Struktur Komunitas Mikoriza Arbuskular Pada Tipe Penggunaan Lahan dan Karakteristik Tanah di Taman Hutan Raya Wan Abdul Rachman Lampung

Abstract

Land-use change is one of the major forms of anthropogenic disturbance that can alter soil characteristics, vegetation composition, and the habitat conditions of soil organisms. Such changes also affect the structure of soil microbial communities, including arbuscular mycorrhizal fungi (AMF), which play important roles in nutrient uptake, soil aggregate formation, and enhancing plant tolerance to environmental stress. AMF community structure is influenced by the interaction of several factors, particularly soil characteristics, vegetation, and land use. However, information on the relationships among these factors in Wan Abdul Rachman Forest Park (Tahura WAR), Lampung, remains limited. Therefore, this study was conducted to describe the AMF community structure across three land-use types and its relationship with soil characteristics. This study aimed to characterize soil properties, compare AMF community structure, and explain the relationships between soil characteristics and the genus composition and community structure parameters of AMF across three land-use types, namely multistrata agroforestry, simple agroforestry, and shrubland in Tahura WAR. The study was conducted from August to December 2025 in the utilization block of Tahura WAR, Lampung. Analyses of soil characteristics, AMF isolation and identification, and root colonization were carried out at the Soil Biotechnology Laboratory, Department of Soil Science and Land Resources, Faculty of Agriculture, IPB University, and the Soil Science Laboratory, Faculty of Agriculture, University of Lampung. Each land-use type was represented by a single 50 × 50 m plot consisting of three 5 × 5 m subplots. Composite soil and root samples were collected from the 0-20 cm soil layer within the rhizosphere. The observed variables included soil physical and chemical characteristics, spore population, genus composition, the Shannon-Wiener diversity index, and AMF root colonization. Data were analyzed using Principal Component Analysis (PCA), Linear Mixed Models (LMM) followed by Estimated Marginal Means (EMMs), Redundancy Analysis (RDA), and Spearman’s correlation analysis. The results showed that soil characteristics differed among the land-use types. Multistrata agroforestry was characterized by higher soil organic carbon, available phosphorus, and aggregate stability than simple agroforestry and shrubland, whereas shrubland was characterized by higher bulk density. PCA indicated that soil characteristics were able to distinguish the three land-use types. Multistrata agroforestry was associated with higher soil organic carbon, pH, available phosphorus, porosity, and aggregate stability, whereas shrubland was associated with higher bulk density. Simple agroforestry occupied an intermediate position between the other two land-use types. Eight AMF genera were identified, namely Glomus, Acaulospora, Diversispora, Gigaspora, Septoglomus, Sclerocystis, Paraglomus, and Funneliformis. LMM analysis showed that land-use type significantly affected AMF genus diversity and root colonization but had no significant effect on spore population. The AMF community was dominated by Glomus and Acaulospora based on relative abundance and relative frequency. RDA showed that variation in AMF genus composition was associated with bulk density, pH, soil organic carbon, available phosphorus, total phosphorus, and soil aggregate stability. Glomus and Acaulospora were associated with bulk density, whereas Diversispora and Paraglomus were associated with pH, available phosphorus, and aggregate stability. Funneliformis was associated with soil organic carbon, total phosphorus, and available phosphorus, whereas Gigaspora, Septoglomus, and Sclerocystis showed relatively weak relationships with the measured environmental gradients. Spearman’s correlation analysis also showed that soil organic carbon, pH, available phosphorus, aggregate stability, and bulk density were significantly correlated with AMF community structure parameters.

