LANDSCAPE STRUCTURE: PATCHES

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1 LANDSCAPE STRUCTURE: PATCHES Referensi: Forman & Godron (1986), Dramstad, Olson & Forman (1996) dan Farina (1998) Prof. Dr. HADI SUSILO ARIFIN Dr. SYARTINILIA Dr. KASWANTO PENGANTAR EKOLOGI LANSKAP (ARL 230) DEPARTEMEN ARSITEKTUR LANSKAP CONTENT 1. Patch Origins and Change 2. Patch Size 3. Patch Shape 4. Patch Number and Configuration 5. Additional sources What is Landscape Ecology?..focuses on (1) the spatial relationships among landscape elements, (2) the flows of energy, mineral nutrients, and species among the elements, and (3) the ecological dynamics of the landscape mosaic through time (Forman 1983) 1. PATCH ORIGINS AND CHANGE 1

2 PATCHES Obyek yang memiliki sifat seperti Patch, termasuk quilts (selimut), mosaics, tanah, bercak padadalmatian, dan awan diataslangit. Suatu permukaan area yang non linear yang berbeda penampilannya dari area sekitarnya. Bervariasi dalam ukuran, bentuk. tipe, heterogeneity, dan boundary characteristics. Sering dikeliling oleh MATRIX, yaitu area sekitar yang memiliki perbedaan struktur jenis atau komposisinya. BASIC CONCEPTS E.g. After big fire the blackened landscape Two separate fires had ignited i a single patch was blackened nearby, and an extensive fire had swept the area beyond. Unburned area a little swamp; a clearing and gazed at a patch of grain wave gently in the breeze Four types of patches, each with a fundamentally different origin. The small burned area was created by a local disturbance, fire. The little swamp resulted from wet soil The clearing resulted from cutting the vegetation and planting the crop The key CAUSATIVE MECHANISMS, or ORIGINS for these patches involved disturbance, environmental heterogeneity, and human planting. These patches for years to come, the differences in their SPECIES DYNAMICS would become still more evident succession PATCH TURNOVER, the rate at which patches appear and disappear DISTURBANCE PATCHES Disturbance of a small area in a matrix produced a Disturbance of a small area in a matrix produced a DISTURBANCE PATCH. Mud slides, avalanches, windstorms, ice storms, herbivore outbreaks, mammal trampling, and many other natural change give rise to patches Human activities also cause disturbance patches logging in forest, burning in grassland, and strip mining for surface coal or minerals. 2

3 Nickel Mining (Source: Y. Setiyadi, 2003) Coal Mining (Source: Y. Setiyadi, 2003) Penggundulan hutan akibat penambangan erosi dan lanskap yang tidak baik Source: HS Arifin (2003) WHAT HAPPENS WHEN AN AREA IS DISTURBED? The post disturbance species dynamics population sizes of many species change rapidly THE FIRST RESPONSE: Dropping sharply as a results of death or damage of individuals; id Certain species become locally extinct they disappear from the patch area; Some species normally survive and remain in lowered population sizes, or in dormant forms such as seeds, spore, eggs, or cysts. THE SECOND RESPONSE: another drastic change in population size of many of the surviving species number increase, often more than compensating for the initial loss of individuals. THE THIRD RESPONSE: in rapid order is immigration, the arrival of species previously absent (animals, seeds, spores) SUCCESSION or RECOVERY FROM DISTURBANCE INVOLVES ALL THREE PROCESSES Major population size change Extinctions Immigrations 3

4 ENVIRONMENTAL RESOURCE PATCHES The origin of each patch is due to the heterogeneous or patchy distribution in space of environmental resource water and soil for the plants, or water and flowers for the animal communities. In many cases the ECOTONE or overlap zone separating a patch from the matrix is commonly the case in disturbance caused d patches. Environmental Resource Patches: are relatively permanent and patch turnover is extremely low. INTRODUCED PATCHES When humans introduce organism to an area an introduced patch results PLANTED PATCHES people introducing plants: rice paddies, pine, golf courses, and arboreta, form planted patches in a matrix the species dynamics and patch turnover depend largely upon the maintenance activities of people. HOMES or HABITATIONS house, associated yard, courtyard, farm buildings, and immediate surroundings. Habitation ecosystem includes 4 types: people, introduced plants and animals, introduced pests, and immigrating native species. PATCH SIZE Land use what is the minimum patch size needed to accomplish a particular objective? What is the optimum patch th size? 2. PATCH SIZE The answers to these questions are crucial to the understanding and management of landscape. The primary characteristics considered are ecological: energy, mineral nutrients, and species. Others: the ability to operate planting and harvesting machinery, the distance to habitations and market, or topographic variation. 4

