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BOTANY

The roots of knowledge

Installed a decade ago in its own building at Quinta da Boa Vista, the herbarium survived intact

The older collections of mosses and algae were stored dried and pressed; today the norm is a liquid medium

Diogo Vasconcellos

In her first 13 years as a teacher in the Department of Botany at the National Museum, Andrea Costa changed the herbarium’s location three times. “We needed to transfer the collection from one room to another whenever space was needed for work on the floor or on the roof,” she says. The building had good qualities for the preservation of dehydrated plants, called exsiccatae, namely, open, airy rooms with large windows. But there were frequent leaks. “Since 1995, I’ve always known the palace as a construction site.” In 2008 the department was transferred to a new building in the Botanical Garden, which has kept the collection, the research activities, and the graduate program out of harm’s way.

Founded in 1831, the herbarium at the National Museum is the oldest in the country and one of the most substantial, second only to the Botanical Garden of Rio de Janeiro. There are about 600,000 specimens, 8,000 types (holotypes and paratypes) and various historical collections that were products of expeditions by naturalists. It even contains exsiccatae with the seal of Dom Pedro II or Princess Isabel, both science enthusiasts. In 1872, the young princess participated in an expedition to the mountains of Itatiaia, led by the French botanist Auguste Glaziou (1828–1906—see Pesquisa FAPESP issue no. 231). “He was the Emperor’s landscape gardener,” Costa says, “his projects featured curving designs imitating nature.” And he was responsible for landscaping Quinta da Boa Vista, where the National Museum is located.

Some of the material Glaziou collected was part of an exhibition, which was dismantled and stored securely earlier this year, which is why the fire almost didn’t destroy any botanical material. Almost. “We discovered that ten seeds were on loan to a lab doing CT scans for a three-dimensional study,” says botanist Ruy José Valka Alves, the herbarium’s curator. “One of them was a very rare coconut from the Seychelles islands, obtained through a trade during the nineteenth century.” Besides being a threatened species, it’s worth thousands of dollars on the Chinese alternative medicine market, according to the researcher.

The National Museum’s collections aren’t composed of mere objects: each specimen has a history

Several naturalists who traveled throughout Brazil contributed to the collection, including the German Karl Friedrich Philipp von Martius (1794–1868), who used material deposited in the National Museum in the elaboration of Flora brasiliensis, one of the landmark works on the country’s plant taxonomy. These endeavors usually resulted in collections in which duplicates were deposited in the National Museum and the rest taken to European herbariums. “There were no botanists here, so everything was studied and described over there,” Costa says.

In recent years, by digitizing plant specimens into high definition images the Reflora project seeks to recover the material deposited in foreign herbariums. A part of Glaziou’s collection that is deposited in the National Museum of Natural History in Paris is now in this digital collection. The portion that remained in the National Museum in Brazil has been partly digitized and is about to enter a database that is available for consultation worldwide. It’s one of the projects that extends the reach of a collection which is constantly visited by researchers from all over the world. There is still much work ahead, as only about 20% of the herbarium has been digitized.

The last 40 years represent an important period in the herbarium’s growth, thanks to collections created by postgraduate students in the museum’s botany program, which is currently coordinated by Costa. Today, 30 master’s and 37 doctoral students, guided by 14 professors, study at the building in the Botanical Garden. “We have four fire doors, emergency ladders, and other technologies for protection against fire.”

When a botanist goes into the field, he collects representative branches of native species from the wild, with their flowers and fruit whenever possible. The plant specimens are pressed in newspaper and dried in a chamber for subsequent storage. In the case of the National Museum, they’re stored in plastic boxes fitted into space-saving cabinets, which were obtained thanks to funding from the Vitae Foundation. “Before, we used metal boxes.”

Diogo Vasconcellos Dom Pedro II promoted the collection of plants and mounted exhibitions of exsiccataeDiogo Vasconcellos

“It’s not always possible to identify the samples down to the species level, so some exsiccatae are cataloged using only the name of the genus or family,” Costa explains. This knowledge is refined as researchers conduct further studies on each group and make the identifications more accurate. “There’s a lot of other information linked to each name, such as geographic distribution.” Genetics may also help in the identification process, although it’s not easy to extract DNA from dried plants.

Some plants offer special challenges, such as the bromeliads studied by Costa’s group. They can be very large and difficult to press. An article published this year in the journal Phytotaxa describes a species of bromeliad, Vriesea mourae, found in the Bocaina range in the municipalities of Bananal in São Paulo, and Angra dos Reis, in Rio de Janeiro. Due to its restricted distribution, the plant is already considered threatened. Type-specimens were deposited in several herbaria. “Imagine a palm tree in a herbarium, or a cactus!” Costa says.

