Tesi sul tema "Mangrove swamps"

Patterns of distribution of crabs inhabiting burrows in three temperate mangrove swamps near Sydney, New South Wales, were described. Heloeoius cordiformis (an ocypodid) did not exhibit a consistent pattern of distribution among three tidal zones, but was always associated with well— drained mounds of substratum within zones. Paragrapsus laevis (a grapsid) tended to be most abundant in the lower two zones on the shore and usually inhabited burrows in the moist or submerged flats between mounds. Sesarma erythrodactyla (a grapsid) was distributed fairly evenly among the three tidal zones and also between mounds and flats. H. cordiformis hibernated in burrows from June through August or September. Overall abundances also varied seasonally, but trends were inconsistent among the three swamps sampled.

The earth is undergoing its sixth mass extinction event. This biodiversity crisis is directly attributable to anthropogenic disruptions of ecosystem processes. These disruptions include extracting and killing organisms, clearing habitat, introducing exotic species and disrupting climate at a global-scale. Connectivity is an attribute of both populations and ecosystems which, when disrupted, leads to fragmentation. Fragmented systems often have lower ecological functioning and resilience than connected systems. The maintenance of natural rates of ecological connectivity is a major challenge. Mangroves are intertidal forests which grow along the subtropical and tropical coasts of the world. These forests are extremely valuable; maintaining coastal water quality, protecting shorelines from severe weather events, providing habitat for fisheries species and iconic megafauna, and sequestering blue carbon. Unfortunately, mangrove forests also remain vulnerable to the many human activities competing for space in the coastal zone, and to the effects of sea-level rise (SLR). One of the keys to ensuring mangrove conservation and functioning into the future is a thorough understanding of the connectivity and fragmentation of these systems. This thesis consists of four studies. The first is a comprehensive review of research on marine population connectivity. This study identified that intertidal wetlands are particularly under-represented in the marine connectivity literature. This chapter led to the remaining three chapters which assess fragmentation and connectivity in mangroves. The first of these is a mark-recapture experiment which considers connectivity at the population level. I modelled intra-forest dispersal of mangrove propagules as the interaction between propagule and habitat attributes. I identified interactions and thresholds that determine the capacity for propagules to disperse efficiently. The other two chapters consider mangrove fragmentation at a landscape level. The first of these is an assessment of mangrove fragmentation at a global-scale. I identified regions where loss and fragmentation occur as well as how the dominant land-use change in a region mediates the relationship between loss and fragmentation. In the final chapter, I projected the gain, loss and changing connectivity of mangrove and saltmarsh habitats in southeast Queensland, Australia, given a range of SLR and development scenarios. In this chapter I identify how geographic attributes of coastal regions mediate wetland resilience and vulnerability to climate change scenarios, and demonstrate the threat of SLR to both mangrove and saltmarsh habitats in southeast Queensland. This thesis uses a collection of related chapters to address fragmentation and connectivity in mangroves. My intention is to promote further research into the previously under-studied topic of ecological impacts of fragmentation in mangroves.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
Full Text

Mangrove habitats are considered as the ideal fish nursery as they are known to increase the growth and survival of juvenile fishes by providing enhanced food availability and protection. However, most studies have focused on tropical mangroves with a few recent warm temperate studies finding conflicting results. Furthermore, the nursery value of South African mangroves to fishes remain understudied in subtropical areas, while warm temperate mangroves are yet to be evaluated. This study aimed to assess whether mangrove presence leads to any advantage to the larvae of an important estuarine resident fish species, Gilchristella aestuaria, by comparing the food patch quality of South African warm temperate mangrove and non-mangrove estuaries. Results indicate that larvae fed primarily on the dominant prey species, Pseudodiaptomus hessei, Paracrtia longipatella, and Acartiella natalensis. However, postflexion larvae consumed more of the larger species, P. hessei, within the two mangrove estuaries (16.09 %V in Nahoon and 13.79 %V in Xhora) than the two nonmangrove estuaries (12.20 %V in Gonubie and 7.05 %V in Qora), despite other prey species occurring at similar densities. Results indicate that mangrove habitats acted as sediment sinks, slightly reducing the turbidity of these estuaries which resulted in postflexion larvae actively selecting larger, more nutritious prey, which in turn, significantly increased their individual instantaneous growth rates (0.11 ± 0.21 Gi) when compared to postflexion larvae in non-mangrove estuaries (0.09 ± 0.12 Gi). This study found that mangrove presence was significantly related to postflexion larval densities when coupled with abiotic (such as temperature and turbidity) and biotic factors (such as predator-prey interactions). Understanding the spatial and temporal dynamics, predator-prey interactions as well as the growth and survival of G. aestuaria is particularly important as they are key zooplanktivores that are prey to other species in estuarine food webs.

Estuarine habitats along the temperate south-eastern shores of Australia are generally made up of salt marsh, mangrove forests and seagrass beds. In urban areas these habitats have been progressively fragmented as a result of population increase and industrial expansion. Salt marshes in particular have been vulnerable to urban expansion and reclamation because of their close proximity to densely populated areas, while mangrove forests have been less often reclaimed because of frequent tidal inundation. The effect of reclamation of salt marshes on the biotic assemblages and functioning of mangrove forests with an adjacent salt marsh, park or bund wall was examined at nine separate locations on the Parramatta River, Sydney NSW. A mensurative approach was used to describe the patterns of distribution and abundance of macro fauna at several temporal and spatial scales. The implications for management are that salt marshes are an integral part of estuaries, and smaller patches of salt marsh are just as important as larger patches in maintaining the diversity of faunal assemblages and ecosystem functioning in mangrove forests in urban areas
Master of Science (Hons)

