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Algae at depth

Project completes four decades of mapping the species in São Paulo

After four decades of research and more than 40,000 kilometers of walking to collect material from the sea, rivers, lakes, and dams, the biologist Carlos Bicudo is close to completing the mapping of the algae in São Paulo state. This thematic project began to become a reality in July last year, with the start of the thematic project Phycologic Flora of the State of São Paulo, financed by FAPESP, coordinated by Bicudo, and in which 42 researchers from 27 centers in Brazil and abroad are taking part.

This projects for identifying all the phycologic flora (algae) in São Paulo, is part of the Biota-FAPESP program for surveying the biological resources in the State and is unprecedented in Brazil. It will help in the accurate monitoring of the water quality of the water sources, besides providing indicators for the conservation or the recovery of aquatic environments. It is a project if taxonomy, the science of identifying and classifying species. “Just as you cannot read without knowing the alphabet, you cannot do science without taxonomy”, emphasizes Bicudo, a 63 year-old biologist.

Unknown past
This work also helps pinpoint what no long exists: all around the world species of flora and fauna become extinct, and very often, we do not even know that these organisms existed before. The State of São Paulo was once entirely covered by forests, and nowadays, they cover only 10% of the area. No one knows, for example, what used to exist in the Tietê River.

Bicudo already had this in mind when he went to work for the Botanical Institute (nowadays linked to the Environmental Department) in 1960, when still a student. Then, he began to organize a herbarium with his colleagues Rosa Maria Teixeira Bicudo, Marilza Cordeiro Marino and Noemy Yamagushi Tomita. Today the herbarium has 15,000 examples of dried marine algae stretched out on paper and another 3,000 freshwater specimens preserved in jars.

At the beginning, nonetheless, almost everything was still to be done. The first 200 algae that went into the institute’s herbarium, for example, were duplicates already identified in the 19th century by foreign naturalists, such as Von Martius (see table). They were itemized at the archives of the old Geographical and Geological Commission of the State of São Paulo (the present-day Geological Institute of the Environment Department).

All the rest was collected over the last 40 years by the researchers and trainees of the Botanical Institute. It has been calculated, however, that the 2,642 species of algae already grouped represent only half of those existing in nature. By assembling more material in 400 São Paulo towns, the total number of species ought to climb to 5,000. Bicudo reveals that since the beginning of the project around 500 undocumented species have been found of which some 40 are unknown anywhere in the world. Since the beginning of the 60s, Bicudo and his group have carried out research throughout the State and assembled the 3,000 samples of freshwater algae in the herbarium.

Gaps at sea
But there were gaps: “An analysis of the 47 publications dedicated to the taxonomy of the macroscopic, bentonitic marine algae of the State of São Paulo, for example, showed that this flora is represented by 308 species, of which 198 are Rhodophyceae, 68 Chlorophyceae and 42 Phaeophyceae”.

Information was lacking on this flora because the deeper area called the infra-coastal zone, only accessible by diving, had not been surveyed. In the case of the blue marine algae (Cyanophyceae) of the supra-coastal band, in shallower waters, the literature only listed 108 species, since the area cover was quite small.

Up to the beginning of the project, 2,226 freshwater species had been identified, in other words, around 40% of all those existing. Over the last 40 years, many aquatic environments have vanished and there has been a tendency to seek much more material in still (lakes, lagoons, marshes) and semi-still environments (reservoirs, dams) than in moving waters (rivers, streams and creeks).

Besides the their importance of preserving ecosystems, since they form the first link in the food chain in lakes, dams, rivers and the sea, the algae indicate the quality of the water. The Charophyceae, for example, inhabit excellent fishing spots. The Cyanophyceae and the Euglenoplyceae, on the other hand, indicate environments rich in phosphorus – that is to say, polluted by sewage – while the Bacillariophyceae or diatomaceous algae do not tolerate these environments and their presence is a sign of water in good condition.

It was based on algae that the pollution of the Garças Lake, in the São Paulo Botanical Garden, by sewage was detected; “We are studying the material and the physical and chemical condition of the lake in order, then, to establish a project to recover it”.

By the end of the project, the number of freshwater species known in the State could easily double. The Zygnemaphyceae, for example, should rise from 1,053 to 1,500 or 1,600 and the 61 Bacillariophyceae should come to 900.

To achieve this, the collecting was stepped up. Up to August, 18 of the 50 planned trips were carried out. The group studying freshwater species, with four researchers and six students, made 15 trips to the interior of the State and collected material from running water, little represented in the herbarium. The marine algae group, with four researchers from the institute, three professors from USP and five students, made three research expeditions to the north coast: as they already had many good quality specimens from the area between the low and high tide, the gathering began being done in the deeper waters of the infra-costal band – below low tide – and from the islands.

