Karbon Biomassa Mikroba Sebagai Indikator Kualitas Tanah Di Lahan Penambangan Pasir

Fauziana, Herni Maulidya (2019) Karbon Biomassa Mikroba Sebagai Indikator Kualitas Tanah Di Lahan Penambangan Pasir. Sarjana thesis, Universitas Brawijaya.

Abstract

Penambangan batu dan pasir di lahan-lahan pertanian dan tebing-tebing sungai dapat memberikan tambahan pendapatan bagi masyarakat di Kecamatan Wajak, karena material letusan gunung berapi umumnya berkualitas bagus dan banyak dibutuhkan untuk pembangunan berbagai macam bangunan. Namun demikian, kegiatan penambangan pasir tersebut mengakibatkan degradasi keanekaragaman hayati dan kesuburan tanah sehingga terjadi penurunan biomassa tanaman dan cadangan karbon. Reklamasi lahan sisa penambangan pasir umumnya menggunakan jenis pohon dengan pertumbuhan cepat seperti sengon (Paraserianthes falcataria) yang kadang-kadang dikombinasikan dengan tanaman kopi ataupun dengan tanaman semusim. Masukan seresah yang beragam (jumlah dan kualitasnya) melalui penanaman pohon ini bermanfaat untuk mempertahankan kelembaban tanah dan meningkatkan aktivitas organisma tanah. Salah satu indikator perbaikan kualitas tanah dapat diukur dari tingkat karbon biomassa mikroba (MBC), dimana semakin besar MBC berarti kesuburan tanah semakin membaik. Tujuan penelitian: (1) Untuk mengevaluasi dampak penambangan pasir terhadap MBC, (2) Untuk mengevaluasi pengaruh penggunaan lahan agroforestri pada lahan bekas penambangan pasir terhadap MBC. Penelitian ini dilakukan di Kecamatan Wajak, Kabupaten Malang, pada bulan Mei hingga Oktober 2018. Contoh tanah diambil dari sub-plot berukuran 400 m2 dengan kedalaman tanah 30 cm, dari 3 macam lahan: (1) Agroforestri multistrata (AFM), (2) Agroforestri sederhana (AFS) dan (3) lahan tanaman semusim monokultur (TS). Ketiga jenis lahan tersebut dipilih dari 3 lokasi penambangan pasir yang berbeda: (1) lahan sudah pernah ditambang (ST), (2) lahan yang belum pernah ditambang (BT), dan (3) lahan yang masih “sedang” ditambang (MT), dengan jumlah ulangan 3 kali. Pengukuran yang dilakukan: total MBC (metode fumigasiekstraksi), Berat Isi tanah, pH, dan total C-organik. Kegiatan penambangan pasir di lokasi penelitian menurunkan hampir 50% MBC dari 0,58 μg C g-1 menjadi 0,32 μg C g-1. Adanya penambahan bahan organik ke dalam tanah (berupa pupuk kandang dan pupuk kimia) setelah penambangan, meningkatkan MBC (sekitar 50%) dari 0,32 μg C g-1 menjadi 0,69 μg C g-1, dan total C-organik juga meningkat dari 0,8 % menjadi 1,4 %, namun hasil yang diperoleh semuanya masih tergolong rendah. MBC di sistem agroforestri multistrata lebih besar (rata-rata 0,79 μg C g-1) dibandingkan di tanah agroforestri sederhana (rata-rata 0,56 μg C g-1), maupun pada lahan kosong yang tidak ditanami (rata-rata hanya 0,32 μg C g-1). Hasil pengukuran MBC dan kadar C-organik tanah merupakan indikator kualitas tanah yang cukup kuat untuk mengevaluasi usaha reklamasi lahan bekas tambang

English Abstract

Mining of stone and sand on agricultural lands and river banks can provide additional income for farmers in Wajak District, because volcanic eruption materials are generally good quality and are needed for the construction of various kinds of buildings. However, these sand mining activities result in biodiversity degradation, decline soil fertility and a decrease in plant biomass and carbon stocks. Reclamation of sand mining land is generally planted with fast-growing tree species such as sengon (Paraserianthes falcataria) which are sometimes combined with coffee tree or annual crops. Diverse litter input (quantity and quality) is useful for maintaining soil moisture and soil microbial activity. Indicators of soil quality improvement can be measured from the level of microbial biomass carbon (MBC), the higher MBC the better soil quality would be. The objectives of this study are (1) To evaluate the impact of sand mining on MBC, (2) To evaluate the improvement of soil quality (level of MBC) on agroforestry systems in the sand mining area. This research was conducted in Wajak District, Malang Regency, from May till October 2018 Soil samples taken from sampling plot sized of 400 m2 of soil depth 30 cm, from 3 types of land uses: (1) Multistrata agroforestry (AFM), (2) simple Agroforestry (AFS) and (3) monoculture annual crop land (TS). Those three land uses were located in 3 different sand mining locations: (1) land that had been mined (ST), (2) land that had never been mined before (BT), and (3) land where mining is still on going (MT), with the number of replications 3 times. Measurements made are MBC (fumigation-extraction method), soil bulk density, soil pH and total C-organic. Sand mining activities at the study site reduced the value of MBC from 0.58 μg C g-1 to 0.32 μg C g-1. The addition of organic matter (manure) into the soil after mining and combined with chemical fertilizer application, resulted 50% increase of MBC from 0.32 μg C g-1 to 0.69 μg C g-1, and C-organic concentration increased from 0.79% to 1.39% but the obtained results are still relatively low. MBC in the multistrata agroforestry system is greater (an average of 0.79 μg C g-1) compared to simple agroforestry (an average of 0.56 μg C g-1), and on bare land (an average of 0.32 μg C g-1). Measurements of MBC and soil C-organic content are good indicators of soil quality to evaluate the success of land reclamation efforts on sand mining area.

Other obstract

-

Item Type: Thesis (Sarjana)
Identification Number: SKR/FP/2019/876/052000928
Subjects: 600 Technology (Applied sciences) > 631 Specific techniques; apparatus, equipment materials > 631.4 Soil science > 631.47 Soil and land-use surveys
Divisions: Fakultas Pertanian > Ilmu Tanah
Depositing User: Nur Cholis
Date Deposited: 21 Jul 2020 12:43
Last Modified: 25 Oct 2021 07:04
URI: http://repository.ub.ac.id/id/eprint/179505
[thumbnail of HERNI MAULIDYA FAUZIANA (2).pdf]
Preview
Text
HERNI MAULIDYA FAUZIANA (2).pdf

Download (6MB) | Preview

Actions (login required)

View Item View Item