Orientadores: Valéria Maia Merzel, Anete Pereira de Souza
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: Os manguezais são ecossistemas peculiares de alta atividade biológica, considerados um dos ambientes mais ricos do mundo. No Brasil, os manguezais ainda são pouco estudados, tornando o conhecimento e exploração de micro-organismos e seus metabólitos nesses ecossistemas um tópico importante. Os manguezais são ambientes adversos, caracterizados, em muitos casos, pela alta salinidade, variações constantes de pH e temperatura, e condições anóxicas. Micro-organismos adaptados à essas condições podem ser fontes de moléculas bioativas ainda desconhecidas e de interesse ambiental e econômico. Neste contexto, o presente trabalho teve como um dos objetivos analisar a diversidade taxonômica e funcional presente em sedimento de manguezal contaminado com petróleo através do sequenciamento de uma biblioteca metagenômica construída em vetor do tipo fosmídio. As análises taxonômicas da biblioteca metagenômica mostraram predominância do filo Proteobacteria, seguido por Actinobacteria, Planctomycetes, Firmicutes, Cloroflexi e Bacteroidetes. Em nível de classe, a mais abundante foi Gamaproteobacteria, seguida de Alfaproteobacteria e Deltaproteobacteria. A diversidade taxonômica se reflete na diversidade metabólica, com espécies capazes de degradar hidrocarbonetos, oxidar enxofre em zonas de transição oxica-anóxica costeiras, transformar metais pesados e outros compostos xenobióticos, dentre outras habilidades. Em adição, foram realizadas triagens funcionais com 4.800 clones da biblioteca e 215 isolados bacterianos para esterase e lipase, 5.184 clones para atividade proteolítica e os genomas de duas bactérias foram analisados in silico na busca de genes que codificam para atividade de catalase. As triagens dos clones resultaram em 17 hits positivos para esterases que posteriormente se revelaram falsos-positivos, e 182 hits positivos para proteases nos ensaios com sondas, sendo 60 hits positivos no pH 4,0, 55 no pH 7,0 e 67 no pH 9,0. Nos ensaios com isolados de bactérias foram detectados 42 com atividade de esterase e 20 com atividade de lipase, sendo que a melhor atividade de esterase foi obtida com um isolado de Gordonia sp. e a melhor atividade de lipase foi obtida para um isolado de Bacillus safensis. Estes dois isolados já possuem seus genomas sequenciados e uma análise in silico foi realizada para busca dos respectivos genes de atividade lipolítica. Na busca in silico por catalases foi selecionada uma sequência completa para ensaios de expressão. Foram desenhados pares de primers para amplificação dos genes das três enzimas e, destes, os genes da lipase e da catalase foram expressos, ambos do Bacillus safensis. A caracterização funcional e estrutural foi realizada com a catalase, cujo gene possui 1500 pb, é um tetrâmero composto por 4 monômeros de 59 kDa cada, ativa em intervalo de pH de 6,0 a 12 e temperaturas de 25 ºC a 55 ºC, com atividade ótima em pH 10 e 30 ºC e estável até 40 ºC. Os resultados mostraram que o mangue impactado é composto por populações microbianas adaptadas ao ambiente, e também responsáveis pela degradação de compostos xenobióticos, auxiliando na sua recuperação. A abordagem metagenômica foi bem sucedida nas triagens funcionais para proteases, indicando um grande potencial proteolítico no ambiente. As triagens funcionais com os isolados mostraram a presença de enzimas lipolíticas ativas, e a catalase expressa exibiu características funcionais interessantes, tais como atividade ótima em pH 10 e estabilidade térmica até 40 ºC, com potencial aplicação industrial
Abstract: Mangroves are unique ecosystems of high biological activity and are considered one of the richest environments in the world. In Brazil, mangroves are still poorly studied, making the knowledge of microorganisms and their metabolites in these ecosystems an important topic. Mangroves are harsh environments characterized, in many cases, by high salinity, high pH and temperature variations, and anoxic conditions. Microorganisms adapted to these conditions may be sources of yet unknown bioactive molecules of environmental and economic interest. In this context, one of the objectives of the present study was to analyze the taxonomic and functional diversity present in mangrove sediment contaminated with oil through the sequencing of a metagenomic library constructed using fosmid vector. The taxonomic analysis of the metagenomic library showed predominance of Proteobacteria phylum, followed by Actinobacteria, Planctomycetes, Firmicutes, Chloroflexi and Bacteroidetes. At class level, the most abundant was Gammaproteobacteria, followed by Alphaproteobacteria and Deltaproteobacteria. The taxonomic diversity is reflected in the metabolic diversity, with species capable of degrading hydrocarbons, oxidizing sulfur in oxic-anoxic coastal transition zones, transforming heavy metals and other xenobiotic compounds, among other skills. In addition, functional screenings were performed with 4,800 fosmid clones and 215 bacterial isolates for esterases and lipases, and with 5,184 clones for proteolytic activity and the genomes of two bacteria were analyzed in silico to search for genes encoding catalase activity. The screening of the clones resulted in 17 positive hits for esterases that later proved to be false-positive, and 182 positive hits for proteases using probe-based assays: 60 positive hits at pH 4.0, 55 at pH 7.0 and 67 at pH 9.0. Tests with bacterial isolates yielded 42 positive hits for esterase activity and 20 for lipase activity. The best esterase activity was obtained with one isolate of Gordonia sp. and the best lipase activity was obtained with one isolate of Bacillus safensis. These two isolates have their genomes already sequenced and in silico analyses were performed in the search for the respective genes of lipolytic activity. In silico analysis for catalase genes was performed and a complete sequence was selected for expression assays. Primer pairs were designed to amplify the genes encoding the three enzymes, and of these, lipase and catalase were expressed, both from Bacillus safensis. The functional and structural characterization was carried out with catalase, which gene has 1500 bp, it is a tetramer composed of four monomers of 59 kDa each, active in the pH range from 6.0 to 12 and temperatures of 25 °C to 55 °C, with optimum activity at pH 10 and 30 °C and stable until 40 ºC. The results showed that oil-impacted mangrove is composed by microbial populations adapted to the environment, responsible for the degradation of xenobiotics and assisting in the recovery of the mangrove. The metagenomics approach was successful in the functional screening for proteases, indicating a great proteolytic potential in the environment. Functional screening with the bacterial isolates showed presence of active lipolytic enzymes, and the expressed catalase exhibited unique functional characteristics, such as optimal activity at pH 10 and thermal stability until 40 ºC, with potential industrial application
Doutorado
Genetica de Microorganismos
Doutora em Genética e Biologia Molecular

