Canopy and litter ant assemblages share similar climate–species density relationships

Tropical forest canopies house most of the globe's diversity, yet little is known about global patterns and drivers of canopy diversity. Here, we present models of ant species density, using climate, abundance and habitat (i.e. canopy versus litter) as predictors. Ant species density is positively associated with temperature and precipitation, and negatively (or non-significantly) associated with two metrics of seasonality, precipitation seasonality and temperature range. Ant species density was significantly higher in canopy samples, but this difference disappeared once abundance was considered. Thus, apparent differences in species density between canopy and litter samples are probably owing to differences in abundance–diversity relationships, and not differences in climate–diversity relationships. Thus, it appears that canopy and litter ant assemblages share a common abundance–diversity relationship influenced by similar but not identical climatic drivers.

Download Full-text

Global patterns and climatic controls of forest structural complexity

Nature Communications ◽

10.1038/s41467-020-20767-z ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Martin Ehbrecht ◽

Dominik Seidel ◽

Peter Annighöfer ◽

Holger Kreft ◽

Michael Köhler ◽

...

Keyword(s):

Forest Structure ◽

Laser Scanning ◽

Structural Complexity ◽

Terrestrial Laser Scanning ◽

Ecosystem Functions ◽

The Earth ◽

Precipitation Seasonality ◽

Latitudinal Patterns ◽

Global Patterns ◽

Primary Forests

AbstractThe complexity of forest structures plays a crucial role in regulating forest ecosystem functions and strongly influences biodiversity. Yet, knowledge of the global patterns and determinants of forest structural complexity remains scarce. Using a stand structural complexity index based on terrestrial laser scanning, we quantify the structural complexity of boreal, temperate, subtropical and tropical primary forests. We find that the global variation of forest structural complexity is largely explained by annual precipitation and precipitation seasonality (R² = 0.89). Using the structural complexity of primary forests as benchmark, we model the potential structural complexity across biomes and present a global map of the potential structural complexity of the earth´s forest ecoregions. Our analyses reveal distinct latitudinal patterns of forest structure and show that hotspots of high structural complexity coincide with hotspots of plant diversity. Considering the mechanistic underpinnings of forest structural complexity, our results suggest spatially contrasting changes of forest structure with climate change within and across biomes.

Download Full-text

Sensitivities of glacier mass balance and runoff to climate perturbations in Norway

Annals of Glaciology ◽

10.3189/2015aog70a004 ◽

2015 ◽

Vol 56 (70) ◽

pp. 79-88 ◽

Cited By ~ 16

Author(s):

Markus Engelhardt ◽

Thomas V. Schuler ◽

Liss M. Andreassen

Keyword(s):

Mass Balance ◽

Temperature Change ◽

Air Temperature ◽

Annual Runoff ◽

Precipitation Change ◽

Glacier Mass Balance ◽

Northern Norway ◽

Temperature Range ◽

Temperature And Precipitation ◽

Southern Norway

AbstractThis study evaluates sensitivities of glacier mass balance and runoff to both annual and monthly perturbations in air temperature and precipitation at four highly glacierized catchments: Engabreen in northern Norway and Ålfotbreen, Nigardsbreen and Storbreen, which are aligned along a west–east profile in southern Norway. The glacier mass-balance sensitivities to changes in annual air temperature range from 1.74 m w.e. K−1 for Ålfotbreen to 0.55 m w.e. K−1 for Storbreen, the most maritime and the most continental glaciers in this study, respectively. The runoff sensitivities of all catchments are 20–25% per degree temperature change and 6–18% for a 30% precipitation change. A seasonality of the sensitivities becomes apparent. With increasing continentality, the sensitivity of mass balance and runoff to temperature perturbations during summer increases, and the sensitivity of annual runoff to both temperature and precipitation perturbations is constricted towards changes during the ablation period. Comparing sensitivities in northern and southern Norway, as well as the variability across southern Norway, reveals that continentality influences sensitivities more than latitude does.

