Long‐term shifts in the functional composition and diversity of a tropical dry forest: a 30‐yr study

Abstract:Community-wide seasonal fruiting and seed dispersal by the common brown lemur (Eulemur fulvus fulvus) was investigated in a tropical dry forest, north-western Madagascar. The brown lemur is the sole disperser of large seeds > 10 mm in diameter. Considering the limited assemblage of dispersers, large-seeded plants should display distinctive fruiting patterns to acquire dispersers. To compare fruiting patterns and seed dispersal by the brown lemur between small-seeded and large-seeded plants, fruiting conditions for 432 trees on a transect, feeding activity over 1212 h of observation, and the composition of 1126 dung samples were recorded for 1 y. Seeds of a total of 52 species were identified through both observations and faecal analysis. As rainfall increased, larger numbers of species and individuals of small-seeded plants fruited. Among the 52 species, the brown lemur dispersed 29 and 13 species with small and large seeds, respectively, during the rainy season. High moisture levels probably favoured seed germination and seedling establishment in various species. During the dry season, although small-seeded species rarely fruited, a few large-seeded species, particularly Vitex beraviensis, formed a long-term fruiting peak and provided essential food resources for the brown lemur. Because seeds of these large-seeded plants were frequently dispersed by the brown lemur, dry-season fruiting seemed to be favourable to avoid competition for dispersers with other plant species.

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Coppice shoot dynamics in a tropical dry forest after human disturbance

Journal of Tropical Ecology ◽

10.1017/s0266467410000805 ◽

2011 ◽

Vol 27 (03) ◽

pp. 259-268 ◽

Cited By ~ 8

Author(s):

Mathieu Lévesque ◽

Kurt P. McLaren ◽

Morag A. McDonald

Keyword(s):

Human Disturbance ◽

Tropical Dry Forest ◽

Dry Forest ◽

Average Height ◽

Average Percentage ◽

Regeneration Mechanism ◽

Shoot Dynamics ◽

Rate Of Recovery ◽

Experimental Cutting

Abstract:Coppicing is an important regeneration mechanism in tropical dry forest after disturbance, but little is known about the long-term dynamics and the rate of recovery of the coppice shoots following clearance. This study reports on the growth and dynamics of coppice shoots following experimental cutting in a tropical dry forest in Jamaica. The fate of coppice shoots was tracked on a total of 481 stumps, representing 51 species over 10 y. The number of coppice shoots and the height and dbh of the leading shoots were measured on the tree stumps 14 mo and 10 y after cutting. Coppicing was vigorous for most tree species, but the average number of shoots per stump decreased significantly over the 9 y period, from 25 to 8 shoots per stump. The average height and diameter of the leading shoots after 10 y were 4.5 m and 3.8 cm, respectively, and the average percentage diameter recovered by the shoots varied between 36% and 95% among the species. Coppicing facilitates the long-term persistence of this dry forest, and the rapid growth of coppice shoots contributed to the resilience of most species after cutting.

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Patterns of forest composition and their long term environmental drivers in the tropical dry forest transition zone of southern Africa

Forest Ecosystems ◽

10.1186/s40663-016-0080-9 ◽

2016 ◽

Vol 3 (1) ◽

Cited By ~ 9

Author(s):

Vera De Cauwer ◽

Coert J. Geldenhuys ◽

Raf Aerts ◽

Miya Kabajani ◽

Bart Muys

Keyword(s):

Transition Zone ◽

Southern Africa ◽

Tropical Dry Forest ◽

Dry Forest ◽

Environmental Drivers ◽

Forest Composition ◽

Forest Transition

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Long-term impacts of mid-Holocene drier climatic conditions on Bolivian tropical dry forests

Quaternary Research ◽

10.1017/qua.2019.55 ◽

2019 ◽

Vol 93 ◽

pp. 204-224 ◽

Cited By ~ 1

Author(s):

Heather J. Plumpton ◽

Francis E. Mayle ◽

Bronwen S. Whitney

Keyword(s):

Climate Models ◽

Fire Regime ◽

Tropical Dry Forest ◽

Climatic Conditions ◽

Dry Forest ◽

Tropical Dry Forests ◽

Dry Forests ◽

Seasonally Dry ◽

Threat Status

AbstractThe Bolivian Chiquitano dry forest is the largest block of intact seasonally dry tropical forest in South America and is a priority ecoregion for conservation due to its high threat status. However, the long-term impacts of drier climatic conditions on tropical dry forests are not well understood, despite climate models predicting increased droughts over Bolivia in the coming century. In this paper, we assess the impacts of drier climatic conditions during the mid-Holocene on the Bolivian Chiquitano tropical dry forest using fossilised pollen, phytoliths, macro-charcoal, and geochemical proxies from a sediment core from a large lake (Laguna Mandioré) on the Bolivia–Brazil border. Our results show that drier climatic conditions during the mid-Holocene caused a local-scale, ecotonal expansion of upland savannah at the expense of dry forest. Interaction between drier climatic conditions and fire regime likely exerted a stronger control over the position of the dry forest–savannah ecotone than edaphic factors. However, the majority of the dry forest within the lake catchment maintained a closed canopy throughout the drier conditions of the mid-Holocene, despite floristic turnover towards more drought-tolerant taxa. These findings imply overall resilience of the Chiquitano dry forest biome to future drought, albeit with floristic changes and upland savannah encroachment at ecotones.

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