Preface Mangrove Ecology – Applications In Forestry And .
Available online at www.sciencedirect.comAquatic Botany 89 (2008) 77www.elsevier.com/locate/aquabotPrefaceMangrove ecology – applications in forestry andcostal zone management‘‘In Persia in the Carmanian district, where the tide is felt,there are trees [Rhizophora mucronata] . . . [that] are alleaten away up to the middle by the sea and are held up bytheir roots, so that they look like a cuttle-fish’’Theophrastus (370–285 B.C.E.), Enquiry into Plants IV. VII. 5(Translated by Sir Arthur Holt, 1916)Mangrove forests have entranced and intrigued naturalists,botanists, zoologists, and ecologists for millennia. Over twothousand years ago, Theophrastus published perhaps the firstexplanation of why the roots of these trees grow abovegroundand how they grow in brackish and salty water, and he alsoobserved that their viviparous seeds sprouted while they are stillwithin the fruits attached to the branches. Straddling the landand sea, mangroves provide natural resources of both; wood forlumber and fuel, and fish and prawns for protein. They are hometo resident and migratory birds, snakes, and mammals, andsimultaneously support incredible diversity and biomass ofcrabs, sponges, tunicates, and other benthic marine invertebrates. Mangroves absorb nutrients and sediments flowingdown rivers from uplands through estuaries, and they offerprotection to these uplands and estuaries from battering wavesand cyclonic storms. In this new millennium, we must ask if thediversity of mangroves and the many ecosystem functions theyprovide can be retained and sustained when mangrove forestscontinue to be cut to provide logs for charcoal kilns and woodchips for rayon mills, drained to construct commercialaquaculture operations, filled with garbage, and ‘‘reclaimed’’for coastal developments.The twelve papers in this special issue of Aquatic Botanyon the ecology of mangrove forests provide comprehensivereviews of the fundamental knowledge that literally thousandsof scientists have accumulated over hundreds of years thatcan be used to answer these pressing questions. The papersrange widely and represent many scientific disciplines:0304-3770/ – see front matter # 2008 Elsevier B.V. All rights logy, population biology, ecosystem ecology, economics, and sociology, to name just a few. By providingsummaries and syntheses of existing data, the 54 authors andco-authors of these papers set the benchmarks and foundations on which future studies will build. Perhaps moreimportantly, these reviews illustrate clearly that for addressingmany issues that are central to the conservation, management,and preservation of mangrove ecosystems, there is more thanenough data to make informed decisions and to guide sensibleactions.Between one and two percent of the world’s mangroveforests are being lost to chainsaws, prawn and crab ponds, andnew settlements, condominiums, and waterfront resorts eachyear. This rate of destruction is comparable to the annual rate atwhich upland tropical forests are being cut, burned, andconverted to pastures, farms, towns, and cities. Declarationsfrom regular conferences organized by academics, individualgovernments, regional interest groups, non-governmentalorganizations, and the United Nations routinely decry the lossof mangroves, but often encourage more research before theneeded actions can be reliably implemented. Although thedozen papers in this issue identify gaps in our knowledge, thesepapers clearly show that those gaps are small relative to the vastamounts of information available to policy analysts, decisionmakers, and managers. The data are here, well organized andclearly presented. Use these data wisely: the time for actionis now.Aaron M. Ellison*Harvard University, Harvard Forest,324 North Main Street, Petersham, MA 01366, USA*Fax: 1 978 724 3595E-mail address: aellison@fas.harvard.eduAvailable online 15 January 2008
