Notes on Environment - Links

http://www.du.ac.in/fileadmin/DU/Academics/course_material/SE_01.pdf

Ecocline

An ecocline is a variation of the physicochemical environment dependent of one or two physico-chemical factors of life, and thus presence/absence of certain species. An ecocline can be a thermocline, chemocline (chemical gradient), halocline (salinity gradient) or pycnocline (variations in density of water induced by temperature or salinity).

An ecotone describes a variation in species prevalence and is often not strictly dependent a major physical factor separating an ecosystem from another, with resulting habitat variability. An ecotone is often unobtrusive and harder to measure.

An ecotone is often associated with an ecocline: a "physical transition zone" between two systems. The ecotone and ecocline concepts are sometimes confused: an ecocline can signal an ecotone chemically (ex: pH or salinity gradient), or microclimatically (hydrothermal gradient) between two ecosystems.

Law of tolerance

A law stating that the abundance or distribution of an organism can be controlled by certain factors (e.g. the climatic, topographic, and biological requirements of plants and animals) where levels of these exceed the maximum or minimum limits of tolerance of that organism.

For each factor that affects a population, the population displays a range of tolerance.

For an organism to be successful in any given environment, each factor that affects the organism must remain within its tolerance range for that organism.

If any factor exceeds the minimum or maximum tolerance of that organism, it will fail to thrive.

Ecological Equivalence

May be defined as 

Different species that occupies a similar ecological niche in a similar ecosystem in a different part of the world or may be said that it is the case in which two or more species have enough similarities so that any could replace the other in a specified habitat. 

For detail study these links are suggested

http://www.eianz.org/sitebuilder/aboutus/knowledge/asset/files/320/franksandrew.pdf

Acclimation

Acclimatization, or acclimation 

It is the process in which an individual organism adjusting to a gradual change in its environment, such as a change in temperature, humidity, photoperiod, or pH, allowing it to maintain performance across a range of environmental conditions. Acclimatization occurs in a short period of time from days to weeks, and within the organism's lifetime.  

This may be a discrete occurrence or may instead represent part of a periodic cycle, such as a mammal shedding heavy winter fur in favor of a lighter summer coat. Organisms can adjust their morphological, behavioral, physical, and/or biochemical traits in response to changes in their environment. While the capacity to acclimate to novel environments has been well documented in thousands of species, researchers still know very little about how and why organisms acclimate the way that they do.

Biochemical changes

In order to maintain performance across a range of environmental conditions, there are several strategies organisms use to acclimate. In response to changes in temperature, organisms can change the biochemistry of cell membranes making them more fluid in cold temperatures and less fluid in warm temperatures by increasing the number of membrane proteins. Organisms may also express specific proteins called heat shock proteins that may act as molecular chaperons and help the cell maintain function under periods of extreme stress. It has been shown, that organisms which are acclimated to high or low temperatures display relatively high resting levels of heat shock proteins so that when they are exposed to even more extreme temperatures the proteins are readily available. Expression of heat shock proteins and regulation of membrane fluidity are just two of many biochemical methods organisms use to acclimate to novel environments. Note: acclimation and acclimatization are two very different terms that are not interchangeable. Acclimation is used under laboratory conditions, while acclimatization is "in the field" or in nature.

Morphological

Organisms are able to change several characteristics relating to their morphology in order to maintain performance in novel environments. Examples may include changing of skin color or pattern to allow for efficient thermoregulation, or a change in body size of offspring as a result of low food levels in the ecosystem.

The degree to which organisms are able to acclimate is dictated by their phenotypic plasticity or the ability of an organism to change certain traits. Recent research in the study of acclimation capacity has focused more heavily on the evolution of phenotypic plasticity rather than acclimation responses. Scientists believe that when they understand more about how organisms evolved the capacity to acclimate, they will better understand acclimation.

Examples

Plants

Many plants, such as maple trees, irises, and tomatoes, can survive freezing temperatures if the temperature gradually drops lower and lower each night over a period of days or weeks. The same drop might kill them if it occurred suddenly. Studies have shown that tomato plants that were acclimated to higher temperature over several days were more efficient at photosynthesis at relatively high temperatures than were plants that were not allowed to acclimate.

Animals

Animals acclimatize in many ways. Sheep grow very thick wool in cold, damp climates. Fish are able to adjust only gradually to changes in water temperature and quality. Tropical fish sold at pet stores are often kept in acclimatization bags until this process is complete.

