Distribution and conservation of Cactaceae in Brazilian Seasonally Dry Tropical Forests: insights from floristic and phytosociological surveys

Species lists available from floristic and phytosociological studies contain important information about species distributions that are useful for making biogeographical inferences and even to evaluate conservation status of species and ecosystems. In the case of the Caatinga, this information may contribute to challenging the pre-established idea that it is a homogeneous vegetation unit. The strong relation between the substrate and the plant assemblages of the Caatinga may characterise different types of vegetation. In this way, the objective of the present study is to evaluate whether differences in the distribution of Cactaceae relate to distinctive types of substrate (sedimentary and crystalline) as much in terms of floristic richness as species density. Concomitantly, we evaluated the conservation status of the Caatinga areas studied. To obtain the data, we undertook a bibliographic revision of floristic and phytosociological studies in the Caatinga and constructed a similarity matrix using the selected floristic studies in order to evaluate the relation among different areas of Caatinga. We found that 48 areas included Cactaceae species; 33 species distributed in 14 genera were recorded. Among these taxa, Cereus jamacaru was the species that presented the largest number of occurrences, appearing in 17 areas, followed by Pilosocereus gounellei (=Xiquexique gounellei), found in 11 studies, and Tacinga inamoena in 10. The grouping analysis resulted in the formation of 10 groups, with a remarkable relationship between species and soil type. There were differences in both the diversity and density of species related with the degree of conservation of the Caatinga, noticeable from the direct relationship between conservation and richness and, indirectly, between density and number of species.

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Two new species of Jatropha (Euphorbiaceae) from limestone outcrops in Brazilian seasonally dry tropical forests

Phytotaxa ◽

10.11646/phytotaxa.451.1.6 ◽

2020 ◽

Vol 451 (1) ◽

pp. 73-82

Author(s):

ARIANE DOS SANTOS MOREIRA ◽

JOSÉ FLORENCIO CERQUEIRA OLIVEIRA ◽

INÊS CORDEIRO ◽

DANIELA SANTOS CARNEIRO TORRES

Keyword(s):

New Species ◽

Tropical Forests ◽

Related Species ◽

Conservation Status ◽

Distribution Map ◽

Closely Related Species ◽

Seasonally Dry ◽

Seasonally Dry Tropical Forests ◽

Two New Species ◽

Dry Tropical Forests

We describe and illustrate two new species of Jatropha from Bahia State, Brazil: Jatropha longibracteata and Jatropha paganuccii. The two new species occur on limestone outcrops in seasonally dry tropical forests. We also provide a distribution map and IUCN conservation status, as well as morphological comparisons with the closely related species J. calcarea, J. martiusii, and J. palmatipartita.

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El Niño-Southern Oscillation affects the water relations of tree species in the Yucatan Peninsula, Mexico

Scientific Reports ◽

10.1038/s41598-021-89835-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jorge Palomo-Kumul ◽

Mirna Valdez-Hernández ◽

Gerald A. Islebe ◽

Manuel J. Cach-Pérez ◽

José Luis Andrade

Keyword(s):

Water Potential ◽

Leaf Area ◽

Tropical Forests ◽

Specific Leaf Area ◽

Tree Species ◽

Deciduous Species ◽

Mature Trees ◽

Seasonally Dry ◽

Seasonally Dry Tropical Forests ◽

Dry Tropical Forests

AbstractWe evaluated the effect of ENSO 2015/16 on the water relations of eight tree species in seasonally dry tropical forests of the Yucatan Peninsula, Mexico. The functional traits: wood density, relative water content in wood, xylem water potential and specific leaf area were recorded during the rainy season and compared in three consecutive years: 2015 (pre-ENSO conditions), 2016 (ENSO conditions) and 2017 (post-ENSO conditions). We analyzed tree size on the capacity to respond to water deficit, considering young and mature trees, and if this response is distinctive in species with different leaf patterns in seasonally dry tropical forests distributed along a precipitation gradient (700–1200 mm year−1). These traits showed a strong decrease in all species in response to water stress in 2016, mainly in the driest site. Deciduous species had lower wood density, higher predawn water potential and higher specific leaf area than evergreen species. In all cases, mature trees were more tolerant to drought. In the driest site, there was a significant reduction in water status, regardless of their leaf phenology, indicating that seasonally dry tropical forests are highly vulnerable to ENSO. Vulnerability of deciduous species is intensified in the driest areas and in the youngest trees.