Aquatic Botany 89 (2008) 78–79Contents lists available at ScienceDirectAquatic Botanyjournal homepage: www.elsevier.com/locate/aquabotPersonal reportAquatic Botany special issue dedication to Samuel Curry Snedaker(22 May 1938–21 March 2005)This special issue of Aquatic Botany is inspired on the well-knownUNESCO publication by Snedaker and Snedaker (1984). More than adecade has passed since another major issue on the biodiversity andfunction of mangrove ecosystems has been published (Field andWhittaker, 1998). The contacts for publishing the present specialissue were established on a series of Australian mangrove andwetland conferences and workshops in 2006. Our aim was to providea series of comprehensive reviews on mangrove ecology, inparticular on applications in forestry and coastal zone management.We highlight the existence of a parallel special issue focusing moreon macrobenthic fauna from mangroves (Lee and Dittmann, 2008).Finally, we refer to Aaron Ellison’s preface to this Aquatic BotanySpecial Issue on ‘Mangrove ecology—applications in forestry andcoastal zone management’ for a state-of-the-art of mangroveecosystems (Ellison, 2008), before coming back to the inspirationby and dedication to a great man.In this dedication we want to express our respect to the lateSam Snedaker with a few anecdotes:Al Ain, United Arab Emirates, December 1996. I still cannotbelieve Nico sent me to my first international conference abroad as astarting PhD student. Have you seen the program? Snedaker, Duke,Saenger, Lee, Field, Ball, Popp,. . . what on Earth am I going to present tothése people? Thé Snedaker is going to be there! But then came theannouncement of my presentation . . .Immediately after that I was confronted with Sam’s charisma.He calmly came towards me and made me feel as if I were one ofthe big names on that program. He gave me so much confidenceduring the talks we had that I was convinced there was a mangrovefuture out there.Miami, Florida, September 1999. Coming back from the NewOrleans conference of the Estuarine Research Foundation therewas only one stop to make for us before crossing the Atlantic again,and that was Sam’s office in Miami and the New World mangrovesnearby. The most remarkable sight that is burnt in our minds isAvicennia germinans cut like a hedge on the nearby golf course, andthe most remarkable remembrance of Sam was his hospitalitywhen he invited us into his small office.With the courtesy of Rafael J. Araujo we use some of thebeautiful words with which he described Sam, which is exactlyhow we remember him and how we feel about him.‘‘I always wanted to know how Sam felt about this legacy. Washe proud of it? Did it open doors for him? – He would look at meand say nothing. You see, there was a detachment about Sam, amystery about him that unsettled many. Sam was especiallygood at concentrating large thoughts into a little space, at0304-3770/ – see front matterdoi:10.1016/j.aquabot.2008.02.008getting to the heart of things, and at preserving valuableinformation. His words were few, but carried weight. I lovedhim for all he knew, taught me and said; but also for his silence.I miss his quiet entry into the office, his unobtrusiveness, hissense of privacy and calm. . .’’Sam, this mangrove issue of Aquatic Botany is in your memory. Amemory that we will keep alive, and a memory that makes usrealise to whom this poem of mine was destined:
Personal report / Aquatic Botany 89 (2008) 78–79ReferencesAraujo, R.J., 2005. Samuel Curry Snedaker (1938–2005). Bull. Mar. Sci. 76, 623–624.Ellison, A.M., 2008. Preface. Preface. Aquat. Bot. 89, 77.Field, C.B., Whittaker, R.J., 1998. Biodiversity and function of mangrove ecosystems.Glob. Ecol. Biogeog. Let. 7, 1–94.Lee, S.Y., Dittmann, S., 2008. Preface. J. Sea Res. 59, 1–11.Snedaker, S.C., Snedaker, J.G., 1984. The Mangrove Ecosystem: Research Methods.UNESCO, Paris.Farid Dahdouh-Guebas*Biocomplexity Research Focus(Complexité et Dynamique des Systèmes Tropicaux),Département de Biologie des Organismes,Université Libre de Bruxelles – ULB,Campus du Solbosch, CP 169,Avenue Franklin D. Roosevelt 50,B-1050 Bruxelles, Belgium79Biocomplexity Research Focusc/o Laboratory of Plant Science and Nature Management,Mangrove Management Group,Vrije Universiteit Brussel – VUB,Pleinlaan 2, B-1050 Brussels, BelgiumNico KoedamBiocomplexity Research Focusc/o Laboratory of Plant Science and Nature Management,Mangrove Management Group,Vrije Universiteit Brussel – VUB,Pleinlaan 2, B-1050 Brussels, Belgium*Corresponding author.Tel.: 32 2 629 34 22/650 21 37; fax: 32 2 629 34 13E-mail address: fdahdouh@ulb.ac.be (F. Dahdouh-Guebas)Available online 10 March 2008
