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"The problem of eutrophication and its factors become one of the major water quality problems. In the USA the problem over one half of the surface water supplies are due to excessive growth of aquatic plants. Other consequences are the decline in suitability of the water for industrial and water supply, and a general loss of attractiveness from the recreational point of view. Those problems appear due to the development of weeds and scummy blooms of blue green algae anabaena. Many of these algae produce unpleasant odor and tastes. The worst thing in eutrophication is that the change seems to be irreversible. Sudden appearances of bloom in lake are generally human activities responsibility."

"The Biology of Lakes and Ponds focuses on the interactions between the abiotic frame, such as turbulence, temperature, pH and nutrients, and the organisms, including interactions with and among organisms at the individual, population and community level. The book fills this niche between traditional limnology and evolutionary ecology by focusing on physiological, morphological and behavioural adaptations among organisms to abiotic and biotic factors and how interactions between biotic processes and abiotic constraints determine the structure and dynamics of lake and pond systems. In addition, the book describes and analyses the causes and consequences of human activities on freshwater organisms and ecosystems and covers longstanding environmental threats, such as eutrophication and acidification, as well as novel threats, such as biodiversity loss, use of everyday chemicals and global climate change. However, also signs of improvement and the possibilities to restore degraded ecosystems are discussed and provide hope for future generations."

"ABSTRAKJenis penelitian ini adalah etnografi yang berfokus pada aktivitas pemanfaatan ekosistem danau dan bentuk-bentuk kebijakan pengelolaan yang ditetapkan oleh pemerintah dan kelembagaan adat. Teknik pengumpulan data adalah studi pustaka, observasi partisipasi, dan wawancara mendalam. Lokasi penelitian meliputi empat wilayah kecamatan yang memiliki wilayah danau terluas yakni Kecamatan Tempe, Kecamatan Sabbang Paru, Kecamatan Tanasitolo Dan kecamatan Belawa. Informan adalah masyarakat sekitar danau, tokoh adat, serta kepala dan staf SKPD yang terkait dengan manajemen danau. Penelitian ini menemukan Danau Tempe menjadi sumber daya milik bersama (common property resources) karena dapat dimanfaatkan dan diakses secara bersama oleh semua orang tanpa batasan yang tegas. Bentuk kebijakan pengelolaan danau dirancang dan dibuat oleh pemerintah dan lembaga adat lokal. Bentuk kongkrit kebijakan pengelolaan danau, dijabarkan dalam peraturan daerah serta dalam bentuk system norma, upacara adat dan pamali-pamali, yang pengawasannya dilakukan oleh pembuat kebijakan, serta masyarakat. Secara de yure, Danau tempe dikelola secara kolaborasi (collaborative management ) antara pemerintah dengan lembaga adat, namun secara de facto, fungsi manajemen kolaborasi tidak optimal sehingga Danau Tempe tampak seperti sumber daya yang bisa diakses oleh siapa saja, tanpa aturan ( open access )

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ABSTRACTThis research is a ethnography type that focused to the activity of lake ecosystem and forms of management policies set by governments and traditional institutions. The data collection technique is literature, participant observation and deep interviews. Research Location covers four regions districts that had the largest lake district area of Tempe, District Sabbangparu, district Tanasitolo and district Belawa. Informants are people around the lake, traditional leaders and also the heads and staff SKPD who related to lake management. This study found that the lake Tempe as be a common property resources (common property resources) because it can be shared and utilized by all people without clear limits. Forms of lake management policy is designed and made by local government and traditional institutions. Concrete forms of lake management policy, spelled out in local legislation as well as in the form of system norms, ceremonies and taboos-taboos, the monitoring carried out by policy makers and the public. In de yure, Tempe Lake managed in collaboration between the government and indigenous institutions (collaborative management), but de facto, collaboration management functions are not optimal so Tempe lake looks like resources that can be accessed by anyone, without rules (open access) "

