A 1 Ma sedimentary ancient DNA (sedaDNA) record of catchment vegetation changes and the developmental history of tropical Lake Towuti (Sulawesi, Indonesia).

Studying past ecosystems from ancient environmental DNA preserved in lake sediments (sedaDNA) is a rapidly expanding field. This research has mainly involved Holocene sediments from lakes in cool climates, with little known about the suitability of sedaDNA to reconstruct substantially older ecosystems in the warm tropics. Here, we report the successful recovery of chloroplast trnL (UAA) sequences (trnL-P6 loop) from the sedimentary record of Lake Towuti (Sulawesi, Indonesia) to elucidate changes in regional tropical vegetation assemblages during the lake's Late Quaternary paleodepositional history.

Magnetic susceptibility in the assessment of toxic heavy metal elements in the surface sediments of Inner Ambon Bay, Maluku province, Indonesia.

The Inner Ambon Bay (IAB) is an important area for the economic development of the city of Ambon, one of only a few urban areas in eastern Indonesia. This study is intended to monitor the anthropogenic impact on IAB by employing combined rock magnetic and geochemical analyses on 20 samples collected from IAB and the surrounding rivers. Magnetic susceptibility values of samples in the IAB averaged 26.

The strength, position, and width changes of the intertropical convergence zone since the Last Glacial Maximum.

The intertropical convergence zone (ITCZ) plays a key role in regulating tropical hydroclimate and global water cycle through changes in its convection strength, latitudinal position, and width. The long-term variability of the ITCZ, along with the corresponding driving mechanisms, however, remains obscure, mainly because it is difficult to separate different ITCZ variables in paleoclimate proxy records. Here, we report a speleothem oxygen isotope (δO) record from southwestern Sulawesi, Indonesia, and compile it with other speleothem records from the Maritime Continent.

Magnetic susceptibility and heavy metal contents in sediments of Riam Kiwa, Riam Kanan and Martapura rivers, Kalimantan Selatan province, Indonesia.

Kalimantan Selatan is proud of the Martapura River's natural and cultural history. Martapura tributaries include Riam Kanan and Kiwa. The Martapura River is essential because it provides clean water and a livelihood for riverside residents.

Magnetic susceptibilities of surface sediments from estuary rivers in volcanic regions.

Estuaries have very complex mechanisms because they are influenced by seawater intrusion, which causes enrichment of contaminants in the maximum turbidity area. Magnetic susceptibility measurements have been used for monitoring a wide variety of environments. However, there have been few studies of the magnetic properties of surface sediments from estuaries in volcanic environments in the tropics.

Magnetic susceptibility and grain size distribution as prospective tools for selective exploration and provenance study of iron sand deposits: A case study from Aceh, Indonesia.

Almost all of the iron sand found in Indonesia, from Sumatra to Papua, is sandy deposit. Despite its variety of minerals, iron sand is commonly mined for low economic uses such as building material. As iron sands from different localities might have different characteristics (grain-size distribution, mineralogy, magnetic properties), such characteristics might in turn be used for provenance study or for selective mining.

Organic matter mineralization in modern and ancient ferruginous sediments.

Deposition of ferruginous sediment was widespread during the Archaean and Proterozoic Eons, playing an important role in global biogeochemical cycling. Knowledge of organic matter mineralization in such sediment, however, remains mostly conceptual, as modern ferruginous analogs are largely unstudied. Here we show that in sediment of ferruginous Lake Towuti, Indonesia, methanogenesis dominates organic matter mineralization despite highly abundant reactive ferric iron phases like goethite that persist throughout the sediment.

Petrology and geochemistry dataset of lava from the Ijen Crater and Mount Blau, Banyuwangi, East Java, Indonesia.

This article presents rock texture and mineralogy, as well as major and trace elements of lava from Ijen Crater and Mount Blau, Ijen Volcanic Complex (IVC), East Java, Indonesia related to article entitled "Rock Magnetic, Petrography, and Geochemistry Studies of Lava at the Ijen Volcanic Complex (IVC), Banyuwangi, East Java, Indonesia" [1]. Six lava samples were taken from three lava flows that are the product of the eruption of the Ijen Crater and three lava samples from a lava flow that is the product of the eruption of Mount Blau. The samples were crushed and used for measuring major and trace elements using XRF method.

Magnetic mineral characteristics, trace metals, and REE geochemistry of river sediments that serve as inlets to Lake Limboto, Sulawesi, Indonesia.

This article presents magnetic mineral characteristics, trace metals, and REE geochemistry of river sediments that serve as inlets to Lake Limboto, Sulawesi, Indonesia related to article entitled "Lithogenic and anthropogenic components in surface sediments from Lake Limboto as shown by magnetic mineral characteristics, trace metals, and REE geochemistry" [1]. River sediments were obtained from three rivers, namely Alopohu, Bionga, and Talumelito. Sieved sediments were subjected to magnetic susceptibility measurements as well as geochemical analyses that include AAS analyses for trace metals and ICP-OES for REE.

Environmental magnetism data of Brantas River bulk surface sediments, Jawa Timur, Indonesia.

This article presents measurement data using environmental magnetism method on the bulk surface sediments related to the research article entitled "Heavy metal contents and magnetic properties of surface sediments in volcanic and tropical environment from Brantas River, Jawa Timur Province, Indonesia" Mariyanto et al., 2019. Surface sediments were taken from 20 different locations along Brantas River.

Heavy metal contents and magnetic properties of surface sediments in volcanic and tropical environment from Brantas River, Jawa Timur Province, Indonesia.

Brantas River is a largest urban river supplying raw water and drainage in Jawa Timur Province, Indonesia. Dense population along the river is a threat of pollution due to anthropogenic pollutants. In this study, we characterize the magnetic properties and heavy metal contents of surface sediments in various locations along the Brantas River.

Magnetic characterizations of nickel hyperaccumulating plants (Planchonella oxyhedra and Rinorea bengalensis) from Halmahera, Indonesia.

Magnetic minerals, such as magnetite and hematite, have been reported to be present, in particular, leaves as biogenic particles. The magnetic minerals and properties of Ni hyperaccumulators have not previously been reported in the literature. This study aimed to characterize the magnetic properties of two Ni hyperaccumulating plant species, R.

Glacial forcing of central Indonesian hydroclimate since 60,000 y B.P.

The Indo-Pacific warm pool houses the largest zone of deep atmospheric convection on Earth and plays a critical role in global climate variations. Despite the region's importance, changes in Indo-Pacific hydroclimate on orbital timescales remain poorly constrained. Here we present high-resolution geochemical records of surface runoff and vegetation from sediment cores from Lake Towuti, on the island of Sulawesi in central Indonesia, that continuously span the past 60,000 y.

Scanning electron microscopy and magnetic characterization of iron oxides in solid waste landfill leachate.

Leachate sludge samples were taken from two municipal solid waste sites of Jelekong and Sarimukti in Bandung, Indonesia. Their magnetic mineralogy and granulometry were analyzed to discriminate the sources of magnetic minerals using X-ray diffraction (XRD), scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy (SEM-EDX) and rock magnetism. SEM-EDX analyses infer that the main magnetic minerals in the leachate sludge are iron oxides.