A soil amendment is any material added to a soil to improve soil physical properties, support plant growth, improve soil fertility, organic matter, and water holding capacity, improve soil chemical and biological properties. Biochar is an organic amendment that improve soil fertility, mitigates climate change, and effectively keeps nutrients and available to plants. The chemical and physical properties of the biochar are important to know the suitable applications of biochar. The chemical and physical properties of the biochar are depending on the process and biomass feedstock. The research aimed to find out the kind of biomass feedstock for biochar as a soil amendment. The biochar feedstock was evaluated using scanning electron microscopy (SEM) and electron dispersive X-ray (EDX) analysis and can predicting possible uses for the biochars. The result showed that the biochar surface morphology properties were influenced by the feedstock types and pyrolysis temperature. The pores development and mineral contents in coconut shell biochar are the most suitable for soil amendment.

Agricultural improvement (AI) in dryland became a priority for agricultural development in Aceh Province, Indonesia. AI is in line with government programs to increase the productivity of several types of second food crops such as peanuts. Up to now, the productivity of food crops, especially peanut on dryland in Aceh Province, based on farmers’ practice, was still very low, i.e 0.95 tons ha-1. Biochar is one of the options for soil management and has the potential to improve soil fertility. The objectives of this research were to study the effect of rice husk biochar residue, cocopeat biochar residue, and cow manure residue on Entisol chemical properties, peanut growth, and production. Rice husk biochar, cocopeat biochar, and cow manure were applied on the first season of peanut growth. The research was conducted using factorial 6 × 3 with three replications, and the treatment units were allocated based on Randomized Block Design. The first factor was rice husk biochar residue and cocopeat biochar residue with 3 doses (0; 2.5; 5 t ha-1) and cow manure residue with 3 doses (0; 2.5; 5 t ha-1) as the second factor. The soil chemical properties and root samples were analyzed on 45 days after planting and peanut production after harvest. The observed variables of crops were (1) plant height, (2) branches number (3) plant dry weight; (4) root dry weight; (5) root nodules number, (6) pods weight, (7) pods total, (8) filled pods, (9) seed weight, and (10) weight of 100 seeds. The observed variables of soil chemical properties were (1) pH, (2) C-organic; (3) Total N; (4) P available; and (5) K exchangeable. The results showed that rice husk biochar residue and cocopeat biochar residue does not affect soil chemical properties significantly, such as plant height 15 and 30 DAP, peanut pods, and seed weight per plant. Nevertheless, both had a positive effect on plant height 45 DAP, branches number 15, 30, 40 DAP, root dry weight, plant dry weight, root nodules number, and 100 seeds weight. The best residual dosage of rice husk biochar and cocopeat biochar was 2.5 t ha-1. Cow manure residue did not give a significant effect on soil chemical properties, plant height 15, 30 and 45 DAP, branches number 30, 45 DAP, root dry weight, plant dry weight, root nodules number, peanut pods, seed weight per plant, and 100 seeds weight, but had a positive effect on the number of branches 15 DAP. The best dosage of cow manure residue was 2.5 t ha-1

This study aims to determine the effect of young coconut waste biochar and goat manure application on the chemical properties of the entisol. The Biochar Research Station, Universitas Syiah Kuala, conducted the research. This study used a factorial randomized block design consisting of two factors. The first factor was the dose of young coconut waste biochar (0, 5, and 10 t ha-1), and the second was the dose of goat manure (0, 5, 10, and 15 t ha-1). Parameters observed in this study were soil chemical properties analysis of entisol (pH, organic C, total N, available P, and exchangeable K). The results showed that the young coconut waste biochar application could affect the soil’s chemical properties, especially the soil exchangeable K. Young coconut waste biochar application can increase the exchangeable soil K in tomato cultivation land. The application of goat manure did not affect the soil’s chemical properties in tomato cultivation land.

Climate change that occurs globally in agriculture causes fail crops production, causing losses for farmers. This loss can be minimized by using rice straw mulch to reduce soil temperature and protect the soil from direct solar radiation on lettuce land. This study will examine whether treatment with rice straw mulch can affect soil temperature in lettuce land. The research was conducted at Nudira Fresh Green House PT. Nudira Sumber Daya Indonesia, Warnasari Village, Pangalengan Subdistrict, Bandung District, West Java. This research was conducted from March 1, 2022 to August 31, 2022. The data of this study used a factorial 4 x 2 Randomized Block Design with 3 replications. Factor I was the thickness of rice straw mulch 0 t ha− 1 (R0), 4 t ha−1 or 0.48 kg plot−1 (R1), 6 t ha−1 or 0.72 kg plot−1 (R2), and 8 t ha−1 or 0.96 kg plot−1 (R3) and factor II was the dose of cow manure (F1) and compost (F2) each 20 t ha−1 or 2.4 kg plot−1. The results showed that the application of rice straw mulch with the organic fertilizer has not significant effect on soil temperature in lettuce land. However, the application of rice straw mulch at a dose of 8 t ha−1 slightly better results in decreasing soil surface temperature at a depth of 0 cm, although not significantly different.

Lettuce is one of the most popular horticultural crops. It is necessary to make an effort to increase lettuce production to meet market demand. One of the efforts is engineering cultivation systems through rice straw mulch and organic fertilizers application. The aims of studied to determine the effect of rice straw mulch and organic fertilizer on growth and production of lettuce. The research was conducted at Nudira Fresh Green House, PT. Nudira Sumber Daya Indonesia, Warnasari Village, Pangalengan Subdistrict, Bandung District, West Java. This study used factorial randomized block design with 3 replications. There were 2 factors with 8 treatment combinations. Factor I was mulch dose: control, 4 t ha−1 rice straw mulch, 6 t ha−1 rice straw mulch, 8 t ha−1 rice straw mulch. Factor II was organic fertilizer types: 20 t ha−1 cow manure, and 20 t ha−1 compost. The results showed that the rice straw mulch dose and organic fertilizer type did not significantly effect on plant height, leaves number, production per plant sample, and production per plant plot. Application of 8 t ha−1 rice straw mulch was able to increase plant height, production per plant sample, and production per plant plot. The cow manure application was able to increase plant height, leaves number, production per plant plot, and production per plant sample compared to using compost.