Aquatic Botany 89 (2008) 80–92Contents lists available at ScienceDirectAquatic Botanyjournal homepage: www.elsevier.com/locate/aquabotReviewLong-term retrospection on mangrove development using transdisciplinaryapproaches: A reviewF. Dahdouh-Guebas a,b,*, Nico Koedam baBiocomplexity Research Focus (Complexité et Dynamique des Systèmes Tropicaux), Département de Biologie des Organismes, Université Libre de Bruxelles – ULB,Campus du Solbosch, CP 169, Avenue Franklin D. Roosevelt 50, B-1050 Bruxelles, BelgiumbBiocomplexity Research Focus c/o Laboratory of Plant Biology and Nature Management, Mangrove Management Group, Vrije Universiteit Brussel – VUB,Pleinlaan 2, B-1050 Brussels, BelgiumA R T I C L E I N F OA B S T R A C TArticle history:Received 25 May 2007Received in revised form 6 March 2008Accepted 13 March 2008Available online 29 March 2008Large ecosystem processes often take place beyond the observation time of a researcher. Yet, throughretrospective research scientists can approach and understand ecosystem changes. This contributes tothe fundamental understanding of both human-induced and natural dynamics in ecosystems worldwide. This also holds for fast changing coastal areas with mangrove ecosystems, which are important forbiodiversity, for coastal protection, and for the daily livelihood of millions of people in tropical coastaldeveloping countries. In addition, retrospective research generates a basis for predictions that can beused early on to protect an ecosystem. In attempting to protect ecosystems from adverse human-inducedchange and destruction, and to manage them for sustainability, scientists are only beginning toinvestigate and understand natural ecosystem dynamics. It is important and advisable to gather, combineand analyse all possible data that allow a researcher to look back in time. This paper reviews the availableretrospective methods, and highlights the transdisciplinary way (i.e. combination between basic andapplied sciences on one hand, and social and human sciences on the other) in which retrospectiveresearch on a scale between months and centuries can be carried out, but it also includes methods onlarger scales that may be marginally relevant. The paper particularly emphasizes the lack oftransdisciplinary (not interdisciplinary) integration between sciences in retrospective research onmangrove forests in the past.ß 2008 Elsevier B.V. All rights onologyEcosystem reconstructionEthnoscienceFieldworkHistorical eLandscape ionRadiocarbonReligionRemote .Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Retrospective data from the basic and applied sciences2.1.Above-ground fieldwork observations. . . . . . . . .2.2.Lichenometry . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.3.Dendrochronology . . . . . . . . . . . . . . . . . . . . . . . .8181818282* Corresponding author at: Biocomplexity Research Focus c/o Département de Biologie des Organismes, Université Libre de Bruxelles - ULB, CP 169, Av. F.D. Roosevelt,B-1050 Bruxelles, Belgium. Tel.: 32 2 650 21 37/629 34 22; fax: 32 2 650 21 25/629 34 13.E-mail address: fdahdouh@ulb.ac.be (F. Dahdouh-Guebas).0304-3770/ – see front matter ß 2008 Elsevier B.V. All rights reserved.doi:10.1016/j.aquabot.2008.03.012
F. Dahdouh-Guebas, N. Koedam / Aquatic Botany 89 (2008) 80–923.4.812.4.Landscape (repeat) photography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.5.Air- and space-borne remote sensing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.6.Isotope analyses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.7.Substrate cores . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.8.Geomorphological and paleontological data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.9.Hereditary and evolutionary feature differentiation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Retrospective data from the social and human sciences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.1.Interviews . