Our future in the Anthropocene biosphere

The COVID-19 pandemic has exposed an interconnected and tightly coupled globalized world in rapid change. This article sets the scientific stage for understanding and responding to such change for global sustainability and resilient societies. We provide a systemic overview of the current situation where people and nature are dynamically intertwined and embedded in the biosphere, placing shocks and extreme events as part of this dynamic; humanity has become the major force in shaping the future of the Earth system as a whole; and the scale and pace of the human dimension have caused climate change, rapid loss of biodiversity, growing inequalities, and loss of resilience to deal with uncertainty and surprise. Taken together, human actions are challenging the biosphere foundation for a prosperous development of civilizations. The Anthropocene reality-of rising system-wide turbulence-calls for transformative change towards sustainable futures. Emerging technologies, social innovations, broader shifts in cultural repertoires, as well as a diverse portfolio of active stewardship of human actions in support of a resilient biosphere are highlighted as essential parts of such transformations.

Conserving tropical nature: current challenges for ecologists

Tropical biodiversity continues to erode unabated, which calls for ecologists to address the problem directly, placing less reliance on indirect interventions, such as community-based development schemes. Ecologists must become more assertive in providing scientifically formulated and adaptively managed interventions, involving biodiversity payments, to serve local, regional and global interests in tropical nature. Priorities for tropical ecologists thus include the identification of key thresholds to ecological resilience, and the formulation of clear monitoring protocols and management strategies for implementation by local resource managers. A particular challenge is to demonstrate how nature reserves contribute to the adaptive capacity of regional land-use matrices and, hence, to the provision of sustainable benefits at multiple spatial and temporal scales.

Rangelands, pastoralists and governments: interlinked systems of people and nature

We analyse commercially operated rangelands as coupled systems of people and nature. The biophysical components include: (i) the reduction and recovery of potential primary production, reflected as changes in grass production per unit of rainfall; (ii) changes in woody plants dependent on the grazing and fire regimes; and (iii) livestock and wool dynamics influenced by season, condition of the rangeland and numbers of wild and feral animals. The social components include the managers, who vary with regard to a range of cognitive abilities and lifestyle choices, and the regulators who vary in regard to policy goals. We compare agent-based and optimization models of a rangeland system. The agent-based model leads to recognition that policies select for certain management practices by creating a template that governs the trajectories of the behaviour of individuals, learning, and overall system dynamics. Conservative regulations reduce short-term loss in production but also restrict learning. A free-market environment leads to severe degradation but the surviving pastoralists perform well under subsequent variable conditions. The challenge for policy makers is to balance the needs for learning and for preventing excessive degradation. A genetic algorithm model optimizing for net discounted income and based on a population of management solutions (stocking rate, how much to suppress fire, etc.) indicates that robust solutions lead to a loss of about 40% compared with solutions where the sequence of rainfall was known in advance: this is a similar figure to that obtained from the agent-based model. We conclude that, on the basis of Levin's three criteria, rangelands with their livestock and human managers do constitute complex adaptive systems. If this is so, then command-and-control approaches to rangeland policy and management are bound to fail.

Provision of nutrition counseling, referrals to registered dietitians, and sources of nutrition information among practicing chiropractors in the United States

OBJECTIVE

To investigate US chiropractors' provision of nutrition counseling and referrals to registered dietitians and sources of nutrition information. Chiropractors' perceptions of the minimum educational requirement for registered dietitians and nutrition training received in chiropractic school were also examined.

DESIGN

A descriptive study was conducted by use of a nationwide, mailed survey.

SUBJECTS/SETTING

Surveys were sent to 1,590 practicing chiropractors in the United States, selected randomly from The National Directory of Chiropractic. Of the 410 responses received, 375 were usable (response rate = 23.6%).

STATISTICAL ANALYSIS

Descriptive statistics were used to summarize data along with the Pearson chi 2 test and Kendall tc rank correlation to determine associations for categorical questions.

RESULT

Nearly 90% of respondents provided nutrition counseling to their patients, even though the majority believed that they were inadequately trained in nutrition. One-on-one dietary instruction was the most common method of providing nutrition counseling, and supplement use was the most common health-related situation/condition for which nutrition counseling was used. Most respondents did not correctly select the minimum educational requirement for registered dietitians, did not refer patients to registered dietitians, and did not use registered dietitians as a source of nutrition information. Nevertheless, 65% of respondents anticipated increased collaborations between registered dietitians and chiropractors.

APPLICATIONS/CONCLUSIONS

Chiropractors provide nutrition counseling to a large number of patients each year; thus, they have the potential to substantially affect patients' nutritional status. There is a clear need and opportunity for registered dietitians to collaborate with chiropractors.

Global biodiversity scenarios for the year 2100

Scenarios of changes in biodiversity for the year 2100 can now be developed based on scenarios of changes in atmospheric carbon dioxide, climate, vegetation, and land use and the known sensitivity of biodiversity to these changes. This study identified a ranking of the importance of drivers of change, a ranking of the biomes with respect to expected changes, and the major sources of uncertainties. For terrestrial ecosystems, land-use change probably will have the largest effect, followed by climate change, nitrogen deposition, biotic exchange, and elevated carbon dioxide concentration. For freshwater ecosystems, biotic exchange is much more important. Mediterranean climate and grassland ecosystems likely will experience the greatest proportional change in biodiversity because of the substantial influence of all drivers of biodiversity change. Northern temperate ecosystems are estimated to experience the least biodiversity change because major land-use change has already occurred. Plausible changes in biodiversity in other biomes depend on interactions among the causes of biodiversity change. These interactions represent one of the largest uncertainties in projections of future biodiversity change.