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S. H. Bullock, H. A. Mooney & E. Medina (eds) 1995. Seasonally dry tropical forests. Cambridge University Press, xvii + 450pp. Hardback. ISBN 0 521 43514 5. Price £65.00.

Journal of Tropical Ecology ◽

10.1017/s0266467400010361 ◽

1997 ◽

Vol 13 (1) ◽

pp. 161-162 ◽

Cited By ~ 1

Author(s):

M. D. Swaine

Keyword(s):

Tropical Forests ◽

Cambridge University ◽

Seasonally Dry ◽

Seasonally Dry Tropical Forests ◽

Dry Tropical Forests

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Taxonomic revision of Amorimia W.R. Anderson (Malpighiaceae)

Hoehnea ◽

10.1590/2236-8906-47/2017 ◽

2018 ◽

Vol 45 (2) ◽

pp. 238-306 ◽

Cited By ~ 1

Author(s):

Rafael Felipe de Almeida

Keyword(s):

South America ◽

Tropical Forests ◽

Taxonomic Revision ◽

Identification Key ◽

Risk Assessments ◽

Distribution Maps ◽

Seasonally Dry ◽

Seasonally Dry Tropical Forests ◽

Dry Tropical Forests

ABSTRACT The taxonomic revision of Amorimia (Malpighiaceae) is presented, including typifications, and descriptions for all accepted species. The genus is endemic to Seasonally Dry Tropical Forests and Rainforests of South America, and its species can be distinguished by morphological details of leaves, indumenta, inflorescences, flowers, and fruits. This study includes an identification key for the subgenera and species of Amorimia, illustrations, distribution maps, conservation risk assessments, and comments on ecology, nomenclature, and taxonomy for all species. Additionally, I provide a key to differentiate Amorimia from the remaining genera of the Malpighioid clade.

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Tropical Forests Natural History, Diversity, and Potentiality as Theatres of Human Adaptation and Negotiation

Tropical Forests in Prehistory, History, and Modernity ◽

10.1093/oso/9780198818496.003.0006 ◽

2019 ◽

Author(s):

Patrick Roberts

Keyword(s):

Tropical Forest ◽

Tropical Forests ◽

Homo Sapiens ◽

Terrestrial Ecosystems ◽

Black Pepper ◽

Wood Products ◽

Tropical Rainforests ◽

Cultural Significance ◽

Seasonally Dry ◽

Dry Tropical Forests

The above quote by the German poet, novelist, and painter Herman Hesse highlights the cultural significance of forests in nineteenth- and twentieth-century western culture as the ‘natural’ contrast to growing urban populations and industrial expansion. Hesse’s focus on the ‘ancient’ element of these environments is certainly valid in a tropical context, given that tropical forests are some of the oldest land-based environments on the planet, existing for over one thousand times longer than Homo sapiens (Upchurch and Wolf, 1987; Davis et al., 2005; Ghazoul and Shiel, 2010; Couvreur et al., 2011). This antiquity also makes them one of the richest and most diverse terrestrial ecosystems on the planet (Whitmore, 1998; Ghazoul and Shiel, 2010). Tropical rainforests, for example, contain over half of the world’s existing plant, animal, and insect species (Wilson, 1988). A significant portion of the developed world’s diet today originated in tropical forests—including staples such as squash and yams, spices such as black pepper, cinnamon, cloves, and sugar cane, and fruits including bananas, coconuts, avocados, mangoes, and tomatoes (Iriarte et al., 2007; Roberts et al., 2017a). Tropical forests also often provide ample freshwater for their inhabitants. However, despite popular perceptions of forests, and specifically tropical forests, as uniform, they are, in fact, highly variable across space and time. In tropical evergreen rainforests productivity is often primarily allocated to wood products, meaning that edible plants and animals for human subsistence have been considered lacking, or at least more difficult to extract, relative to more open tropical forest formations (Whitmore, 1998; Ghazoul and Shiel, 2010). Similarly, while evergreen tropical rainforests generally receive significant precipitation and freshwater, seasonally dry tropical forests are subject to sub-annual periods of aridity. Therefore, while archaeologists and anthropologists have tended to see ‘tropical forest’ as a uniform environmental block, it is important to explore the diversity within this category.

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