"ABSTRAKDalam bidang geologi dan geofisika, pendeteksian, identifikasi sertapengkualifikasian batuan reservoir berdasarkan parameter berupa ketebalan, porositas dan kandungan fluida menggunakan data seismic refleksi merupakan hal yang sangat krusial. AVO dan inversion merupakan metoda yang berguna dalam membedakan batuan reservoir dengan kandungan hidrokarbon dari batuan lain disekitarnya. Batupasir yang memiliki kandungan gas, umumnya dicirikan olehkontras impedance yang relatif besar dibandingkan batuan di sekitarnya. Kombinasi antara data seismik, pemodelan langsung baik sebelum atau sesudah stack ditambah dengan informasi yang diperoleh dari sumur pemboran akan mempermudah proses penarikan kesimpulan berkaitan dengan distribusi penyebaran reservoir disertai perubahan yang terjadi pada parameter - parameter reservoir itu sendiri ; misalnya variasi tebal bersih kolom gas, tebal bersih reservoir/tebal bersih porositas.Pada daerah studi lapangan Blackfoot, dilakukan perhitungan rasio AI, EI dan ?Mu-Rho? dengan tujuan menentukan jenis unit litologi. Hal ini dapat dilakukan dengan memanfaatkan hasil perhitungan even P-P dan P-S yang diperoleh dari data sonic. Korelasi yang diperoleh antara data log sumur dengan even seismik, didukung oleh rasio AI, EI dan ?Mu-Rho? memperlihatkan bahwa perubahan nilai Impedansi akustik, EI dan ?Mu-Rho?dapat dikaitkan secaralangsung dengan rasio sand/shale dan tingkat konsolodasi batuan sedimen baik secara lateral maupun vertikal. Hasil analisis menunjukkan bahwa batuan reservoir yang berkembang dilapangan Blackfoot adalah batupasir glaukonit yang diendapkan pada lingkungan incised valley. Dalam seismic dapat dikenali melalui kedalamannya yang relatif dangkal (1500-1600 m), nilai porositas yang tinggi (15-26%), ketebalan batupasir dibawah tuning ( kurang dari 20 m) serta adanya anomali amplitudo yang tinggi (bright spot). Secara umum, glauconitic channel sand produk dari incised valleypada lapangan Blackfoot memiliki karakter berupa nilai rasio Vp/Vs yang rendah, nilai P ? Impedance dan S ? Impedance yang rendah, Elastik Impedance yang rendah, nilai Mu ? Rho yang tinggi dan nilai Lambda ? Rho yang rendah.

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ABSTRACTThe detection, identification, and qualification of thickness, porosity, and fluid content in reservoirs rocks, using seismic reflection data, is a very important topic in the area of geology and geophysics. AVO and Inversion method is gained to identify the reservoirs that contain hydrocarbon. For the gas sands has relatively strong contrast between the elastic properties of these and those of thesurrounding rocks is expected, the detection and qualification depends upon many other factors: degree of consolidation, ratio depth/thickness, lithologies involve, clay content, etc. The integration of seismic data with direct modeling, both before and afterstack, and with well information, allowed us to draw important conclusions regarding reservoirs extensions, as well as changes in other properties (net gas thickness in one case, and net sand thickness/net porosity thickness for the other) which are important for advanced development of these fields. Using the interpreted correlations the interval times of P-P and P-S events were used to calculate AI, EI, ?Mu-Rho? ratio for the principal lithologic units inBlackfoot area. Well log correlations to seismic events and AI, EI, ?Mu-Rho? ratio data indicate that changes in AI, EI, ?Mu-Rho? can be directly related to changes in the sand/shale ratio and the consolidation state of the sediments both laterally and vertically in the section. The AI ratio as the function of P-Impedance and S-Impedance correlatewith Elastic Impedance of the reservoirs properties and ?Lambda-Mu-Rho?are giving the best result to determine the lithology and fluid contents. In this seismic perspective, I considered with glauconitic incised valley sands. At Blackfoot filed, which is characterized by shallow depth (1500-1600 m), high porosities (15-26 %), sand thickness below tuning (less than 20 m), and where the reservoirs show as high amplitude anomalies (bright spot).In the Blackfoot area, the productive glauconitic incised valley sands can be identified by Vp/Vs ratio at the low value, P-Impedance and S-Impedance at low value, Elastic Impedance at the low value, Mu-Rho at the high value and Lambda-Rho at the low value."

