Potassium Soil Test Calibration for Corn on Typic Hapludox Cigudeg

Soil testing calibration is a process to provide meaning of soil test value in term of crops response. Research on soil testing calibration for corn has been carried out on Typic Hapludox Cigudeg. The objectives were: 1) to determine critical point of soil test value of K, 2) to determine the application rate of K fertilizer recommendation. The split plot design was used with consisted five rate of K fertilization on three K soil status as the main plots. There were four K soil test methods assessed to determine the critical point value for corn. K availability was classified into three categories namely low, medium, and high class. The results revealed that critical value of four soil testing methods for low, medium, and high respectively were : HCl 25% (<14, 14-29, and >29 mg 100 g-1), NH4OAc pH 7(<84 ppm, 84-220 ppm, and >220 ppm), Morgan (<70 ppm, 70-180 ppm, and >180 ppm), and Mechlich I (<54 ppm, 54-135 ppm, and >135 ppm). K fertilization significantly affected to corn plant height in the low soil K status until the rate of 60 kg K ha-1 (116 kg KCl ha-1). Dry biomass significantly increased due to K fertilization on low, medium as well as high soil K status. K fertilization also improved corn grain production. The ears of corn could not develop without K fertilization. This was an evidence that K nutrient has an important role in enzyme activity and assimilate translocation. Even with low rate of K fertilization, corn has succeeded to form ears and kernels. In the low soil K status, K fertilization sharply increased dry grain, but in the medium soil K status the curve was gentler. Whereas in the high soil K status, K fertilization did not significantly affect the dry grain yield. The recommended application rate of K fertilizationfor corn on Typic Hapludox Cigudeg with low K status was 89 kg K ha-1 and in the medium status was 53 kg K ha-1. Whereas in the high soil K status, no K fertilization was needed

ANALISIS KEBERLANJUTAN USAHATANI HORTIKULTURA SAYURAN PADA LAHAN BERLERENG DI HULU DAS JENEBERANG, SULAWESI SELATAN

This study aimed to analyse the sustainability of vegetables horticultural farming on sloping land in the upstream Jeneberang watershed based on the index evaluation and the status of sustainability by Rap-farm method using Multidimensional Scaling (MDS).Results of ordination technique analysis Rap-farm method of MDS showed that index of vegetables horticultural farming sustainability ranged from 32.19-62.53. Dimension of ecological, economical, institutional, and technological included into sustainable enough category, while social dimension, included into less sustainable category in vegetables horticultural farming systems.Results of leverage Rap-farm analysis showed that from 43 attributes that were analyzed, there were 23 sensitive attributes that affected into the sustainability of vegetables horticultural farming systems in the upstream of Jeneberang watershed. &nbsp

Recommendation of Sustainable Landuse in Border Area East Kalimantan-Malaysia

Development problems of agriculture on border area require handling which more comprehensive and sustainable. Up to now, research results indicate that efforts has been done in handling various problems in agricultural sector, but still partial and is not be able to overcome complex problems. Therefore to overcome various development problems of agriculture on the border area need to be done in holisticaly, covers all aspect i.e. social, economics, ecology, and institution. Sebatik Island is one of state border area between Indonesia and Malaysia, located in Nunukan District, East Kalimantan Province. Up to now, cocoa is still the priority commodity, but its productivity is relatively low. Based on potency and constraint of land resources in Sebatik Island, sustainable recommendations to increase land productivity of cocoa i.e. (1) land and water conservation management, (2) using organic matter, (3) proportional fertilization, (4) using mulch, (5) integrated crop management, (6) integrated crop-livestock system, and (7) improvement of capacity of farmers institutio

Pengaruh Pemberian Sulfur dan Blotong terhadap Pertumbuhan dan Hasil Bawang Merah pada Tanah Inseptisol

Penelitian ini bertujuan mengetahui pengaruh sulfur dan blotong terhadap pertumbuhan dan hasil bawang merah di tanah inseptisol. Penelitian dilaksanakan di rumah kaca Kebun Percobaan Jeneponto pada bulan Januari sampai April 2000 dengan rancangan acak lengkap pola faktorial dua faktor dengan empat ulangan. Faktor pertama adalah sulfur yang terdiri atas enam taraf dan blotong sebagai faktor kedua yang terdiri atas tiga taraf. Hasil penelitian menunjukkan bahwa bobot kering tanaman umur satu bulan, bobot umbi saat panen, bobot umbi kering eskip, dan kelas umbi dipengaruhi secara nyata oleh sulfur, blotong, dan interaksinya. Sedangkan susut bobot umbi tidak dipengaruhi oleh sulfur, blotong, dan interaksinya. Pemberian 40 ppm sulfur dan 75 g/pot blotong menghasilkan umbi kering eskip dengan bobot tertinggi

