bluuebunny/crossref_metadata_2025_split huggingface dataset:
Changes in the Distribution of Aquatic Plants in a Tropical Swamp
Authors: Osborne Patrick L. , Leach Gregory J. 
Published: August 2009

Tropical wetlands are of great ecological importance and are worthy of widespread and vigorous conservation efforts. They are, however, very susceptible to environmental changes which often result from human activities. Waigani swamp near Port Moresby, Papua New Guinea, comprises a number of small, shallow lakes, the largest of which, Waigani Lake, has a surface area of 120 ha. This Lake now has nutrient-rich water with very high phytoplankton populations owing to sewage effluent disposal.Changes in the macrophyte flora and vegetation of Waigani Lake are documented in aerial photographs taken between 1942 and 1981. From 1942 to 1956 the Lake was dominated by emergent vegetation, and there was very little open water. Between 1956 and 1966 this emergent vegetation was replaced by dense stands of nymphaeids. In 1965, sewage disposal into Waigani Lake began and by 1974 only a few small stands of nymphaeids remained. By 1978 no nymphaeids could be found in Waigani Lake. The decline in the nymphaeid cover of Waigani Lake was accompanied by a regression of the surrounding reed-swamp. Two other lakes near Port Moresby are nutrient-poor and have a dominant and diverse macrophyte flora, being probably more comparable with Waigani Lake prior to its enrichment—apart from a recent takeover by a pestiferous free-floating water-fern.
In Absentia Benefits of Nature Preserves: A Review
Authors: Pearsall Samuel Haff 
Published: August 2009

Nature preserves are lands which are protected in order to provide hoped-for perpetuation of natural features within the context of a relatively unmodified natural environment. Nature preserves are typically justified on the basis of benefits to communities of plants or animals (biocentric benefits) or to Mankind (anthropocentric benefits). Anthropocentric benefits are usually described in terms of on-site uses of nature preserves for recreation, quiet enjoyment, scientific research, education, and/or resource-banking. These benefits are not, however, by any means the only effects which accrue to humans because of nature preserves; indeed some of them include the potential to damage the natural integrity of the preserves.The majority of benefits which accrue to humans from nature preserves are in absentia benefits, or benefits which do not require the presence of the beneficiaries on the site. In absentia benefits include residual benefits, or benefits which persist or develop after visiting a preserve, vicarious benefits, or benefits which exist for one or more people (or society) because of someone else's visit to a preserve, and non-use benefits, or benefits which exist for people without anyone necessarily having visited the preserve. In addition there are ecosystem services, maintaining vital gene-pools and natural nutrient and hydrological cycles, as the most important category of non-use benefits. Of these four categories of in absentia benefits, non-use benefits are, by far, the largest. Non-use benefits provide the majority of anthropocentric values accruing from nature preserves.
Towards Monitoring of Long-term Trends in Terrestrial Ecosystems
Authors: Hinds W. Ted 
Published: August 2009

Ecological monitoring is the purposeful observation, over time, of ecological processes in relation to stress. It differs from biological monitoring in that ecological monitoring does not consider the biota to be a surrogate filter to be analysed for contaminants, but rather has changes in the biotic processes as its focal point for observation of response to stress. Ecological monitoring methods aimed at detecting subtle or slow changes in ecological structure or function usually cannot be based on simple repetition of an arbitrarily chosen field measurement. An optimum method should be deliberately designed to be ecologically appropriate, statistically credible, and cost-efficient.Ecologically appropriate methods should consider the ecological processes that are most likely to respond to the stress of concern, so that relatively simple and well-defined measurements can be used. Statistical credibility requires that both Type I and Type II errors be addressed; Type I error (a false declaration of impact when none exists) and Type II error (a false declaration that no change has taken place or that an observed change is random) are about equally important in a monitoring context. Therefore, these error rates should probably be equal. Furthermore, the error rates should reflect the large inherent variability in undomesticated situations; the optimum may be 10%, rather than the traditional 5% or 1% for controlled experiments and observations.
An Experimental Approach to the Reclamation of a Limestone Quarry Floor: The First Three Years
Authors: Dixon Jean M. , Hambler David J. 
Published: August 2009

