to agricultural areas. Height of water table, pH, electrical conductivity (EC), redox potential (Eh), organic carbon (OC), hot water-soluble C, total-N, the concentrations of NH4 +, and NO3 −, soluble-Al, soluble- Fe, and the emission of CH4, CO2 and N2O were quantified before and after land clearing of peats for agriculture. Results of study showed that pH, EC, OC contents, hot water-soluble-C, and total-N did not change after peatland clearing for agriculture. On the other hand, the concentrations of NH4 +, NO3 −, soluble-Al, soluble-Fe, redox potential and height of water table increased significantly after the peatland land clearing. Methane emissions from peatlands before peatland clearing were in the range of 0.13-0.22 mg C m−2 h−1 increased significantly to 0.14-0.31 mg C m−2 h−1 after the peatland clearing. The land clearing of peatlands for agricultural practices also caused increases in CO2 and NOx emissions by 85% and 76%, respectively. Changes in GGH emissions were not related to the changes in substrates quality of peats (OC contents, total-N and hot water- soluble-C). Results of the study indicate that increases in the GHG emission following the use of peatlands for agricultural areas are attributed to the changes in the peat characteristics.
Cellulase enzyme consists of three extracellular enzymes that work synergistically to degrade cellulose, namely endoglucanase, exoglucanase and β-glucosidase. These enzymes play a role in transforming insoluble polymers into soluble glucose. The aim of this researh were to isolate and purify cellulolytic microbes from tidal rice fields of South Kalimantan and know cellulolytic enzyme activity based on typology of tidal land. Ability of microbes to excrete endoglucanase enzymes based on cellulolytic index value in CMC media and the ability of microbes to excrete exoglucanase and β-glucosidase enzymes were measured using a modified method of Mandel. The results showed that the range of index values of microbial cellulolytic isolated from type A in tidal rice fields was 2.
This study aims to know the factors that cause the formation of Acid Mine Water, to analyze the methods of prevention of acid mine drainage has been running effectively, to analyze how to prevent the formation of acid mine water at the research area. This research was conducted atLemovillage,North Barito Regency. These results indicate the analysis of water quality in the company with an indication acidic low pH values and high metal values. It is supported by soil pH test results showed low pH, especially on the layer in direct contact or close to coal. Sources of acid mine drainage at the company are from the oxidation of water and oxygen on the wall of rock at pit, water from the dumping area, water flowing from the temporary stockpile into the settling pond 2. From these, we can conclude the results. Recommendations prevention of acid mine drainage can be done by moving the location of the temporary stockpile in accordance with, more effective functioning of sump, controlling the movement of acidic water that has formed, accommodate and neutralize the acidic water that has formed, forming a layer of dry cover, separating the flow of water is not acidic and acidic
The utilization of peatlands may decline the ecological functions of peatlands as carbon sink, water storage and biodiversity source. Therefore, different scientific approaches are required to increase peat productivity and inhibit decline in the ecological functions of peatlands. This article is aimed to provide information on researches that have been carried out in tropical peats in the South Kalimantan Province. The exploration and the potential utilization of microbes was reviewed from several studies conducted in the Desa Landasan Ulin Utara (LaURa), Kota Banjarbaru, South Kalimantan Province. Peat research carried out in the Desa LaURa during the dry season after peat fires in 2015 showed that microbial SRBM (mixture of N fixing, solubilizing P and cellulolytic microorganisms) from the modified recharge bio-pore system was able to improve the growth of roots, stems, and leaves, nutrient uptake, and increase production and biomass of soybean. In another research in 2018, the use of commercial biofertilizers containing Azotobacter sp and Lactobacillus sp applied to the LaURa peats significantly increased the total N and pH of peats but did not accelerate the decomposition of peat materials. In subsequent study on the exploration of nitrogen fixing microorganisms from the LaURa peats (sapric peats) which amounted to 10375-10500 cells g−1, the total N-fixing microbial population was correlated positively to the pH and EC of peats, and correlated negatively to the contents of peat organic C. Combining the results, the total N2 fixing microbial (NFM) population was significantly affected by organic C and peat EC (total NFM population = -154.052 + 33.126 pH + 607.117 EC, R2 = 51.63%). Results obtained from these studies demonstrated that the functional microbes of peatlands are able to maintain ecological functions of the peats.
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