Download Full-text

Effects of the Trophobiont HerbivoreCalloconophora pugionata(Hemiptera) on Ant Fauna Associated withMyrcia obovata(Myrtaceae) in a Montane Tropical Forest

Psyche A Journal of Entomology ◽

10.1155/2012/783945 ◽

2012 ◽

Vol 2012 ◽

pp. 1-8 ◽

Cited By ~ 7

Author(s):

Roberth Fagundes ◽

Kleber Del-Claro ◽

Sérvio Pontes Ribeiro

Keyword(s):

Species Richness ◽

Species Diversity ◽

Tropical Forest ◽

Host Plant ◽

Atlantic Forest ◽

Main Hypothesis ◽

Ant Assemblages ◽

Montane Tropical Forest ◽

Positive Effect ◽

Dominant Ant

Many studies have investigated the mechanisms behind the structure of arboreal ant assemblages. In this study, the objective was to evaluate the effect of availability of honeydew-producing colonies ofCalloconophora pugionata(Membracidae) on the structure of ant assemblages associated with the host plantMyrcia obovata(Myrtaceae) in an Atlantic forest of Minas Gerais (Brazil). Our experiment consisted in a gradual exclusion of hemipteran colonies out of the host plant crown and further record of the ant assemblage response (species richness, composition, and occurrence) to the presence and density of treehopper colonies. The hypothesis was that an increase in the number of trophobiont herbivores results in an increase in tending ant occurrence but a reduction in ant species diversity. Results corroborated our main hypothesis: membracids had a positive effect on the occurrence of ants but negative on species richness. Overall insect occurrence was also reduced with increasing inC. pugionatacolonies, probably due to strengthening dominant ant species territory sizes and intensification of patrolling.

Download Full-text

Analysis of ant assemblages of a monsoon tropical forest based on isotopic metrics

10.47640/1605-7678_2015_86_2_41 ◽

2015 ◽

Author(s):

V.A. Zryanin

Keyword(s):

Tropical Forest ◽

Ant Assemblages

Download Full-text

Reconstruction of the annual mass balance of Chhota Shigri glacier, Western Himalaya, India, since 1969

Annals of Glaciology ◽

10.3189/2014aog66a104 ◽

2014 ◽

Vol 55 (66) ◽

pp. 69-80 ◽

Cited By ~ 77

Author(s):

Mohd Farooq Azam ◽

Patrick Wagnon ◽

Christian Vincent ◽

Alagappan Ramanathan ◽

Anurag Linda ◽

...

Keyword(s):

Mass Balance ◽

Western Himalaya ◽

Winter Precipitation ◽

Temperature Index ◽

Temperature And Precipitation ◽

Chhota Shigri Glacier ◽

Decadal Scale ◽

Climatic Drivers ◽

Precipitation Records ◽

Significant Mass Loss

AbstractThis study presents a reconstruction of the mass balance (MB) of Chhota Shigri glacier, Western Himalaya, India, and discusses the regional climatic drivers responsible for its evolution since 1969. The MB is reconstructed by a temperature-index and an accumulation model using daily air-temperature and precipitation records from the nearest meteorological station, at Bhuntar Observatory. The only adjusted parameter is the altitudinal precipitation gradient. The model is calibrated against 10 years of annual altitudinal MB measurements between 2002 and 2012 and decadal cumulative MBs between 1988 and 2010. Three periods were distinguished in the MB series. Periods I (1969-85) and III (2001-12) show significant mass loss at MB rates of -0.36±0.36 and -0.57±0.36mw.e.a-1 respectively, whereas period II (1986-2000) exhibits steady-state conditions with average MBs of -0.01 ±0.36mw.e.a–1. The comparison among these three periods suggests that winter precipitation and summer temperature are almost equally important drivers controlling the MB pattern of Chhota Shigri glacier at decadal scale. The sensitivity of the modelled glacier-wide MB to temperature is -0.52 m w.e. a–1 °C–1 whereas the sensitivity to precipitation is calculated as 0.16mw.e.a-1 for a 10% change.

Download Full-text