Treesearch

Building on the eco-hydrological insights reviewed in Chapter 2 and the ongoing change in determinants of the forest-water relationship in Chapter 3, this chapter aims to clarify the effects that changing climate and quantity, quality and pattern of tree cover in forests have on the way water becomes available for human use and ecosystem integrity. To do this, the chapter synthesises current understanding of implications for local and global hydrology of current and anticipated changes to forests and tree cover.

As outlined in Chapter 2, our analysis of forest-water relations addresses four important subsystems of a linked planetary social-ecological system: climate, forests, water and people. In this chapter, we consider how each of these subsystems is changing (trend) and what is causing the change (’determinant’). We discuss the critical determinants of change in forests as they relate to water quality and quantity. Chapter 4 then presents the impacts of these changes on water quality and quality.

Despite serving as invasion gateways for non-native forest pests, urban forests are less well understood than natural forests. For example, only a fraction of communities in the USA and Canada have completed urban forest inventories, and most have been limited to street trees; sample-based inventories that provide valid communitywide estimates of urban forest composition are much rarer. As a proof of concept, we devised a three-step approach to model urban tree distributions regionally using available street tree and whole-community inventory data. We illustrate the approach for three tree...

This chapter addresses potential forest and water management strategies based on our understanding of the ‘new normal’, the challenges imposed, in particular, by climate change and human population growth, and our evolving knowledge of forest-water interactions. It further considers forest and water management strategies when water is prioritised over other forest-related goals (such as biomass accumulation or the sequestration of carbon in standing forests). Explicitly prioritising water in forest management attempts to reset our priorities toward more sustainable strategies for long-term...

This chapter utilises the ecosystem services framework to understand the consequences of change in forest ecosystem functions and water-related implications. Using a scenario analysis, the chapter explores the likely changes in attributes of forest-water systems (and associated services) that will translate to exogenous impacts, and their consequences in the future. The narrative provides a foundation for the analysis of management options and policy responses that will be discussed in Chapters 6 and 7. Ultimately, these responses are likely to affect the drivers of change and thus...

Information about how bird species respond to increasing density conditions through either space‐use sharing or increased territoriality, and how those changes affect fitness, is essential for effective conservation planning. We used a case study of endangered Red‐cockaded Woodpeckers Leuconotopicus borealis (RCW) to address these questions. We documented over 36 000 locations from 44 RCW groups in three density conditions on two sites in South Carolina, USA, between April 2013 and March 2015. The frequency of neighbouring group interactions differed among density conditions and was...

WaSSI-C is an ecohydrological model which couples water and carbon cycles with water use efficiency (WUE) derived from global eddy flux observations. However, a significant limitation of the WaSSI-C model is that it only runs serially. High resolution simulations at a large scale are therefore computationally expensive and cause a run-time memory burden. Using distributed (MPI) and shared (OpenMP) memory parallelism techniques, we revised the original model as dWaSSI-C. We showed that using MPI was effective in reducing the computational run-time and memory use. Two experiments were...

Water is essential to life on Earth. Ecohydrology, the study of interactions between ecological and hydrological processes, is fundamental to our understanding and quantification of services provided by ecosystems. Our knowledge of ecohydrology is incomplete due to the complex nature of ecosystems, which are constantly changing under multiple stresses from air pollution to climate change, from deforestation to urbanization, and from soil erosion to soil pollution. Ecosystem services, the goods and services that ecosystems provide for human wellbeing, are increasingly adopted as a framework...

We generated a large-scale mangrove forest height map using multiple TanDEM-X (TDX) interferometric synthetic aperture radar (InSAR) acquisitions with various spatial baselines in order to improve the height estimation accuracy across a wide range of forest heights. The forest height inversion using InSAR data is strongly dependent upon the vertical wavenumber (i.e., perpendicular baseline). First, we investigated the role of the vertical wavenumber in forest height inversion from InSAR data using the sensitivity of the interferometric (volume) coherence to forest height. We used corrected...

The objective of this study is to estimate the biomass and carbon of global-level mangroves as a special type of wetland. Mangrove ecosystems play an important role in regulating carbon cycling, thus having a significant impact on global environmental change. Extensive studies have been conducted for the estimation of mangrove biomass and carbon stock. However, this estimation at a global level has been insufficiently investigated because the spatial scale of interest is large and most existing studies are based on physically challenging fieldwork surveys that are limited to local scales....