"Penelitian Tesis ini dilakukan pada reservoar batupasir MX dari Formasi Pematang Lapangan M Cekungan Sumatera Tengah. Tujuan penelitian ini adalah untuk menentukan metode geofisika yang tepat untuk karakterisasi reservoar batupasir yang keras (tight), membangun model properti reservoar, menghitung sumberdaya minyak yang terkandung dan menentukan usulan titik sumur pengembangan. Reservoar batupasir Formasi Pematang dikategorikan sebagai batupasir keras karena nilai porositas dan permeabilitas yang cukup rendah (permeabilitas 8 mD) sehingga Metode Inversi Acoustic Impedance (AI) kurang representatif untuk menyebarkan facies reservoar tersebut. Hal ini dikarenakan nilai AI reservoar masih tumpang-tindih dengan nilai AI litologi non-reservoar. Selain itu, secara geologi Formasi Pematang cukup kompleks dari sudut pandang stratigrafi dan struktur. Oleh karena itu, dilakukan analisa cross-plot data elastisitas batuan: data Lamda-Rho, Mu-Ro, Lamda-Mu, Gamma Ray dan Poisson Impedance (PI). Dari crossplot tersebut beberapa parameter elastik batuan dapat diterapkan untuk karakterisasi tight reservoir seperti Mu-Rho, PI dan Gamma Ray. Namun demikian penelitian ini fokus pada Metode PI sebagai metode penyebaran reservoar karena nilai PI 9500-9899 (ft/s*g/cc) berhasil digunakan sebagai pemisah (cut-off) reservoar pada hasil inversi data seismik 3D. Hasil Inversi PI dijadikan sebagai masukan dalam pembuatan model facies geologi dan trend control pembuatan model properti. Kemudian, dilakukan pemodelan properti reservoar misalnya model porositas, model NTG dan model saturasi air dengan Pendekatan Geostatistik dengan data masukan hasil analisa petrofisika sumur. Hasil penelitian menyimpulkan bahwa reservoar MX diendapkan pada lingkungan fluvial delta plain debris bagian dari lingkungan danau purba dan sumberdaya minyak yang terkandung sebanyak 26.78 MMstb. Usulan lokasi sumur pengembangan sebaiknya diletakkan di sekitar lokasi sumur M#2 yaitu di bagian BaratLaut dan Tenggara dari lokasi sumur M#2 agar sumur pengembangan tersebut berhasil menemukan minyak.

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Thesis research was performed at MX sandstone of Pematang Formation in the M Field, Central Sumatera Basin. The objectives of the research are to find applicable geophysics method to characterize tight sandstone reservoir, build reservoir property models, calculate oil resources and determine development well locations. Pematang Formation sandstone reservoir is categorized as tight sandstone since its porosity and permeability (8 mD) value is low, hence Acoustic Impedance Inversion (AI) is not representative for sand distribution. It is caused by overlapping value of AI between tight sands and its shale lithology. Additionally, the Pematang Formation is quite complex in term of stratigraphy and structure. Therefore, it was conducted reservoir elastic properties: Lamda-Rho, Mu-Rho, Lamda-Mu, Gamma-ray and Poisson Impedance. Based on the cross-plot some those properties can be applied for the oil tight sand characterization like PI, Mu-Rho and Gamma-ray. Nevertheless, the research chose PI Method as a tool to distribute tight sand with PI cut-off 9500-9899 (ft/s*g/cc). This value was implemented into 3D seismic data for tight sand facies mapping. The result of PI was dedicated as an input for facies modeling and a trend control in creating property model. Then, reservoir properties were modeled using Geostatistic Method to create porosity, NTG and water saturation model with input from petrophysic analysis. Result of the study concludes that the MX reservoir was deposited as a fluvial delta plain debris of paleo-lacustrine and has oil resources, is about 26.78 MMstb. Development wells location proposal should consider this input and put wells nearby M#2 well location namely at NorthWest and SouthEast from M#2 well location in order to get successful drilling."