Aplikasi Data Penginderaan Jauh Untuk Kajian Kondisi Eksisting Ekosistem Mangrove di Wilayah Kepesisiran Kecamatan Pantai Labu, Kabupaten Deli Serdang, Sumatera Utara

Penelitian ini dilaksanakan di wilayah kepesisiran Kecamatan Pantai Labu, Kabupaten Deli Serdang, Sumatera Utara. Penelitian ini bertujuan untuk mengetahui kondisi eksisting, mengetahui indeks keanekaragaman, dan mengetahui agihan ekosistem mangrove yang tumbuh di wilayah kepesisiran Kecamatan Pantai Labu. Penelitian ini menggunakan metode survei. Metode pengumpulan data dengan sampling serta metode analisisnya secara kualitatif. Populasi dari penelitian ini adalah seluruh ekosistem mangrove yang terdapat di daerah penelitian. Teknik pengambilan sampel dengan cara purposive sampling untuk penentuan transek garis dan petak contoh (transect line plot). Teknik pengumpulan data meliputi analisis data sekunder, observasi, dan perhitungan langsung di lapangan. Variabel penelitian ini meliputi kerapatan (densitas), kekerapan (frekuensi), luas penutupan (coverage), indeks nilai penting (importance value index), indeks dominasi (index of dominance), dan indeks keanekaragaman (diversity). Teknik analisis hasil menggunakan analisis spasial dan analisis deskriptif. Hasil penelitian menunjukkan kondisi eksisting ekosistem mangrove yang terdapat di Kecamatan Pantai Labu berdasarkan hasil interpretasi visual citra Google Earth Tahun 2015 sebesar 517,95 ha. Keanekaragaman vegetasi mangrove di Kecamatan Pantai Labu memiliki indeks keanekaragaman H’ < 1,0. Artinya keanekaragaman mangrove di Kecamatan Pantai Labu masih rendah, miskin, produktivitas sangat rendah sebagai indikasi adanya tekanan yang berat, dan ekosistem tidak stabil. Spesies mangrove yang terdapat di Kecamatan Pantai Labu meliputi Avicennia sp (api-api), Rhizophora sp (bakau), Sonneratia sp (pedada), Bruguira sp, dan Xylocerpus sp (nyirih). Persebaran dan agihan ekosistem mangrove di Kecamatan Pantai Labu berada di sepanjang tepi pesisir yang meliputi Desa Sungai Tuan dengan luas 128,58 ha, Desa Bagan Serdang dengan luas 78,75 ha, Desa Regemuk dengan luas 33,50 ha, Desa Pantai Labu Pekan dengan luas 15,85 ha, Desa Paluh Sebaji dengan luas 73,48 ha, dan Desa Denai Kuala dengan luas 187,79 ha. Kata Kunci: ekosistem mangrove, wilayah kepesisiran, Google Eart

KONSTELASI KERUANGAN BIARA SANGKILON, KAWASAN KEPURBAKALAAN PADANG LAWAS BAGIAN SELATAN PADA ABAD XI—XIV MASEHI

Biara Sangkilon is one of the many biaras in the in Padang Lawas archaeological area located in Sangkilon Village, Lubuk Barumun District, Padang Lawas Regency. In general, the arrangement of biaras in this region has its own characteristics, namely the main building facing the mandapa, with one gate. The problem raised in this paper is how the spatial constellation of Biara Sangkilon is? The writing purpose of this article is to get a description of the space boundaries based on the distinction of spatial functions and their relationships in the Biara Sangkilon Complex. Through descriptive-analytical research it can be seen in fact through the form of structure, distance, findings artifactual, and boundaries, there is a fairly clear division of space between sacred space, and profane at Biara Sangkilon. Biara Sangkilon merupakan salah satu dari sekian banyak biara di Kawasan Kepurbakalaan Padang Lawas yang terletak di Desa Sangkilon, Kecamatan Lubuk Barumun, Kabupaten Padang Lawas. Secara umum, susunan biara-biara yang terdapat di kawasan ini memiliki ciri khas tersendiri yaitu bangunan utama berhadapan dengan mandapa, dengan satu pintu gerbang. Adapun permasalahan yang diangkat dalam makalah ini adalah bagaimanakah konstelasi keruangan Biara Sangkilon? Tujuan dari penulisan artikel ini untuk mendapatkan gambaran tentang batas-batas ruang yang didasarkan pada pembedaan fungsi-fungsi ruang beserta relasirelasinya yang terdapat di Kompleks Biara Sangkilon. Melalui penelitian yang bersifat deskriptifanalitis dapat diketahui ternyata melalui bentuk struktur, jarak, temuan artefaktual, dan batasbatas, terdapat pembagian ruang yang cukup jelas antara ruang sakral, dan profan di Biara Sangkilon.

To What Extent Is Hydrologic Connectivity Taken into Account in Catchment Studies in the Lake Tana Basin, Ethiopia? A Review

Knowledge of hydrologic connectivity is important to grasp the hydrological response at a basin scale, particularly as changes in connectivity can have a negative effect on the environment. In the context of a changing climate, being able to predict how changes in connectivity will affect runoff and sediment transport is particularly relevant for land-use planning. Many studies on hydrology, geomorphology and climatology have been conducted in the Lake Tana Basin in Ethiopia, which is undergoing rapid development and significant environmental changes. This systematic literature review aims at assessing to what extent the hydrologic connectivity has been taken into account in such research, and to identify research gaps relevant to land and water management. On the Web of Science and Scopus databases, 135 scientific articles covering those topics were identified. Aspects of hydrologic connectivity were mostly implicitly taken into account based on process-based, statistical and descriptive models. Amongst the drivers of changing connectivity, the climate was covered by a large majority of publications (64%). Components of structural hydrologic connectivity were accounted for by considering geomorphology (54%) and soils (47%), and to a lesser extent, hydrography (16%) and geology (12%). Components of functional connectivity were covered by looking at surface water fluxes (61%), sediment fluxes (18%) and subsurface water fluxes (13%). While numerous studies of the Lake Tana Basin accounted for the hydrologic connectivity implicitly, these related predominantly to functional components. The structural components are given less attention, while in the context of a changing climate, better insights into their influence on the hydrologic seem most relevant. Better knowledge of the static aspect of connectivity is particularly important for targeting appropriate soil and water conservation strategies. Being able to explicitly assess the ‘structural connectivity’ is therefore of direct relevance for land management and land-use policy