Corg Content Research Articles

Suitability of Nutmeg Plant Habitats in Three Nutmeg Production Centers using the Geographic Information System and Aster DEM in West Java, Indonesia

Nutmeg plant (Myristica sp.) produces seeds and mace as the main commodities of world spice trade. Nutmeg plant habitats in West Java are distributed mainly in Bogor, Sukabumi and Cianjur Regencies. This study aimed to determine the suitability of nutmeg habitats in three nutmeg production centers in West Java based on soil type and slope using the Geographic Information System (GIS) approach and Aster DEM (Digital Elevation Model) analysis. The study was conducted from August to December 2018, by collecting data of: a) The coordinates of the area planted with nutmeg using GPS (Global Positioning System), b) Field documentation in the form of descriptions around the data collection point, c) Soil analysis data, d) Land area data, e) Map of the earth scale of 1:50,000 scale from the Geospatial Information Agency, and f) Landsystem map of West Java scale of 1:250,000. Data were analyzed using Arc GIS 9.3. The results of land suitability analysis based on rainfall data for Bogor region was classified in the category of marginally suitable (S3), while the regions of Sukabumi and Cianjur were sufficiently suitable (S2). Temperature of Bogor region was categorized as the most suitable (S1), while Sukabumi and Cianjur regions were sufficiently suitable (S2) for nutmeg development. The distribution of nutmeg was in Latosol and Regosol soils, with soil pH of rather acidic (pH 4.78-5.98), clay texture, low to high C-organic content (1.5-4.5%) and moderate to high N-Total (0.2-0.5%). Cation exchange capacity ranged from 25-30 cmol(+)/kg with a base saturation level of around 55-60%. Based on slope, the distribution of nutmeg in the West Java region was in the range of slope with a flat (<8%) to sloping (8-15%) category, with altitudes between 400-900 m above sea level classified as suitable to very suitable for nutmeg development. The overall agroecological suitability of nutmeg plants in three nutmeg production centers in the West Java region was classified as suitable to be managed and developed.

Kesuburan Tanah dan Produktivitas Padi pada Budidaya Organik, Semi Organik, dan Konvensional di Kabupaten Sragen

<p>The farmers realize that Green Revolution technology with external inputs (mineral fertilizer and pesticide) is no longer sustainable and cost production become too expensive. The farmers want to move to organic, semi organic and some remain doing conventional farming system. The aim of the research was to study the dynamic of soil fertilities and biomass production under organic, semi organic and conventional rice farming systems. The study was conducted in Termes Village Sambung Macan Sub District, Sragen District, Central Java and Analytical Laboratory of the Yogyakarta Assessment Institute for Agricultural Technology from March 2017 to 2018. Soil composites were taken in March 2017 and in 2018 at organic, semi organic and conventional rice farming systems. The results showed that in general the soil chemical fertility taken in 2018 under three rice farming were better than soil sampled in 2017 including pH, C organic, N total, P and K extracted with HCl 25 %. The same results were happened in rice biomass production, in organic rice farming was more excellent compared to semi organic and conventional rice farming and in semi organic was better than conventional rice farming because of soil C-organic content were higher.</p>

Features of the microcomponent composition of pore solutions of rocks of the Bazhenov Formation in Western Siberia