La présence d'obstacles rencontrés en milieu naturel par l'écoulement, influence la dispersion des polluants qu'il transporte. Cette thèse, fondée sur des mesures micro-météorologiques spatio-temporelles en région tropicale, vise à étudier la dispersion de composés émis par l'écosystème mangrove en fonction des conditions météorologiques. A l'échelle journalière, l'analyse météorologique révéle, outre la présence des Alizés, l'existence d'écoulements thermiques dont des paramètres thermodynamiques nocturnes ont été définis. L'observation terrain nous a montré que la faible intensité du vent défavorise la dispersion des composés émis durant la nuit. A une échelle plus fine, l'existence d'un trou spectral séparant les phénomènes de grande échelle de ceux liés à la turbulence a été mise en évidence. Ces derniers ont été traités par des approches spectrale et statistique pour quantifier les flux turbulents de quantité de mouvement et de chaleur sensible, pendant la nuit, pour une durée de moyenne de l'ordre de 13 minutes. L'état de stratification de la couche de surface a été pris en compte et déterminé par la théorie de similitude de Monin-Obukhov. Les mesures nocturnes effectuées et l'application de la théorie de Kolmogorov ont permis de déduire les taux de dissipation de l'énergie et la taille des tourbillons à 5,5 m d'altitude. Ce travail a également conduit, par l'analyse chromatographique en phase gazeuse couplée à la spectrométrie de masse, à l'identification, en mangrove, de composés organiques volatils soufrés, des organohalogénés, des BTEX, ... L'ensemble de ces résultats servira ultérieurement à alimenter les modèles de dispersion spécifiques liès aux écosystèmes étudiés
The presence of obstacles met in natural environment by the flow, influences the dispersion of air pollutants which it carries. This thesis, based on spatiotemporal micro-meteorological measurements in tropical region, aims at studying the dispersion of compounds emitted by the ecosystem mangrove according to the weather conditions. At a daily scale, the meteorological analysis reveals, besides the presence of Trade Winds, the existence of thermal flows of which nocturnal thermodynamic parameters have been defined. The field observation has shown that the weak intensity of the wind disadvantages the dispersion of compounds emitted during the night. At a finer scale, the existence of a spectral gap separating large scale phenomena of those related to turbulence has been demonstrated. These last ones were treated by spectral and statistical approaches to quantify the turbulent fluxes of momentum and sensible heat during the night, for an averaged duration of 13 minutes. The stratification of the surface layer has been considered and determined by Monin-Obukhov similarity theory. The measurements acquired a night and the application of Kolmogorov theory allowed us to deduct the dissipation rate of energy and the size of the vortices at 5.5 meters in height. This work has also led us, by gas chromatography coupled to mass spectrometry, to identify, in mangrove, sulphurated volatil organic compounds, organohalogen, BTEX, ... Ali these results will later serve to feed dispersion models related to the studied ecosystem

This thesis examines pond aquaculture as a development strategy in the Philippines, with particular reference to its impact on the local environment and the livelihoods of local people.
A theoretical framework is provided by recent literature in development studies and human geography, which attempts to move away from an essentialist and ethnocentric development praxis, and towards a locally-based, participatory process of empowerment. From the perspective of such 'alternative' development ideas, orthodox strategies involving modernization, formalization of economic activities, and resource mobilization, can be reassessed.
The promotion of pond aquaculture--and the widespread mangrove deforestation associated with it--is shown to be a strategy endorsed and supported by national and international development agencies. What is often overlooked, however, is the local ecological and economic importance of mangrove ecosystems. This study examines the effects of mangrove removal and fishpond development on the entitlements of people in three coastal communities in the Philippines. Aquacultural development is shown to have detrimental effects on the integrity of the coastal ecosystem and the livelihoods of certain groups of local residents; a rich common property resource is converted into a privately-owned system of cultivation. While benefits accrue to those with access to the capital necessary for the construction of fishponds, the costs of development are borne largely by mangrove gatherers and artisanal fisherfolk, whose share of a diminishing resource base is steadily declining. For these marginal groups, aquaculture is shown to provide few compensating economic benefits.
The study supports, through concrete local evidence, the criticisms made of orthodox approaches to development, and the need to construct attitudes and strategies which are more attuned to local sustainability and equity.

Orientador: Fosca Pedini Pereira Leite
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: As algas do gênero Bostrychia, juntamente com outras algas, formam uma comunidade que está presente nos costões, bem como associadas com pneumatóforos nos manguezais. Sua estrutura complexa propicia a retenção de sedimento, água e matéria orgânica, bem como um mosaico de algas que varia temporalmente e, formando microhabitats que são refúgios para a fauna. O objetivo deste estudo é analisar a distribuição da fauna associada à comunidade de algas Bostrychietum e os fatores que influenciam a sua distribuição. Foram amostrados dois costões rochosos e uma área de manguezal no litoral norte do Estado de São Paulo. Nestes locais, foram realizadas quatro coletas durante o ano de 2012, sendo obtidas amostras para a identificação da fauna associada e para a análise de fatores ambientais (teor de matéria orgânica e granulometria do sedimento). O peso da amostra (peso seco da alga + do sedimento) foi usado para o cálculo da densidade de indivíduos. A composição das algas variou nos meses amostrados em todos os locais. Amostras do mesolitoral apresentaram mais espécies de algas associadas que as do supralitoral. Tal fato influenciou a distribuição da macrofauna, uma vez que a diversidade diminuiu nas amostras com menos espécies de algas. Os moluscos e anfípodes onívoros foram abundantes em todas as amostras, sendo os anfípodes Hyalidae dominantes. A interação entre as variações sazonais das algas da comunidade e o hidrodinamismo modula a distribuição da macrofauna nos costões. No manguezal, os pneumatóforos mais próximos da água apresentaram diferenças com relação às amostras do interior do mangue quanto à composição de algas e da fauna associada. O Bostrychietum é, portanto um microecossistema com vários fatores modulando as interações entre as espécies, sendo necessárias maiores investigações das relações existentes entre as espécies e os fatores ambientais atuantes
Abstract: The algae of the genus Bostrychia together with other algae form a community present in rocky shores as well as associated to pneumatophoresin mangroves. Both their complex structure with ramifications which provide sediment, water and organic matter retention and the algae mosaic that varies seasonally foster microhabitats which are refuges for the fauna during low tide periods. The aim of this study was to evaluate the distribution of fauna associated wih algal community Bostrychietum and the factors that influence their distribution.Two rocky shores and one mangrove area in the Northern shore of São Paulo State were sampled. In these sites four samplings were made during the year of 2012: samples were collected for the identification of the associated fauna and for the analysis of environmental factors (organic matter content and sediment grain size). The weight of the sample (alga dry weight + sediment dry weight) was used to calculate the density of individuals. The algal composition varied through the sampled months as well as in relation to distance from the sea. Samples located in the mesolittotal presented more algal species associated. Such fact influenced macrofauna distribution since diversity was lower for samples containing less algal species. Omnivore mollusks and amphipods were abundant in all samples, Hyalidae amphipods being dominant.The interaction between seasonal variations of the algae in the community and the hydrodynamics modulates the distribution of macrofauna on the rocky shores. In the mangroves, those pneumatophores closer to the water presented diferences in relation to the composition of algae and associated fauna compared to samples from inner parts of the mangrove. Thus, Bostrychietum is a microecosystem with many factors modulating the interactions between species, making further investigation on the existing relationships between species and the operating environmental factors necessary
Mestrado
Ecologia
Mestre em Ecologia

Mangroves are intertidal ecosystems found along the tropical and subtropical coastlines.

