Amelioran Organik dan Mikoriza Meningkatkan Status Fosfat Tanah dan Hasil Jagung pada Tanah Andisol

. A common problem of Andisol soils is the high capacity for P adsorption, although total P content is relatively high. This characteristic causes inefficient use of P fertiliser, to the point that P deficiency can become a major constraint for crop production. This study aimed to determine the effect of organic ameliorants and mycorrhiza on the status of soil phosphate and yield of maize in Andisol. The experiment was carried out in pots and arranged in a randomized complete block design (RCBD) 4x2 factorial with 3 replications. The first factor is the addition of organic ameliorant consisting of 4 treatments: without ameliorant, manure, rice straw and Gliciridea leaves. The dosage of each ameliorant is 20 ton ha-1 or equivalent to 111 g per polybag. The second factor is the application of mycorrhiza, consisting of 2 levels, no mycorrhiza and mycorrhiza at 10 g per polybag. The results showed that the application of organic ameliorant and mycorrhiza affected soil pH, total P (HCl 25% extractable P), available P (Bray 1), and the P availability index and increased the growth and yield of maize in Andisol. The two treatments that provided the most effect on the status of soil phosphate and plant growth and yield of maize were manure, and Glyricidea leaves, in combination with the addition of mycorrhiza

Analysis of Soil Quality for Hydrological Disaster Mitigation in Sub-Watershed of Krueng Jreue, Aceh Besar Regency-Indonesia

Land conversion of forest to non-forest has led to a reduction in soil fertility, exhibited by a lower soil quality index value (SQI) in the Sub-Watershed of Krueng Jreue. This study aimed to determine soil quality associated with various land uses using the SQI value approach. SQI is calculated based on the criteria proposed by Mausbach & Seybold (1998), which is suitable for field conditions using analysis of Minimum Data Set (MDS). The parameters analyzed include rooting depth, soil texture, bulk density, total porosity, pH of the soil, C-organic, N-total, P-available, K-exchangeable and soil respiration. The result showed that the quality criteria of the soil in the study area consists of three classes, namely: low, medium and high, which have soil quality index values of 0.27, 0.52, and 0.64 respectively. Based on the study's soil quality criteria, the area of research was mapped accordingly by class: (1) high, covering an area of 14016.98 ha (60.38%); (2) medium, covering an area of 8542,90 ha (36.79%); and low, covering an area of 658,18 ha (2.83%). Types of land use categorized as having high quality, were primary forest, secondary forest and residential area with respective values of 0.66; 0.64, and 0.63. Open land, grassland, moor, rice field and shrubs were of medium quality, with respective values of 0.47; 0.48; 0.52; 0.51 and 0.55. The main and additional components affecting the hydrological disaster vulnerability on soil quality parameters are land use change, and soil properties. The findings of this research have implications structural efforts to mitigate hydrological disasters (dams, catchment wells, biopori, tillage conservation, terracing), and non-structural efforts (maps of soil quality, agroforestry, cover crops, materials of soil conditioner, organic matter). These efforts are necessary to improve and maintain soil quality longitudinally

Improving Soil Chemical Properties by NPK Fertilizer Application and Residual Rice Husk Biochar Effect on Irrigation Paddy Field

The research objective was to study effects of NPK fertilizer and biochar residue on soil chemical properties of paddy on second planting. Experiment was arranged in a randomized complete block design in a factorial design with four replications. Biochar consisted of two levels, i.e. without biochar residue and with biochar residue 10 ton ha-1. NPK fertilizer consisted of three levels, i.e. without NPK, NPK 60 kg ha-1, and NPK 120 kg ha-1. The result showed that application NPK fertilizer and biochar residue on second planting increase total N 22.22%, available P 12.18%, available K 17.50%, and organic C 56.69% compare than first plantin

ASSESSMENT OF DROUGHT INDICES AND WATER AVAILABILITY USING STATISTICAL Z-SCORE AND MOCK MODEL

The phenomenon of drought and water scarcity due to climate change is a major problem in many countries. Assessing drought conditions and water availability in a watershed helps the government and communities implement sustainable watershed management. The study was conducted in Krueng Jreue Sub Watershed, Krueng Aceh Watershed, Aceh Province, Indonesia. The meteorological and hydrological indices in the watershed were analyzed using statistical Z-Score for Precipitation (ZSP) and Discharges (ZSD). Discharges originated from Mock model was used to examine the water availability in a watershed. The results showed the ZSP and ZSD indices from 2008 to 2017 were almost categorized as normal. In certain months, drought indices with the criteria of extreme wet (EW), very wet (VW), and severe drought (SD) also occurred. In general, the ZSP and ZSD indices were consistent, but for certain months (April 2008, November 2010, and March 2017) inconsistencies were found due to differences in signs and index classes. The Mock model parameters for the proportion of surface soil uncovered by vegetation (m), infiltration factor (IF), initial soil moisture (ISM), and flow reduction coefficient (Rc) were 20 %, 0.4, 200 mm month-1, and 0.6, respectively. The average monthly discharge during the period of 2008-2017 ranged from 3.16-31.18 m3s-1. The total water needs of 5.041 m3 s-1 per month. The water availability per month was surplus in the rainy season (October-April), but deficit in the dry season (May-September). This research not only contributes to enriching references for similar research in Krueng Aceh Watershed, Indonesia but can also be applied to other watersheds according to the current conditions of watershed characteristics

Analysis of Soil Quality as Hydrological Disaster Mitigation Effort in Krueng Jreue Sub-Watershed, Great Aceh

Land conversion of forest to non-forest has led to a reduction in soil fertility, exhibited by a lower soil quality index value (SQI) in the Sub-Watershed of Krueng Jreue. This study aimed to determine soil quality associated with various land uses using the SQI value approach. SQI is calculated based on the criteria proposed by Mausbach & Seybold (1998), which is suitable for field conditions using analysis of Minimum Data Set (MDS). The parameters analyzed include rooting depth, soil texture, bulk density, total porosity, pH of the soil, C-organic, N-total, P-available, K-exchangeable and soil respiration. The result showed that the quality criteria of the soil in the study area consists of three classes, namely: low, medium and high, which have soil quality index values of 0.27, 0.52, and 0.64 respectively. Based on the study\u27s soil quality criteria, the area of research was mapped accordingly by class: (1) high, covering an area of 14016.98 ha (60.38%); (2) medium, covering an area of 8542,90 ha (36.79%); and low, covering an area of 658,18 ha (2.83%). Types of land use categorized as having high quality, were primary forest, secondary forest and residential area with respective values of 0.66; 0.64, and 0.63. Open land, grassland, moor, rice field and shrubs were of medium quality, with respective values of 0.47; 0.48; 0.52; 0.51 and 0.55. The main and additional components affecting the hydrological disaster vulnerability on soil quality parameters are land use change, and soil properties. The findings of this research have implications structural efforts to mitigate hydrological disasters (dams, catchment wells, biopori, tillage conservation, terracing), and non-structural efforts (maps of soil quality, agroforestry, cover crops, materials of soil conditioner, organic matter). These efforts are necessary to improve and to maintain soil quality longitudinall