The results of experimental studies of the macro- and microcomponent composition of pore solutions of bituminous clay-siliceous rocks of the Bazhenov Formation (BS) of Western Siberia, containing up to 12.63% Corg (“normal rocks”), as well as silt-sandstones from the “anomalous” section are presented. BS with a Corg content of up to 0.63% (“abnormal” rocks) obtained on the basis of a study of aqueous extracts from core samples. It has been established that pore solutions of “normal” BS rocks have a sulfate-bicarbonate-sodium composition, and “abnormal” ones have a hydrocarbonate-sodium chloride composition. In pore solutions of both “normal and“ abnormal ”rocks relative to ocean water, the following were noted: a) concentration of Mn, Co, Ni, Cu, Zn, Mo, Sb, Cd, Ba, V, Cr of various degrees of intensity; b) increased content of Cs, Pb, Ti only in pore solutions of “abnormal” rocks; c) reduced content of Li, B, Rb, Sr. A direct relationship was found between the contents of Li, B, Ba, Sr, U, Mo, Cd, Sb, and Ni with the content in the Corg rock. For V, Cs, Sb, Rb, Ti, Mn in pore waters, the relationship with the amount of Corg in the rocks is close to the inverse relationship. In the pore solutions of “normal” BS rocks, the Ba content is equal to or higher than the Sr content, which is anomalous with respect to the stratal waters of most oil fields and ocean water and, apparently, is associated with the peculiarities of the accumulation of organic clay deposits, since in “anomalous” rocks The BS content of Sr is two times higher than the Ba content, which is closer to the usual for most natural waters.

Organic Carbon Origin, Benthic Faunal Consumption, and Burial in Sediments of Northern Atlantic and Arctic Fjords (60–81°N)

AbstractFjords have been recently recognized as hot spots of organic carbon (Corg) sequestration in marine sediments. This study aims to identify regional and local drivers of variability of Corg burial in north Atlantic and Arctic fjords. We provide a comparative quantification of Corg, δ13C, photosynthetic pigments content, benthic biomass, consumption, Corg accumulation, and burial rates in sediments in six fjords (60–81°N). Higher sediment Corg content in southern Norway reflected longer phytoplankton growth season and higher productivity. Higher contributions of terrestrial Corg were noted in temperate/southern Norway (dense land vegetation and high precipitation) and Arctic/Svalbard (glacial erosion) than in subarctic/northern Norway locations. Benthic biomass and carbon consumption were best correlated to δ13C and photosynthetic pigments content indicating control by quality rather than quantity of available food. Benthic faunal consumption did not seem to affect the variability in Corg burial. Regional environmental factors (water temperature and latitude) combined with local factors (Corg, grain size, and pigment concentration) explained 94% of Corg burial variability. Based on the present study and literature data on Corg content, origin, and burial rates, the fjords were classified into four categories: temperate, subarctic, Arctic with glaciers, and Arctic without glaciers. The variability in marine productivity, terrestrial inflows, and carbon sequestration in fjords must be considered for global estimates of their role in blue carbon storage and for building scenarios of future changes in the course of climate warming.

Soil aggregate-related organic carbon and relevant enzyme activities as affected by tea (Camellia sinensis L.) planting age in hilly region of southern Guangxi, China

It is essential to reveal the variations in the activities of carbon (C)-cycling enzymes in soil aggregates of different sizes, so as to shed more light on the soil organic C (Corg) dynamics in the tea plantation ecosystems. In this study, the activities of cellobiohydrolase, xylanase, β-glucosidase, and invertase were detected in soil aggregates obtained at the depth of 0–20 cm from tea plantations of various ages (8, 17, 25, and 43-yr.) in hilly region of southern Guangxi, China. Soil aggregates were divided into >2, 2–1, 1–0.25, and <0.25 mm fractions through a dry sieving procedure. This study hypothesized that the potential of soil Corg decomposition would be higher at early stage (in the initial 17-yr.) than that at late stage (after 17-yr.). Our results suggested that, irrespective of the tea planting age, soil aggregate-related Corg contents were mainly distributed in the >2 and 2–1 mm fractions, and soil aggregates at the >2 mm sizes had the highest activities of C-cycling enzymes. Notably, the C-cycling enzyme activities in soil aggregates were closely correlated with Corg availability, and Corg contents might not exert a vital part. On the other hand, tea planting for a long time could promote soil Corg to be accumulated. At early stage, the accumulated soil Corg was primarily derived from the >2 mm fractions; meanwhile, the C-cycling enzyme activities in the >2 mm fractions were also markedly elevated, indicating that the accumulated Corg in soils at early stage was more easily decomposed and showed a higher potential of decomposition than that at late stage, thus supporting our hypothesis. Overall, the youthful tea plantations in the initial 17-yr. showed an increasing trend with respect to the potential of soil Corg decomposition; however, when tea plantations became mature, the potential of soil Corg decomposition was reduced in hilly region of southern Guangxi, China.

