Modelo de simulación de la comunidad de peces en el área natural protegida Laguna de Términos, Campeche, México
Terminos Lagoon is a protected area in Campeche, México. This region has economical, social and scientific importance because it has high level of biodiversity, abundance of economic resources, fisheries activities focused mainly on shrimp, food produccion by agriculture, oil industry (exploration a...
| Autor: | |
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| Tipo de recurso: | tesis doctoral |
| Estado: | Versión publicada |
| Fecha de publicación: | 2006 |
| País: | México |
| Institución: | Universidad Autónoma Metropolitana |
| Repositorio: | Repositorio Institucional de la UAM Iztapalapa |
| Idioma: | español |
| OAI Identifier: | oai:bindani.izt.uam.mx:f4752h024 |
| Acceso en línea: | https://doi.org/10.24275/uami.f4752h024 |
| Access Level: | acceso abierto |
| Palabra clave: | info:eu-repo/classification/LEM/Biodiversity conservation -- Laguna de Terminos (Campeche) info:eu-repo/classification/LEM/Freshwater fishes -- Laguna de Terminos (Campeche) info:eu-repo/classification/LEM/Conservación de la biodiversidad -- Laguna de Términos (Campeche) info:eu-repo/classification/LEM/Lagoons -- Ecology -- Laguna de Terminos (Campeche) info:eu-repo/classification/LEM/Lagunas -- Ecología -- Laguna de Términos (Campeche) info:eu-repo/classification/LEM/Peces de agua dulce -- Laguna de Términos (Campeche) info:eu-repo/classification/cti/3 |
| Sumario: | Terminos Lagoon is a protected area in Campeche, México. This region has economical, social and scientific importance because it has high level of biodiversity, abundance of economic resources, fisheries activities focused mainly on shrimp, food produccion by agriculture, oil industry (exploration and explotation) and aquaculture initiatives. The concern about the environmental and biodiversity level decline due to antropogenic activities has been reflected in many scientific contributions, however, it is necessary to continue with research on resource assessment, environmental and ecological monitoring leading to develop management strategies for it conservation and sustainable use. The most conspicuous macro fauna into the aquatic community of this natural area are the fish. The fish community shows high abundance and diversity, wide distribution in space and time and it uses different habitats across their life cycles. This work presents an integration of the existing information for each one of the fluvial-lagoon subsystems associated to the Terminos lagoon, as well as that for the lagoon basin itself, emphasizing the dynamic models for the most important fish populations. A simulation model considering the abundance and behavior patterns of such species is developed. The environmental impact level in the region is discussed and the interchange between adjacent ecosystems with high economically important fisheries resources is compared. Therefore, the objective of this research is to develop a simulation model that depicts the most important processes of energy transference into the fish community of Terminos Lagoon considering the development of life cycles of dominant and economically important species. The results describe the environmental variability and the abundance and diversity of fish community of each one of the subsystems, whith spatial-temporal comparisons. The fish community for the natural area is represented by a total of 129 species grouped in 44 families and 102 genera. Considering the importance index and the total number of individuals with the total weight (53,694 individuals and 1,241.8 kg) of all the species captured in the five ecological subsystems, the dominant species have been identified. The dominant species represent the 81.1% in number of individuals and the 81.7% in weight of the total capture. The dominant species are: Cathorops melanopus, Diapterus rhombeus, Sphoeroides testudineus, Eugerres plumieri, Bairdiella chrysoura, Bairdiella ronchus, Archosargus rhomboidalis, Ariopsis felis, Eucinostomus gula, Chaetodipterus faber, Cetengraulis edentulus, Bagre marinus, Micropogonias undulatus and Cynoscion arenarius. For each one of the dominant species in the region, the main population parameters have been determined such as the Weigth-Length relationship, structure by length, and appearance frequency in temporal scale, the parameters of von Bertalanffy model as well as the mortality and the recruitment pattern. The abundance pattern in temporal scale is described considering the rain and dry seasons. Spatial distribution of the density is described by diagrammatic models in a geospatial scale. Also the trophic spectrum for each species is determinated by the stomach contents analysis. Hierarchic associations between the dominant species are described analizing the matrix of density by station and month by means of a cluster technique. In a first group Cathorops melanopus (CAME) is associated with Diapterus rhombeus (DIRH), Sphoeroides testudineus (SPTE) and Eugerres plumieri (EUPL), the second group is integrated by Eucinostomus gula (EUGU), Chaetodipterus faber (CHFA) and Archosargus rhomboidalis (ARRH) and the third group constitutes Micropogonias undulatus (MIUN), Bairdiella ronchus (BACH), Bairdiella chrysoura (BACH), Arius felis (ARFE), Cetengraulis edentulus (CEED), Cynoscion arenarius (CYAR) and Bagre marinus (BAMA). This allows establishing the bases for the construction of a conceptual model. Three general use strategies of the ecosystem have been identified considering the abundance patterns, length structure and the hierarchical associations. The first association shows