Concept of Species

Biological Species Concept

The biological species concept defines a species as members of populations that actually or potentially interbreed in nature, not according to similarity of appearance. Although appearance is helpful in identifying species, it does not define species.

• Species are groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups.

• A species is a reproductive community of populations (reproductively isolated from others) that occupies a specific niche in nature.

• Species are the members in aggregate of a group of populations that breed or potentially interbreed with each other under natural conditions.

Evolutionary species concept

• A species is a lineage (an ancestral-descendant sequence of populations) evolving separately from others and with its own unitary evolutionary roles and tendencies.
• A species is a single lineage of ancestor-descendant populations which maintain its identity from other such lineages and which has it own evolutionary tendencies and historical fate.
• A species is a population or group of populations that shares a common evolutionary fate through time .

For further study:

http://www.ucl.ac.uk/taxome/jim/Sp/species.pdf

Approaches to Corporate Ethics and Bio-ethics

In business, and most other types of organizations, the job of maintaining the values of the company is not the responsibility of any one department or individual; everyone—officers and board, executives, managers, supervisors, and individual contributors—has a role in fostering ethical behavior.  Each is a role model to others and can encourage and motivate fellow employees to "do the right thing."

Corporate ethics is a form of applied ethics or professional ethics that examines ethical principles and moral or ethical problems that arise in a business environment. It applies to all aspects of business conduct and is relevant to the conduct of individuals and entire organizations.

The range and quantity of business ethical issues reflects the interaction of profit-maximizing behavior with non-economic concerns. Interest in business ethics accelerated dramatically during the 1980s and 1990s, both within major corporations and within academia. For example, today most major corporations promote their commitment to non-economic values under headings such as ethics codes and social responsibility charters. 

Ethical issues include the rights and duties between a company and its employees, suppliers, customers and neighbors, its fiduciary (a legal or ethical relationship of trust between two or more parties. Typically, a fiduciary prudently takes care of money for another person.) responsibility to its shareholders. Issues concerning relations between different companies include hostile take-overs and industrial espionage. Related issues include corporate governance;corporate social entrepreneurship; political contributions.

Main tasks are:

• Governance: regulation, corporate governance committees, Sarbanes-Oxley, auditing, etc.
• Creating an Ethical Culture: strategic planning, human resources, organizational ethics, etc.
• Leadership: executive compensation, tone at the top, the role of the CEO in ethics, etc.
• Corporate Social Responsibility: sustainability, stakeholder theory, triple bottom line, etc.
• Workplace Issues: labor and employment practices, monitoring, work/life balance, etc.
• Product and Brand: consumer safety, reputation, intellectual property, and strategic marketing
• Corporate Wrongdoing: corruption, bribery, scandals, whistleblowing, etc.
• Professional Ethics: the behavior of managers and employees in matters such as loyalty, honesty, etc.
• Global Business Ethics: cross-cultural issues that arise in countries such as China and India.

Bioethics is the study of typically controversial ethics brought about by advances in biology and medicine. It is also moral discernment as it relates to medical policy, practice, and research. Bioethicists are concerned with the ethical questions that arise in the relationships among life sciences, biotechnology, medicine, politics, law, and philosophy. It also includes the study of the more commonplace questions of values ("the ethics of the ordinary") which arise in primary care and other branches of medicine.

The field of bioethics has addressed a broad swath of human inquiry, ranging from debates over the boundaries of life (e.g. abortion, euthanasia), surrogacy, the allocation of scarce health care resources (e.g. organ donation, health care rationing) to the right to refuse medical care for religious or cultural reasons. Bioethicists often disagree among themselves over the precise limits of their discipline, debating whether the field should concern itself with the ethical evaluation of all questions involving biology and medicine, or only a subset of these questions. Some bioethicists would narrow ethical evaluation only to the morality of medical treatments or technological innovations, and the timing of medical treatment of humans. Others would broaden the scope of ethical evaluation to include the morality of all actions that might help or harm organisms capable of feeling fear.

The scope of bioethics can expand with biotechnology, including cloning, gene therapy, life extension, human genetic engineering, astroethics and life in space, and manipulation of basic biology through altered DNA, XNA and proteins. These developments will affect future evolution, and may require new principles that address life at its core, such as biotic ethics that values life itself at its basic biological processes and structures, and seeks their propagation.