7/18/16
An Introduction Ocean Remote Sensing Second edition
An introduction to ocean remote sensing (2nd ed.) [s. martin, 2014] from Marchel Monoarfa
http://www.slideshare.net/marchmono/an-introduction-to-ocean-remote-sensing-2nd-ed-s-martin-2014TEST FUNCTION FORAMINIFERA (FUNGSI TEST/CANGKANG FORAMINIFERA)
TEST FUNCTION FORAMINIFERA
(FUNGSI TEST/CANGKANG
FORAMINIFERA)
 |
| Operculina ammonoides (Source: Marchel Monoarfa ) |
The evolutionary and ecological success
of Foraminifera depends in part on the functional significance of the test.
However, some agglutinated Foraminifera can live as naked organisms outside the
test (Astrorhiza limicola: Schultz, 1915; Buchanan and Hedley, 1960;
Christiansen, 1971; Cedhagen, 1988; Iridia: Cushman, 1922; Astrammina rara:
Bowser and Delaca, 1985). Such forms may be in between growth stages for when
they are supplied with detrital material, Astrammina soon makes a new test.
Indeed, Cedhagen and Tendal (1989) suggest that juveniles of this species
smaller than 1.5mm in size might live without a test. Individuals of Astrammina
rara from which the test was experimentally removed soon formed a new one
(Bowser et al.,
1995).
There are morphological features of the
test that may be of functional importance (see reviews by Hallock et al., 1991
and Hottinger, 2000) but experimental evidence supporting functional interpretations
of specific morphological features is still very sparse. Six possible functions
for the test as a whole have so far been proposed although, as discussed below,
the results areinconclusive (Marszalek et al., 1969; Murray, 1991).
1.
To provide shelter. The test gives protection against unfavourable environmental conditions
and, in addition, some species close their test openings for several hours by
sealing them with debris. The organic lining of calcareous tests is the ultimate
defence against low pH as Bradshaw (1961) showed that Ammonia ‘beccarii’
survived pH 2.0 for 111 4 h even though dissolution of the test took place.
Spirillina vivipara, which lacks an organic lining, did not survive. Marszalek
et al. speculated that chambered tests, such as that of Quinqueloculina, would
give protection against sudden osmotic changes but this was shown by experiment
not always to be true (Murray, 1968a). There may be some protection against
certain wavelengths of light in shallow waters (Haynes, 1965; Banner and
Williams, 1973).
2.
To serve as a receptacle for excreted matter. There are two aspects to excretion. It is known that
some foraminifera store the waste products (stercomata or xanthosomes) in their
test (Tendal, 1979). However, others consider that the test itself may be a
consequence of excretion (e.g., the organic lining: Banner et al., 1973; or
removal of toxic Ca2รพ, Brasier, 1986).
3.
To aid reproduction. There is no direct evidence that the test is of particular use during
reproduction (except that some parent tests are partially dissolved to supply
material for the offspring).
4.
To control buoyancy. It is likely that the density of the soft parts is similar to that of
seawater. In high-energy environments tests are commonly heavy and robust and,
since they are made of material much denser than the seawater they displace,
they counteract any buoyancy of the soft parts. Also, in many environments
individuals gather detrital particles in their reticulopodia while feeding, as
camouflage and possibly as additional counter buoyancy aids.
5.
To offer protection from predators. There is no direct evidence of this. Some species are
more conspicuous because of their form or colour and are therefore
preferentially selected by predators.
6.
To assist growth of the cell. Foraminiferal cells are relatively large and some exceed 3 cm . The test
serves as a container that not only houses the cell but also provides
additional space that may be used for growth or for storage, e.g., of
stercomata (Mullineaux, 1987). In active individuals the test is incompletely
filled with cytoplasm but when the reticulopodia are withdrawn into the test it
may become filled. In the large form, Alveolinella quoyi, on average only 43%
of the test is filled (Severin and Lipps, 1989) and deep-sea forms have highly
vacuolated cytoplasm filling only part of the test. In shallow-water environments
rich in food, the test is normally filled with dense cytoplasm.
The six possible functions of the test are not mutually exclusive. It is
clear that some of the features of the test described by taxonomists as
‘ornament’ are definitely functional. Tubercles and structures such as teeth in
the aperture serve to break up aggregates of food and detritus, ribs channel
the extrathalamous cytoplasm (Banner and Culver, 1978; Kitazato, 1990; Bernhard
and Bowser, 1999) and spines support pseudopodia and help stabilise the test on
soft substrates. Some rotaliids have a canal system that replaces primary and secondary
apertures and allows communication between the chambers and the test surface
for the extrusion of extrathalamous cytoplasm and reticulopodia, for removing
waste products and for release of juveniles during reproduction (Ro¨ ttger et
al., 1984).