a strategy of permanent use and considers to the set of species that develop all their life cycles within the system. They are adapted perfectly to estuarine conditions. In spite of the gear selectivity a length structure with high frequency of great lenghts is observed. Normally their habitat is clearly delimited and they have wide trophic spectrum but representative of the habitat availability. The second use strategy considers to species that development a portion of their life cycles whitin the system in advantage of environmental conditions specified by the climatic season. A climatic detonator of the migration exists. The force function is the rivers unloading with an effect on the salinity gradient in the rainy season and the water temperature in the dry season. Small lengths come in the system looking for food and refuge for growing. The third scheme of use identifies to all the species that use intensively the system but with a distribution and abundance patterns associated to particular and ephemeral environmental conditions. They are species represented better in the adjacent continental shelf and they have low tolerance to the decrese of the salinity and the increase of the water temperature. They have stricter feeding habits. This group is the most diverse. The Producer module has been incorporated in the model because is the base for the detritus food chain. The main producers are manglar and seagrass because the comparative biomass contribution. The maximum pulse of biomass contribution appears towards the initial portion of the dry season when the temperature decrease and the wind frequency of the north “nortes” is increased. In this way, the simulation model has been developed with four modules named: Producers, Residents, Cyclic visitors and Occasional visitors. The force functions in the Producers module are the sun and the tides. The simulation model let observe the increase in the biomass contribution during the dry season when the “nortes” increase, consequently the detritus production increase gradually. The Residents module considers the complete development of life cycles species whitin the system. The reproduction and recruitment are the processes that reflect the accomplishment with the environmental variability, specially the temperature. Mortality is considered of ídole natural mainly by depredation effects. The Cyclic Visitors module considers the temporal stay whitin the system, particularly by juveniles looking for food and refuge. The immigration and emigration processes are started by the precipitation like environmental detonator. The precipitation affects the salinity gradients mainly by the volume of discharge of the associated rivers. The model emphasizes that the abundance of the youthful has an answer to the environmental detonator while the adults are in a stability level. Finally, the Occasional Visitors module considers to the species that utilize the system by short time and that they present high levels of tolerance to the environmental variability but that nevertheless they preferences are toward habitat of greater environmental stability. The income to the system is conditioned by a complex interaction among environmental variables. In the model are considered the temperature, precipitation, “nortes” and discharge volume of the rivers. The simulation possibility in this module is comparatively greater, nevertheless it show the migrant income to the system in a period among the end of rainy season and the middle of the dry season. The Terminos Lagoon region has been cataloged as natural protected area with the category of flora and fauna protection by its levels of primary productivity, secondary production, diversity and abundance values of a complex biotic community and resilience capacity. However the increment in destruction and modification of diverse habitat by effect of deforestation, change in the discharge volume of the rivers, overexplotation of resources, irregular human establishments and contamination are increasing. A goal of this work is to contribute to improve the knowledge of these systems and its resources, to improve our understanding of the interaction between environmental conditions and biotic patterns, to built models that permit to predict behaviors under different conditions, and finally, to have better elements for it takes of decisions in aspects of use and conservation of systems and tropical coastal resources. The extractive and productive activities such as the fishing, agriculture and oil industry coexists in the region, therefore is necessary an integral ecological knowledge as base of decisions on economic growth politics and regional development. Among the most important points than should be observed and incorporated in management actions for conservation of these systems are the maintenance of the discharge volume of the associated rivers, and maintenance of the water quality. The great risk in this natural area is that any alteration inside the coastal plain is reflected in the structure and ecological function of these systems. Finally, it is necessary "to translate" the ecological processes to a concept of anthropocentric value (that is the one that we understand better). The natural function of these systems and its resources should be protected considering all the direct and indirect benefits to the human. The vigilance activities in the natural protected area is almost imposible because it’s territorial extension, nevertheless the support to research, environmental education and incentives programs should be increased and developed. |
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