In Aceh, Indonesia, low dryland crop yields entrench rural poverty. The lack of soil fertility information hinders the development of soil management programs to assist farmers to increase crop yield. This study identified soil-based constraints to production and management options to increase crop yield. We analysed 254 soil samples from 127 dryland cropping sites across Pidie, Bireuen, Aceh Besar and Aceh Barat districts for pH, soil organic carbon (SOC), total nitrogen (N), phosphorus (P), base saturation (BS) and cation exchange capacity (CEC). The dominant soils were Entisols, Inceptisols and Ultisols, with some Andisols and Mollisols. Overall, the CEC range was 10–60 cmol(+) kg–1 and available P was 0.5–702 mg kg–1 but most had poor fertility: SOC < 20.0 g kg–1, total N < 2.0 g kg–1, low basic cations and BS < 40%. The Ultisols and some Entisols and Inceptisols were acidic, with aluminium saturation >20% and available P < 6.5 mg kg–1. To sustainably increase crop yield, we concluded that these soils need lime where acidic, fertilisers for nutrients and stable carbon-rich amendments for system stability. This dataset will guide future agricultural research and development programs in Aceh to improve farmer practices and food security.

The flood phenomenon in the Krueng Jreue Sub-Watershed, Aceh Besar, Indonesia, in recent years indicates biophysical damage to the land. Floods are influenced by factors from biophysical conditions of the land and high rainfall with small river cross-sectional capacity causing water to overflow the embankment and flood low areas. This research aims to analyse the flood vulnerability level in the Krueng Jreue Sub-Watershed, Aceh Besar, Indonesia. The results showed that flood vulnerability in the research area consisted of four classes: very vulnerable, vulnerable, moderately vulnerable and somewhat vulnerable, with each area averaging a score of 43.0, 38.8, 30.0 and 21.7. Types of land use that are particularly vulnerable to flooding are rice fields with a mean total score of 43.0. The vulnerable classes are found in settlements and moorings, with a total score of 42.0 and 36.5, respectively. While open land, shrubs, grasslands, primary forests and secondary forests are quite vulnerable to flooding, with a mean total score of 32.5 each: 30.0, 30.0, 28.0 and 27.0. The main components affecting flood vulnerability are rainfall, temperature and land use, while additional components are soil infiltration and slope. Mechanised hydrological disaster mitigation can be performed through optimisation of weir, embung, rorak and check-dam. Vegetative hydrological mitigation efforts can be performed by reforestation and agroforestry systems, maps and flood prediction. Non-technically, hydrological disaster mitigation efforts can be undertaken with legal policies, law enforcement, map creation and prediction of droughts and socialisation of legislation.

Soil surface charge and cation exchange are important parameters of soil fertility in tropical soils. This study was conducted to investigate characteristics of surface charges and cation exchanges on four soil orders of the dryland in Aceh Besar district. The soil order includes Entisols Jantho (05o16’58.41” N; 95o37’51.82” E), Andisols Saree (05o27'15.6" N; 95o44'09,1" E), Inceptisols Cucum (05º18’18,37” N; 95º32’48,04” E), dan Oxisols Lembah Seulawah (05o27’19,4” N; 95o46’19,2” E). The charge characteristics of surface charge are evaluated from the parameter of DpH (pHH2O-pHKCl), variable charge (Vc), permanent charge (Pc), and point of zero charges (PZC). In contrast, cation exchange properties are evaluated from several soil chemical properties, such as soil organic matter (SOM), base saturation (BS), cation exchange capacity (CEC), and effective CEC (ECEC). The results show that the four pedons of soil in the hilly dryland of Aceh Besar include a variable charge because it has a PZC, which is characterized by a negative surface charge with a PZC of pHH2O and has CEC dependent soil pH. PZC value varies from 3.21 – 5.26 and sequentially PZC Andisols Oxisols Entisols Inceptisols. The total CEC value differs considerably from ECEC and the sum of cations. CEC total of the soils varies from 12.8 – 34.4 cmol kg-1, whereas the ECEC values vary from 2.72 – 8.66 cmol kg-1. The highest variable charge percentage is found in Andisols Saree. In contrast, the highest permanent charge is found in Inceptisols Cucum and is positively correlated with pHH20, PZC, CEC, and sums of cations or ECEC. Improving soil quality in hilly dryland soils in Aceh Besar District can be done by decreasing the PZC status of soils with organic amendments and fertilizers or increasing the pH by using liming.

A process called bioremediation can be used to turn abandoned mining sites into useful agricultural land. An alternative to enhancing the quality of the ex-siltstone mining soil so that it can be used again as agricultural land is the application of biocompost fertilizer. This study intends to investigate how biocompost might enhance the ex-siltstone mining soil’s quality in incubation treatments. The composition of biocompost used in this study is ingredient I: (a) cow manure = 50%; (b) chicken manure = 30%; (c) sand = 10%; (d) bacteria (bioactivator) = 10%; ingredient II: ingredient I is mixed with cow manure in a composition ratio of 1 : 2. The ex-mining soils were gathered in the ex-cement mining region of Lhoknga Subdistrict, Aceh Besar District (5.45°N, 95.2°E). Incubation experiments were conducted in incubation pots (approximately 5 kg per pot) that were randomly placed in a greenhouse using a 4 × 4 factorial completely randomized design (CRD) with three replications. The first factor is the ratio of ex-siltstone mining soil : biocompost, which consists of four levels of comparison: control (ex-mining soil not incubated), 1 : 1 (50 : 50), 1 : 2 (33 : 67), and 1 : 3 (25 : 75). The second factor is the incubation period, which has four levels: 0, 2, 4, and 6 weeks with 48 experimental units. Indicators of the impact of biocompost on the physical and chemical quality of ex-siltstone mining soil were examined. The result shows that bioremediation of ex-siltstone mining soil with biocompost application improves the quality of ex-siltstone mining soil by decreasing bulk density and permeability and also increasing porosity, decreasing soil pH from alkaline to neutral, and increasing soil organic C, total N, available P, and total K. The incubation period of ex-siltstone mining soil influences the changes and dynamics of the soil’s chemical properties.

Background: Water stress is one of the most crucial limiting factors in maize production on Ultisols. One solution that could be adopted to solve this problem is applying organic soil amendment. Methods: This study evaluated three varieties of corn: NK-Jumbo, Srikandi Kuning and Lamuru. The water stress treatment consists of 75% field capacity (without water stress) and 37.5% field capacity (water stress treatment). The organic amendment consists of without soil amendment, rice-straw 10 tons ha-1, biochar 10 tons ha-1 and rice straw 5 tons ha-1 + biochar 5 tons ha-1. A factorial, completely randomized design was used in this research. Result: Water stress and organic amendments affect total stomata, leaf curl, leaf area, proline content, shoot and root dry weight, shoot-root ratio and biomass production of corn. Applying organic amendments increases corn’s resistance to water stress, indicated by decreased plant proline content and increased biomass. The proline content of corn by application of organic amendment with rice straw 5 tons ha-1 + biochar 5 tons ha-1 (70.41 µ mol/g) was lower than the proline content of treatment without amendments (93.69 µ mol/g). NK-Jumbo was the most resistant variety to water stress conditions.