Geochemical Studies of Cenozoic Shale Beds of the Western Cis-Caucasian Region

Geochemical parameters of the Cenozoic shale strata of the western Ciscaucasia have been analyzed. Oil source strata were identified in the study. The geochemical characteristics of organic matter (OM) of the Kumian rocks revealed high oil source potential of the rocks. The formation and emigration of hydrocarbons (HCs) were inferred from qualitative and quantitative changes. Sapropelic OM generated large amounts of hydrocarbons in the Kuma Sequence, with the value increasing from the top to the bottom of the profile. Para-autochthonous and migratory bitumoids were registered on the PC3 gradation and well-developed on the MK2 gradation (at a depth of 4.6–5.0 km). A comprehensive study of OM from Khadumian rocks by pyrolysis, bituminology, and chromatography showed that all kerogen types were developed in the rocks, but mixed OM with moderate oil source potential predominated. Maximal organic carbon (Corg) concentrations and genetic potential were observed within the Western Kuban trough, as well as in the strip of outcrops in the Adygei ledge area. The improvement in geochemical parameters in these areas is due to a decrease in the terrigenous component in the crude OM in the same direction.

KARAKTERISTIK STRUKTUR DAN SIFAT KIMIA PRODUK BIOGENIK RAYAP SCHEDORHINOTERMES SPP DARI CAMPURAN LIMBAH KERTAS KORAN DENGAN LIMBAH PENGOLAHAN TAHU

Biological activity of termites consistently generates various biogenic products depend of the type of food sources. Furthermore, the biogenic product is believed to have an important role in the improvement of soil physical and chemical properties. The purpose of this study is to determine the structure and chemical properties of biogenic products resulted from the activity of termites Schedorhinotermes spp. using newsprint paper and tofu processing wastes as food sources. Newsprint paper waste was mixed with tofu processing wastes water at a different levels, i.e. 10 %, 20 %, and 30 % (w/v) for the objective of study. Each of the mixture with weight of 18,8 g equivalent to oven dry weight was then placed in the sample container unit size 6 x 6 cm, placed at about 3 cm underground with the indicated of termite Schedorhinotermes spp activity, and covered by PVC stopper. The testing unit were left in place for about 6 weeks to allow the termite attacks. The attacked sample unit were then analyzed for their structure and chemical properties including bulk density, aggregate fraction distribution, pH, C-organic content. The soil around the sample unit were took using a 7 cm diameter ground ring to be used as a reference or comparison with biogenic structures formed by termites. The result showed that the biogenic products have better structure and chemical compared to the its surrounding soil.

Valorization of extracted organic matter from municipal solid waste leachate: Application to soils from France and Togo

Hydrophobic like (HPO*) and transphilic like (TPH*) fractions of organic matter (OM) were extracted from municipal solid waste leachate (MSWL) to assess their opportunity of valorization as organic amendments. Two soils with different carbon organic (Corg) content were studied: a soil from Togo (Corg = 0.3% in top horizon) and a soil from France (Corg = 4.2% in top horizon). HPO* and TPH* fractions were characterized by combining elemental analysis, determination of specific ultra-violet absorbance (SUVA) index and distribution of apparent molecular weight (AMW). Comparison to natural organic matter (NOM) fractions from surface water confirmed high similarities in composition except a lower oxygen percentage explained by the different genesis processes. HPO* and TPH* adsorption tests were conducted under batch experiments on each horizon of both soils to evaluate the impact of OM fractions on the physico-chemical characteristics of soils, to determine the carbon adsorption and to calculate their adsorption capacity. Whatever the soil, Corg adsorption did not correlate with clay content but rather with initial Corg content in the horizon. HPO* fraction was better adsorbed than TPH* fraction. Besides, while Corg adsorption percentages on each horizon of soils were higher for French soil, the adsorption capacities, explained as the ratio of organic carbon mass adsorbed on soils on its initial carbon mass, were 2 to 10 times higher for soil from Togo.

