Basics of Earth's Viability

Here we provide access to relevant theoretical background explaining basic concepts.

Ecosystem Health

Harwell, M. A., Gentile, J. H., McKinney, L. D., Tunnell, J. W., Jr, Dennison, W. C., Kelsey, R. H., Stanzel, K. M., Stunz, G. W., Withers, K. and Tunnell, J., 2019. Conceptual Framework for Assessing Ecosystem Health. Integr. Environ. Assess. Manag., 15, 544-564. 10.1002/ieam.4152:

Abstract: Over the past century, the environment of the Gulf of Mexico has been significantly altered and impaired by extensive human activities. A national commitment to restore the Gulf was finally initiated in response to the unprecedented Deepwater Horizon oil spill in 2010. Consequently, there is a critical need for an assessment framework and associated set of indicators that can characterize the health and sustainability of an ecosystem having the scale and complexity of the Gulf. The assessment framework presented here was developed as an integration of previous ecological risk– and environmental management–based frameworks for assessing ecosystem health. It was designed to identify the natural and anthropogenic drivers, pressures, and stressors impinging on ecosystems and ecosystem services, and the ecological conditions that result, manifested as effects on valued ecosystem components. Four types of societal and ecological responses are identified: reduction of pressures and stressors, remediation of existing stressors, active ecosystem restoration, and natural ecological recovery. From this conceptual framework are derived the specific indicators to characterize ecological condition and progress toward achieving defined ecological health and sustainability goals. Additionally, the framework incorporates a hierarchical structure to communicate results to a diversity of audiences, from research scientists to environmental managers and decision makers, with the level of detail or aggregation appropriate for each targeted audience. Two proof-of-concept studies were conducted to test this integrated assessment and decision framework, a prototype Texas Coastal Ecosystems Report Card, and a pilot study on enhancing rookery islands in the Mission-Aransas Reserve, Texas, USA. This Drivers–Pressures–Stressors–Condition–Responses (DPSCR4) conceptual framework is a comprehensive conceptual model of the coupled human–ecological system. Much like its predecessor, the ecological risk assessment framework, the DPSCR4 conceptual framework can be tailored to different scales of complexity, different ecosystem types with different stress regimes, and different environmental settings.

Lu, Y., R. Wang, Y. Zhang, H. Su, P. Wang, A. Jenkins, R. C. Ferrier, M. Bailey, and G. Squire. 2015. Ecosystem health towards sustainability. Ecosystem Health and Sustainability, 10.1890/EHS14-0013.1:

Abstract: Ecosystems are becoming damaged or degraded as a result of stresses especially associated with human activities. A healthy ecosystem is essential to provide the services that humans and the natural environment require and has tremendous social and economic value. Exploration of the definition of ecosystem health includes what constitutes health and what it means to be healthy. To evaluate ecosystem health, it is necessary to quantify ecosystem conditions using a variety of indicators. In this paper, the main principles and criteria for indicator selection, classification of indicators for different kinds of ecosystems, the most appropriate indicators for measuring ecosystem sustainability, and various methods and models for the assessment of ecosystem health are presented. Drivers, sustainability, and resilience are considered to be critical factors for ecosystem health and its assessment. Effective integration of ecological understanding with socioeconomic, biophysical, biogeochemical, and public‐policy dimensions is still the primary challenge in this field, and devising workable strategies to achieve and maintain ecosystem health is a key future challenge.

Marine Ecosystem Health: The University of Washington provides access to a wide range of publication addressing many aspects of marine ecosystem health.

Ecosystem Health:
A Student Page introducing the main concepts in an easy-to-understand language.

