FIELD OBSERVATIONS ON TIDAL TRANSPORT OF ORGANIC MATERIALS AND NUTRIENTS IN MANGROVE AREA

Kawasan mangrove dapat memproduksi bahan organik dari proses dekomposisi serasah yang jatuh yang menjadi penyuplai nuterien ke lingkungannya. Proses tersebut menggunakan oksigen terlarut yang apabila oksigen terlarut habis maka proses tersebut beralih ke proses dekomposisi secara anaerob yang menyebabkan terbentuknya senyawa H2S. Penelitian ini bertujuan untuk mengetahui perbedaan kandungan bahan organik sedimen dan kadar H2S air di dalam dan di luar kawasan mangrove serta untuk mengetahui hubungan kandungan kadar H2S air dengan bahan organik sedimen dan oksigen terlarut di kawasan mangrove desa Bedono. Metode penelitian adalah metode survey. Penelitian ini dilakasanakn pada bulan Mei- Juni 2017 di lokasi yang mewakili kawasan mangrove dan lingkungan sekitarnya. Data yang diukur adalah suhu air, kecerahan, kedalaman, kecepatan arus, oksigen terlarut, pH, bahan organik sedimen dan H2S air yang dilaksanakan empat kali dengan selang pengukuran dua minggu. Hasil yang didapat yaitu suhu air 28-31oC, kecerahan 14,5-68 cm, kedalaman 33-165 cm, kecepatan arus 0-0,1 m/s, oksigen terlarut , pH 5-6, bahan organik sedimen 7,73-20,27%, H2S air 0,003-0,037 mg/l. Kandungan bahan organik sedimen dan kadar H2S air tertinggi di dalam kawasan mangrove dengan rata-rata 16,36% dan 0,031 mg/l, dan terendah di luar kawasan mangrove dengan rata-rata 9,78% dan 0,01 mg/l. Kadar H2S tinggi di dalam kawasan mangrove dan lebih rendah di luar kawasan mangrove. Kadar H2S air dengan bahan organik sedimen dan oksigen terlarut berhubungan linier dengan persamaan H2S= 0,027 + 0,001BOS- 0,006 DO (r= 0,7246, BOS= Bahan Organik Sedimen, DO= Dissolved Oxygen). Mangroves produce organic matter from the decomposition of falling leaves, twigs etc, which supply nutrient to the environment. The process uses dissolved oxygen; when dissolved oxygen exhausted, it switches into anaerobic decomposition which causes the formation of H2S compounds. This study aims to knowing differences in sediment organic materials and H2S within and adjacent of mangrove areas and to determine the relation of H2S with sediment organic materials and dissolved oxygen in the mangrove areas of Bedono. Survey method is refered, and the study was conducted in May - June 2017 on locations representing mangrove areas and the surrounding environment. The data measured are water temperature, brightness, depth, current speed, dissolved oxygen, pH, sediment organic materials and H2S in the water. Sampling was conducted four times every fortnight. The result of the water temperature is 28-31 ° C, brightness 14.5 to 68 cm, 33-165 cm depth, current speed 0-0.1 m/s, dissolved oxygen 2-5,2 mg/l, pH 5-6, sediment organic material 7,73 to 20.27%, H2S 0.003 to 0.037 mg/l. Sediment organic materials and H2S were highest within the mangrove area, with an average 16.36% and 0.031 mg/l, and the lowest outside of mangrove area with an average 9.78% and 0.01 mg/l. H2S higher in the inside of the mangrove areas compared to the outside of it. The relation of H2S with sediment organic materials and dissolved oxygen is linearly related according to the equation H2S= 0.027+ 0.001SOM- 0.006DO (r= 0.7246, SOM= Sediment Organic Materials, DO= Dissolved Oxygen).