THE STATUS OF SOIL PHOSPHORUS AT DIFFERENT CROPPING SYSTEM IN PANGALENGAN, SOUTH BANDUNG

The fixation of P in soils is dynamic in nature and the behavior of P-fraction may change with time and cropping system. Application of organic matter to soil under upland soil have been reported to decrease P-sorption and increase P-desorpion. Pangalengan, South Bandung in west Java is one of the wet humid area of Indonesia that has high rain fall, covered mainly by tropical humid forest, volcanic area with fertile volcanic soil. The objective of this study were to describe and compare some chemical characteristic and behavior of P-fraction as a function of crops and slope of the land in the farming system in Pangalengan, South Bandung, West Java, Indonesia. Soil samples from the surface soil (0-20 cm) were collected from 15 locations based on different planted crops (Tea, Vegetables, Forest, and Intercropping crops), and level of slope of the land areas of Cihawuk village, District Kertasari, Kecamatan Pangalengan. The result of the study showed that C-organic content of soil samples from 15 location of planted crops was slightly high (3.04-4.92 %) but total Nitrogen was low (0.22-0.45 %), wih soil reaction (pH H2O) was slightly acids (5.60-6.30) and pH (KCl) was lower than pH(H2O) (4.60-5.70). The available-P was low (3.50 – 7.10 ppm), but the HCl 25 % P from tea and vegetables location was higher than from forest and intercropping crops. Majority of P fraction from tea and vegetable location was Al-P fraction, but from Forest and intercropping crops was Ca-P fraction. The order of P fraction were Al-P &gt; Ca-P&gt; reductant soluble-P&gt;Fe-P in tea and vegetables locations, but in the forest and intercropping were Ca-P&gt; reductant-P &gt; Al-P &gt; Fe-P. However, The data showed that the total P (P-organic + P-inorganic) from tea and vegetables crop location was higher, and was dominated by inorganic form, than from forest and intercropping location was dominated by organic form. However, the slope did not affect the pattern of P-fractions and the sources of organic matter added or accumulated in those location formerly affected the amount and the pattern of P-fractions.

Penyebaran Dan Karakteristik Habitat Jenis Rasamal (Altingia excelsa Noronha) di Taman Nasional Gunung Halimun Salak

Rasamala ( Altingia excelsa Noronha ) is one of the primary species in Halimun Salak Mountain National Park that grows in the lower mountain forests. In addition to the value of conservation, almost all parts of rasamala species can be utilized such as wood, leaves, fruit, and the canopy as a bird habitat. Information of natural distribution and habitat of rasamala are needed for conservation and cultivation purposes. The objectives of this research are to identify the distribution pattern and habitat characteristics of rasamala in Halimun Salak Mountain National Park. Research was done by make square plots with 30x30 m2 size that spread in the area of Halimun Montain 15 plots and Salak Mountain 15 plots. The analysis used morisita index to know the distribution pattern of rasamala and linear regression analysis to determine the influence of environmental factors. The result showed that distribution pattern of rasamala was clumped. Environmental factors that affect the existence of rasamala encompass altitude above sea level, slope, temperature, humidity, soil C-organic content, and N-total where the most influential factor is the N-total content of the soil. F test results on regression showed that the variables tested in Resort Cikaniki simultaneously had no significant effect on rasamala density, while the variables tested at Kawah Ratu Resort had significant effect on rasamala density

Soil physicochemical properties in oil palm plantations impacted to peatland fire