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.2.Historic archives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.3.Spiritual heritage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.4.Archaeological and paleoethnobiological data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Transdisciplinary retrospective approaches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Acknowledgements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .82838383848484848485868688References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .891. IntroductionMangrove forests occur along tropical and subtropical coastlinesand serve as breeding, spawning, hatching, and nursery grounds formany marine species (Baran, 1999; Barbier, 2000; Nagelkerken et al.,2008; Cannicci et al., 2008). Next to this habitat function, mangrovesalso provide wood and non-wood forest products and values toindigenous people (Bandaranayake, 1998; Ewel et al., 1998; Gilbertand Janssen, 1998; Rönnbäck, 1999; Bandaranayake, 2002; Mobergand Rönnbäck, 2003; Walters et al., 2008). They may act as a physicalbarrier to protect human settlements from the ocean (Badola andHussain, 2005; Dahdouh-Guebas et al., 2005c; Danielsen et al., 2005;Dahdouh-Guebas and Koedam, 2006). It has been estimated thatapproximately 75% of tropical coasts world-wide were once fringedwith mangroves (Chapman, 1976), but at present a world withoutmangroves is no longer an unrealistic prospect (Duke et al., 2007).Despite their values, mangroves are amongst the most threatenedecosystems world-wide, subject to over-exploitation, pollution, andconversion (Farnsworth and Ellison, 1997). In particular the largescale conversion of mangrove forests to ponds for shrimpaquaculture is an underestimated problem (Naylor et al., 2000a,b;Dahdouh-Guebas et al., 2002b; Primavera, 2005). Not only direct ordestructive anthropogenic effects such as clear felling, but alsoindirect impacts such as changes in hydrography have proveddetrimental to mangroves (Dahdouh-Guebas et al., 2005b,c). Inaddition, climate change poses a threat to mangrove ecosystems(Gilman et al., 2008). This has stimulated many countries to payattention to natural or induced mangrove recovery (Stevenson et al.,1999; Lewis et al., 2005; Bosire et al., 2008). In many locations, theabove-mentioned threats have reduced the potential for economicrecovery. For instance, economic recovery from the 26/12/2004tsunami disaster is hampered because of the loss of traditionalincome sources related to coastal ecosystems rich in species and inecological functions (Adger et al., 2005; Hughes et al., 2005). Toreverse the eroding social-ecological resilience in mangrove areasunder threat, it is important to reconstruct the past of the mangroveecosystem, or better: the mangrove anthroposystem. This reconstruction is also the basis to understand its natural and anthropogenic dynamics (Berger et al., 2008), to forecast changes, andstrive for early mitigation.Few have attempted to forecast general impacts (Semeniuk,1994; Clarke, 1995; Ellison and Farnsworth, 1996; Woodroffe,1999), and even fewer to predict cryptic changes in more specificecosystem characteristics such as vegetation structure andcomposition (Dahdouh-Guebas and Koedam, 2002; DahdouhGuebas et al., 2002a, 2005a). These studies have pointed out thatthere is a lack of description and understanding of past changes,and present functions and processes, let alone the ability to predictfuture scenarios in mangrove ecosystems. The need for long-termenvironmental monitoring, research and paleoecological reconstructions of past environments has been stressed (Parr et al.,2003). Historical ecology data have been adopted in the past in thisperspective. Swetnam et al. (1999) state that ‘historical ecologyencompasses all of the data, techniques, and perspectives derivedfrom paleoecology, land use history from archival and documentary research, and long-term ecological research from monitoringand experiments extending over decades. Also included are timeseries from instrument-based observations of the environment,such as weather records, stream gauges, and data from satellites’.However, the ‘natural’ and ‘documentary archives’ that contributeto historical ecology are with few exceptions from within naturalsciences (Swetnam et al., 1999) overlooking highly valuableinformation derived from the social and human sciences (Cormier-Salem, 1999; Rist and Dahdouh-Guebas, 2006). This iscorroborated by the significant lack of integration betweendisciplines from various science domains, particularly in historicalresearch applied to mangrove forests. The term ‘retrospectiveresearch’ is used here to indicate all research approaches that lookback in time to understand the present (historical ecology,historical biogeography, etc. . .).The objective of this review paper is to highlight the potential ofretrospective research on mangroves, and to recommend transdisciplinary approaches based on a