Díaz-Sierra R, Zavala M A, Rietkerk M
Dpt. de Física Matemática y de Fluidos, Univ. Nacional de Educación a Distancia, Apartado 60141, 28080 Madrid, Spain.
Theor Popul Biol. 2010 Mar;77(2):131-44. doi: 10.1016/j.tpb.2009.12.001. Epub 2009 Dec 24.
The population and community level consequences of positive interactions between plants remain poorly explored. In this study we incorporate positive resource-mediated interactions in classic resource competition theory and investigate the main consequences for plant population dynamics and species coexistence. We focus on plant communities for which water infiltration rates exhibit positive dependency on plant biomass and where plant responses can be improved by shading, particularly under water limiting conditions. We show that the effects of these two resource-mediated positive interactions are similar and additive. We predict that positive interactions shift the transition points between different species compositions along environmental gradients and that realized niche widths will expand or shrink. Furthermore, continuous transitions between different community compositions can become discontinuous and bistability or tristability can occur. Moreover, increased infiltration rates may give rise to a new potential coexistence mechanism that we call controlled facilitation.
植物之间积极相互作用在种群和群落层面的后果仍未得到充分研究。在本研究中，我们将积极的资源介导相互作用纳入经典资源竞争理论，并研究其对植物种群动态和物种共存的主要影响。我们关注那些水分渗透率对植物生物量呈正相关依赖，且植物响应可通过遮荫得到改善的植物群落，特别是在水分限制条件下。我们发现这两种资源介导的积极相互作用的效果相似且具有累加性。我们预测，积极相互作用会沿着环境梯度移动不同物种组成之间的转变点，并且实际生态位宽度会扩大或缩小。此外，不同群落组成之间的连续转变可能会变得不连续，并且可能出现双稳态或三稳态。而且，渗透率的增加可能会产生一种我们称之为受控促进作用的新的潜在共存机制。