Currently, Indonesia has 1.7 million hectares of oil palm plantations on peatland (12% of the total area of 13.5 million ha Indonesia’s peatland). As a consequence, fires on peatland become trending topics. Field observation research that aims to determine the physical and chemical characteristics of peat in oil palm plantations has been carried out on several peat locations in West Aceh District: Suakraya village, Johan Pahlawan district (15 years old), Cot Gajah Mati Village, Arongan Lambalek district (1 year old), and Suakpuntong village, Nagan Raya district (10 years old). Substantial changes in the physicochemical properties of soils from oil palm plantations were observed, then evaluated the impact these characteristics to fires on peatland. The analysis soil showed that peatlands around in West Aceh District have physical characteristic: bulk density (BD) from 0, 12 - 0.16 g cm-3; groundwater level of 6 cm (rainy seasons) and 86 cm (dry seasons); moisture or water content in the surface layer (0-20 cm) during the dry season was 505 - 985% The thickness of peat was 457 cm on deep peat in Suakraya, 157 cm on shallow peat in Suakraya, 243 cm in Cot Gajah Mati, 136 cm in Suakpuntong. The chemical characteristic of peat soil has pH H2O 2.9 – 3.9, pH KCl 2.23 - 3.07. The level of maturity of peat in the surface layer in all observation locations is the same, namely hemic. Water content per unit dry weight depends on peatland maturity level (fibric: 540 - 1187%, hemic: 268 - 480% and sapric: 106 - 242%). Ash content per unit dry weight varied from 1.8 – 5.9%, and C-organic content 53.4 – 57.6%. Peat total acidity is 4.2 – 6.4 me g-1, COOH content 0.02 - 0.16 me g-1 and phenolic-OH content 4.2 – 6.2 me g-1. The important result of this study showed that the causes of peatland fires are not caused by the characteristics of peat (occur naturally), but there are triggers of human activities.

The study of Aluminum (Al) fractionation on forest land, agroforestry, and dryland agriculture in west java

The aims of this study were to evaluate the distribution of Aluminum fraction (Al) on the horizon of forest land, agroforestry, and dryland agriculture in West Java highland soils and looking correlation with soil chemical fertility, is pH, CEC, organic-C, total N, total P, available P and soil texture. The evaluation was carried out on the results of the analysis of soil samples taken at four soil horizons (Ao or Ap, A1 or A2, B1, and B2) in each land use. Al fractionation using extraction methods with different chemicals to find exchangeable Al (Alex), amorphous Al (Alo), amorphous Al organic (Alp), amorphous Al bound weakly to organically (Alcu), Amorphous Al bound strongly to organic (Alop), and amorphous Al inorganic (Alpcu). The results showed that the Alo fraction dominated the other Al fractions in each land use. In forest land Alo fraction (> 58.61%) with a fluctuating distribution pattern, in agroforestry (54.45%) with a declining distribution at the depth of the soil horizon, then on dryland agriculture (> 89.86%) it increases fluctuatively with the depth of the soil horizon. The addition of organic material/compost must be done to increase the organic-C content in the soil.

Lignite-based Organic Fertilizer Improves Soil Quality and Yield of Rice in Belitang South Sumatera

To achieve food-self sufficiency in Indonesia, it is necessary to apply sustainable agriculture practices to improve soil quality. Most of paddy fields have been applied with chemical fertilizers intensively for more than 40 years without the addition of organic matter. The purpose of this study was to understand the effects of lignite-based organic fertilizer application on the quality of paddy soil and yield of rice. The study was conducted in April until August 2014 in the irrigated rice fields in Belitang, Ogan Komering Ulu Timur District. The study was arranged in a Factorial Randomized Block Design, with 9 treatment combinations and 3 replicates. The first factor was the types of fertilizers, consisting of recommended chemical fertilizers (250 kg urea ha-1 + 150 kg SP36 ha-1 + 50 kg KCl ha-1), organic fertilizer from plant residue at 5 Mg ha-1, and lignite-based organic fertilizer (namely Baranik fertilizer) at 0.75 Mg ha-1. The second factor was rice varieties, consisting of Mentik Wangi, Gogo Aromatik and Ciliwung. The application of Baranik fertilizer at 0.75 Mg ha-1 has improved the quality of paddy soil with the increase of organic-C content from 1.44% to 2.90%. Application of Baranik fertilizer at 0.75 Mg ha-1 has increased the vegetative components and the yield of rice about 7.17 Mg ha-1 compared to the organic fertilizer from plant residue, but the yield is still the same as that in the recomended dosages of chemical fertilizers. Among the rice varieties, the yield of Ciliwung variety was higher than other varieties, i.e. 7.62 Mg ha-1. The yield of Gogo Aromatik variety is significantly lower than that of Ciliwung variety. Baranik organic fertilizer can be used to improve soil fertility for food security purpose.

