Blurred lines between competition and parasitism

Stewart, Tara E.; Schnitzer, Stefan A.

doi:10.1111/btp.12444

Cited by 25 publications

(22 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Lianas and trees have coexisted in tropical forests for millions of years and the ability to climb was an early innovation in terrestrial plants (Burnham ). However, the factors that determine the relative abundance of lianas and trees, and whether liana and tree densities are inherently stable, is the subject of recent investigation (Stewart and Schnitzer , Muller‐Landau and Visser , Visser et al. 2018a , b).…”

Section: Discussionmentioning

confidence: 99%

“…Lianas and trees have coexisted in tropical forests for millions of years and the ability to climb was an early innovation in terrestrial plants (Burnham 2015). However, the factors that determine the relative abundance of lianas and trees, and whether liana and tree densities are inherently stable, is the subject of recent investigation (Stewart and Schnitzer 2017, Muller-Landau and Visser 2018, Visser et al 2018a. One potential explanation is that liana and tree fitness and demographic rates are controlled by factors other than liana-tree competition, and thus a modest change in the abundance of one group does not necessarily reduce the abundance of the other.…”

Section: Does Seasonal Water Partitioning Explain Liana and Tree Coexmentioning

confidence: 99%

See 1 more Smart Citation

Lianas have a seasonal growth advantage over co‐occurring trees

Schnitzer

Heijden

2019

Ecology

Self Cite

View full text Add to dashboard Cite

The seasonal growth advantage hypothesis posits that plant species that grow well during seasonal drought will increase in abundance in forests with increasing seasonality of rainfall both in absolute numbers and also relative to co‐occurring plant species that grow poorly during seasonal drought. That is, seasonal drought will give some plant species a growth advantage that they lack in aseasonal forests, thus allowing them attain higher abundance. For tropical forest plants, the seasonal growth advantage hypothesis may explain the distribution of drought‐adapted species across large‐scale gradients of rainfall and seasonality. We tested the seasonal growth advantage hypothesis with lianas and trees in a seasonal tropical forest in central Panama. We measured the dry‐season and wet‐season diameter growth of 1,117 canopy trees and 648 canopy lianas from 2011 to 2016. We also evaluated how lianas and trees responded to the 2015–2016 El Niño, which was the third strongest el Niño drought on record in Panama. We found that liana growth rate was considerably higher during the dry‐season months than the wet‐season months in each of the five years. Lianas achieved one‐half of their annual growth during the 4‐month dry season. By contrast, trees grew far more during the wet season; they realized only one‐quarter of their annual growth during the dry season. During the strong 2015–2016 El Niño dry season, trees essentially stopped growing, whereas lianas grew unimpeded and as well as during any of the previous four dry seasons. Our findings support the hypothesis that seasonal growth gives lianas a decided growth advantage over trees in seasonal forests compared to aseasonal forests, and may explain why lianas peak in both absolute and relative abundance in highly seasonal tropical forests. Furthermore, the ability of lianas to grow during a strong el Niño drought suggests that lianas will benefit from the predicted increasing drought severity, whereas trees will suffer, and thus lianas are predicted to increase in relative abundance in seasonal tropical forests.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Does Seasonal Water Partitioning Explain Liana and Tree Coexmentioning

confidence: 99%

Lianas have a seasonal growth advantage over co‐occurring trees

Schnitzer

Heijden

2019

Ecology

Self Cite

View full text Add to dashboard Cite

show abstract

“…Lianas subsequently affect recovery of forest diversity, biomass, carbon uptake, structure, and function (Box 1). However, liana-tree interactions are highly variable and empirical evidence is often lacking to distinguish parasitism from resource-based competition (Stewart and Schnitzer, 2017). Some of the reported negative impacts of lianas on trees may be confounded by abiotic conditions favouring lianas that also covary with disturbance, e.g., high temperatures, humidity and exposure to wind (Magnago et al, 2017).…”