Though globally recognised as ecosystems of ecological, biological and economical

remarkable importance, these ecotone formations are characterised by a continuously

increasing anthropization. However, very little studies have been focused on the impact of

various anthropogenic activities on the mangrove vegetation structure.

We have firstly (a) assessed the commercial and subsistence utilization of mangrove

wood products in the Littoral region (Cameroon estuary). Then, we have confronted the

subsistence usages of mangrove wood products in the Southern region (close to the mouth of

the Nyong River and Mpalla village (Kribi)) in comparison with the Littoral region. By doing,

we have compared the local residents‟ perceptions on environmental changes that occurred

within the two regional mangrove forests. Also, we have (c) studied the structural dynamic of

mangrove vegetation neighbouring the Douala city (Cameroon). Always in the vicinity of this

town, we have (d) reconstructed the original structure of largely disturbed mangrove forests.

Moreover, we have (e) map the mangrove structure in a non peri-urban setting located within

the Cameroon estuary. Here, we have finally (f) analysed the spatial distribution of a black

mangrove namely Avicennia germinans (L.) Stearn.

Our results underlined an excessive utilization of mangrove wood products in the

Cameroon estuary. We have showed that the frequency of mangrove harvesting was relatively

fewer in Kribi (Mpalla) and the mouth of the Nyong River. The local people inhabiting these

two localities perceived mangroves as less degraded areas. In contrast, those established

within the Cameroon estuary stated that mangroves were largely disturbed. When combining

the local people statements with our field observations, we recorded that it a complex mix of

causes (e.i. clear-felled corridors, agriculture, sand and gravel extraction, over-harvesting and

anarchic urbanization) that have led to the largely degradation (vegetation and sediment) of

the peri-urban mangroves in Cameroon. A diachronic analysis (1974, 2003, 2009) of their

coverage revealed that over the 35-year period, mangrove had decreases in cover of 53.16%

around Douala. We have also showed that in the peri-urban settings, wood harvesting was

commonly applied on the structurally more complex (highly dense stands neighbouring the

habitations) mangrove forests (Mboussa Essengue) and, in a lesser extent, on the structurally

more developed mangrove stands (fewer dense stands faraway from Douala). On the other

hand, the mapping analysis of the non peri-urban mangroves (distant from Douala) has

revealed that the structure of these intertidal forests was relatively less impacted. In the

Cameroon estuary, we also showed that A. germinans trees were randomly distributed on

almost one-half of the sampling plots and clumped at some scales on the remaining plots.

Accordingly, this species might play a significant role in the recovery process of artificial

gaps found in the non peri-urban areas.

The multi-disciplinary approach employed in this study has allowed a better

understanding of the direct and indirect impacts of anthropogenic activities on the mangrove

vegetation structure in Cameroon. These results constitute a fundamental data base quite

useful for the multi-temporal monitoring of these littoral ecosystems perpetually disturbed.

The application of similar approach in other mangroves facing high anthropogenic pressures

appears important.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished

The southern coast of Shoal Bay, near Darwin, Northern Territory is a small, well vegetated chenier plain. Chenier plains are prograded coastal mudflats that support a number of long narrow ridges formed from sand and shell debris, that run parallel to the coast. Mangrove communities on the mudflat occur in zones, also parallel to the coastline, indicating species preference for protection, depth and duration of tidal inundation and level of salinity. Chenier plains are thought to be formed through fluctuations in sediment supply resulting in, episodic coastal progradation, and coastal erosion and ridge deposition above the level of high tide. Some of the literature suggests that progradation may be aided by the seaward mangrove zones trapping sediments, while erosion of the mudflats and subsequent ridge formation can be attributed to high energy storm activity, such as that of a tropical cyclone. This study is involved with examining the recent history of the chenier plain at Shoal Bay, in regard to the effects of cyclone Tracy, which struck the area on December 25, 1974. The storm devastated large areas of the central mangrove zones, those of Bruguiera, Ceriops and Rhizophora, mostly by windthrow. The seaward mangrove zones, such as that of Avicennia, and the landforms were mostly unaffected by the storm winds, and the storm surge associated with the cyclone was relatively small, as it occurred in conjunction with a neap high tide. The overall effects of cyclone Tracy on the chenier plain were much less than those described for other storms in the literature. All of the changes that have occurred on the Shoal Bay chenier plain over the period examined can be explained by normal wave and tide action, and do not require a high energy event.

要旨pdfファイル:タイトル「原生巻貝のタフォノミー:西表島の現生マングローブ林に生息するTerebralia palustrisを例に」
Kyoto University (京都大学)
0048
新制・課程博士
博士(理学)
甲第7672号
理博第2057号
新制||理||1095(附属図書館)
UT51-99-G266
京都大学大学院理学研究科地球惑星科学専攻
(主査)教授 前田 晴良, 教授 瀬戸口 烈司, 教授 増田 富士雄
学位規則第4条第1項該当

