The concept of Diffusion Tensor Imaging (DTI) is often difficult to grasp, even for Magnetic Resonance physicists. Introduction to Diffusion Tensor Imaging uses extensive illustrations (not ...equations) to help readers to understand how DTI works. Emphasis is placed on the interpretation of DTI images, the design of DTI experiments, and the forms of application studies. The theory of DTI is constantly evolving and so there is a need for a textbook that explains how the technique works in a way that is easy to understand - Introduction to Diffusion Tensor Imaging fills this gap.* Uses extensive illustrations to explain the concept of Diffusion Tensor Imaging * Easy to understand, even without a background in physics * Includes sections on image interpretation, experimental design and applications
1. Given the substantial contributions of forest biodiversity and ecosystem services to society, forest sciences have a large potential to contribute to the integrity and sustainability of our ...future. This is especially true when the roles of biodiversity for sustaining ecosystem services are considered. 2. The rapid expansion of sustainable forest management (SFM) has resulted in the adoption of various forest management frameworks intended to safeguard biodiversity. Concurrently, the importance of forest ecosystem services has been increasingly recognized. Although some initiatives aimed at conserving both biodiversity and ecosystem services are emerging, knowledge gaps still exist about their relationships and potential trade-offs in forests. Given recent advancements, increasing opportunities and some lags in forest ecology, further research on biodiversity, ecosystem functions and services will play substantial roles in the development of SFM practices. 3. Here, we identified key issues including (i) relationships between biodiversity and ecosystem function as a foundation of ecological integrity, (ii) resilience thinking to better prepare for and adapt to environmental changes, (iii) social-ecological perspectives that facilitate realworld conservation and management and (iv) theory-driven restoration that bridges science and practice. Thus, we illustrate priorities and future possibilities in applied ecology studies in forests, which will help society and ecosystems to build capacity and resilience to face uncertainty in the changing environment. 4. Synthesis and applications. Under substantial human influences, forests are highly likely to be largely altered, potentially leading to the emergence of novel ecosystems or alternative stable states. Management thus needs more flexible, novel measures to address the significant uncertainty this generates. Resilience-based approaches are important to respond adaptively to future changes and cope with surprises, potentially providing multiple options. Although challenges exist, theory should play an important role in managing, conserving and restoring forest ecosystems. The issues discussed here should receive further attention in the context of the multiple goals of sustainable forest management.
ABSTRACT
A growing body of evidence highlights the importance of biodiversity for ecosystem stability and the maintenance of optimal ecosystem functionality. Conservation measures are thus essential ...to safeguard the ecosystem services that biodiversity provides and human society needs. Current anthropogenic threats may lead to detrimental (and perhaps irreversible) ecosystem degradation, providing strong motivation to evaluate the response of ecological communities to various anthropogenic pressures. In particular, ecosystem functions that sustain key ecosystem services should be identified and prioritized for conservation action. Traditional diversity measures (e.g. ‘species richness’) may not adequately capture the aspects of biodiversity most relevant to ecosystem stability and functionality, but several new concepts may be more appropriate. These include ‘response diversity’, describing the variation of responses to environmental change among species of a particular community. Response diversity may also be a key determinant of ecosystem resilience in the face of anthropogenic pressures and environmental uncertainty. However, current understanding of response diversity is poor, and we see an urgent need to disentangle the conceptual strands that pervade studies of the relationship between biodiversity and ecosystem functioning. Our review clarifies the links between response diversity and the maintenance of ecosystem functionality by focusing on the insurance hypothesis of biodiversity and the concept of functional redundancy. We provide a conceptual model to describe how loss of response diversity may cause ecosystem degradation through decreased ecosystem resilience. We explicitly explain how response diversity contributes to functional compensation and to spatio‐temporal complementarity among species, leading to long‐term maintenance of ecosystem multifunctionality. Recent quantitative studies suggest that traditional diversity measures may often be uncoupled from measures (such as response diversity) that may be more effective proxies for ecosystem stability and resilience. Certain conclusions and recommendations of earlier studies using these traditional measures as indicators of ecosystem resilience thus may be suspect. We believe that functional ecology perspectives incorporating the effects and responses of diversity are essential for development of management strategies to safeguard (and restore) optimal ecosystem functionality (especially multifunctionality). Our review highlights these issues and we envision our work generating debate around the relationship between biodiversity and ecosystem functionality, and leading to improved conservation priorities and biodiversity management practices that maximize ecosystem resilience in the face of uncertain environmental change.
Biodiversity loss and climate change are often considered as intertwined issues. However, they do not receive equal attention. Even in the context of nature‐based climate solutions, which consider ...ecosystems to be crucial to mitigate and adapt to the impacts of climate change, the potential role of biodiversity has received little attention. Here this essay emphasizes biodiversity as the cause—not only the consequence—to help society and nature face challenges associated with the changing climate. Reconsidering and emphasizing the linkages between these twin environmental crises is urgently needed to make collective efforts for the environment truly effective.
Naturally‐functioning ecosystems, supported by biodiversity, are crucial to face many socio‐environmental issues including climate change. However, biodiversity loss and climate change do not receive equal attention to date. Putting biodiversity at the heart of nature‐based approaches is crucial to make collective efforts for the environment truly effective.