subset of retrospective researchmethods to improve our understanding of past changes and spatiotemporal dynamics on a scale between months and centuries. Inthis light, transdisciplinarity equals interdisciplinarity that transcends the science fields (basic and applied science; social andhuman science; life science) in particular, and science in general(incorporating indigenous forms of knowledge) (Rist and Dahdouh-Guebas, 2006).2. Retrospective data from the basic and applied sciences2.1. Above-ground fieldwork observationsMeasurements or visual observations in the field can beindicative for events in the recent past, such as tracks or brokenbranches for animal foraging, or concentrations of aromatichydrocarbons for pollution (Burns et al., 1993; MacFarlane et al.,2003). Ecosystem morphology and physiognomy can provide arange of information on the past. The position and physiognomy ofmangrove forests and coral reefs reflect changes on different timescales. Transient surface water levels (reflected in flood line markson the vegetation) and shoreline position respond most rapidly tocoastal environmental changes, and can be reflected in changes incolour, structure and mud coatings of stems and branches ofplants, notches in channel banks, aggregated surfaces of wetlands,and more geomorphologic indicators (Morton, 2002). Distribu-
82F. Dahdouh-Guebas, N. Koedam / Aquatic Botany 89 (2008) 80–92tional changes such as the natural expansion or regression ofmangrove vegetation (including possible changes in speciescomposition) and coral reefs are indicators of environmentalchanges occurring on the order of decades to millennia (Morton,2002; Dahdouh-Guebas et al., 2004). Past exploitation practicescan be deduced from the age structure and spatial distribution oftrees (Dahdouh-Guebas et al., 2002a), the straightness of trees(Kairo et al., 2002), or the presence of tree stumps or dead trees(Dahdouh-Guebas et al., 2004). The difficulty with most of theabove observations is that the time scale of reconstruction is veryvariable, and cannot always be quantified based on the observationalone (what is the time interval for a change to occur or to beobservable?).2.2. LichenometryBased on the radial, slow and steady growth of most lichens,lichenometry is commonly used as a technique to date theexposure of certain natural or human features, such as bridges,gravestones, landslides or geological features (Bull and Brandon,1998; Winchester and Chaujar, 2002). However, the assessment oflichens in forest gap dynamics (Benson and Coxson, 2002) alsoopens doors to lichenometry in a mangrove forest ecosystemcontext. Lichens do occur in mangroves (e.g. Ellison, 1997), but arenot well studied, let alone used in lichenometry.ago a tree died. To solve this, methods have been proposed toestimate the time a dead tree has been on the ground (Gore et al.,1985; Johnson and Greene, 1991).2.4. Landscape (repeat) photographyLandscape photography from a single location is often used toview the typical landscape features under different environmentalconditions such as seasons in temperate regions, or inundation influvial or tidal forests (Stafford-Deitsch, 1996). Such comparativephotographs have also been used to compare the ‘before’ and ‘after’situations in case of catastrophes or successive stages inrestoration studies (Lewis, 1982; Finn, 1996; Turner and Lewis,1997; Stevenson et al., 1999). However, apart from documentarybooks for a wide audience (Vanhecke et al., 1981), few scientistsused sequential photographs to actually research ecosystem orvegetation changes (e.g. Rogers et al., 1984; Butler and DeChano,2001; Brook and Bowman, 2006; Moseley, 2006), or to corroborateother data (e.g. Wolanski and Gereta, 2001). Although the analysisof such sequential photographs is often limited to visualinspection, the inherent information to interpret ecosystemchanges in a wide framework can be very valuable (Fig. 1).Landscape photography or repeat photography definitely qualifiesas a cheap and accessible data source for the present and future,but for the past it evidently requires reference photographs.2.3. DendrochronologyDendrochronology is the science of measuring time-relatedfeatures in the wood of woody plants. As woody plants grow, treecambium produces xylem at the pith side of a root, stem or branchsection, which may display variable characteristics