The researchers traveled equipped with nets, penknives, jars, and a fixing solution to preserve the material. They also take with them three pieces of equipment: a satellite GPS location device, a PH meter (acidity or alkalinity), and another for measuring the conductivity of the water (indicating the number of ions present). Low conductivity, for example, is a sign of good quality water, while high conductivity indicates polluted water.

Most of the bigger rivers in São Paulo have already been surveyed – Grande, Paraná, Tietê, Paranapanema and Turvo –, so have the dams. The size of the specimens varies from 0.002 millimeters (the case of the Diogenes genus of algae in still freshwater) to 2 meters (the freshwater characeaes) and even 35 meters in length (the marine, deepwater Macrocystis).

The 43 Brazilian and foreign researchers involved analyze the material. Some of the foreign researchers work here, others receive the material in their own countries. Bicudo reveals that they had to turn to specialists in the Czech Republic, Japan, the United States, Australia, and Argentina to identify and classify some freshwater species.

When writing his doctoral thesis in 1969, Bicudo needed a new collection from some parts of the city of São Paulo. In the Chá field, nowadays the Anhangabaú Valley , species would grow that could not be collected again, since the Anhangabaú stream had already been canalled over. “We even have samples of diatomaceous algae collected on the Paulista Avenue at the end of the 19th century, and they no longer exist”.

The researcher says that the work of Professor Aylthon Brandão Joly on algae in bay of Santos is a landmark in the study of algae in the state: “He identified 100 species of algae that occurred there, and today, undoubtedly, there are no more than 50 of them left. The place has grown, the environment has been effected, and we have lost diversity, we have lost species”.

Thirteen volumes
Bicudo says that even in the United States, a country that invests US$ 1.5 million a year in training taxonomists, no project similar to the one in São Paulo has ever been taken on. Here we are mapping where every species occurs. Some occur throughout the state, others only in certain regions.

As well as environmental conservation and recovery, the project aims to train human resources: 70 people from Brazil and neighboring countries have been through the Phycology Section of the Botanical Institute, to survey freshwater and marine algae.

The project will publish the Phycological Flora of the State of São Paulo, a 13-volume set giving the description of all the surveys carried out from the 19th century to the year 2000. The first volume is ready for publication and refers to the 31 species of Carofaceae algae that occur in the State. Manuals for identifying algae to use in high schools and colleges throughout Brazil, will also be published.

Since Von Martius

Foreign naturalists in the 19th century were the first to identify Brazilian algae. Prominent among these was the Bavarian Carl Friedrich Philip von Martius (1794-1868), a member of the scientific mission that surveyed this country between 1817 and 1820. Von Martius collected and listed 80 species of algae in the classic book Flora Brasiliensis, of 1833.

Other 19th century foreigners identified Brazilian algae, generally on the basis of samples sent to them in their own countries. After this, almost nothing was done until the mid 20th century.

In 1960, Carlos Bicudo and his colleagues Rosa Maria Bicudo, Marilza Marino and Noemy Tomita collected the first marine species in São Vicente bay and the Ubatuba region. At the time, they were taking the Natural History course (the origin of the present Biosciences Institute) at the then Philosophy, Science, and Arts Faculty of the University of São Paulo USP). And they had classes in the taxonomy of marine algae with Professor Aylthon Brandão Joly, considered the creator of Brazilian phycology.

In 1957, Joly published the Contribution to the Knowledge of the Marine Phycological Flora of the Bay of Santos and Surroundings, the first planned inventory of algae in a particular region of Brazil. Based on the material collected by his group, in 1965, Joly would also publish the important study Marine Flora of the North Coast of the State of São Paulo and Neighboring Regions.

In 1961 and 1962, Bicudo and Rosa Maria undertook the first freshwater collections in the Biological Reserve of the State Park of the Springs of the Ipiranga and later published two fascicles on the subject. Between 1963 and 1965, Bicudo did his residency and master’s degree at the University of Michigan (USA), under the guidance of Gerald W. Prescott. He returned to this country with ten boxes of photocopies of everything that had been published on Brazilian algae in the United States and began assembling freshwater material in the state. From then on, he developed the study that culminated in the ambitious present mapping project.

Phycological Flora of the State of São Paulo
Thematic Project
Carlos Eduardo de Mattos Bicudo – Botanical Institute
R$ 87,750 and US$ 83,786