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This work was carried out from August 2007 to July 2011, in Itabora?, RJ, Brazil, and aimed to identify the Calliphoridae species exist in a mangrove swamp, verifying which are the predominant species, highlighting the proportions of males and females, and also analyzing the influence of abiotic factors such as temperature, humidity and moon phases, and also providing an analysis of the abundance, richness, diversity and similarity between the periods of sampling, ecological relationships between species of the same family and the ecological relationship between Calliphoridae and Phoridae parasitoids in Guapi-Mirim Environmental Protection Area, (Guapi-Mirim EPA) in the same city. Semiweekly collections were carried out over 48 months (96 collections). The traps were suspended at a height of 1.20 m above the ground for a period of 48 hours for each collection. To trap and collect the flies, four plastic traps (35 cm x 15 cm) were placed 100m apart each other in the studied area. The bait used was based on fish (sardine) in decomposition. The insects caught were killed by asphyxiation with 70% ethanol inside the trap. After asphyxiation all specimens were put into plastic pots containing 70% ethanol. The specimens were taken to the Laborat?rio de Transmissores de Leishmanioses (Setor de Entomologia M?dica e Forense) - IOC/FIOCRUZ, RJ, where they were separated by the collection day, counted and then identified using a stereoscopic microscope and the dichotomous keys for families and species. The abundance of Calliphoridae flies was statistically analyzed using the Statistica 7.1 program (StatSoft 2005) for the non-parametric test Kruskal-Wallis one way ANOVA (p< 0.05). Also the Kendall Tau Correlation test, Mann-Whitney (significance of 95%; p<0.05) and chi-square test (?2) were used to analyze. The Shannon-Wiener diversity index, Bray-Curtis similarity and Euclidean Distance were used. A total of 4,531flies were collected. These flies belonged to ten (10) species of the Calliphoridae family: Chrysomya megacephala (Fabricius, 1794) (86.40%), Chrysomya albiceps (Wiedemann,1819) (5.72%), Cochliomyia macellaria (Fabricius, 1775) (4.94%), Chrysomya putoria (Wiedemann, 1818) (2.10%), Lucilia eximia (Wiedemann, 1819) (0.30%), Cochliomyia hominivorax (Cocquerel, 1858) (0.22%), Chloroprocta idioidea (Robineau-Desvoidy, 1930) (0.20%), Hemilucilia segmentaria (Fabricius, 1805) (0.04%), Hemilucilia semidiaphana (Rondani, 1850) (0.04%), Lucilia cuprina (Wiedemann,1830) (0.04%). The species C. megacephala was the one that presented the greatest abundance. Spring was the preferred season for all species; temperatures between 30.5 and 32.40C and relative humidity between 56.8 and 61.7% were considered those where there was a frenzy of oviposition; the full and new moons were the phases during which there was a higher occurrence of flies; Megaselia scalaris occurred more frequently in the most abundant Calliphoridae species in the same season of the year thus allowing greater dispersion of eggs; Calliphoridae species had a higher rate survival with increased food resources resulting from the polluting activity
Este trabalho foi realizado entre agosto de 2007 e julho de 2011, no Munic?pio de Itabora?, RJ, Brasil, e teve como objetivo identificar as esp?cies de Calliphoridae existentes em uma ?rea de mangue, quantificar as predominantes, destacando as propor??es de machos e f?meas, e tamb?m analisar a influ?ncia de fatores abi?ticos, tais como temperatura, umidade do ar e fases lunares; e ainda relacionar a abund?ncia, a riqueza, a diversidade e a similaridade entre os per?odos de coletas, rela??es ecol?gicas entre as esp?cies da entomofauna da mesma fam?lia e a rela??o ecol?gica entre Calliphoridae e Phoridae parasit?ides dentro da ?rea de Prote??o Ambiental de Guapi-Mirim (APA de Guapi-Mirim), em Itabora?. Durante 48 meses, foram realizadas 96 coletas, uma a cada 15 dias. Em todas as capturas, foram utilizadas armadilhas confeccionadas em recipiente pl?stico com 35 cm de altura e 15 cm de di?metro. Cada uma das quatro armadilhas foi suspensa a uma altura de 1,20 m do solo contendo 100g de isca de peixe (sardinha) em decomposi??o por um per?odo de 48 horas. Ap?s cada captura, todos os esp?cimes foram mortos no interior das armadilhas por asfixia utilizando etanol 70%. Em seguida todos os indiv?duos foram acondicionados em potes pl?sticos, contendo etanol a 70% e encaminhados ao Laborat?rio de Transmissores de Leishmanioses (Setor de Entomologia M?dica e Forense), IOC-FIOCRUZ, RJ, em seguida todos os esp?cimes foram separados por dia de coleta, identificadas e quantificadas. Para tal procedimento utilizou-se um microsc?pio estereosc?pico e chaves dicot?micas para a identifica??o da fam?lia e das esp?cies. As an?lises estat?sticas foram feitas utilizando o programa estat?stico Statistica 7.1 (STATSOFT, 2005), atrav?s do teste de Kruskal- Wallis one way ANOVA, teste de qui- quadrado (?2), Mann-Whitney e correla??o de Kendall Tau (p<0,05). Foram utilizados os ?ndices de diversidade de Shannon-Wiener e similaridade de Bray-Curtis, assim como a Dist?ncia Euclidiana. Foram capturadas 4531 moscas pertencentes a dez (10) esp?cies da fam?lia Calliphoridae: Chrysomya megacephala (Fabricius, 1794) (86,40%), Chrysomya albiceps (Wiedemann,1819) (5,72%), Cochliomyia macellaria (Fabricius, 1775) (4,94%), Chrysomya putoria (Wiedemann, 1818) (2,10%), Lucilia eximia (Wiedemann, 1819) (0,30%), Cochliomyia hominivorax (Cocquerel, 1858) (0,22%), Chloroprocta idioidea (Robineau-Desvoidy, 1930) (0,20%), Hemilucilia segmentaria (Fabricius, 1805) (0,04%), Hemilucilia semidiaphana (Rondani, 1850) (0,04%), Lucilia cuprina (Wiedemann,1830) (0,04%). A esp?cie C. megacephala foi aquela que apresentou a maior abund?ncia, a primavera foi a esta??o do ano em que todas as esp?cies mostraram maior prefer?ncia; as temperaturas compreendidas entre 30,5 e 32,40C e a umidade relativa do ar entre 56,8 e 61,7% foram consideradas aquelas onde houve frenesi de oviposi??o; nas luas cheias e novas houve maior ocorr?ncia de moscas capturadas; Megaselia scalaris se utilizou de esp?cies abundantes nas mesmas esta??es do anos em que ela ocorreu com maior frequ?ncia, possibilitando assim maior dispers?o de ovos; a maior disponibilidade de recursos alimentares resultantes da atividade poluidora tempor?ria ofereceram uma melhor condi??o de sobreviv?ncia para as esp?cies os Calliphoridae.