One of the problems in maintaining a herbarium is a small beetle, the same species that invades pantries to find flour and cereal. “They really go to town in a botanical collection,” says Costa. That’s why the building smells of mothballs, until recently the only weapon available. A practice that’s easier on the nose is to periodically pass the exsiccatae through a greenhouse at 70° C, killing both larvae and adults, which is done every time a specimen comes into the collection or returns from being on loan for study.

Results of exploration
“This has always been an institution which made grand botanical expeditions,” Costa notes. One example was the BR-364 highway in the Amazon, in the 1960s. “As they opened the road, researchers from the National Museum were collecting specimens.” The result was a huge collection for the herbarium. There is also the material gathered by the Italian-Brazilian ethnologist Adolpho Ducke (1876–1959), which is shared with the Emílio Goeldi Museum of Pará and greatly enriched the National Museum’s diversity of Amazonian plants.

Diogo Vasconcellos The herbarium stores its samples protected in plastic boxesDiogo Vasconcellos

Costa also highlights the work of ecologist Fernando Segadas-Vianna, a specialist in the ecology of coastal vegetation, called the restinga. A researcher at the National Museum until his death in the mid-1990s, Vianna left an archetypal collection. “It’s possible to reconstruct a flora that no longer exists, like the Copacabana restinga.” Today, in this neighborhood that has been completely overbuilt and widened by dredging, with its beach and adjacent promenade frequented by teeming crowds, there are no traces of the vegetation that once grew on its sands. Between 1965 and 1979, Vianna led the 23-volume production titled Ecological Flora of the Restinga of Southestern Brazil (Flora ecológica das restingas do Sudeste do Brasil).

Last year, Ruy José Valka Alves spent 15 days driving 6,000 kilometers through the state of Tocantins. He found seven new species, six of which have already had their descriptions submitted for publication. But he doesn’t work with dehydrated foliage exclusively. The museum’s Botany Department also has a collection of pollen in microscopy slides, a xylotheque (collection of wood specimens), and algae, fungi, and lichens preserved in a liquid medium.

Alves is a specialist in high-altitude plants and the flora of the island of Trindade. Part of a volcanic archipelago 1,200 kilometers off the coast of Espírito Santo State, Trindade saw its first expedition from the National Museum just over a century ago in 1916. In an article published this year in the IAWA Journal, he and his colleagues presented their analysis of wood from a mysteriously dead forest. “Seventeenth-century travelers described a forest, eighteenth-century visitors spoke of standing dead trees, and nineteenth-century travelers saw them already fallen.” Analyzing the wood, it was possible to conclude that there were at least two species, not just one as had been previously thought. Alves also set up wide-mouth bottles with a liquid inside to capture and preserve pollen grains and found—in partnership with a palynologist from the Federal University of Rio Grande do Sul, and other colleagues—that these small particles travel on atmospheric currents. They are able to arrive on the island from the Americas, as reported in another 2018 article, in the Brazilian Journal of Botany. “We even found bat hair, and there aren’t any bats in the archipelago.”

Alves is an enthusiast of climbing mountains and trailblazing into unknown places, whose stories show that the collections in the National Museum aren’t composed of mere objects. “Every specimen represents blood given by a researcher who has climbed a mountain. They lost not merely things, every one of them had a story.”

Jardim Botânico Fountain of the Muses in the Botanical GardenJardim Botânico

Beyond the garden

Visited by about 650,000 people a year, the arboretum—an area with about 2,500 species from around the world, including plant collections, lakes with giant Amazonian water lilies, and greenhouses with orchids and bromeliads—is the most visible and well-known part of the Botanical Garden of Rio (JBRJ). It is one of the oldest scientific institutions in the country, created in June 1808. Inside the buildings surrounding the arboretum, the JBRJ houses the herbarium, with collections of nuts, wood samples, and about 850,000 dehydrated plants that serve as reference specimens for botany research.

There are 42 researchers working there. One of the projects in progress is the Reflora Virtual Herbarium, which currently includes 3.2 million images and descriptions of native plants (see Pesquisa FAPESP issue nos. 229 and 241). Another project is Jabot, a management system for scientific herbarium collections, which was released for use by other institutions in 2016 and is currently in use at herbariums in 42 universities and research centers across Brazil (see Pesquisa FAPESP issue no. 263).

The library, created in 1890 beginning with the works of Dom Pedro II, currently has 43,000 volumes, including 1,680 rare works. The JBRJ offers master’s and doctoral programs at the National School of Tropical Botany (ENBT), which currently has about 70 students. Like other institutions, it emphasizes the search for partnerships with state-owned or private corporations in order to increase and complement its research funds (see article on page 26).

Carlos Fioravanti

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