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Estimasi Cadangan Karbon pada Kawasan Mangrove di Desa Timbulsloko, Demak, Jawa Tengah

BULETIN OSEANOGRAFI MARINA ◽

10.14710/buloma.v7i2.19574 ◽

2018 ◽

Vol 7 (2) ◽

pp. 121

Author(s):

Wiwid Andriyani Lestariningsih ◽

Nirwani Soenardjo ◽

Rudhi Pribadi

Keyword(s):

Climate Change ◽

Carbon Stock ◽

Organic Materials ◽

Plant Biomass ◽

Mangrove Ecosystem ◽

Carbon Stocks ◽

The Body ◽

Body Parts ◽

Purposive Sampling ◽

Mangrove Area

Ekosistem mangrove merupakan salah satu ekosistem yang berperan dalam mengurangi karbon di udara, dan menyimpan karbon dari udara dalam bentuk biomassa pada bagian tubuh tumbuhan mangrove. Penelitian tentang estimasi cadangan karbon ini sangat diperlukan untuk menunjang perbaikan iklim dunia. Karena saat ini dunia sedang mengalami krisis global yang disebut climate change. Tujuan penelitian ini adalah mengestimasi cadangan karbon yang tersimpan pada tegakan dan substrat mangrove di kawasan mangrove Desa Timbulsloko. Metode yang digunakan yaitu purposive sampling method dan eksploratif, dilakukan di tiga stasiun dengan kondisi ekosistem mangrove yang bervariasi. Setiap stasiun penelitian dibagi menjadi tiga plot penelitian untuk menghitung nilai biomassa tegakan digunakan rumus allometrik untuk mengestimasi cadangan karbon pada tegakan mangrove. Data karbon substrat didapat dari kandungan bahan organik substrat yang dianalisis di Laboratorium. Berdasarkan hasil penelitian, diketahui bahwa cadangan karbon pada tegakan mangrove sebesar 12.370,8 ton/ha, sedangkan estimasi cadangan karbon pada substrat mangrove sebesar 1.307,77 ton/ha. Hasil tersebut menunjukkan bahwa estimasi cadangan karbon pada tegakan mangrove lebih besar dibandingkan dengan estimasi cadangan karbon pada substrat mangrove. Hasil estimasi cadangan karbon pada tegakan mangrove meningkat seiring dengan meningkatnya besarnya biomassa tumbuhan dan kerapatan mangrove. Sedangkan estimasi cadangan karbon pada substrat diduga lebih dipengaruhi oleh bahan organik dan lokasi penelitian. Estimates of Carbon Stok in the Mangrove Area in Timbulsloko Village,Demak, Central Java Mangrove ecosystem is one of the ecosystem that play a role in reducing carbon in the air. One of the functions of mangrove is to store carbon from the air form of biomass in the body parts of mangrove plants. This research on the estimation of carbon stocks is needed to support the improvement of world climate. Today the world is experiencing a global crisis called climate change. The purpose of this research are estimate of carbon stock on stands and substrate in mangrove area of Timbulsloko Village. This research used purposive sampling and explorative method, conducted in three stations with varying mangrove ecosystem conditions. The research was divided into three research plots per station to calculate the stand biomass value using allometric formula in estimating carbon stocks of mangrove area. Substrate carbon data obtained from the content of substrate organic materials analyzed at Laboratorium. Based on the result of research, it is found that carbon stock in mangrove stands is 12.370,8 ton/ha, while estimation of carbon stock on mangrove substrate is 1.307 ton/ha. These results show that estimates of carbon stocks in mangrove stands are greater than estimates of carbon stocks on mangrove substrates. The estimation of carbon stocks on mangrove stands increases with increasing of plant biomass and mangrove density, while estimates of carbon stocks on the substrate are suspected to be more influenced by organic materials and research sites.

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Application of Improved Voltage Compensation in the SEM to Imaging of Organic Materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072666 ◽

1973 ◽

Vol 31 ◽

pp. 444-445

Author(s):

P.J. Killingworth ◽

M. Warren

Keyword(s):

Electron Beam ◽

Organic Materials ◽

Operating Parameters ◽

Low Density ◽

Beam Diameter ◽

Incident Electron Beam ◽

Specimen Material ◽

Voltage Compensation ◽

Selection Of ◽

Scanning Electron

Ultimate resolution in the scanning electron microscope is determined not only by the diameter of the incident electron beam, but by interaction of that beam with the specimen material. Generally, while minimum beam diameter diminishes with increasing voltage, due to the reduced effect of aberration component and magnetic interference, the excited volume within the sample increases with electron energy. Thus, for any given material and imaging signal, there is an optimum volt age to achieve best resolution.In the case of organic materials, which are in general of low density and electric ally non-conducting; and may in addition be susceptible to radiation and heat damage, the selection of correct operating parameters is extremely critical and is achiev ed by interative adjustment.