depending onseasons or environmental conditions. Seasonal climates of thetemperate type induce the formation of rings in the xylem of a tree.Dendrochronologic research can be purely based on the woodanatomical characteristics of these tree rings that must be analysedvisually or through image analysis (Cherubini et al., 2003), or it canbe based on the analysis of isotopes extracted from the successivetree rings (February, 2000). However, both approaches areobscured in areas where the spatio-temporal climatic variabilityinhibits tree rings to form consistently such as under mediterranean or tropical climates (Cherubini et al., 2003). Nevertheless, forthe mangrove trees rings have demonstrated to be useful for agedetermination (Menezes et al., 2003; Verheyden et al., 2004a), withpotential for dendrochemistry (Verheyden et al., 2004b, 2005a)and for research on wood anatomy and hydraulic architecture(Schmitz et al., 2006). Growth layers of Avicennia are not annualwhich is, however, related to their peculiar growth via successivecambia (Schmitz et al., 2007a,b). Some other mangrove species doshow growth rings in regions with a seasonal climate. InRhizophora mucronata Lamk., annual growth rings were identifiedin Kenya (Verheyden et al., 2004a,b) and also Heritiera fomes Buch.Ham and Sonneratia apetala Buch.-Ham from Bangladesh show agood potential for dendrochronological research (Chowdhuryet al., in press).Following the above approach, environmental and ecologicalaspects of a system can be deduced from the characteristics of thetree rings. Dendroecology may reveal changes in for instance fireincidence (Stephens et al., 2003), climatic conditions (Briffa et al.,1998; Verheyden et al., 2005b), total environments or ecosystems(February, 2000), sea-level rise (Yu et al., 2004) and evenretrospective information on fish abundance hidden in the ringsof riparian trees (Drake et al., 2002). Normally the natural archivingof information, which can be used in dendrochronology, stopswhen a tree dies, and it is therefore important to know how longFig. 1. Repeat landscape photography of a selected mangrove stand in Gazi Bay(Kenya) from approximately the same place taken in 1993 (top) and in 2003(bottom). Over a period of 10 years, the unaffected Sonneratia alba J. Smith stand onthe background is thriving, but the cleared mangrove area on the foreground hasfailed to recover naturally from the over-exploitation, necessitating rehabilitation(cf. Bosire et al., 2008).
F. Dahdouh-Guebas, N. Koedam / Aquatic Botany 89 (2008) 80–922.5. Air- and space-borne remote sensingOne of the most widely used methods to look into the recentpast, and which will undoubtedly evolve into the single mostimportant monitoring technology in the future, is remote sensing.There is a large difference between air- and space-borne remotesensing as far as their spatial, temporal and spectral characteristicsare concerned (Green et al., 2000; Dahdouh-Guebas, 2002).Whereas satellite remote sensing is a relatively new technologythat started with the Apollo program in 1963, the first black/whiteaerial photographs were taken in 1858 from a hot air balloon, andin 1906 from an airplane. It was during World War I that aerialphotography missions on a large scale were launched. Hence, aerialphotography constitutes the only available imagery for retrospective monitoring on a sequential scale of decades, starting longbefore the birth of space technology (Dahdouh-Guebas et al.,2000b). Aerial photography remains the only imagery with thehighest spatial resolution, and is often preferred to satelliteimagery (Ramsey and Laine, 1997; Mumby et al., 1999; Hyyppäet al., 2000; Manson et al., 2001; Thampanya et al., 2006). Ofcourse, the choice of a particular sensor depends on the studypurpose (cf. Blasco et al., 1998).From as recently as 2001, images of very high spatial resolutionand of good spectral resolution from space-borne sensors (Ikonos,Quickbird, OrbView) have made it possible to optimise theidentification of differential assemblages, genera and specieswithin and beyond mangrove ecosystems (Wang et al., 2004;Dahdouh-Guebas et al., 2005a; Kovacs et al., 2005). Before that, theapplication of satellite sensors in change detection was limited tolarge homogeneous land-cover or land-use classes. The researchcommunity should consider also the ‘physiognomic resolution’ ofremote sensing