‘Three-inch [7.5 cm] crusher-run’ limestone proved entirely suitable as a substratum for the rapid establishment of pioneer vegetation on a quarry floor, but only with the addition of fertilizers. A manure derived from sewage and an NPK fertilizer mixture proved suitable additives. A grass variety (Festuca rubra var. fallax Hack.) was sown, and became established on the substratum treated with either additive. Immigrant mosses soon became dominant in a grass/moss community on the manured substratum, whilst F. rubra retained its ascendancy on the NPK-treated material. The moss-dominated community was not attractive to Rabbits, whereas the grass-dominated community proved attractive to these animals which are accepted as beneficial for conservation in this particular context.Further observations are required to assess (a) whether the by-passing of a cryptogamic stage in the prisere encouraged by the NPK mixture is a worthwhile objective, (b) whether the observed dominance of mosses encouraged by manure will be broken by F. rubra, and (c) whether the establishment of desirable immigrant species occurs differentially between the treatments. Meanwhile a perceptible degree of rehabilitation within three years may be claimed as a result of treatments producing a total plant cover of between 40% and 70%.
Nature Reserves, National Parks, and Post-war Reconstruction, in Britain
Authors: Sheail John 
Published: August 2009

An historical reconstruction of how key decisions were taken on Nature-conservation issues provides a context for appraising contemporary initiatives, both on a national and an international basis. This paper has been focused on one of the most important landmarks in the development of Nature conservation in Britain, namely the establishment of the Nature Conservancy in 1949. It recounts how the advocacy of pressure-groups, and the appointment of ad hoc inquiries, ensured that Nature conservation had a place in the Government's post-war reconstruction programme, and how it came to be regarded primarily as a scientific rather than a planning issue.There was nothing inevitable about the steps that were taken in the 1940s. They owed much to the way in which key personalities perceived shifts in public opinion towards the role of central government, and exploited the opportunities thrown up by the national parks movement. Despite the projection of the Nature Conservancy as a body that was modest in status and resources, its potential proved to be enormous. It had the responsibility not only for acquiring and managing Nature reserves, and for disseminating advice on wildlife conservation generally, but also for carrying out the research which was and always will be relevant to those functions. It is, however, doubtful whether the personnel who were responsible for the main initiatives in the 1940s fully appreciated the implications of what they were striving to achieve.
Complementarity Between Environment and Development Processes
Authors: Biswas Margaret R. , Biswas Asit K. 
Published: August 2009

Environmental consequences of economic growth and development became an area of major national concern primarily in industrialized countries during the nineteen-sixties. Undesirable side-effects of development became highly visible in terms of air, water, land, and noise, pollution, and people in such countries became concerned with the continuing environmental degradation and impacts on their health and life-style. The emphasis, however, was primarily on the physical environment.Two problems received much attention: the constantly increasing resource-use in the developed countries, and population explosion in the less-developed countries. Many doomsday scenarios were put forward, and there was a clamour for ‘no-growth’ in the West. This created much apprehension in the less-developed countries, because development was urgently needed to improve the living-standards of their citizens. Thus, ‘pollution of poverty’ became an important issue at the UN Conference on the Human Environment, which was held at Stockholm in 1972.
Man-induced Environmental Factors in Relation to Fertility Changes in Pinnipeds
Authors: Reijnders Peter J.H. 
Published: August 2009

The possible effects of human activities (such as the release of pollutants, exploitation, and disturbance) on the reproductive performance of pinniped populations (especially of certain seals) are discussed. While there are documented cases of reproductive rates increasing in exploited seal populations, the effects of disturbance on reproduction have only been suggested on the basis of rather incidental observations.In a number of cases the decline of a pinniped population has coincided with an elevation in the level of various contaminants. In some animals, reproductive failure has been associated with high levels of contaminants in their tissues; but even in these cases, no cause-and effect relation between pollutants and altered physiological processes has been established. Clearly, far more research will be needed to elucidate these problems.
Ecological Boundaries for Coral-reef Reserves: Principles and Guidelines
Authors: Salm Rodney V. 
Published: August 2009

As marine conservation activities intensify, planners and managers of protected areas are finding themselves with few guidelines or tools that are specific to the marine realm. Consequently the principles, criteria, and practices, of terrestrial protected areas tend to be transferred to the seas, where they are often inappropriate. In contrast to the situations with at all comparable sites on land, there is a sad shortage of published material on the application of ecological principles to the design and management of marine protected areas.Using the example of coral reefs, guidelines are presented here in the hope that they will elicit comment and stimulate the publication of similar guidelines for different marine environments.Coral-reef protected-area boundaries must fulfil two requirements: they must include appropriate coral-reef, confluent and neighbouring habitats, and a sufficient area of each. The first requirement defines the type, and the second the quantity, of habitats to be included in a protected area. Studies in the Chagos Archipelago, Indian Ocean, indicate that, there, the core zone of a protected coral-reef area should encompass 300 ha of diverse reef habitats if preservation of biotic diversity is the principal objective. The buffer-zone size needed will vary according to activities planned within the area, the extent of neighbouring coastal habitats, and the proximity of up-current or otherwise ‘linked’ sources of potential contamination.
India's Silent Valley and Its Threatened Rain-forest Ecosystems
Authors: Singh J.S. , Singh S.P. , Saxena A.K. , Rawat Y.S. 
Published: August 2009