7/15/16
MARSH FORAMINIFERA
There is no fundamental difference in the low-diversity foraminiferal assemblages of marshes and mangals. The characteristic feature is the abundance of agglutinated taxa (Figure 4.1). In pre-1978 references by various authors, the forms now distinguished as Jadammina macrescens and Balticammina pseudomacrescens were not separated and were commonly grouped under Jadammina or Trochammina macrescens. Species may be infaunal or epifaunal, the latter mainly free living but sometimes clinging to algal filaments. They are a mixture of detritivores and herbivores. Siphotrochammina lobata and Trochammina inflata are epiphytic on algae in Brazilian mangrove swamps (Eichler et al., 1995). Trochammina inflata forms a rigid cyst of detrital material in which asexual reproduction takes place. Within the cyst it concentrates fine detrital particles that will be used to form the wall of the juveniles. Within 24 hours of forming a cyst, the juveniles are dispersed (Angell, 1990). Living Jadammina macrescens and Balticammina pseudomacrescens occur with random orientation on filamentous algae whereas Tiphotrocha comprimata is more firmly attached by its umbilical side. Jadammina macrescens is most abundant on the decaying leaves of Carex (Alve and Murray, 1999). Miliammina fusca sometimes occur aperture downwards on dead leaves. This author has never observed foraminifera on the stems of the living halophytes. With the exception of Miliammina fusca, the agglutinated species listed above are confined to marsh/mangal. However, although calcareous species from adjacent tidal flats and subtidal areas may extend onto low to mid marshes and sometimes occur in high abundance, none is confined to marsh/mangal: Ammonia group, Elphidium spp. and Haynesina germanica (Figure 4.2). Marsh foraminifera have been recorded living in areas not connected to the sea. For instance, in northern Germany there are inland marshes where saltrich waters come to the surface from underlying evaporite deposits and these have a fauna solely of Jadammina macrescens (as Jadammina polystoma, Haake, 1982). In Canada Polysaccammina ipohalina and Balticammina pseudomacrescens (as Jadammina macrescens) have been recorded living in salt springs (Patterson et al., 1990) and a new species has been recorded from Lake Winnipegosis
Figure 4.1. Scanning electron micrographs of marsh agglutinated foraminifera (longest dimension, mm). 1. Ammoastuta salsa (400). 2. Ammotium salsum (620, 200). 3. Arenoparrella mexicana (315, 350, 220). 4. Haplophragmoides wilberti (395, 300). 5. Balticammina pseudomacrescens (370, 340, 500). 6. Jadammina macrescens (250, 260, 400). 7. Paratrochammina guaratibaensis (400, 210, 230). 8. Siphotrochammina lobata (385, 290, 275). 9. Trochammina inflata (460, 430, 460). 10. Miliammina fusca (350, 220, 425).
Figure 4.2. Scanning electron micrographs of lagoon foraminifera (longest dimension, mm). 1. Elphidium albiumbilicatum (120, 150). 2. Elphidium clavatum (400, 420). 3. Elphidium delicatulum (285, 285). 4. Elphidium excavatum (300, 310). 5. Elphidium galvestonense (325, 325). 6. Elphidium granosum (420, 275). 7. Elphidium gunteri (200, 450). 8. Elphidium lidoense (390, 440). 9. Elphidium poeyanum (290, 350). 10. Elphidium subarcticum (440, 510). 11. Elphidium williamsoni (330, 410). 12. Elphidiella hannai (240). 13. Haynesina germanica (420, 470). 14. Haynesina nivea (180, 200). 15. Haynesina orbiculare (450, 450).
(Patterson and McKillop, 1991). It is considered likely that the foraminifera were transported inland on the feet of migrating sea birds.
Refrensi :Ecology and Aplications of Benthik Foraminifera, John Murray, 2006, Cambridge University Press.
7/10/16
BOOK:-- Sand Mining: environmental impacts and selected case studies.
EDITORS:-- [D. Padmalal, K. Maya, 2014]
| English | PDF | 11 MB | 162 pages | 2014 |
CONTENTS:---
Ch.1. Introduction
Ch.2. Rivers-Structure and Functions
Ch.3. River Sand Mining and Mining Methods
Ch.4. Impacts of River Sand Mining
Ch.5. Sand Mining: The World Scenario
Ch.6. Environmental Case Studies from SW India
Ch.7. EIA of River Sand Mining
Ch.8. Mining Strategies and Management
Ch.9. River Sand Auditing: An Example from SW India
Ch.10. Sand: The Fine Aggregate
Ch.11. Sources of Sand and Conservation
OVERVIEW:---
This book addresses most of the environmental impacts of sand mining from small rivers The problems and solutions addressed in this book are applicable to all rivers that drain through densely populated tropical coasts undergoing rapid economic growth.
http://www.mediafire.com/
BOOK:--Time Matters: Geology's Legacy to Scientific Thought
EDITORS:-- [Michael Leddra, 2010]
| English | PDF | 6 MB | 288 pages | 2010 |
CONTENTS:---
Ch.1. Introduction
Ch.2. Geological time
Ch.3. Dating rocks
Ch.4. The origins of the geological time scale
Ch.5. Plutonism versus Neptunism
Ch.6. Uniformitarianism versus Catastrophism
Ch.7. Evolution
Ch.8. Evolution versus Creationism
Ch.9. Continental Drift and Plate Tectonics
Ch.10. What have we learnt?
OVERVIEW:---
Time Matters provides an invaluable insight into the background behind some of the key concepts we use in Earth science today. It shows the historical context in which these ideas were developed, the important contributions of individual scientists and thinkers, and how these ideas continue to shape our view of science and the world in which we live.
The book covers subjects such as the age of the earth, catastrophism vs uniformitarianism, evolution vs creationism, plutonism vs neptunism, continental drift and plate tectonics.
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