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6 EFFECT ON SPECIES Large islands have more species than small islands. Relationship between species diversity and island size is not linear, but CURVILINEAR. Mountainous islands have more species than flat island of the same size. Island with evidence of considerable human disturbance activity often have fewer species than those without such activity. The relationship plotted between increasing area and the number of species is called a SPECIES AREA CURVE TERRESTRIAL LANDSCAPE Patches in the landscape differ significantly from islands surrounded by water. Landscape patches may high average turnover rates, whereas island are essentially permanent. The landscape matrix often has extremely high heterogeneity. The landscape matrix may be used as a rest stop for many species moving between patches, particularly in the limited area of a landscape compared with the extensiveness of oceanic archipelagos. 3. PATCH SHAPE 6

7 Ukuran dan bentuk patch merupakan atribut penting yang mempengaruhi aliran (fluxes) abiotik dan biotik. Di alam umum dijumpai bentuk regular dan irregular. Semakin irregular semakin banyak edges yang tersedia. Hal ini mempunyai implikasi yang sangat besar terhadap penyebaran tanaman dan pergerakan hewan. Dengan menggunakan ratio L/2 A, di mana L = keliling patch dan A = luas, dimungkinkan untuk mengevaluasi jumlah dari edges. Lingkaran mempunyai ratio 1 dan menerangkan gambar geometrik dengan ratio minimum antara keliling dan area. NILAI NUMERIK JUMLAH PERIMETER, LUAS DAN EDGE DARI BERBAGAI BENTUK PATCH. 2 Patch Perimeter Area L/2VAπ , , , ,125 9, , Gambar bentuk dan ukuran patch 7

8 PATCH NUMBER AND CONFIGURATION 4. PATCH NUMBER AND CONFIGURATION Patches generally do not exist singly gy but are numerous in a landscape. A single large patch contains more species than several smaller patches. More species are found in several patches if the patches are widely scattered. 8

9 LANSKAP DAN KOMPONENNYA (PATCHES) DAPAT DIKLASIFIKASIKAN DENGAN PENDEKATAN ANTHROPOCENTRIC, ATAU DENGAN PENDEKATAN YANG TERGANTUNG PADA KAPASITAS PENGAMATAN KITA: 1. STRUCTURAL PATCH 2. FUNCTIONAL PATCH 3. RESOURCE PATCH 4. HABITAT PATCH 5. CORRIDOR PATCH 9

10 Stucture patch: secara umum terdiri dari satu tipe tanah yang dioverlap oleh asosiasi vegetasi Fungsional patch: suatu area yang homogen untuk satu fungsi atau satu pendeskripsian fisik, seperti altitude, temperatur, kelembaban, penetrasi cahaya. Resource patch: sebagian besar berhubungan dengan ekologi hewan; suatu lanskap dapat diuraikan sebagai satu kombinasi dari beberapa resource patches bagian dari home range hewan (pakan, tempat bersarang tersedia dengan gampang). See Fig Habitat patch: dapat didefinisikan sebagai tipe komunitas tanaman tertentu yang secara umum lebih besar dari pada home range individu. Corridor patch: sebagai satu bagian dari mosaik lahan yang digunakan oleh organisme untuk pindah/bergerak, menjelajah, menyebar dan migrasi. 10

11 Klasifikasi adalah suatu prosedur yang relevan di dalam studi land mosaic, khususnya seperti yang diketahui untuk perspektif manusia. Pendekatan ini umumnya digunakan oleh ahli ekologi lanskap yang tertarik dalam studi interaksi antara aktivitas manusia dan lanskap. Khususnya berguna untuk persiapan master plan, perencanaan nature reserve, dan secara umum sebagai panduan pada beberapa tipe manajemen lanskap. Tidak ada aturan yang pasti, tetapi perubahannya sesuai dengan tujuan, skala investigasi, waktu dan ketersediaan sumber daya finansial. Sejumlah informasi diperlukan untuk memproduksi kalsifikasi yang baik dan berguna. Sumber-sumber utama : foto udara, citra landsat (satelite digital images), cadastral maps, peta-peta geologi, hidrologi dan tanah, peta-peta geografi dan biotematik (vegetasi, land use, distribusi hewan). Contoh klasifikasi lanskap di Belanda berdasarkan pada hirarki wilayah hidrologis, geomorfologis dan struktur vegetasi 11

12 PHYSIOTOPE Unit spatial yang dicirikan oleh faktor-faktor keadaan abiotik yang relatif homogen. Physiotope secara umum diklasifikasikan dengan menggunakan geologi, aspek dan slope rate (tingkat kemiringan). Physiotope merupakan dasar untuk klasifikasi lanskap lebih lanjut. Klasifikasi secara hierarchi pada level yang terendah kita ketahui : physiotope, kemudian ecotope, land unit, land system. (meskipun pada beberapa kasus physiotope dapat lebih besar daripada ecotope). ECOTOPE Unit lahan yang terkecil yang masih merupakan suatu unit yang holistik. Ecotope memperlihatkan dimensi topologi suatu lanskap. Physiotope Ecotope Land Unit Land System. Contact Address: [email protected] FB Regan Leonardus Kaswanto Setiap pengambilan material, copy & paste sebagian atau keseluruhan material ini harap mensitasi sumber dan mencantumkan link blog. Terima kasih 12