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O presente trabalho buscou saber os prejuízos socioambientais decorrentes da eliminação do ecossistema manguezal, e se o Estado de Pernambuco está cumprindo o disposto na legislação ambiental quanto ao andamento do procedimento administrativo para supressão de vegetação considerada de Preservação Permanente. Como hipóteses, a pesquisadora elencou duas: considerando todos os benefícios decorrentes das funções ecológicas do ecossistema manguezal, o estado de Pernambuco perde drasticamente em termos de biodiversidade, que consequentemente desencadeia prejuízos socioambientais; e o Estado de Pernambuco incorre em ilegalidade e inconstitucionalidade na emissão de leis autorizativas para supressão de manguezal, descumprindo ainda princípios do direito ambiental. De acordo com os objetivos da pesquisa, realizou-se uma pesquisa documental/bibliográfica, quanto à legislação protetiva, à administração pública e aos procedimentos administrativos, inclusive ao nível nacional, para autorização de interferência no ecossistema e uma atualização das leis ordinárias com relação à autorização de supressão de áreas de manguezal no site da Assembleia Legislativa do Estado de Pernambuco. Tendo em vista que os pescadores, considerados comunidade tradicional, estão intrinsecamente ligados ao manguezal, foram realizadas 22 entrevistas com pescadores da colônia Z – 8, situada no município de Cabo de Santo Agostinho e 23 entrevistas com pescadoras da colônia Z-12, situada no município de Ipojuca. A atualização das leis autorizativas culminou com o resultado de 601,00 ha de manguezal autorizados a suprimir, o que desencadeou um verdadeiro desastre socioambiental, a partir da violação dos princípios ambientais e as disposições legais referentes.
The present study sought to know the social and environmental losses arising from the removal of mangrove swamp, and the state of Pernambuco is meeting the requirements of environmental legislation when the progress of the administrative procedure for removal of considered Permanent Preservation vegetation. As hypotheses, the researcher has listed two: considering all the benefits of the ecological functions of the mangrove ecosystem, the State of Pernambuco dramatically lose in terms of biodiversity, which in turn sets off sociambientais losses; and the State of Pernambuco incurs illegality and unconstitutionality in issuing authorization laws for suppression of mangrove swamp, still not complying with principles of environmental law. According to the research objectives, there was a documentary /bibliography research, about the protective legislation, public administration and administrative procedures, including the national level to permit interference in the ecosystem and an update to the ordinary laws regarding the authorization of removal of mangrove areas in Pernambuco State Legislative Assembly website. Having in mind that the traditional community - fishermen who are intrinsically linked to the mangrove swamp, there were 22 interviews with fishermen from the Z - 8 colony, located in the municipality of Cabo de Santo Agostinho and 23 interviews with fishers from the Z -12 colony, in the municipality of Ipojuca. Updating authorization acts culminated with the result of 601.00 ha of mangrove swamp allowed to suppress, which triggered a socioenvironmental disaster from the violation of environmental principles and legal provisions concerning.

Urban development and human encroachment on the natural habitats along the coastline of Florida combined with invasive exotic pressures have resulted in the fragmentation and degradation of habitat quality within Broward County. Native habitats have been significantly altered and fragmented to a fraction their previous size. With loss of habitat area and quality, isolation of breeding populations and anthropogenic pressures, it is important to determine species composition and habitat utilization in order to conserve the remaining biological diversity. It was the intent of this study to determine the small mammal species’ population structure and habitat utilization by season in the four sampled habitats. Previously undocumented species and/or extralimital populations were predicted prior to sampling. John U. Lloyd Beach State Park in Dania Beach, Florida is an understudied location for small mammals. This study surveyed four terrestrial habitats for small mammal species using live trapping and mark/recapture techniques. Data were collected monthly over the span of thirteen months to determine habitat use from maritime hammock, mangrove swamp, coastal dune and ruderal habitat types to determine species composition and mass of individual captures and recaptures. Trapping (3749 trap nights) produced twenty-four captures (including recaptures) in two of the four habitat types: maritime hammock and coastal strand. No animals were captured in the mangrove swamp or ruderal habitats, both of which were dominated by invasive Australian pine (Casuarina equisetifolia) monocultures. Post study, a large habitat restoration project restored the habitats impacted by invasive exotic flora. This survey serves as a baseline for small mammals in the park, documenting the pre-restoration habitat use and species composition. Future study to determine changes in species composition post-restoration is recommended.

The Florida Everglades ecosystem is threatened by human development, increased pollution, freshwater scarcity, and invasive species; factors that have negatively impacted the Everglades and native species health and populations. Man-made canals and levies have redirected the natural flow of fresh water from Lake Okeechobee into the Florida Everglades, starving central and south Florida ecosystems of necessary fresh water and nutrients. Through the efforts of the Comprehensive Everglades Restoration Project (CERP), freshwater is being redirected back into central and south Florida, returning the sheet flow of water back into the Everglades. Monitoring species abundance in the Everglades is a beneficial conservational tool for assessing restoration efforts from CERP. As a semi-aquatic apex predator, river otters (Lontra canadensis) are a useful health bio-indicator for the Florida Everglades. In order to conduct future population studies of river otters in the Florida Everglades, it must first be ascertained where they can be found and what time of year they are most likely to be sighted. For this study, Moultrie infrared game cameras were used to photograph the presence or absence of river otters within the five main habitats in the Everglades; the pinelands, hardwood hammock, cypress swamp, marsh prairie, and mangrove estuary at two protected areas in the Florida Everglades (Big Cypress National Preserve and Fakahatchee Strand State Park). River otters were most frequently sighted in the hardwood hammock habitat, but were also found in the cypress swamp. The large majority of river otter sightings occurred during dry season, which is thought to be a function of restricted water availability and aquatic mobility. Future population studies of river otters would be most productive in the hardwood hammock and cypress swamp habitats during dry season. Game camera images along with field opportunistic sightings, resulted in a variety of species documented. This provided valuable information of species richness and distribution within and amongst the habitats. The hardwood hammock was found to be the most species rich habitat, having over half the species observed in the study in this habitat. The Aves class was the most abundantly observed in the Everglades, and was most frequently sighted during the dry season. As a refuge for migratory birds, the Everglades house the majority of bird species during the winter months, which occur during dry season. The Aves class was most frequently sighted in the pinelands habitat during dry season. This habitat, being the highest in elevation and therefore the driest, shows a stronger resemblance to most northern bird habitats then does the water-saturated wetlands found throughout the Everglades. The mangrove estuary was the most commonly occurring outlier, having the least species overlap when compared to the other habitats. All other habitats in the Everglades are freshwater wetlands, while the mangrove estuary is a brackish environment, which limits the species that are unable to tolerate saline conditions. Further studies of species abundance throughout the Everglades will aid in monitoring CERP restoration efforts over time.