1. Maintenance of ecological integrity and biodiversity must be based on well-grounded principles of disturbance ecology. However, non-equilibrium aspects of ecosystems, such as unpredictability, ...instability and stochasticity due to various natural disturbances, have not been satisfactorily integrated into practical application. Failure to acknowledge the dynamic nature of systems will inevitably lead to unexpected changes and unachieved conservation goals. 2. This review discusses non-equilibrium ecology in terms of natural disturbances and the conservation and management of terrestrial ecosystems and landscapes. 3. Several key components, which require further ecological consideration, are specifically discussed. These include the hierarchical disturbance regime, disturbance legacy, multiple post-disturbance pathways, climate instability, spatial and temporal variability, and resilience. 4. Natural disturbance regimes are complex and difficult to define. This is because some disturbances can be nested, and they interact with other qualitatively and quantitatively different disturbances, constituting a hierarchy of natural disturbances. Large temporal and spatial perspectives are therefore required to incorporate the hierarchical context of natural disturbance regimes into regional management plans. 5. Conservation managers may often seek some kind of dynamic equilibrium based on protection of species and seral stages from extinction. However, because climate instability interrupts any shift toward an equilibrium, most terrestrial vegetation systems are inherently prone to large environmental changes and diverse disturbances, and thus, are dynamic and non-equilibrating. 6. Synthesis and applications. Resiliency is the key to conserving ecological integrity via the ability to cope with inevitable changes. As long as ecosystems are resilient and disturbances are natural, we should not impede natural shifts in disturbance regimes and resultant ecosystem changes, even if changes are abrupt and unpredictable and thus have large consequences. If ecological resilience has already been eroded by humans, it is important that resilience should be enhanced by restoring keystone features of vegetation systems to prevent disturbance-induced undesirable ecosystem degradation.
1. Knowledge of the functional consequences of biodiversity is increasing through studies of both experimental systems and natural systems. Community assembly theory has also helped to reveal the ...causes of biodiversity organization. However, the causes and consequences of biodiversity have been discussed in parallel and simultaneous consideration of both has been limited, even though they are both influenced by regional environmental conditions. 2. To understand the relationship between biodiversity and productivity, I focused on the linkages between the number of tree species and biomass productivity across forest biomes under a range of bioclimatic conditions. 3. I found that high tree diversity generally increased productivity. This was primarily due to a selection process that results from a high probability of having high-performance species and their dominance at high diversity, regardless of the biome. In less-productive biomes, the residual importance of diversity, which likely reflects other forms of biological interactions (including species complementarity), increased productivity. 4. These findings of differential diversity effects under different environmental conditions are consistent with the existing theory of community assembly, which predicts a shift in the assembly process from stochasticity to determinism with increasing environmental harshness. Analyses based on functional trait diversity also supported this theory: stochastic assembly (resulting in the selection effect) and deterministic assembly (possibly resulting from interspecific niche differences) became more important in productive and less-productive biomes, respectively. 5. Synthesis. Increasing our understanding of the causalities between diversity and other characteristics, such as productivity, is crucial, particularly for forest ecosystems, because of the increasing interest in productivity-related ecosystem services supported by diverse assemblages of trees.
Currently, there is an increasing need for sustainable forest management to meet multiple beneficial social and ecological goals. This has spurred the emergence of retention forestry, which aims to ...maintain key elements of the stand during harvesting to ameliorate the post-logging structure over forest generations. Despite the global expansion of this approach as a conservation tool in production forests, quantitative evaluations of its effectiveness are still lacking, particularly for comparisons across different biomes, different levels of economic development, and different taxa. We conducted a meta-analysis to identify the general responses of forest species to the set-aside actions (i.e., retaining the important biotic and abiotic features during logging to conserve biodiversity). We found that retention forestry can preserve a degree of species richness equivalent to that of primary forests, at least at the stand level. This potential does not differ among regions or economic development levels, supporting the ecological meaning of retaining “biological legacies” over forest generations irrespective of forest biomes. Despite their common focus on biodiversity conservation, retention forestry is different from the reduced-impact forestry that is implemented with selective logging. The reason for this difference is that the former and the latter approach focus on what is retained and what is logged during harvesting operations, respectively. Thus, our meta-analysis also focused on comparisons between these two logging methods based on different viewpoints, i.e., from the species perspective vs. the perspective of human needs. We found that although selective logging was not detrimental to forest taxa, retention forestry was more effective in conserving biodiversity. We thus argue that the principles underpinned by retention approach, such as the consideration of natural disturbance regimes, and the provision of important habitats for species, will be essential overall for biodiversity-oriented forestry. Retention forestry will continue to play a fundamental role in encouraging further development of management schemes that have multiple goals.
Abstract
Biodiversity loss can alter ecosystem functioning; however, it remains unclear how it alters decomposition—a critical component of biogeochemical cycles in the biosphere. Here, we provide a ...global-scale meta-analysis to quantify how changes in the diversity of organic matter derived from plants (i.e. litter) affect rates of decomposition. We find that the after-life effects of diversity were significant, and of substantial magnitude, in forests, grasslands, and wetlands. Changes in plant diversity could alter decomposition rates by as much as climate change is projected to alter them. Specifically, diversifying plant litter from mono- to mixed-species increases decomposition rate by 34.7% in forests worldwide, which is comparable in magnitude to the 13.6–26.4% increase in decomposition rates that is projected to occur over the next 50 years in response to climate warming. Thus, biodiversity changes cannot be solely viewed as a response to human influence, such as climate change, but could also be a non-negligible driver of future changes in biogeochemical cycles and climate feedbacks on Earth.
Using Lorenz microscopy and small-angle electron diffraction, we directly present that the chiral magnetic soliton lattice (CSL) continuously evolves from a chiral helimagnetic structure in small ...magnetic fields in Cr(1/3)NbS2. An incommensurate CSL undergoes a phase transition to a commensurate ferromagnetic state at the critical field strength. The period of a CSL, which exerts an effective potential for itinerant spins, is tuned by simply changing the field strength. Chiral magnetic orders observed do not exhibit any structural dislocation, indicating their high stability and robustness in Cr(1/3)NbS2.
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