No abstract

Lake Limboto is one of the major lakes in Sulawesi, Indonesia. It is currently undergoing serious degradation due to population pressure. As more residential areas have been established around the lake, the sedimentation rate has increased because of the contribution of anthropogenic particles. In this study, the lithogenic and anthropogenic components in surface sediments from 17 points in the lake were studied and identified using a combination of magnetic and geochemical analyses. The results showed that although the magnetic susceptibility values in R (residential) and NR (non-residential) areas were relatively similar, the values of saturation isothermal remanent magnetization (SIRM) as well as those of SIRM/χ LF differed significantly, implying that the magnetic characteristics of the lithogenic component (in the NR area) differ from those of the anthropogenic component (in the R area). The discrepancy between the anthropogenic and lithogenic contributions was further supported by trace metals and rare earth element (REE) contents. Sediment samples in the R area contained higher levels of Mn, La, Pr, and Gd, while in the NR area they contained higher levels of Fe, Sc, Nd, and Ce. The magnetic susceptibility also correlated strongly with Fe, Cu, Zn, and Mn contents in the NR area. A similar correlation was not observed in the R area. The results above imply that a combination of magnetic and geochemical analyses can successfully differentiate lithogenic and anthropogenic components or contributions in lake sediments.

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. In the laboratory, a series of magnetic measurements was conducted on sediment samples i.e. magnetic susceptibility, ARM (Anhysteretic Remanent Magnetization) and IRM (Isothermal Remanent Magnetization). These environmental magnetism data were used to characterize bulk surface sediments in the study area.

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. Extracted magnetic grains were also subjected to magnetic hysteresis analyses as well as XRD and SEM analyses. These data are invaluable in identifying the contribution of each river (and its catchment area) to the surface sediments of Lake Limboto.

Kondisi geografis Desa Hutadaa yang masih relatif dekat dengan pusat Kabupaten Gorontalo seharusnya mendapat perhatian penting untuk menjadi salah satu desa yang dapat mendukung perekonomian yang berbasis lingkungan. Bahkan menariknya, desa ini berbatasan langsung dengan perairan Danau Limboto sebagai asset sumber daya alam sekaligus sebagai icon Provinsi Gorontalo. Kehadiran Danau Limboto ini sangat potensial untuk menumbuhkan ekonomi masyarakat yang dapat digerakkan pada pada sektor perikanan, pariwisata, dan juga sektor perekonomian. Namun ternyata banyak masalah yang ditemukan di desa ini terutama rendahnya pertumbuhan ekonomi, tingginya angka stunting, DBD, kerusakan lingkungan yang tandai dengan kejadian banjir maupun kekeringan serta tumpukan sampah.  Berdasarkan permasalahan yang ditemukan di Desa Hutadaa, maka solusi yang telah dilaksanakan adalah strategi ProKlim berbasis partisipasi masyarakat yang sinergi dengan pencapaian SDGs terutama goals 3 (kesehatan yang baik dan kesejahteraa), 6 (air bersih dan sanitasi), dan 13 (penanganan perubahan iklim). Strategi ProKlim di Desa Hutadaa ini telah dirintis melalui program Kuliah Kerja Nyata (KKN) oleh mahasiswa Universitas Negeri Gorontalo selama 45 hari dengan harapan dapat dilakukan secara berkelanjutan. Adapun luaran yang telah dicapai dalam program pengabdian ini adalah inovasi pembuatan biopori, penghijauan dan pemanfaatan pekarangan, pembentukan kelompok usaha Bank Sampah, pembuatan Pupuk Kompos dan pupuk organik cair, program posyandu remaja, pembuatan spot foto untuk desa wisata, pembuatan peta perencanaan aliran drainase, peta adminsitrasi Desa Hutadaa, dan juga peta tanggap bencana alam. Namun hasil program pengabdian ini masih membutuhkan program KKN lagi untuk melanjutkan dan mengembangkan luaran yang telah dihasilkan