The Role of Iron Oxide in the Characteristics of the Highly Weathered Soil

Iron oxide is generaly found in the clay mineral composition of highly weathered soil (low activity clay soil) like Oxisols. There is limited information about the role of iron oxide in Oxisols, on the other hand the information is very important when we want to make use of the Oxisols. This study was done to investigate the role of iron oxide in the soilcharacteristic especially CEC, pHo, available water, plasticity index, soil color and maximum phosphate absorption. Soil samples were taken based on Soil Survey Staffs (1991), from different kinds of highly weathered soil i e: Typic Hapludox, Plinthic Hapludox and Anionic Acrudox, each sample was taken from two locations. At each location sample was taken from three different site : upper, middle and lower slope. Chemical analysis was done to determin the level of Fe.d, Fe.o, Fe.p, CEC (NH4OAc 1 M), pHo, available water, atterberg index and maximum phosphate absorption, and soil characteristics that useful for soil classification. Data were analyzed using matrix correlation test, simple and multiple regression. Principle Component Analysis was used to solve when multicolinearity problem happen. Results show that the Anionic Acrudox has the highest content of Fe.d and Fe.o, varied from 12.03 – 12.27% and1.01 – 1.12% . Followed by Typic Hapludox varied from 9.52 – 10.57% and 0.31 – 0.46% respectively for Fe.d and Fe.o. The level of Fe.d and Fe.o for Plinthic Hapludox varied from 6.31 – 9.40% and 0.09 – 0.17%. The higher the iron oxide content the lower the cation exchange capasity and the higher of the pHo. Multi regression analysis results between CEC and some soil characteristics shows that Fe.d and Fe.o can indicate thehighest variability namely 35.8%. While correlation between pHo and Fe.o shows the highest correlation and highly significant (r² = 0.65).Iron oxide has highly effect on available water and plasticity index, the higher the iron oxide content, the higher is the available water and the lower the plastisity index. The higher the iron oxide content the higher is intensity of red color of the soil. And the higher the iron oxide content, the higher is the maximum phosphate absorption; this condition is disadvantageus for plants, because the phosphate is not available for plants

Estimation of the Potential Carbon Emission From Acrotelmic and Catotelmic Peats

Agricultural development on peatland in Indonesia has been constrained by the presence of environment issues in relation to the release of greenhouse gases (GHGs) particularly carbon dioxide (CO2) and methane (CH4) to the atmosphere. This study was aimed to predict the potential carbon emission based on carbon stocks in acrotelmic and catotelmic peats with the reference of groundwater level of peatland.  The results showed that groundwater levels have played an important  role  in  carbon  release, which  has  close  relationship  with  water  regime  of  the upper  layer  of  peats  that influenced by oxidative and reductive conditions of the land.  From the layer that having groundwater level fluctuations during the period from rainy to dry season (acrotelmic peat), the emissions were mostly dominated by CO2 release, while from permanent reductive-layer (catotelmic peat) was not detected.  The decrease of groundwater level from -49.6 to -109 cm has clearly influenced carbon emission.  From each decreasing 1.0 cm groundwater level, CO2 emission measured during the period of February - October 2013 was calculated to yield about 0.37 Mg ha-1 yr-1.Keywords: Acrotelmic and catotelmic peat, carbon emission, groundwater level [How to Cite: Siti N, S Sabiham, B Nugroho and Di Nursyamsi. 2014. Estimation of the Potential Carbon Emission from Acrotelmic and Catotelmic Peats. J Trop Soils 19(2): 91-99. Doi: 10.5400/jts.2014.19.2.91]  [Permalink/DOI: www.dx.doi.org/10.5400/jts.2014.19.2.91] &nbsp

Keselarasan Penyediaan Nitrogen dari Pupuk Hijau dan Urea dengan Pertumbuhan Jagung pada Inceptisol Darmaga

Increasing N use efficiency and decreasing N pollution can be achieved by synchronization between supplying pattern of N and crop N demand. Leaching-incubation experiment had been carried out for evaluating supplying pattern of N from 14 treatments of green manure (Flemingia and Gliricidia), urea and their combinations. Only 5 treatments of the split application of Gliricidia, urea and their combinations, and single application of combination of urea and Gliricidia synchronize with corn N uptake model. These five fertilization treatments were further examined in the greenhouse and in the field experiment. The synchronization between supplying pattern of N and corn growth in treatment without leaching was resulted by application of urea at planting followed by Gliricidia at 3 weeks after planting (WAP) and urea at planting and 3 WAP, whereas in treatment with leaching were resulted by split application of Gliricidia at planting and 3 WAP, urea at planting followed by Gliricidia at 3 WAP, and single application of urea and Gliricidia at planting. Urea applied at planting followed by Gliricidia at 3 WAP resulted in the high production of seed dry-weigh with low N inorganic leaching

Sustainability Analysis of Existing Agriculture on High Risk Erosion Area (Case Studies in Lembang, West Bandung District and in Dongko, Trenggalek District)

There are three main constraints for the upland agriculture development, namely (1) steep slopes that limit the suitable farm land, (2) soil erosion rate tends to be higher than the rate of soil losses and (3) high average annual rainfall. This research focused on sustainability analysis at high risk erosion area in Lembang sub district and Dongko sub district. The aim of this research was to analyze index and sustainability status of the border area, existing farming on high risk erosion. Multi Dimension Scalling-Rapid appraisal for farming (MDS-Rapfarm) technique was used for evaluating the sustainability of existing farming based on five sustainable indicators i.e. ecology, economy, social, local organization, and technology. Soil analysis and USLE method were used to predict erosion rate and soil fertility. The result of the MDS analysis showed that sustainable multi-dimension index (ecology, economy, social, local organization, technology) of Lembang sub district was 35,47; 38,15; 56,42; 34,49; 17,30;and Dongko sub district was 24,16; 47,13; 63,78; 64,78; 41,55 (on scale 0-100). The average of soil loss in Lembang was predicted 147,29 t ha-1 year-1 and in Dongko was 245,95 t ha-1 year-1 on average. Attributes being sensitive in increasing index and sustainability status were: source of organic matter, perennial proportion, farmer oriented on agriculture extension, social conflict intensity, annual rainfall, land solum, land conversion, and number of agriculture household