Preparation of Chitosan-EDTA hydrogel as soil conditioner for soybean plant (Glycine max)

Research on preparation of chitosan hydrogel cross linked with Ethylenediaminetetraacetic acid (EDTA) as soil conditioner for soybean (Glycine max L.) plants was successfully carried out. The aims of study are to determine the characteristics and effect of composition comparisons in preparation of hydrogels and to determine the physicochemical properties of soil such as humidity, temperature, pH, absorbed potassium levels, C-organic content and cation exchange capacity. The characterization was carried out using FTIR and SEM. FTIR analysis showed specific the presence of functional groups, O-H (3450.65), CH3 (2924.09), COOH (1382.96), N-H2 (1587.42), and CO amide (1635.64). SEM analysis shows the hydrogel surface in each composition and concentration of chitosan-EDTA of different pore or cavity sizes so that it influences the degree of swelling and crosslinking degree. The application of chitosan-EDTA hydrogel for the improvement of soybean plants with a composition of CHITA225 can have a significant influences on the 75th day of measurement. The soil pH values between 7.6 and 7.9, humidity of 31%, soil temperature of around 26–29 °C, absorbed potassium levels of 11.29 ppm, soil organic content of 2.56%, and cation exchange capacity of 17.22 meq/100 g. In addition, the effect of hydrogel use on soybean plants shows the maximum number of leaves measured at 60 days, 98.2 cm and 25 strands. The results showed that the hydrogel synthesized by chitosan and EDTA has the potential as soil conditioner.

Effect of green alder (Alnus viridis) and black alder (Alnus glutinosa) on chemical and microbial properties of sandy mine soils

Various alder species may be used in the reforestation of post-mining barrens in order to supply developing mine soils with nitrogen, increase their organic matter content and biological activity. The objective of this study was to compare the effect of green alder (Alnus viridis) and black alder (Alnus glutinosa) on chemical and microbiological properties of sandy mine soils. The samples of O horizon and mineral soil (0–5 cm) were taken under the equal-aged green and black alder stands growing on extremely poor sands and measured for the contents of organic C (Corg) and total contents of N (Nt), P (Pt), K, Ca and Mg. In the mineral soil, additionally available and water soluble P (Pavl and PH2O) was measured. The measured microbial properties included microbial biomass (Cmic), basal respiration rate (RESP), N mineralization rate (Nmineralization) and the activities of urease (URE), alkaline and acid phosphatase (PHOalk and PHOacd, respectively). The O horizon under black alder contained significantly more nutrients (Nt, Pt, K), harbored higher microbial biomass and exhibited higher basal respiration rate than the O horizon under green alder. In the mineral soil differences between the two alder species were less pronounced. The contents of Corg, Nt, Pt, K and Ca were similar under both alder species. The Cmic and RESP values also did not differ between the alder species. Nevertheless, higher Nmineralization, PHOacd and PH2O content under black alder suggest that this species increases N and P availability in the mine soils to a greater extent than green alder. We conclude that although both alder species contribute to development of mine soils the positive influence of green alder is less compared with black alder.