Perubahan penggunaan lahan merupakan salah satu bentuk gangguan antropogenik yang dapat mengubah karakteristik tanah, komposisi vegetasi, dan kondisi habitat organisme tanah. Perubahan penggunaan lahan turut memengaruhi struktur komunitas mikroorganisme tanah, termasuk fungi mikoriza arbuskular (FMA), yang berperan dalam penyerapan unsur hara, pembentukan agregat tanah, serta meningkatkan ketahanan tanaman terhadap cekaman lingkungan. Struktur komunitas FMA dipengaruhi oleh interaksi berbagai faktor, terutama karakteristik tanah, vegetasi, dan penggunaan lahan. Informasi mengenai hubungan ketiga faktor tersebut pada kawasan Taman Hutan Raya Wan Abdul Rachman (Tahura WAR) Lampung masih terbatas sehingga diperlukan penelitian untuk mendeskripsikan struktur komunitas FMA pada tiga tipe penggunaan lahan serta hubungannya dengan karakteristik tanah. Penelitian ini bertujuan mendeskripsikan karakteristik tanah, membandingkan struktur komunitas FMA, serta menjelaskan hubungan karakteristik tanah dengan komposisi genus dan parameter struktur komunitas FMA pada tiga tipe penggunaan lahan, yaitu agroforestri multistrata, agroforestri sederhana, dan semak belukar di Tahura WAR. Penelitian dilaksanakan pada Agustus-Desember 2025 di blok pemanfaatan Tahura WAR, Lampung, sedangkan analisis karakteristik tanah, isolasi dan identifikasi FMA, serta pengamatan kolonisasi akar dilakukan di Laboratorium Bioteknologi Tanah, Departemen Ilmu Tanah dan Sumberdaya Lahan, Fakultas Pertanian IPB dan Laboratorium Ilmu Tanah, Fakultas Pertanian, Universitas Lampung. Setiap tipe penggunaan lahan diwakili oleh satu plot berukuran 50 × 50 m yang terdiri atas tiga subplot berukuran 5 × 5 m. Sampel tanah dan akar diambil secara komposit pada kedalaman 0-20 cm di daerah perakaran tanaman. Parameter yang diamati meliputi karakteristik fisika dan kimia tanah, populasi spora, komposisi genus, indeks keanekaragaman Shannon Wiener, dan kolonisasi akar FMA. Analisis data dilakukan menggunakan Principal Component Analysis (PCA), Linear Mixed Model (LMM) yang dilanjutkan dengan Estimated Marginal Means (EMMs), Redundancy Analysis (RDA), dan korelasi Spearman. Hasil penelitian menunjukkan bahwa karakteristik tanah berbeda pada setiap tipe penggunaan lahan. Agroforestri multistrata memiliki kandungan C-organik, P-tersedia, dan stabilitas agregat yang lebih tinggi dibandingkan agroforestri sederhana dan semak belukar, sedangkan semak belukar dicirikan oleh bobot isi yang lebih tinggi. Analisis PCA mengindikasikan bahwa karakteristik tanah mampu membedakan ketiga tipe penggunaan lahan. Agroforestri multistrata berasosiasi dengan kondisi tanah yang memiliki C-organik, pH, P-tersedia, porositas, dan stabilitas agregat yang lebih tinggi, sedangkan semak belukar berasosiasi dengan bobot isi yang lebih tinggi. Agroforestri sederhana menempati posisi di antara kedua tipe penggunaan lahan tersebut. Komunitas FMA yang ditemukan terdiri atas delapan genus, yaitu Glomus, Acaulospora, Diversispora, Gigaspora, Septoglomus, Sclerocystis, Paraglomus, dan Funneliformis. Hasil LMM menunjukkan bahwa tipe penggunaan lahan berpengaruh terhadap keanekaragaman genus dan kolonisasi akar FMA, tetapi tidak berpengaruh terhadap populasi spora. Komunitas FMA didominasi genus Glomus dan Acaulospora berdasarkan kelimpahan relatif dan frekuensi kemunculan. Analisis RDA menunjukkan bahwa variasi komposisi genus FMA berkaitan dengan bobot isi, pH, C-organik, P-tersedia, P-total, dan stabilitas agregat tanah. Glomus dan Acaulospora berasosiasi dengan bobot isi, sedangkan Diversispora dan Paraglomus berasosiasi dengan pH, P-tersedia, dan stabilitas agregat. Funneliformis berkaitan dengan C-organik, P-total, dan P-tersedia, sedangkan Gigaspora, Septoglomus, dan Sclerocystis menunjukkan hubungan yang relatif lemah terhadap gradien lingkungan yang diamati. Analisis korelasi Spearman juga menunjukkan bahwa C-organik, pH, P-tersedia, stabilitas agregat, dan bobot isi berkorelasi signifikan dengan parameter struktur komunitas FMA.