Because of the variety of ecological and economic functions they perform, estuaries and mangrove swamps are recognised as amongst the most valuable habitats on earth. However, estuaries and related mangrove swamps are threatened by human expansion and exploitation which leads to changes in land cover change within and surrounding these sensitive ecosystems. Such land cover changes can either have desirable or undesirable effects on natural ecosystems. Examples of undesirable impacts of land cover change include soil erosion and degradation, the removal of indigenous vegetation for human development, and the pollution of water. Without an effective means of identifying, monitoring and managing land cover changes over time, these sensitive ecosystems face a bleak and uncertain future. The researcher sought to determine whether wetland bird species could be used as an effective method of monitoring the environmental health of estuaries and mangrove swamps. In particular, the research sought to determine whether analysing fluctuations in the populations of wetland bird indicator species, as evident in the CWAC Bird Census data, could assist in monitoring and assessing undesirable and desirable land cover changes within the Mgeni Estuary and Beachwood Mangrove Swamps. An examination of the archival aerial imagery of the study area for the years 1991, 1997, 2003 and 2008 provided by the University and private companies, revealed significant changes in land cover over the last two decades. The land cover changes identified represent an actual decline or increase in the suitable foraging, roosting or reproductive habitats of wetland bird indicator species within the study area. The research focused on investigating whether fluctuations in wetland bird populations can be correlated with the recorded changes in land cover over the last two decades. The research discovered a direct and comprehensive link between fluctuations in specific populations of wetland bird indicator species and the land cover changes identified within the study area over a 20 year period.
Thesis (M.A.)-University of KwaZulu-Natal, Durban, 2010.

Estuarine habitats along the temperate south-eastern shores of Australia are generally made up of salt marsh, mangrove forests and seagrass beds. In urban areas these habitats have been progressively fragmented as a result of population increase and industrial expansion. Salt marshes in particular have been vulnerable to urban expansion and reclamation because of their close proximity to densely populated areas, while mangrove forests have been less often reclaimed because of frequent tidal inundation. The effect of reclamation of salt marshes on the biotic assemblages and functioning of mangrove forests with an adjacent salt marsh, park or bund wall was examined at nine separate locations on the Parramatta River, Sydney NSW. A mensurative approach was used to describe the patterns of distribution and abundance of macro fauna at several temporal and spatial scales. The implications for management are that salt marshes are an integral part of estuaries, and smaller patches of salt marsh are just as important as larger patches in maintaining the diversity of faunal assemblages and ecosystem functioning in mangrove forests in urban areas

碩士
國立中央大學
應用地質研究所
107
Mangrove swamp is an important intertidal wetland ecosystem with high primary productivity, abundant detritus, and also rich in organic carbon. In order to understand the process and mechanism of organic materials during burial and preservation processes in a mangrove swamp, we evaluated the mineralogy, total organic carbon (TOC %), Rock-Eval pyrolysis, water quality, as well as biomarker to analyze the depositional characteristics. Study site was a mangrove swamp in Tamsui, NW Taiwan. In this area, we chose two sampling sites, F (Far-off land) and N (Near land). Samples were collected from different depths (0-5cm, 5-15cm, 15-30cm, 30-40cm). We found that TOC varied between 0.17% and 0.8%, Tmax values were 364 to 443oC; S1 and S2 were ranging from 0.08 to 0.19 mg HC/g rock and 0.07 to 0.47 mg HC/g rock respectively. Hydrocarbon potential was immature in all samples. Far-off land samples exhibit higher total organic carbon content and S2 value than near land. Major organic matters we found in far-off land are algae and zooplanktons. However, organic materials in surface and bottom layer of the near land are terrigenous and marine materials, respectively. In addition, water quality data showed that both areas were influenced by sea water. F area also exhibited higher dissolved oxygen and electricity conductivity. Mineralogy from XRD indicated that all of the soils were characterized by quartz, feldspar, illite, kaolinite and chlorite. Major clay mineral in F samples is illite. Besides, illite and kaolinite are major clay minerals in N samples. Finally, biomarker analysis indicates an oxic environment of all samples. Based on the above analyses from different localities and depths, we found that the distance to the sea affects the source of organic materials, and redox conditions further affect the accumulation of organic materials.

Nitrogen fixation of blue-green algae associated with Avicennia marina (Forssk.) Vierh. pneumatophores and wet and dry surface sediments were investigated in the Mgeni Estuary mangrove swamp by means of the acetylene reduction technique. Optimum partial pressures of acetylene ranged from 0,15 to 0,2 atm. for the different habitats. A lag phase of 3 h was observed in all habitats, followed by a period of linear ethylene production of 42 h for the pneumatophores and 72 h for the wet and dry mat areas. An assay period of 24 h was employed in all habitats. Laboratory studies revealed percentage moisture and temperature to be the prime factors influencing ARA (acetylene reduction activity) in all habitats and rates were highest under submerged conditions and at 22˚C. Short-term variations in ARA and salinity in the wet and dry mat areas, measured at 6 day intervals, were also related to percentage moisture. High concentrations of inorganic nitrogen (between 1 and 5 mg 1-1) significantly depressed ARA in all habitats. Increases in ARA occurred with increase in light intensity up to 40 μE m -2 s-1, with negligible dark rates being recorded in the wet and dry mat areas. Significant dark rates of ARA and stimulation of ARA by sucrose in association with the pneumatophores indicated that bacteria may also be contributing to ARA in this habitat. No organic carbon stimulation was noted in the other sites. Salinity had little effect on ARA over the range generally experienced in each habitat. Field studies revealed a marked seasonal variation in ARA, with summer maxima of 78, 678 and 341 nmol C2H4 cm-2 24 h-1 associated with the pneumatophore, wet and dry mat areas respectively. This coincided with maximum nitrogen-fixing blue-green algal numbers, temperature, light intensity and day length. No seasonal variations in organic carbon, inorganic nitrogen, salinity, percentage moisture or bacterial numbers were apparent. Rates of bacterial ARA associated with decomposing litter of A. marina were highest under exposed conditions and reached a maximum of 25 935 nmol C2H4 g dry wt -1 24 h -1 after 3 weeks. Maximum rates of ARA under submerged conditions of 5394 nmol C2H4 g dry wt -1 24 h -1were reached after 4 weeks of decomposition. An increase in percentage nitrogen occurred during decomposition and was greatest under submerged conditions. Rates of decomposition were highest under exposed conditions. It was estimated that nitrogen fixation by blue-green algal communities supplies 23,8% of the annual nitrogen requirements of the mangrove swamp.
Thesis (M.Sc.)-University of Durban-Westville, 1987.