Section: Variation In Liana Ecology-parasites Parasitoids and Bandagesmentioning

confidence: 99%

Conceptualising the Global Forest Response to Liana Proliferation

Marshall

Platts

Chazdon

et al. 2020

Front. For. Glob. Change

View full text Add to dashboard Cite

Lianas are woody vines, rooted in the soil, and supported physically by trees. Lianas contribute to forest ecosystem functioning globally, but especially in the tropics and subtropics. However, prolific liana growth following heavy disturbance frequently affects subsequent recovery of forest tree diversity, biomass, structure, and function. Understanding this forest liana dynamic, and its sensitivity to climate and anthropogenic forces, is essential for worldwide forest restoration and climate change mitigation. Here, we synthesise the evidence for both positive and negative effects of lianas on forests and propose a framework that outlines the expected global response of forests to disturbance-induced liana proliferation. Emerging evidence suggests that lianas play a major role in both facilitating and delaying forest recovery following disturbance. At low levels of disturbance and/or where environmental conditions favour tree growth, lianas can facilitate forest recovery by protecting trees from extreme weather, fire, weed invasion and herbivory. However, under conditions where lianas proliferate beyond critical thresholds, positive feedbacks are expected to induce and sustain liana-dominated forest states that can endure for decades or even longer. We conceptualise alternative classes of forest recovery response to disturbance and describe measurement and modelling of liana thresholds. We identify four essential challenges for global change science relating to lianas: (1) incorporation of lianas and sapling stems into forest monitoring and tree stand measurements worldwide; (2) long-term experiments to determine variation in liana-tree competition, and potential drivers across forest successional gradients; (3) identification and prediction of liana thresholds and other alternative forest recovery response classes; and (4) dynamic mechanistic modelling of forest recovery to determine regional and global variation within and among different recovery response classes, in relation to variation in potential drivers, liana feedbacks and their interactions. Addressing these challenges will determine the importance of lianas in shaping regional and global forest composition, recovery and dynamics.

show abstract

“…In comparison to previous efforts of including new PFTs into the ED2 (Ise & Moorcroft, 2010;Wang, LeBauer, & Dietze, 2013), the incorporation of lianas entails the additional complexity of representing the parasitic relationship with infested trees: lianas, in that sense, are unique because they climb host trees and invade the same spatial location (Stewart & Schnitzer, 2017). From a modeling point of view, this means that some cohorts (attached lianas and their hosts) can no longer be considered independent from one another.…”

Section: Model Developmentmentioning

confidence: 99%

Modeling the impact of liana infestation on the demography and carbon cycle of tropical forests

Brugnera

Meunier

Longo

et al. 2019

Global Change Biology

Self Cite

View full text Add to dashboard Cite

There is mounting empirical evidence that lianas affect the carbon cycle of tropical forests. However, no single vegetation model takes into account this growth form, although such efforts could greatly improve the predictions of carbon dynamics in tropical forests. In this study, we incorporated a novel mechanistic representation of lianas in a dynamic global vegetation model (the Ecosystem Demography Model). We developed a liana‐specific plant functional type and mechanisms representing liana–tree interactions (such as light competition, liana‐specific allometries, and attachment to host trees) and parameterized them according to a comprehensive literature meta‐analysis. We tested the model for an old‐growth forest (Paracou, French Guiana) and a secondary forest (Gigante Peninsula, Panama). The resulting model simulations captured many features of the two forests characterized by different levels of liana infestation as revealed by a systematic comparison of the model outputs with empirical data, including local census data from forest inventories, eddy flux tower data, and terrestrial laser scanner‐derived forest vertical structure. The inclusion of lianas in the simulations reduced the secondary forest net productivity by up to 0.46 tC ha−1 year−1, which corresponds to a limited relative reduction of 2.6% in comparison with a reference simulation without lianas. However, this resulted in significantly reduced accumulated above‐ground biomass after 70 years of regrowth by up to 20 tC/ha (19% of the reference simulation). Ultimately, the simulated negative impact of lianas on the total biomass was almost completely cancelled out when the forest reached an old‐growth successional stage. Our findings suggest that lianas negatively influence the forest potential carbon sink strength, especially for young, disturbed, liana‐rich sites. In light of the critical role that lianas play in the profound changes currently experienced by tropical forests, this new model provides a robust numerical tool to forecast the impact of lianas on tropical forest carbon sinks.

show abstract

Blurred lines between competition and parasitism

Cited by 25 publications

References 43 publications

Lianas have a seasonal growth advantage over co‐occurring trees

Lianas have a seasonal growth advantage over co‐occurring trees

Conceptualising the Global Forest Response to Liana Proliferation

Modeling the impact of liana infestation on the demography and carbon cycle of tropical forests

Contact Info

Product

Resources

About