Environmental distress syndrome

When the natural environment is subject to multiple stresses, it can exhibit distress symptoms.  The term ‘environmental distress syndrome’ refers to deteriorating environmental conditions and concomitant threats to human health.  In other words environmental distress syndrome is a condition that affected the human beings of the earth after years of pollution and exploitation of the planet. A distress syndrome refers to the irreversible processes of system breakdown leading to the termination of the system before its normal lifespan. An ecological system should be healthy and free from ‘distress syndrome’. Healthy ecological systems are an essential condition of healthy people, healthy communities and sustainable livelihoods.

Pollution, the introduction of contaminants into an environment that causes instability, disorder, harm or discomfort to the physical ecosystem or living organisms.

Paul Epstein (1997) of Harvard University’s centre for health and global environment lists 5 symptoms of environmental distress syndrome.

1.    The re-emergence of infectious diseases e.g., cholera, typhoid, dengue fever, drug-resistant tuberculosis.

2.    Loss of biodiversity e.g., decline of frogs in 140 countries from 6 continents.

3.    The growing dominance of generalist species –e.g., crows, Canada geese.

4.    The decline in pollinators e.g., bees, birds, bats, butterflies, beetles.

5.    The proliferation of harmful algal blooms e.g., paralytic shellfish poisoning.

Stress from human activity is a major factor in transforming healthy ecological systems to sick systems. The complex interaction of population, technology and human behaviour has resulted in anthropogenic stress on most of the world’s ecological systems (population-pollution syndrome).

Environmental stress

Environmental stress can be either natural or anthropogenic (i.e., resulting from human actions). Many natural environmental stresses such as hurricanes, droughts, floods, earthquakes and forest fires are a periodic feature of earth. But anthropogenic environmental stress includes the production and release of chemical compounds and large scale land-use changes result directly from human actions. The population explosion, agricultural expansion and industrial revolution greatly enhanced the anthropogenic stress on the environment. The intensities of ecological stresses vary in space and time. When the ecosystem is subjected to a chronic stress exceeding its tolerance limit, the ecosystem may display a syndrome of disruptions of its structure and function. The structural changes include biotic impoverishment with a reduction in size, number and abundance of organisms. The functional changes include gross community metabolism, efficiency of mineral cycles and changes in the energy flow rates.The stress in aquatic ecosystems is best exemplified by eutrophication (forced nutrient  enrichment), Increased primary production with algal blooms and insufficient decomposition of organic matter with increased anaerobic zones. There is a replacement of longer lived larger species by short – lived opportunistic species.

Progression of global environmental stress

All environmental changes progress at two levels:

Systemic global changes refer to changes operating at the global scale. For example, the doubling of carbon dioxide from more fossil fuels leads to enhanced greenhouse effect which leads to global climatic changes.

Cumulative global changes refer to the snowballing effect of local changes which add up to produce change on a global scale. E.g., acid rain or soil erosion.

An ecological system is healthy and free from ‘distress syndrome’ if it is stable and sustainable that is if it is active and maintains its organization and autonomy over time and is resilient to stress (Costanza, 1992).

Costanza’s concept (1992) of ecosystem health indicators

Costanza proposed 6 attributes of ecosystem health indicators.

1.    Homeostasis (self – regulation) 2. Absence of disease 3. Diversity or complexity (number and types of species) 4.stability or resilience 5. Vigour or scope for system growth and 6. Balance between system components.

Xu and Mage (2001) proposed 4 sets of criteria to assess ecosystem health: structural changes, functional changes, organizational changes and dynamics.

"The earth is what we all have in common."- Wendell Berry.
"In nature nothing exists alone." -Rachel Carson, Silent spring.