To estimate the relative contributions of woody and herbaceous vegetation to savanna productivity, we measured the 13C/12C isotopic ratios of leaves from trees, shrubs, grasses and the surface soil carbon pool for 22 savannas in Australia, Brazil and Ghana covering the full savanna spectrum ranging from almost pure grassland to closed woodlands on all three continents. All trees and shrubs samp...

Water is a limiting factor for plant growth and vegetation dynamics in alpine sandy land of the Tibetan Plateau, especially with the increasing frequency of extreme precipitation events and drought caused by climate change. Therefore, a relatively stable water source from either deeper soil profiles or ground water is necessary for plant growth. Understanding the water use strategy of dominant ...

Plant communities in natural ecosystems are changing and species are being lost due to anthropogenic impacts including global warming and increasing nitrogen (N) deposition. We removed dominant species, combinations of species and entire functional types from Alaskan tussock tundra, in the presence and absence of fertilization, to examine the effects of non-random species loss on plant interact...

The chaparral shrub community is dominated by evergreen sclerophyllous shrubs and primarily occurs in southern California (Fig. 7.1a) (Parker et al. in press). The chaparral has probably been more studied in an ecophysiological context than any other natural vegetation type in the world. The species that dominate this vegetation type have proven to be excellent model organisms for a range of ph...

In Bevan et al. (2016), the study of patterns in forests of binary shrubs was introduced. A k-ary heap H is a k-ary tree labeled with {1, . . . , n} such that every child has a larger label than its parent. Given a k-ary heap H , we associate a permutation σH with H by recording the vertex labels as they are encountered in the breadth-first search of the tree. For example, in Figure 1, we pictu...

Root growth of Cucumis and Avena seedlings is inhibited by volatile materials produced by leaves of Salvia leucophylla, S. apiana, and Artemisia californica. The toxic substance may be deposited when dew condenses on affected seedlings in the field.

Spatial heterogeneity of abiotic factors influences patterns of seedling establishment at different scales. In stress-prone ecosystems such as Mediterranean ones, heterogeneity generated by shrubs has been shown to facilitate the establishment of tree species. However, how this facilitation is affected by spatial scale remains poorly understood. We have experimentally analysed the consequences ...

Spatial distribution of palatable and unpalatable plants can influence the foraging behaviour of herbivores, thereby changing plant-damage probabilities. Moreover, the immediate proximity to certain plants can benefit other plants that grow below them, where toxicity or spines act as a physical barrier or concealment against herbivores. This paper presents the results of a multi-scale experimen...