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200kv superconducting cryo electron microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100127645 ◽

1987 ◽

Vol 45 ◽

pp. 642-643

Author(s):

M. Iwatsuki ◽

Y. Kokubo ◽

Y. Harada ◽

J. Lehman

Keyword(s):

Electron Microscope ◽

Structure Analysis ◽

Organic Materials ◽

Strong Interactions ◽

Specimen Preparation ◽

Great Effort ◽

Electron Microscopic ◽

Crystal Fields ◽

Special Skill ◽

Long Time

In recent years, the electron microscope has been significantly improved in resolution and we can obtain routinely atomic-level high resolution images without any special skill. With this improvement, the structure analysis of organic materials has become one of the interesting targets in the biological and polymer crystal fields.Up to now, X-ray structure analysis has been mainly used for such materials. With this method, however, great effort and a long time are required for specimen preparation because of the need for larger crystals. This method can analyze average crystal structure but is insufficient for interpreting it on the atomic or molecular level. The electron microscopic method for organic materials has not only the advantage of specimen preparation but also the capability of providing various information from extremely small specimen regions, using strong interactions between electrons and the substance. On the other hand, however, this strong interaction has a big disadvantage in high radiation damage.

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STM of freeze-fracture replicas: Problems and promises

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146187 ◽

1993 ◽

Vol 51 ◽

pp. 68-69

Author(s):

J. T. Woodward ◽

J. A. N. Zasadzinski

Keyword(s):

Scanning Tunneling Microscope ◽

Organic Materials ◽

Freeze Fracture ◽

Atomic Resolution ◽

Scanning Tunneling ◽

Tunneling Microscope ◽

Molecular Scale ◽

Organic Surfaces ◽

Metal Layers ◽

Conductive Surfaces

The Scanning Tunneling Microscope (STM) offers exciting new ways of imaging surfaces of biological or organic materials with resolution to the sub-molecular scale. Rigid, conductive surfaces can readily be imaged with the STM with atomic resolution. Unfortunately, organic surfaces are neither sufficiently conductive or rigid enough to be examined directly with the STM. At present, nonconductive surfaces can be examined in two ways: 1) Using the AFM, which measures the deflection of a weak spring as it is dragged across the surface, or 2) coating or replicating non-conductive surfaces with metal layers so as to make them conductive, then imaging with the STM. However, we have found that the conventional freeze-fracture technique, while extremely useful for imaging bulk organic materials with STM, must be modified considerably for optimal use in the STM.

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Stabilizing pyritic material

The Paleontological Society Special Publications ◽

10.1017/s2475262200005207 ◽

1989 ◽

Vol 4 ◽

pp. 244-248 ◽

Cited By ~ 2

Author(s):

Donald L. Wolberg

Keyword(s):

Significant Contribution ◽

Organic Materials ◽

Sedimentary Rocks ◽

Iron Sulfides ◽

Decomposition Products ◽

Iron Minerals ◽

Pyrite Formation ◽

Organic Sediments ◽

Freshwater Environments

The minerals pyrite and marcasite (broadly termed pyritic minerals) are iron sulfides that are common if not ubiquitous in sedimentary rocks, especially in association with organic materials (Berner, 1970). In most marine sedimentary associations, pyrite and marcasite are associated with organic sediments rich in dissolved sulfate and iron minerals. Because of the rapid consumption of sulfate in freshwater environments, however, pyrite formation is more restricted in nonmarine sediments (Berner, 1983). The origin of the sulfur in nonmarine environments must lie within pre-existing rocks or volcanic detritus; a relatively small, but significant contribution may derive from plant and animal decomposition products.

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