Multivariate Statistical Characterisation of Soil Quality in the Lower Danube River Riparian Areas

Increasing anthropogenic influences on the environment has caused negative changes in natural ecosystems and soil contamination with potentially toxic metals has become a worrying issue at global level, due to the negative impact on the environment and human health. For the purpose of assessing soil contamination in the riparian areas of the Lower Danube River, a number of 144 soil samples were collected twice a year, in the period of June 2013 � December 2016, from 9 monitoring locations, from 0.05 m and 0.3 m depths, and the following indicators: Cr, Cu, Mn, Ni, Pb, Zn, including Ca, Mg, Corg, SO42- and humus content have been monitored. The soil was sampled, conserved and analysed according to the European standards in force. Metal concentrations were determined using flame (FAAS) and graphite furnace (GFAAS) atomic absorption spectrometry after �aqua regia� digestion of dried, homogenised and 0.5 mm sieved soil sub-samples. Comparing the average concentration values of the analysed potentially toxic metals, a decreasing tendency following the order Cr]Pb]Ni]Cu]Zn]Mn was observed and by reporting the average values at the normal limits, the order Zn]Cu]Mn]Ni]Pb]Cr of magnitude was obtained. To investigate possible correlations and interdependencies of potentially toxic metals content in the riparian soil, multivariate statistical methods were used. After applying Principal Component Analysis (PCA), 3 main components were identified, with a combined share of about 74 % of the original data-set variance. It was observed that during the monitoring period the average values of the all monitored elements from the studied soils were slightly below the normal reference values, according to the national legislation.

Comparison of the Properties of Humic Acids Extracted from Soils by Alkali in the Presence and Absence of Oxygen

Humic acids (HAs) make up to 30–50% of the soil organic matter, which is the main reservoir of organic carbon in the biosphere. The common isolation protocol for HAs implies alkaline extraction from soils followed by acidification of the extract with HCl to pH 2. International Humic Substances Society (IHSS) recommends isolation of HAs in oxygen-free atmosphere (e.g., under nitrogen or inert gas purging) to prevent oxidative transformations of HAs during the extraction process. In the Russian school of soil science, extraction is usually conducted without the use of nitrogen. In the present work, we compared the physicochemical properties of HAs isolated from A1 horizons of soddy-podzolic soil (Retisol) and chernozem (Chernozem) by 0.1 M NaOH in the presence and absence of oxygen. The soils used in this study represented zonal types of southern taiga and steppe, respectively, and differed markedly with respect to humus formation conditions. The yield of humic substances (Corg content in the extracts), their elemental composition, functional groups content, molecular-weight distributions (gel filtration on Sephadex G-75), paramagnetic properties, and absorption spectra in the visible, UV, and IR regions were studied. For both soils, no statistically significant differences were found in the quantitative yield, molecular weight distribution, absorption spectra in the visible, UV and IR regions between HAs isolated by alkaline extraction in the presence and absence of oxygen. At the same time, for the HAs extracted from the Retisol soil in the presence of oxygen, higher O : C ratios, higher contents of quinone and carboxyl groups, and significantly higher content of free radicals were observed. This was revealed with the use of elemental analysis, potentiometric titration, 1H and 13C NMR spectroscopy, and electron paramagnetic resonance spectroscopy. For the Chernozem HAs, these differences were not observed. The obtained results suggest that partial oxidation of the soil organic matter components takes place during alkaline extraction from the Retisol in the presence of oxygen. In the Chernozem, humification process is apparently accompanied by significant oxidative transformation of organic residues, so the presence of molecular oxygen does not cause further oxidation of HAs under alkaline conditions. Our results indicate that, for the isolation of HAs from the mineral horizons of Chernozems, the use of oxygen-free atmosphere is optional. In the case of Retisols, the use of oxygen-free atmosphere is desirable, especially if it is intended to study the reactions of HA oxidation upon, for example, enzymatic catalysis.