Most of the features that are commonly attributed to typical tropical rain-forests, such as a preponderance of woody vegetation and species with leaves in the mesophyll size-class, tall slender trees with ‘flying buttress’ and unusually thin bark, multilayering of vegetation with abundance of epiphytes and stranglers, evergreenness, strong tendency to change in species composition in time and space, and high diversity of dominance, are plentifully displayed by the forests of the Silent Valley in southwestern India. A relatively high species-richness, remarkably thin bark of trees, and high total tree-basal area, indicate that the valley embodies a virgin forest and that conditions for growth are very favourable. Because of the terrain, heterogeneity in habitats is well marked.The proposed construction of a dam and large flooding reservoir threatens to bring about several undesirable alterations in the environment of the Silent Valley rain- and riparian forests, and the disturbances that would follow such construction and flooding would be highly detrimental to the diversity of the forests and to the complexity of their structure. Hence a plea is made for the setting aside forthwith of a proposed major ‘Silent Valley Biosphere Reserve’, which could safeguard a unique part of the world's genetical heritage and one of its most interesting complexes of natural ecosystems.
The Origin, Evolution, and Status, of the International Society for Environmental Education (ISEE)
Authors: Baldwin John H. , Sacks Arthur B. 
Published: August 2009

The International Society For Environmental Education was created in October 1983 to promote education for ecologically sustainable development in all nations of the world. The organization has ratified a constitution and by-laws, and the first full election of its Board of Directors, President, and Vice-President, will be held in February and March of 1985. The ISEE has already sponsored two international workshops, the first in New Delhi, India, and the second at Chateau Lake Louise, Canada. Three additional workshops are planned in Central America, Eastern Europe, and sub-Saharan Africa. WCB-ISEE will publish a quarterly international Newsletter, the first issue of which was scheduled to be released in December 1984. The next meeting of the officers and Board of ISEE will be in March of 1985 in New Delhi, India.Educators and environmental professionals are encouraged to join ISEE and become actively involved in developing its programme and participating in its governance. Those who wish to become involved should contact: Dr Craig B. Davis, Secretary-General of WCBISEE, School of Natural Resources, 2021 Coffey Road, Ohio State University, Columbus, Ohio 43210, USA.
Application of a Model of Ecological Succession to Conservation and Land-use Management
Authors: Rosenberg Diane B. , Freedman Stephen M. 
Published: August 2009

Ecological succession theory can be used in land-use planning to develop self-maintaining systems that meet conservation needs. This paper presents a management succession model and outlines methods that can be applied to regional land-use, rangeland, and agro-ecosystem, management. Traditionally, succession has been viewed as a repeatable and deterministic change in an ecosystem. Unlike the traditional view, the management succession model suggests that the successional process can be regulated to develop management designed communities. The model is based on current succession theory and consists of five steps; designed disturbance, selective colonization, inhibitory persistence, removal, and regeneration. Through the steps of the model, community interactions, life-history characteristics, and those abiotic factors that are to some extent controllable, are manipulated. The objective in manipulating these factors is to regulate successional sequences and rates of species replacement.To implement these steps a management practice, such as burning, can be used as a designed disturbance. The timing, intensity, and extent, of burning are regulated to insure that ‘selected colonizers’ become established. The design of the disturbance, and the selection of species and proportions of colonizers, is based upon the type of community structure that is wanted. Often a stable, persisting community is the goal. How long a community persists can be controlled by planned removal, which deliberately interrupts a successional sequence. The removal process can, in itself, be considered a type of disturbance, and can be used to regulate subsequent successional sequences and rates of replacement. In some instances a regenerating community is the goal, and management efforts can be adjusted to prevent successional sequences from occurring.
The Search for Global CO2 etc. ‘Greenhouse Effects’
Authors: Idso Sherwood B. 
Published: August 2009

The concentration of carbon dioxide (CO2) in Earth's atmosphere has been steadily increasing since the inception of the Industrial Revolution. Believed to be due primarily to the burning of fossil fuels and the clearing of forests, this phenomenon has two potential consequences of global importance.Many scientists believe that the CO2 increases projected for Earth's atmosphere by the middle of the next century will lead to a significant warming of the planet which could severely impact world agriculture and cause a melting of polar ice which would greatly raise sea-levels and lead to the flooding of coastal lowlands. Others, however, point to the demonstrable positive effects of elevated concentrations of atmospheric CO2 on plant productivity and wateruse efficiency, suggesting that more CO2 in the air will be beneficial to The Biosphere. Against this backlog of controversy, scientists of both persuasions have attempted the ‘first detection’ of either or both of these effects on a global scale.With respect to the quest for a climatic ‘signal’, numerous studies conducted to date have come up emptyhanded; it is just not discernible from the natural variations inherent in the data. However, there does appear to be a manifestation of enhanced global photosynthetic activity in the yearly amplitude of atmospheric CO2 concentrations at a number of sites around the world; and the most logical explanation of that seems to be the CO2-induced enhancement of plant growth and development which has been demonstrated to occur in hundreds of laboratory and field experiments.
Man and Nature on Rodrigues: Tragedy of an Island Common
Authors: Gade Daniel W. 
Published: August 2009