Ecosystem Indicators

Rowland, J. A., Bland, L. M., Keith, D. A., et al., 2019. Ecosystem indices to supportglobal biodiversity conservation. Conservation Letters, 10.1111/conl.12680:

Abstract: Governments have committed to global targets to slow biodiversity loss and sustainecosystem services. Biodiversity state indicators that measure progress toward thesetargets mostly focus on species, while indicators synthesizing ecosystem change arelargely lacking. We fill this gap with three indices quantifying past and projectedchanges in ecosystems using data from the International Union for Conservationof Nature (IUCN) Red List of Ecosystems. Our indices quantify changes in risk ofecosystem collapse, ecosystem area and ecological processes, and capture variationin underlying patterns among ecosystems. We apply the indices to three case studiesof regional and national assessments (American/Caribbean forests, terrestrial ecosys-tems of Colombia, and terrestrial ecosystems of South Africa) to illustrate the indices’complementarity and versatility in revealing patterns of interest for users across sec-tors. Our indices have the potential to fill the recognized need for ecosystem indicatorsto inform conservation targets, guide policy, and prioritize management actions.

Flint, N., Rolfe, J., Jones, C. E., Sellens, C., Johnston, N. D., Ukkola, L., 2017. An Ecosystem Health Index for a large and variable river basin: Methodology, challenges and continuous improvement in Queensland’s Fitzroy Basin, Ecological Indicators, 73, 626-636, 10.1016/j.ecolind.2016.10.007.

Abstract: Report cards are an increasingly popular method for summarising and communicating relative environmental performance and ecosystem health, including in aquatic environments. They are usually underpinned by an Ecosystem Health Index (EHI) that combines various individual indicators to produce an overall ecosystem health “score”. As a result of public water quality concerns, an integrated means of monitoring and reporting on aquatic ecosystem health was needed for the Fitzroy Basin in central Queensland, Australia. The Fitzroy Partnership for River Health was formed to address this need, and developed an EHI and report card for the Basin using existing monitoring data collected from various third parties including regulated companies operations and government. At 142,000 square kilometres, the Fitzroy Basin is the largest catchment draining to the World Heritage Listed Great Barrier Reef. The Fitzroy Basin provides an example of how to deliver an effective aquatic ecosystem health reporting system in a large and complex river basin. We describe the methodology used to develop an adaptive EHI for the Fitzroy Basin that addresses variability, complexity and scale issues associated with reporting across large areas. As well, we report how to manage the design and reporting stages given limitations in data collection and scientific understanding.

Burkhard, B., Müller, F., Lill, A., 2008. Ecosystem Health Indicators, In Jørgensen, S. E., Fath, B. D.: Encyclopedia of Ecology, Academic Press, pages 1132-1138:
This publication discusses the concept of ecosystem health and a set of possible indicators.

Abstract: Ecosystem health is a concept that integrates environmental conditions with the impacts of anthropogenic activities in order to give information for a sustainable use and management of natural resources. Therefore, related indicators have to reflect these anthropogenic impacts to represent the complex cause and effect relations in human–environmental systems. In comparison to the human health concept, different kinds of indicators for the assessment of various conditions and trends are available. In general, health means the absence of diseases, a good state, and the well-functioning of a system. As a physician uses general indices as temperature, blood pressure, or redness to assess human health, such general attributes like land cover, species abundance, or water body conditions can be found in ecosystems also. For more detailed investigations, specific indicators are available related to certain topics or different parts of the system. For holistic assessments, indicator sets that combine different features have to be used, as a physician combines different parameters for his final diagnosis. With regard to the special characteristics of ecosystems, their spatial heterogeneity, multilevel phenomena, and multiple variables of interest at multiple timescales have to be taken into account. Different concepts of indicator derivation and exemplary sets of indicators are presented within the text. The focal categories are: indicators based on the abundance of selected species, indicators based on the concentration of selected elements, indicators based on ratios between different classes of organisms or elements, indicators based on ecological strategies or processes, indicators based on ecosystem composition and structure and systems theoretical holistic indicators. However, the application of indicators on appropriate temporal and spatial scales can be restricted by limited data availability. Therefore, surrogates or suboptimal parameters for the quantification of indicators have to be used often. With regard to environmental management, decision makers’ actions are required if the ecosystem health indicators reach undesirable levels in order to restore preferred conditions and the functions of the respective ecosystem.

