Results 221 to 230 of about 217,153 (254)

Experimental and observational evidence of negative conspecific density dependence in temperate ectomycorrhizal trees

Ecology, 2022
AbstractConspecific negative density dependence (CNDD) promotes tree species diversity by reducing recruitment near conspecific adults due to biotic feedbacks from herbivores, pathogens, or competitors. While this process is well‐described in tropical forests, tests of temperate tree species range from strong positive to strong negative density ...
Fiona V Jevon, Joseph A Lamanna, Ashley K Lang   +2 more
exaly   +3 more sources

Measuring the demographic impact of conspecific negative density dependence

Oecologia, 2017
Rare plant species often suffer stronger conspecific negative density dependence (CNDD) in studies that assess the impact of local conspecific density on individual survival. All else equal, this causes a relative disadvantage among rare species that appears inconsistent with the role of CNDD in coexistence.
Fricke, Evan C., Wright, S. Joseph
openaire   +3 more sources

Herbivores as drivers of negative density dependence in tropical forest saplings

Science, 2019
Herbivores shape tropical forests In tropical forests, high local tree diversity is driven by negative density dependence, a process whereby plant performance is inhibited by closely related neighbors. Negative density dependence could be caused by competition for resources among neighbors or result from shared ...
Dale L. Forrister, María-José Endara, Gordon C. Younkin, Phyllis D. Coley, Thomas A. Kursar   +4 more
openaire   +2 more sources

Bottom-Up Effects and Conspecific Negative Density Dependence in a Subtropical Forest

2023
The early growth stage of plants is vital to community diversity and community regeneration. Understandably, it is critical to explore the mechanisms underpinning the spatial and temporal dynamic patterns of seedling survival and growth. The Janzen–Connell hypothesis predicts that conspecific density dependence lowers the survival of conspecific ...
Gang Zhou, Yuanzhi Qin, Daniel Petticord, Xiujuan Qiao, Mingxi Jiang   +4 more
openaire   +1 more source

Simultaneous positive and negative density‐dependent dispersal in a colonial bird species

Ecology, 2009
Contradictory patterns of density‐dependent animal dispersal can potentially be reconciled by integrating the conspecific attraction hypothesis with the traditional competition hypothesis. We propose a hypothesis that predicts a U‐shaped relationship between density and both natal and breeding dispersal distance.
Sin-Yeon, Kim, Roxana, Torres, Hugh, Drummond   +2 more
openaire   +2 more sources

Plant diversity increases with the strength of negative density dependence at the global scale

Science, 2017
Maintaining tree diversity Negative interaction among plant species is known as conspecific negative density dependence (CNDD). This ecological pattern is thought to maintain higher species diversity in the tropics. LaManna et al.
Joseph A. LaManna, Scott A. Mangan, Alfonso Alonso, Norman A. Bourg, Warren Y. Brockelman, Sarayudh Bunyavejchewin, Li-Wan Chang, Jyh-Min Chiang, George B. Chuyong, Keith Clay, Richard Condit, Susan Cordell, Stuart J. Davies, Tucker J. Furniss, Christian P. Giardina, I. A. U. Nimal Gunatilleke, C. V. Savitri Gunatilleke, Fangliang He, Robert W. Howe, Stephen P. Hubbell, Chang-Fu Hsieh, Faith M. Inman-Narahari, David Janík, Daniel J. Johnson, David Kenfack, Lisa Korte, Kamil Král, Andrew J. Larson, James A. Lutz, Sean M. McMahon, William J. McShea, Hervé R. Memiaghe, Anuttara Nathalang, Vojtech Novotny, Perry S. Ong, David A. Orwig, Rebecca Ostertag, Geoffrey G. Parker, Richard P. Phillips, Lawren Sack, I-Fang Sun, J. Sebastián Tello, Duncan W. Thomas, Benjamin L. Turner, Dilys M. Vela Díaz, Tomáš Vrška, George D. Weiblen, Amy Wolf, Sandra Yap, Jonathan A. Myers   +49 more
openaire   +3 more sources

Experimental evidence that density mediates negative frequency‐dependent selection on aggression

Journal of Animal Ecology, 2018
Abstract Aggression can be beneficial in competitive environments if aggressive individuals are more likely to access resources than non‐aggressive individuals. However, variation in aggressive behaviour persists within populations, suggesting that high levels of aggression might not always be favoured.
R. Julia Kilgour, Andrew G. McAdam, Gustavo S. Betini, D. Ryan Norris   +3 more
openaire   +2 more sources

Density dependence on negative corona onset voltage in helium

Seventh International Conference on Dielectric Materials, Measurements and Applications, 1996
This paper presents the results of experiments in gaseous helium, in point cathode-plane geometry, for a wide range of densities (3.10/sup 19/-2.10/sup 21/) cm/sup -3/. A current instability occurs at a threshold voltage V/sub S/. For V>V/sub S/, a space charge limited current is observed. The nature of charge carriers deduced from their mobility value
openaire   +1 more source

Dependency of the electronegative sheath structure on the negative ion density and temperature

2009 IEEE International Conference on Plasma Science - Abstracts, 2009
Some general aspects of the sheath structure in electronegative plasmas are analysed, through an extensive review of the authors' contributions to this subject. In this work, the onedimensional collisionless sheath model of electropositive plasmas is investigated extended here to study the sheath structure of an electronegative plasma at steady state ...
M. Sharifian, B. Shokri, A. R. Niknam
openaire   +1 more source

Conspecific negative density‐dependent mortality and the structure of temperate forests

Ecology, 2014
Factors that control tree seedling dynamics are critical determinants of forest diversity. We examined the role of density‐dependent mortality and abiotic factors in the differential establishment and survival of tree seedlings at three, large, mapped forest plots in Indiana, Virginia, and Wisconsin, USA.
Johnson, Daniel J., Bourg, Norman Alan, Howe, Robert, McShea, William J., Wolf, Amy T., Clay, Keith   +5 more
openaire   +2 more sources