One of the most isolated islands on Earth, Rodrigues in the Indian Ocean stands as a modern-day ‘morality play’ of the consequences of environmental abuse. This tiny piece of land on the fringe of the tropics, emerged as an island through volcanic action some 1.5 million years ago, and acquired its biota mainly by long-distance dispersal from the west. Rodrigues was not inhabited by any people until 1691, and since then has always been administered from Mauritius which lies 650 km to the west.Burning, browsing, and woodcutting, have almost completely removed the indigenous forest. Close to a third of the native plant species have disappeared, and another third are on the brink of extinction. Giant land-tortoises, sea-turtles, and the Dugong, have vanished. Only two of the ten native species of land-birds survive. The endemic Solitaire was killed off even before the human population started to grow. Forest removal opened new habitats for introduced plants and animals, some of which are now highly invasive pests.Human impact on Rodrigues has gone beyond biotic effects. Cultivation of row-crops on the hilly terrain, and the keeping of domesticated animals in excessive numbers, led to the loss of most of the topsoil by the beginning of the twentieth century. Soil removal and compaction drastically modified the hydrology of the island, and silt deposition in the lagoon has contributed to fish decline. The inherent vulnerability of the native biota, the twin hazards of cyclones and droughts that befall the island, and demographic pressure, have all exacerbated the rate and degree of resource degradation.
Long-term Constraints on Human Activity
Authors: Lovins Amory B. 
Published: August 2009

Biophysical and other ‘outer limits’ of food, land, water, climatic change, stratospheric chemistry, energy, hazardous substances, non-fuel minerals, human stress, and social and ecological stability, raise fundamental questions about present trends in management methods and in global organization. The diverse outer limits surveyed in this paper reflect complex, poorly perceived, and often unsuspected, interconnections between numerous biological and geophysical processes, many of which are obscure or still unknown. Our lack of predictive power, let alone of quantitative understanding, implies a need to treat essential life-support systems with great caution and forbearance, lest we erode safety margins whose importance we do not yet appreciate.Even those outer limits which now seem remote are relevant to present policy, as their timely avoidance may require us to discard otherwise attractive short-term policies in favour of others that offer less immediate advantage but that retain options which may be needed later. Such alternative policies may have to rely more on social than on technical innovation in order to address underlying disequilibria rather than merely palliating their symptoms. Moreover, some outer limits are sufficiently imminent, or require such long lead-times to avoid, that fundamental changes in policy, in institutions, and in the degree of global interdependence, seem necessary if we are to live to enjoy some of the later and more interesting limits to human activity.
Solar Photothermal Power Generation
Authors: Meinel Aden Baker , Meinel Marjorie Pettit 
Published: August 2009

Solar energy could be a major resource for the semiarid regions of the United States and the world. This source of energy is a popular topic in the media at this time, but is it really the option which many would like to see or is it more likely to remain the illusion it has been up to now? Many ways of using solar energy have been proposed, and each appears to have a good technological basis. The additional factors that will see many solar schemes fall by the wayside are the hard facts of economics and the realities of social assimilation of technological advances.The major options of house-heating and cooling and electrical power production need to be examined. Home uses depend upon the degree to which people are willing to put up with the inconveniences associated with bulky roof-top units. It is more likely that solar energy will subsequently find wider acceptance when it can be converted into power and transportable fuels at remote solar power-farms located in the arid regions of the United States and other lands that are fortunate enough to have these sunny regions. The savings to the environment could be very considerable.
Tourism and Environmental Conservation: Conflict, Coexistence, or Symbiosis?
Authors: Budowski Gerardo 
Published: August 2009

A new and promising field has appeared as a result of the increased tourist industry based on natural resources, though too often such expansion has been achieved without due planning and has taken many people by surprise. Conservationists and their organizations have often reacted adversely to this ‘invasion’, but this need not be so. There are many reasons and examples which prove that a change of attitude, leading to a symbiotic relationship between tourism and conservation in the wide sense, can offer a very large variety of advantages and benefits—physical, cultural, ethical, and economic—to a country.A tourist industry can expect a brilliant future, based on natural assets of the environment, provided due consideration is given to the ecological principles which must guide resource-use. The alliance of those responsible for tourism with ecologists and conservationists is a natural one, that should contribute greatly to development—the right kind of development involving the right kind of change—leading to a better quality of life for all concerned.