Xu, F.-L., Zhao, Z.-Y., Zhana, W., Zhao, S.-S., Dawson, R. W., Tao, S., 2005. An ecosystem health index methodology (EHIM) for lake ecosystem health assessment. Ecological Modelling, 188(2-4), 327-339, 10.1016/j.ecolmodel.2005.01.058:

Abstract: An ecosystem health index methodology (EHIM) was developed for assessing lake ecosystem health. A scale from 0 to 100 was chosen as a basis for ranking where an ecosystem health index (EHI) of zero indicates the worst possible health state and one of 100 the best possible health state. There are five necessary steps in the EHIM: (l) to select basic and additional indicators; (2) to calculate sub-EHIs for all selected indicators; (3) to determine weighting factors for all selected indicators; (4) to calculate a synthetic EHI using the sub-EHIs and weighting factors for all selected indicators; (5) to assess ecosystem health based on synthetic EHI values. The EHIM was successfully applied to a series of Italian lakes for assessment and comparison purposes. Phytoplankton biomass (BA) was selected to serve as a basic indicator, while zooplankton biomass (BZ), the ratio of BZ to BA (BZ/BA), and exergy and structural exergy were used as additional indicators. The results suggest that the EHIM is a valuable relatively uncomplicated methodology with simple principles, ease of calculation, reliable and intuitive results. As a practical planning tool, it can be widely used for the quantitative assessment and comparison of ecosystem health states for a single lake, a series of different lakes, or more complicated lake systems.

Ecosystem health report cards — An approach to integrated assessment: This poster by Thomas et al. provides an overview of the conceptual framework for ecosystem health report cards used in a case study in Maryland, USA.

Explore ecosystem health indicators:
An introductory page compiled by Scotland's environment, a part of government of Scotland. The page gives access to deatils on many environmental indicators. See also Ecosystem health indicators.

Forest Health

Forest and Ecosystem Health: The Aspen for Environmental Studies provides information on forest health projects and indicators.

Xiao, F., Ouyang, H., Zhang, Q. et al., 2004. Forest ecosystem health assessment and analysis in China. J. Geogr. Sci., 14, 18–24. 10.1007/BF02873086:

Abstract: Based on more than 300 forest sample plots surveying data and forestry statistical data, remote sensing information from the NOAA AVHRR database and the daily meteorological data of 300 stations, we selected vigor, organization and resilience as the indicators to assess large-scale forest ecosystem health in China and analyzed the spatial pattern of forest ecosystem health and influencing factors. The results of assessment indicated that the spatial pattern of forest ecosystem health showed a decreasing trend along latitude gradients and longitude gradients. The healthy forests are mainly distributed in natural forests, tropical rainforests and seasonal rainforests; secondarily orderly in northeast national forest zone, subtropical forest zonation and southwest forest zonation; while the unhealthy forests were mainly located in warm temperate zone and Xinjiang-Mongolia forest zone. The coefficient of correction between Forest ecosystem Health Index (FEHI) and annual average precipitation was 0.58 (p<0.01), while the coefficient of correlation between FEHI and annual mean temperatures was 0.49 (p<0.01), which identified that the precipitation and temperatures affect the pattern of FEHI, and the precipitation’s effect was stronger than the temperature’. We also measured the correlation coefficient between FEHI and NPP, biodiversity and resistance, which were 0.64, 0.76 and 0.81 (p<0.01) respectively. The order of effect on forest ecosystem health was vigor, organization and resistance.

Ecosystem Services

Earth Observations: Satellite Imagery telling the State of the Planet

Conservation’s Eyes in the Sky:
An interview with John Amos, the founder of SkyTruth. See also SkyTruth on Twitter.