Global biodiversity scenarios for the year 2100

Scenarios of changes in biodiversity for the year 2100 can now be developed based on scenarios of changes in atmospheric carbon dioxide, climate, vegetation, and land use and the known sensitivity of biodiversity to these changes. This study identified a ranking of the importance of drivers of change, a ranking of the biomes with respect to expected changes, and the major sources of uncertainties. For terrestrial ecosystems, land-use change probably will have the largest effect, followed by climate change, nitrogen deposition, biotic exchange, and elevated carbon dioxide concentration. For freshwater ecosystems, biotic exchange is much more important. Mediterranean climate and grassland ecosystems likely will experience the greatest proportional change in biodiversity because of the substantial influence of all drivers of biodiversity change. Northern temperate ecosystems are estimated to experience the least biodiversity change because major land-use change has already occurred. Plausible changes in biodiversity in other biomes depend on interactions among the causes of biodiversity change. These interactions represent one of the largest uncertainties in projections of future biodiversity change.

Grass Growth in Response to Time of Rainfall and Season Along a Climate Gradient in Australian Rangelands

Percentage green leaf and height of the major perennial grass species was estimated fortnightly at six locations along a rainfall predictability gradient from Katherine (most predictable) to Lake Mere near Cobar (aseasonal), and regressed on estimated plant available soil moisture (PASM) and time of year (T). Green leaf is more strongly related to T at Katherine and to PASM at Lake Mere with the other sites in-between. Differences between species in terms of seasonal growth phenology were minor, at all sites, and there were no meaningful patterns in percentage contributions by the species to sward biomass. A strong inter-seasonal rainfall pattern over the period of the study may have masked phenological differences between species, but it is also possible that changes in species composition very soon after livestock were introduced resulted in a decline in phenological differentiation. Whatever the reason, the differences observed in this study would ~ot warrant their use in the formulation of management strategies.

Lens Design for the Near IR … Correction of Primary Chromatic Aberration

The dispersion characteristic of conventional optical glass types will vary as a function of the wavelength region being considered. In the 1.0 to 1.5 µm region, the dispersion of traditional crown and flint glass types is found to be nearly the same. This results in a unique condition when attempting a lens design solution for this spectral region. A typical example is described here that will be helpful in understanding this phenomenon.

Estimating secondary color

Image quality of a refracting lens system often will be limited by residual secondary color. Information in this paper permits rapid determination of blur spot size, and resulting image quality degradation, due to secondary color for a refracting lens system that has been designed with normal optical glasses and is free of primary color (achromatic). Included here is a brief description of the basic theory involved and an example of how the plotted data are used.

Rangelands and Global Change

The most important implications of this analysis for Australia's rangelands are: i) Better predictions of climate change, both in spatial resolution and degree of confidence, are needed to progress beyond a broad-scale analysis of possible effects. ii) Given that better projections of climate will become available, a "generic" rangelands model, incorporating a better understanding of system-level responses to changes in climate, atmospheric composition and management strategies, is needed to investigate the implications of global change. iii) Based on our current state of understanding, it seems as though the changes in Australia's rangelands will be within the capabilities of managers to cope, over at least the next several decades, provided they are made aware of the likely local and regional changes as predictions improve, and provided they adopt flexible management strategies.

Critical Issues for Understanding Global Change Effects on Terrestrial Ecosystems

Marked alterations in the Earth's environment have already been observed, and these presage even greater changes as the impact of human (i.e., land use and industrial) activities increases. Direct and indirect feedbacks link terrestrial ecosystems with global change, and include interactions affecting fluxes of water, energy, nutrients, and "greenhouse" gases and affecting ecosystem structure and composition. Community development can affect ecosystem dynamics by altering resource partitioning among biotic components and through changes in structural characteristics, thereby affecting feedbacks to global change. The response of terrestrial ecosystems to the climate-weather system is dependent on the spatial scale of the interactions between these systems and the temporal scale that links the various components. The International Geosphere-Biosphere Programme (IGBP), which was initiated by the International Council of Scientific Unions (ICSU) in 1986, has undertaken to develop a research plan to address a predictive understanding of how terrestrial ecosystem will be impacted by global changes in the environment and the potential feedbacks. The IGBP science plan, which incorporates established Core Projects and activities related to research on terrestrial ecosystem linkages to global change, includes the International Global Atmospheric Chemistry Project (IGAC); the Biospheric Aspects of the Hydrological Cycle (BAHC); the Global Change and Terrestrial Ecosystems (GCTE); Global Analysis, Integration, and Modelling (GAIM); IGBP Data and Information System (DIS); and IGBP Regional Research Centers (RRC). The coupling of research and policy communities for the purpose of developing mechanisms to adapt to these impending changes urgently needs to be established.