methods or of any method. The ‘physiognomicresolution’ is referred to as the form that a method is able toidentify within the variety of life forms, or as the ecological entitythat a method is able to identify within an ecosystem (e.g. forest,individual). It implies that the identified level can be monitored todetect temporal changes in it. For instance, a method (e.g. a sensor)that is able to make physiognomic distinctions such as ‘grassland’,‘forest’, ‘submerged vegetation’, even if fitted with furthercharacterisations like ‘dense’ and ‘sparse’, would be consideredhaving a ‘low physiognomic resolution’. So would a method thatcan only detect whether an ecosystem entity is mangrove forest ornot, without further details. However, a method that succeeds inidentifying the taxonomic level of species or even individualswould be considered having a very high physiognomic resolution.Studies that serve to pinpoint individual trees will require methodswith a very high physiognomic resolution.Next to spatial resolution of remote sensing sensors andphysiognomic resolution, the very high temporal resolution ofsatellite remote sensing (as frequent as 3 days to revisit a particularplace) is conducive for the detection of changes on small temporalintervals. The higher radiometric resolution is also an advantage.Unfortunately, the highly commercialised cost poses a restrictionon its use by institutions in developing countries.2.6. Isotope analysesIsotope analysis may e
on macrobenthic fauna from mangroves (Lee and Dittmann, 2008). Finally, we refer to Aaron Ellison’s preface to this Aquatic Botany Special Issue on ‘Mangrove ecology—applications in forestry and coastal zone management’ for a state-of-the-art of mangrove ecosyste
karya tulis dalam bentuk laporan apapun tanpa izin Unismuh Makassar. ABSTRAK . Tumbuhan mangrove merupakan ekosistem hutan tropis yang letaknya berbatasan antara darat dan laut (Zhou et.al, 2006). Mangrove merupakan . ekologi, maupun sumber daya ilmiah dan budaya. Tumbuhan mangrove
design and establishment of a marine plant (specifically mangrove) nursery; outline specific growth characteristics of selected mangrove species; provide details of the impacts of pruning trials on nursery stock; and describe trial restoration methods for tidal fish habitats by selective use of nursery-reared mangrove stock.
population ecology) and then subsequently covering interactions between species in a community (i.e., community ecology). However, to facilitate completion of the final paper, I have recently switched to covering community ecology and ecosystem ecology before population ecology. As both ecology and evolution have to be covered in the same .
perikanan payau dengan kolam jebak ataupun keramba jaring apung. Saat ini pemanfaatan tumbuh-tumbuhan di ekosistem mangrove sebagai bahan pangan dan untuk pengobatan semakin meningkat. Buah dari tumbuhan mangrove dapat diolah menjadi bahan pangan pengganti makanan pokok yang mengandung karbohidrat. Dengan demikian, selain beras,
Penelitian Struktur Komunitas Mangrove di Pulau Keter Tengah Kabupaten Bintan Provinsi Kepulauan Riau bertujuan untuk mengetahui struktur komunitas mangrove dan kondisi lingkungannya saat ini (eksisting). Penelitian ini telah dilakukan pada bulan Februari sampai Mei 2013 dengan metode transek kuadran. Jalur transek terpanjang
pada 6 plot. Struktur Komunitas Analisis struktur komunitas pada area Gisik Pantai Pasirmendit, yang kami amati adalah mangrove sejati. Berdasarkan pengamatan, terdapat empat jenis mangrove sejati yang tumbuh di area Gisik Pantai Pasirmendit yaitu,Avicennia marina, Avecennia ovisinalis, Rhizophora appiculata, dan Sonneratia caseolaris.
Mangroves and mangrove ecosystems have been studied extensively but remain poorly understood. With continuing degradation and destruction of mangroves, there is a critical need to understand them better. Aspects of mangrove biology have been treated in several recent reviews. Tomlinson (1986) described the
“Am I My Brother’s Keeper?” Cain & Abel by Tintoretto. Everything can be taken from a man but the last of the human freedoms - to choose one’s attitude in an given set of circumstances, to choose one’s own way.--Auschwitz Survivor, Victor E. Frankl Human Gene Map. OnegShabbat Archives –Emanuel Ringleblum Remembrance: To record and to teach future Generations. The time has come to .