碩士
國立臺灣師範大學
生物學系
84
ABSTRACT The purpose of this work is to find out the reproductivephysiology of female Uca vocans borealis in the Tanshui Mangrove Swamp of Northern Taiwan. In reproductive season(March-August), more than eighty percent of the female Uca vocans borealis collected in the Tanshui mangrove swamp of northern Taiwan were found to carry eggs. On the contrary, no eggcarrying crabs were found in nonreproductive season (October- December).Females collected either on springtide or neaptide, were tentatively categorizedin four groups:carried yellow, brown, black eggs and noneggcarrying. Each category contributed about 25%. Different developing stages of embryo were foundamong crabs carried brown eggs. The embryos of crabs carried black eggs nearly reached hatching stage. Therefore, it is suggested that the spwaning and releasing of Uca vocans borealis is not synchronized and not correlated to the tide. The incubation time of the carried eggs was 15-20 days according to the record of the raised crabs on the field and in the laboratory. It is estimatedthat the reproductive cycle of Uca vocans borealis is about 20 days. The GSI offemales of the nonreproductive season was about a half of that of the reproductive season.The ovaries of crab carried black eggs contained more protien and fat. (107.3-187.4 ng/g of ovary;312.3-377.2 ng/g of ovary). The protein content of hepatancreas of crab carried brown eggs did not show sibnificant variation(p>0.05) during the reproductive season. However, the crabsof nonreproductive season contained less protein (68.57-89.9mg/g of hepatopancreas), and nonreproductive season contained similar amounts of fat.During reproductive, the hepatopancreas of crab carried black eggs contained more protein and fat(102.8-148.7 mg/g of hepatopancreas ; 102.8-346.3 mg/g ofhepatopancreas) than those crabs carried brown or yellow eggs.The progesterone-like substance was detected in the hemolymph of the female crabs. The hemolymphic progesterone-like substance levels of the nonreproductive season(0.051-0.086 ng/g of wbw) were lower than that of reproductive season (0.121-0.464 ng/g of wbw). The progesterone-like substance was also detested by HPLC and RIA in the purified steroid residues of ovary, hepatopancreas and hemolymph.The hemolymph contained least amout of progesterone- like substance (0.003-0.520ng/g of wbw). Among ovaries, crab carried yellow eggs had more progesterone- likesubstance(0.117-0.521 ng/g of ovary) than crab carried brown eggs(0.067-0.361 ng/g of ovary). The ovaries of crab carried black eggs had least amount (0.003-0.071 ng/g of ovary). The function of hormones of crustaceans, including theprogesterone-like substance of Uca vocans borealis, isdiscussed in this work.

碩士
國立東華大學
自然資源管理研究所
86
The effect of nutrients on the growth of dwarf Kandelia candel in the Chuwei mangrove swamp was studied. In addition to the field fertilization experiment, seasonal changes of nutrient content in leaf tissues, soil and water in the swamp were also examined in this study. Growth parameters, i.e., tree height, canopy diameter, number and length of young shoots, and the N and P content in leaf tissues were significantly increased in fertilization treatments containing nitrogen. No difference was found between phosphorus and control treatments. This indicates that nitrogen is the nutrient limiting factor for the growth of dwarf K. candel in the Chuwei mangrove swamp. According to the analyses of nutrients in the hydrological environment, inorganic nitrogen and organic matters in the inundation tide could be the main nitrogen sources for the swamp. Therefore, frequency and duration of tidal inundation not only affect the nitrogen supplement to the swamp, indirectly, also affect the texture composition and chemical properties in the soil. The elevation of the area where the dwarf forest grows in the Chuwei mangrove swamp is higher than the average height of high tide. This differs from the tidal creek forest whose height of growing area is lower than the average height of high tide. Therefore, the frequency discrepancy of tidal inundation is probably the reason of nutrient distribution causing difference in growth response between the dwarf and tidal creek forest. The damage caused by typhoon on plant, and the difference in burrowing activity of crabs between the dwarf and tidal creek areas could also be some important effects to limit the growth of K. candel and the deficiency of N in the dwarf forest area in the Chuwei mangrove swamp.

碩士
國立臺灣大學
漁業科學研究所
86
In the mangrove estuary of the Tanshui River in northern Taiwan, the comp onents of the detrital food chain, including the particulate organic matter (P OM) of sea water, river water and sediment, primary producers, deposit feeders , and a suspension feeder, were examined at three sites using stable carbon an d sulfur isotopes to reveal the possible flow of organic matter. The fresh le aves of the vascular plant Kandelia candel had a δ13C as -26.2 %, indicating that it is a C3 plant. K. candel had a δ34S value of +5.6 %. The δ13C leve l of particulate organic matter (POM) of sea water (collected at flood tides) averaged -23.5 %, and that of river water (collected at ebb tides) was -24.6 %, whereas benthic microalgae had a δ13C level of -19.4 %. The δ13C and δ3 4S levels of sediments ranged from -26.1 to -24.6 % and +5.0 to + 9.1 %, respe ctively, and were close to the values of the mangal leaves, suggesting that th e organic source of sediments comes mainly from the vascular plant K. candel. The isotopic values of the sediment did not significantly differ according to the site (3 sites) or the depth (2 depths), but differ according to particle size. These results indicate that particle size is a key factor in harboring different sources of organic matter. In polychaetes, the deposit feeder (the nereid Neathes glandicincta), and the suspension feeder (the sabellid Laonome albicingillum) had δ13C values ranging from -21.4 to -20.8. %, and from -22.2 to -21.9 %, respectively; whereas δ34S values ranged from +8.6 to +13.8 %, a nd +10.2 to +11.7 %, respectively. The two polychaetes significantly differed in their stable isotopic compositions and N. glandicincta was at slightly hig her trophic rank than L. albicingillum. In addition, the nereids exhibited a greater variation in the sources of the detrital organic matter than the sabel lids. Based on the δ13C and δ34S values, the crabs were well separated into three groups, also according to the sites. The river living crabs containing Uca arcuata and U. lactea had δ13C values averaged -15.5 % and δ34S values averaged +13.1 %, the creek living crabs containing U. arcuata again and U. b orealis had -19.4 % and +11.7 %, and the creek living Helice. formosensis as - 21.5 % and +9.9 %, respectively. Such a discrepancy found in the detritivores may be attributed to their different feeding sites and modes. The present st udy suggests that the detritus consumed by the two studied polychaete species and H. formosensis are probably from K. candel and POM of water. As regards t he food of the crabs, both benthic microalgae and Phragmites commuuis are poss ible sources and the relative importance of the two sources depends on where t he crabs live. In conclusion, detrtus in the study mangrove swamp are disting uishable from one another and detritivores differentiate their food sources fr om a common pool.