Plant and lemur responses to forest edges in Madagascar

生态学和保护生物学中的一个基本问题是确定森林边缘如何影响动植物群落。森林边缘是森林和非森林环境之间的动态地带，或者是两个组成或结构截然不同的生境之间的动态地带。在世界许多地区，森林正变得越来越支离破碎，这导致边缘栖息地在每个支离物中所占比例更大。边缘影响可以通过碎片级别的影响发生，例如资源丰度的空间变异性，以及景观级别的影响，例如群落结构的变化。对于马达加斯加的狐猴来说，这些问题具有特别的生态意义和保护关注，因为人类已经改变了岛上大约90%的原始森林。虽然概念模型已被用来调查动物对森林边缘的反应，但相关的预测最好适用于利用该基质的分类群(例如，非森林生境)。那么，问题就出现了，对于不使用矩阵的森林动物，如大多数狐猴，模型的表现如何。我建议在马达加斯加西北部的安卡拉芬西卡国家公园及其周围的碎片和景观层面上进行两个新的研究项目。首先，我和我的学生们将使用观测和实验研究来检验有关森林边缘如何影响植物群落动态、树枝计量学和非生物因素的假设。其次，我们将测试最近概念模型中关于边缘对狐猴丰度(密度和生物量)和行为生态学(饮食、活动和测距模式)的影响的假设。我们将把我们的狐猴研究重点放在两种食叶动物(欧洲狐猴和西方狐猴)、两种食果动物(叶猴和蒙古狐猴)、一种食叶/果食动物(龙猴)和三种杂食性动物(雷氏小狐猴、小狐猴和中间小狐猴)上。这项拟议的研究具有特别重要的意义，因为它测试了各种空间尺度上的边缘影响假说，将数据应用于严重的保护问题，并支持来自加拿大和马达加斯加的高素质人员的培训。

A fundamental issue in ecology and conservation biology is determining how forest edges influence plant and animal communities. Forest edges are dynamic zones between forested and nonforested environments or between two habitats of contrasting composition or structure. Forests are becoming increasingly fragmented in many parts of the world, which results in edge habitats comprising a proportionally larger part of each fragment. Edge influences can occur through fragment-level impacts, such as spatial variability in resource abundance, and landscape-level impacts, such as changes in community structure. For the lemurs of Madagascar, these issues are of particular ecological interest and conservation concern because humans have transformed approximately 90% of the primary forests on the island. Although conceptual models have been used to investigate animal responses to forest edges, the associated predictions are best applied to taxa that exploit the matrix (e.g., nonforested habitats). The question arises then as to how models perform for forest-dwelling animals, such as most lemurs, that do not use the matrix. I propose two new research projects at the fragment and landscape levels in and around Ankarafantsika National Park in northwest Madagascar. First, my students and I will use observational and experimental studies to test hypotheses on how forest edges influence plant community dynamics, dendrometrics, and abiotic factors. Second, we will test hypotheses from recent conceptual models on edge influences on lemur abundance (density and biomass) and behavioral ecology (diet, activity, and ranging patterns). We will focus our lemur studies on two folivores (Lepilemur edwardsi and Avahi occidentalis), two frugivores (Eulemur fulvus and Eulemur mongoz), one folivore/frugivore (Propithecus coquereli), and three omnivores (Microcebus ravelobensis, Microcebus murinus, and Cheirogaleus medius). The proposed research is of special significance because it tests hypotheses on edge influences at various spatial scales, applies data to serious conservation issues, and supports the training of highly qualified personnel from Canada and Madagascar.