BIODIVERSITAS ISSN: 1412-033X Volume 23, Number 2, February 2022 E-ISSN: 2085-4722 Pages: 1181-1187 DOI: 10.13057/biodiv/d230264 Arbuscular mycorrhizal fungi inoculum and soil ameliorants enhance the growth of Falcataria moluccana in revegetation of post-silica sand mining land in Sukabumi, Indonesia HABIB SATRIO BEKTI, SRI WILARSO BUDI  , CAHYO WIBOWO Department of Silviculture, Faculty of Forestry and Environment, Institut Pertanian Bogor. Jl. Ulin, Lingkar Akademik Kampus IPB, Dramaga, Bogor 16680, West Java, Indonesia. Tel.: +62-251-86268806, Fax.: +62-251-8626886,  email: wilarso62@yahoo.com; budisw62@gmail.com Manuscript received: 6 January 2022. Revision accepted: 30 January 2022 Abstract. Bekti HS, Budi SW, Wibowo C. 2022. Arbuscular mycorrhizal fungi inoculum and soil ameliorants enhance the growth of Falcataria moluccana in revegetation of post-silica sand mining land in Sukabumi, Indonesia. Biodiversitas 23: 1181-1187. Open-pit mining of silica sand caused several negative impacts on the environment, especially inhibited plant growth. MycoSilvi is Arbuscular Mycorrhizal Fungi (AMF) inoculum enriched with Mycorrhizal Helper Bacteria (MHBs) which could increase plant growth and nutrient uptake in degraded soils. A field experiment was conducted to study the growth response of F. moluccana (Miq.) Barneby & JW Grimes seedlings treated with MycoSilvi inoculation and soil ameliorants (lime and compost) in post-silica sand mining land. The experimental design used in this study was a completely randomized block design with a factorial scheme. The results showed that MycoSilvi inoculation combined with soil ameliorant significantly improved plant growth of F. moluccana and assisted plant survival within nine months after transplantation in the field. MycoSilvi inoculation and soil ameliorants also increased the number of bacteria in the soil rhizosphere compared with control treatment. This study indicated that revegetation with MycoSilvi inoculation and soil ameliorants could influence plant establishment and development of microbial soil communities in infertile soils, suggesting that it could be an effective method for further ecological rehabilitation in degraded land areas. Keywords: Falcataria moluccana, MycoSilvi, post-silica sand mining, revegetation, soil ameliorant INTRODUCTION Mining activities in Indonesia always increase every year. Based on data from the Indonesian Ministry of Environment and Forestry (2020), Indonesia has a total mining concession area of 810,400 ha in 2019, 346,000 ha of which are forest areas. Open-pit mining of silica sand caused several negative impacts on the environment, i.e., vegetation cover loss, fauna and soil microbes decline, nutrient deficiency, soil acidification, and soil contamination with heavy metals, which are toxic for plant growth (Cristescu 2012; Huot 2015; Gastauer 2018; Diatin 2018; Syauqie 2019). Revegetation is one of the main ways to improve and restore post-mining land. The vegetation can stabilize the soil by developing extensive root systems (Sheoran et al. 2010) and prevent the spread of heavy metal particles carried by erosion (Arienzo et al. 2004). Therefore, revegetation is an important indicator in determining the success of post-mining land rehabilitation. However, post- mining land is a very unfavorable environment for plants due to many inhibiting factors for plant growth (Sudrajat et al. 2019; Tordoff et al. 2000). The symbiosis of Arbuscular Mycorrhizal Fungi (AMF) with plants could support plant growth by increasing nutrient uptake, especially P (phosphorus). MycoSilvi is an AMF inoculum enriched with Mycorrhizal Helper Bacteria (MHBs), which we developed, to significantly increase phosphorus uptake, plant height, and stem diameter in post- silica sand mining in greenhouse experiments (Budi et al. 2020; Munawaroh et al. 2020). Therefore, it is necessary to test their effectiveness in the field. In acidic post-mining soils, the addition of soil ameliorants such as lime and compost also play a role in increasing soil pH, soil organic carbon, and soil macro-nutrients (Córdova et al. 2011; Wasis and Andika 2017). Apart from soil improvement, the selection of plant species is another important part of the revegetation stage in post-mining land. Falcataria moluccana (Miq.) Barneby & JW Grimes is generally recognized as an adaptive fast- growing tree species that can be planted intensively for post-mining land rehabilitation (Prematuri et al. 2020; Suita et al. 2018). This plant can fix nitrogen into the soil and has a mutualistic symbiosis with AMF, making it better to be used for revegetation (Ramos et al. 2019). The objectives of this study were to analyze the growth response of F. moluccana seedlings inoculated with various variants of MycoSilvi in post-silica sand mining land amended with soil ameliorants and to analyze the soil bacteria communities in post-silica sand mining land after being treated with soil ameliorants and MycoSilvi inoculation. MATERIALS AND METHODS Preparation of planting area This experiment was carried out in silica sand post- mining land of PT Solusi Bangun Indonesia, which was located in Cibadak, Sukabumi District, West Java,