BOOK REVIEW. Limnologia by J G Tundisi and T Matsumura Tundisi. Bicudo, CEM. Seção de Ecologia, Instituto de Botânica, Divisão do Jardim Botânico de. Buy Limnologia (Em Portuguese do Brasil) by José Galizia Tundisi (ISBN: Este livro vem preencher uma grande lacuna de livros-texto e livros de difusão. Veja grátis o arquivo Limnologia de aguas interiores impactos enviado para a disciplina de Ecologia In: C. E. Bicudo; J. G. Tundisi; M. C. B. Scheuenstuhl ( Org.). São Paulo: Escrituras Editora e Distribuidora de Livros Ltda, v. 1, p .
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The objective of this investigation was to update existing information on the bathymetry and morphometric features of the lake, using differential GPS DGPS technology for data collection, coupled to a digital echosounder. The bathymetry was based on the acquisition of 54, points, where the depth as well as the geographic coordinates were obtained. The total volume calculated for the lake was The new study allowed refinement of existing morphometric data.
Introduction Morphometry is associated with practically all physical, chemical and biological properties of lakes and reservoirs Wetzel, These properties, in turn, are fundamental to understand the functioning of aquatic ecosystems. The volume and water retention time, for example, are essential for estimating the carrying capacity for fish production, or even to detect the fate of nutrient and contaminants in a lake Sampaio et al. Fee demonstrated that the mean depth is a critical factor controlling the magnitude of primary production in most lakes.
Several authors have proposed that lake area is a determinant parameter to define the depth of the thermocline Acta Limnol. The shape of a given lake or reservoir regulates the sedimentation and oxygen dynamics in the hypolimnion Johansson et al. Thus, the availability of a bathymetric inventory is a key step in the establishment of a sustainable management plan for most aquatic systems.
In the last decade, the technological capacity for bathymetric mapping has vastly improved. Innovations include the use of differential global positioning systems DGPS in combination with echosounders to effect accurate mapping, and the exportation of the data to geographical information systems GIS. However, these new tools have so far not been applied in most freshwater systems of Brazil.
This can be partially explained not only by the high cost of the equipment, but also by the lack of trained personnel. The equipment and software needed for bathymetric studies Bezerra-Neto, JF. In addition, this new technology must be applied in a scientific context. In Brazil, several lakes have been intensively studied over the past decades. Additionally, this contribution re-evaluated the basic morphometric features and discussed the differences between the new estimates and existing information.
Material and Methods 2. The park has an area of 36, ha, and preserves the largest remaining fragment of the Atlantic Forest in the state Latini and Petreri, According to Matsumura-Tundisi and Tundisiit can be classified as oligotrophic and warm monomictic, with one circulation period usually occurring between May and August. A list of articles and research reports about limnological studies in Lake D. These studies intensified afterthe date of creation of the first postgraduate courses in Ecology and Limnology in Brazil.
Several dissertations and Ph. Dozens of scientific articles, research reports and popular brochures have been published, with this lake as the major study area. This project selected the Rio Doce lakes as the main study area.
A synthesis of this international project was the book edited by Prof. Saijo, published several years ago Tundisi and Saijo, The first bathymetric study of Lake D. In this article, the reader can find a bathymetric chart as well Acta Limnol.
The study was quite innovative for that time, since it used an echo-sounder to obtain the depth data. Three other livrro were also investigated by these authors: The kHz split-beam transducer was positioned vertically, 0.
pdf em inglês – Associação Brasileira de Limnologia
Thus, the data collected by positioning unit was corrected in real time, to provide a horizontal positional accuracy of plus or minus cm. The transducer of the echosounder and the kinematics antenna of the DGPS were set on opposite ends of the same metal tube, with the goal of reducing errors in positioning due to the inclination of the boat.
Survey transects were conducted in a zigzag fashion from one side of the lake to the other, with one transect starting where the previous transect ended.
Single depth measurements were taken where navigation was not possible macrophyte beds or where the maximum depth was less than 1. Database files were created that included latitude, longitude, and depth. Surface interpolation and contour map The spatial data collection of this survey can be considered as sampling values, and to obtain regular grid data for the entire area of the lake, the data must be interpolated. The process of finding data values for unknown locations between observed data locations is known as interpolation.
In this process, the original data collected in the field XYZ file of location and depth are used to generate calculated data points on a regularly spaced grid Awulachew, These interpolation methods were explored to determine the method that provides the best surface estimation.
