Trends over time in tree and seedling phylogenetic diversity indicate regional differences in forest biodiversity change

Sunken trees in the deep sea link terrestrial and marine biodiversity

Wood in the deep sea serves as a substantial food source in an otherwise barren environment, forming specialized, endemic, and diverse community assemblages. This biodiversity reliance on a terrestrial source creates a linkage by which anthropogenic impacts on land can alter the deep oceans. Knowledge of the alpha- or beta-diversity of entire wood-fall communities, and wooden drivers of each would elucidate the terrestrial and deep-sea linkage. We report on a multifactorial experiment in the deep ocean in which alpha- and beta-diversity of 43 wood falls and 11 tree species are quantified over time, wood density, and wood size. We tested multiple hypotheses seeking to link how biodiversity on land may impact the biodiversity in the deep oceans. A tremendous biodiversity occurred among these wood falls in the deep Gulf of Mexico; 114 invertebrate species from 10 phyla. Time, wood hardness, and wood size all impacted various components of community structure. In many cases, these effects were additive. Species occurring on softwoods versus hardwoods and small versus large wood falls were compositionally different. Although various processes can control community structure, this experiment suggests a strong influence of environmental filtering and host specificity of wood-fall invertebrates suggesting an intimate coupling to tree biodiversity and biomass on land.

A planning tool for tree species selection and planting schedule in forestation projects considering environmental and socio-economic benefits

Species selection is a crucial step in the planning phase of forestation programs given its impact on the results and on stakeholder interactions. This study develops a planning tool for forestation programs that incorporates the selection of tree species and the scheduling of planting and harvesting, while balancing the maximization of the carbon sequestered and income realized, into the forestation decision-making and planning process. The validation of the goal programming model formulated demonstrates that the characteristics of natural tree species along with the behavior of growth and timing of yield are significant factors in achieving the environmental and socio-economic aspirations. The proposed model is therefore useful in gauging species behavior and performance over time. Sensitivity analysis was also conducted where the behavior of the income generated and carbon sequestered with respect to the external factors such as carbon market prices, percentage area allocated for protection and discount factor was assessed.

Biodiversity and evolutionary history: useful extensions of the PD phylogenetic diversity assessment framework

Evolutionary biology is a core discipline in biodiversity science. Evolutionary history or phylogeny provides one natural measure of biodiversity through the popular phylogenetic diversity (PD) measure. The evolutionary model underlying PD means that it can be interpreted as quantifying the relative feature diversity of sets of species. Quantifying feature diversity measures possible future uses and benefits or option values. Interpretation of PD as counting-up features is the basis for an emerging broad family of PD calculations, of use to both biodiversity researchers and decision makers. Many of these calculations extend conventional species-level indices to the features level. Useful PD calculations include PD complementarity and endemism, Hill and Valley numbers incorporating abundance, and PD dissimilarities. A flexible analysis framework is provided by expected PD calculations, applied to either probabilities of extinction or presence-absence. Practical extensions include phylogenetic risk analysis and measures of distinctiveness and endemism. These support the integration of phylogenetic diversity into biodiversity conservation and monitoring programs.

Climate change impacts on the tree of life: changes in phylogenetic diversity illustrated for acropora corals

The possible loss of whole branches from the tree of life is a dramatic, but under-studied, biological implication of climate change. The tree of life represents an evolutionary heritage providing both present and future benefits to humanity, often in unanticipated ways. Losses in this evolutionary (evo) life-support system represent losses in "evosystem" services, and are quantified using the phylogenetic diversity (PD) measure. High species-level biodiversity losses may or may not correspond to high PD losses. If climate change impacts are clumped on the phylogeny, then loss of deeper phylogenetic branches can mean disproportionately large PD loss for a given degree of species loss. Over time, successive species extinctions within a clade each may imply only a moderate loss of PD, until the last species within that clade goes extinct, and PD drops precipitously. Emerging methods of "phylogenetic risk analysis" address such phylogenetic tipping points by adjusting conservation priorities to better reflect risk of such worst-case losses. We have further developed and explored this approach for one of the most threatened taxonomic groups, corals. Based on a phylogenetic tree for the corals genus Acropora, we identify cases where worst-case PD losses may be avoided by designing risk-averse conservation priorities. We also propose spatial heterogeneity measures changes to assess possible changes in the geographic distribution of corals PD.