Rekomendasi Pemupukan Padi Sawah (Oryza sativa L.) Spesifik Lokasi di Kecamatan Malinau - Kabupaten Malinau

The area of paddy fields in Malinau Kota District is around 463 ha or 10.29 percent of the productive paddy in Malinau Regency which reaches 4,500 ha. The productivity of rice in the area is still low, which is around 3-4 ton ha-1, its caused by the use of fertilizers that are not yet suitable for plant growth requirement. Therefore, in order to improve rice productivity, it is necessary to do soil analysis to formulate spesific location fertilizer recommendations based on soil nutrient status. The assessment was carried out in Malinau District, Malinau Regency, on September-November 2017. The purpose of the asseement was to develop recommendations for fertilizing specific location lowland rice based on soil nutrient status. The assessment method is to take composite soil samples from several representative locations, then analyze in the laboratory, and the results of the analysis are used to formulate recommendations for specific location lowland rice fertilization. The results of soil analysis showed that soil pH was acid, organic C-content was low, N-tot was low, P was medium and K was medium. Recommendations of N fertilization with Urea as the basic fertilizer 50-100 kg ha-1 and subsequent N fertilization based on leaf color chart (LCC), P fertilization with SP-36 as much as 100 kg ha-1, and K fertilization with KCl as much as 50 kg ha-1.

PENGOLAHAN LIMBAH BATANG SAWIT MENJADI PUPUK KOMPOS DENGAN MENGGUNAKAN DEKOMPOSER MIKROORGANISME LOKAL (MOL) BONGGOL PISANG

One of the main problem in palm plantations during the rejuvenations is the utilization of palm oil waste especially the palm trunks that reaching 220 m3/hectare. Based on that reason, we need a method of utilizing it that can increase the value from palm oil waste, not just for the benefits of oil palm farmers but also for the environment. Palm oil waste has the potential to become the raw material for making organic fertilizer (compost), it has a high nutrient content and can improve the quality of the fertilizer produced. The objective of this research was to produce a bio-fertilizer with a high quality based on the proper standards. This research was conducted in two stages including the produce of local microorganism (MOL) from banana stem and the composting stage. The composition of local microorganism materials was banana stem: cattle urine: coconut water: brown sugar with the raio of 2: 1: 1: 1. The composting stage was started after all materials were chopped and stirred together before it composted for one month by varying between the main materials and additional ingredients. The compositions of the palm trunks as the main ingredient were divided in five variations, i.e. 3, 6, 9, 12, and 15% (w/w/), this variations were composted together with two types of additional ingredients of POME and goat manure. Based on the results of the compost analysis, the best composition was the variables of palm trunks: pome: rice husk: ash = 3: 10: 2: 1 with the results of analysis were water content of 16.30%, total NPK of 6.08% , c-organic content of 44.10% , the ratio C/N of 16.30 and pH of 8.16 and it had been fitted with bio-fertilizer standard (Permentan No. 70/Permentan/SR. 140/10/2011).Keywords: palm oil replantation, bio fertilizer, palm oil trunks, decomposer, local microorganism

PERTUMBUHAN STEK BIBIT KOPI DENGAN PERBEDAAN JUMLAH RUAS PADA MEDIA TANAH-KOMPOS

The purpose of this study was to determine the growth response of various segments of coffee cuttings in the soil-compost planting media. This research was conducted from January 2018 to April 2018 at the Green House Polytechnic LPP Yogyakarta with BP 288 coffee plant clones. The treatment used was one segment cuttings, two sections cuttings, three sections cuttings and four sections cuttings with variable number of leafes, leaf color, shoot stem diameter, shoot length and number of shoots. This research method uses a non-factorial Randomized Complete Block Design (RCBD) with further DMRT methods.Based on the results of the study, it was found that soil-compost showed C-organic content of 8.54%, N content of 0.23%, P content of 0.14% and K content of 0.21% and the best results of plant growth were on the cuttings treatment of one segment cuttings, two sections cuttings, three sections cuttings and unfavorable growth, namely in the treatment of cuttings four sections.Keyworsd: Coffee, Cuttings, Growth