The program Surfer 8. The next step was to overlay two different geographic information plans maps: The shoreline definition is an important element in the process of creating a bathymetric chart.
This line is made of many points geographic coordinates that assume the value of Z is zero. Since this array of coordinates cannot be produced by an echosounder, we used another approach.
Livro Limnologia, capítulo 8, TUNDISI & TUNDISI, by Fernando Brandão on Prezi
The shoreline points were obtained from calibrated high-precision 1: We used a sub-routine from the software Didger 3. The precision of the calibrated shoreline image was less than 1. Estimating the morphometric parameters The morphometric features were estimated directly from the field data.
The maximum depth was tundiai directly from the field-data matrix. The lake surface Athe bottom area Ba and the lake volume V were estimated from Surfer 8. This program uses three different methods for estimating the lake volume: The volumes of each 4. All points were synchronized to their geographical coordinates with sub-metric precision. This data matrix was processed by the Surfer program, using the Kriging interpolation method. Ljmnologia this procedure, a bathymetric chart with depth curves isobaths every 6 m was generated.
This chart corresponds to the beginning of the dry llmnologia May, when the lake was at its maximum level Figure 1. According to the state park staff members, the lake surface reaches its minimum level, roughly to 1. The lake usually reaches its maximum level just after the rainy season November-March. During our sampling, no depletion was noticeable along the shoreline, and we can assume that the lake was then at its maximum level. The contours of the lake bottom are surprisingly complex.
This pattern is typical in many man-made reservoirs, which suggests that the lake probably originated from damming of an ancient branch of Rio Doce Meis and Tundisi, This large data tundisu generated by the many sampling points made possible a detailed description of the lake basin.
According to Colethe accuracy of every bathymetric chart is directly dependent on the number of sampling points. The new morphometric information differs substantially from previously published values Tables 1 and 2. The estimated total volume They estimated a volume livvro only 8.
We believe limnolobia there must have been a typographical error in their estimates: The estimated lake area ljvro also quite different between the two studies.
We estimated a lake area of 5. Because lake volume and lake area are primary morphometric parameters, these parameters are used in the estimations of all other secondary morphometric features of a lake Cole,von Sperling, Thus, large differences were also noted between the estimations of the secondary morphometric parameters Table 2.
The other lake arms are shallower, with depths of tjndisi to 8 m. These differences are clearer in lateral view Figure 3.
pdf em inglês – Associação Brasileira de Limnologia
This figure also shows that the deepest point is located in the northeastern part Bezerra-Neto, JF. Livdo star indicates the location of maximum depth Depth m 0 4 8 12 16 20 24 28 32 36 40 Figure 3.
Comparison of morphometric data collected in with data collected by Tundisi and Musarra in Parameters This study Volume x m3 The present study also identified several depression zones in the lake. These depressions usually have depths greater than the The same Surfer subroutine was used to calculate the volume of different depth layers of the lake. In this study, each layer was 4 m thick. These estimates made it possible to construct a hypsographic curve depth limnoologia area lines Figure 4.
Conclusions This study used a new procedure that makes it possible to obtain all basic morphometric parameters and to generate a bathymetric chart very rapidly, with sub-metric accuracy.
Additionally, this is a low-cost method, provided the echosounder is available. The most difficult step was tunxisi obtain an affordable cartographic basis, since it is crucial to calibrate the shoreline for this kind of investigation. Considering the differences observed in lake area and volume limnoloiga our and the previous study Table 3we also suggest a revision tyndisi some aspects of lake function, limnlogia as heat content or lake stability and oxygen deficit, that have been published based on the older estimations e.
Thus, there must be large spatial longitudinal differences in properties such as lo- Bezerra-Neto, JF. Percent of total area Percent of max. Therefore, it is also necessary to develop new research efforts aiming to identify the existence of longitudinal horizontal patterns in different limnolobia variables such as chlorophyll a, plankton community and fish assemblage.
This kind of information is certainly essential for the establishment of a truly sustainable management plan for this important lake. Acknowledgements The authors thank Dr. Reid for revising the English style of the manuscript. We also thank the staff of the Parque Estadual do Rio Doce for their collaboration.
Investigation of physical and bathymetric characteristics of Lakes Abaya and Chamo, Ethiopia, and their management implications.