Disease as a Stabilizing Factor in the Protection of Landscape: The Leishmaniases as Models

It is suggested that disease limits populations only under exceptional circumstances, when other population-limiting factors are inoperative. This is precisely the situation with human populations, which have grown well (perhaps as much as three logs) beyond sustainability. It is inconceivable that any self-regulatory mechanism will bring human populations down to a level compatible with the survival of other large mammals, so the only hope for environmental survival is disease. In this essay, I discuss the inexorable rise of human populations and our seeming escape from all normal boundaries to population growth, apart, perhaps, from diseases. I then provide examples of how the various leishmaniases have affected and constrained human populations, or have failed to do so, providing an example of how diseases may ultimately protect landscapes from anthropogenic change.     

Ecological science and tomorrow's world

Beginning with an outline of uncertainties about the number of species on Earth today, this paper addresses likely causes and consequences of the manifest acceleration in extinction rates over the past few centuries. The ultimate causes are habitat destruction, alien introductions, overexploitation and climate change. Increases in human numbers and per capita impacts underlie all of these. Against a background review of these factors, I conclude with a discussion of the policy implications for equitably proportionate actions—and of the difficulties in achieving them.     

Assessment of mite fauna in different coffee cropping systems in Brazil

Agro-ecological diversification may increase natural biodiversity and decrease environmental impacts caused by the intensification of management practices, especially with respect to pest control. This study aimed to evaluate mite populations from surveys in commercial coffee (Coffea arabica) orchards managed in different ways. Four different cropping systems were compared: a conventional system (CS), non-pesticide system (NPS), organic system (OS) and organic agroforestry system (OAS). Mite samples were taken from 24 coffee plantations (n?=?6 for each management strategy). Six leaves per plant were collected from five sampling sites totalling 30 leaves from each plantation. Mites were removed from individual leaves, counted and identified to family level. Amongst the predatory mites, two families were detected; the Phytoseiidae was the most abundant family while the Stigmaeidae, generalist predatory mites, were only found in two management systems (NPS and AOS). Of the two families of phytophagous mites, the family Tenuipalpidae was the most abundant, but rarely found in AOS. The other phytophagous family, Tetranychidae, was less abundant in coffee crops than Tenuipalpidae, but the most abundant phytophagous family in CS. Understanding the relationship between mite populations and management practices can aid in choice of spraying strategies for different coffee management systems.     

Population ageing: what should we worry about?

Approximately half the world''s population now has replacement-level fertility or below. The UK experience in accommodating to a changing dependency ratio provides some generalizable insights. A mechanistic approach assuming a fixed retirement age and a need to raise fertility or increase immigration in order to maintain pensions at a fixed proportion of the gross domestic product (GDP) is overstated and wrong. It needs to be replaced by a welfare optimizing model, which takes into account the increasing years of healthy life, a slow rise in the pensionable age, capital inheritance and wider welfare considerations of population density that are not reflected in GDP measures. A combined replacement ratio (CRR) is suggested for developed countries combining the impact of the fertility rate and immigration rate. A CRR above 2 implies continued population growth. The current UK CRR of 2.48 is higher than needed for pension reasons, and it is suggested that it exceeds the welfare maximizing level.     

Uncertainty, ecology, sustainability and policy

Using an Australian focus to explore theoretical and policy issues of wider concern, this article examines linkages between public policy and the science of ecology. This is done within the broader framework of sustainability, emphasizing the problem of decision making in the face of uncertainty. Insights from the ecological, risk, sustainability and policy literatures are used. The sustainability-uncertainty problem is characterized, and the adequacy of existing policy support techniques and approaches noted, particularly the precautionary principle. The problem is further defined using the notion of ignorance. The treatment of ignorance and uncertainty in ecology is discussed. We suggest that the science of ecology has had a limited influence on policy formulation and discuss the basis of this using biodiversity conservation and ecosystem management as examples. We conclude by considering challenges for handling risk, uncertainty and ignorance in ecological science for policy formulation. We emphasize the need for improved communication between the science and policy communities, greater recognition of the limits of quantitative techniques in addressing uncertainty, and contingency planning.     

Protected areas — protected from a greater ‘what’?

Natural environments are assailed on every side through the unprecedentedly rapid expansion of human activities. In the absence of conservation responses of a scope and scale to match the challenge, we shall shortly witness the widespread degradation and destruction of many wildlands and their biotas. Fortunately we still have time, though only just time, to slow and stem the biotic holocaust overtaking the biosphere. But the traditional measures, notably in the form of protected areas, are becoming ever-more limited in their capacity to resist. While we need many more protected areas — better protected too — we shall find there is a much more positive payoff in tackling the tide of environmentally impoverishing human activities, principally through initiatives directed at sustainable development of all environments and all their communities, both human and non-human.     

Japan and the concept of sustainability

This article describes a sustainable human social adaptation. It provides an example of how a human population responds to environmental stresses and modulates its population given technological abilities for food production and population control. The example used is Japan over the past 500 years. The concept of “sustainability” has become a popular concept used in a variety of conflicting and contradictory contexts and with resulting confusion. This eassay is offered as a point of discussion to produce more precise definitions of the concept of sustainability as it applies to human society.     

Can Biospecimen Science Expedite the Ex Situ Conservation of Plants in Megadiverse Countries? A Focus on the Flora of Brazil

Increasing the number of species conserved ex situ in Megadiverse countries is a major task exacerbated by many intricate factors including: biome complexity, wide range of biodiversity and an incomplete knowledge of life cycles, reproductive strategies, adaptations and species interactions. Although, establishing safe reserves is a crucial conservation measure their security and effective maintenance can be unfavourably compromised by climate change and the risks incurred by socioeconomic instability and changes in land use. Anthropogenic impacts, non-sustainable practices and habitat erosion have motivated current international efforts which focused on Brazil as host of ‘Rio+20’ the United Nation's twentieth anniversary conference on sustainable development. The revised targets of the Global Strategy for Plant Conservation (GSPC) are responses to species decline and realizing Target 8, which concerns ex situ conservation, places the heaviest burdens on countries that are custodians of the highest levels of global biodiversity. At the scientific level, ex situ conservation of endemic species in genebanks is often hindered by a lack of information about molecular genetics and problematic (recalcitrant) storage behaviors that restrict the preservation of flora native to Megadiverse countries. The potential for applying the ‘Biospecimen Science’ paradigm in expediting conservation in biodiversity-rich biomes is considered using Brazil as an exemplar of a Megadiverse country. The impacts of process chains on the quality of preserved plant germplasm and using evidence-based research to improve conservation outcomes, risk and quality management systems are appraised. The Biospecimen Science approach is not intended to displace conventional conservation practices but rather, to enhance their effectiveness in terms of the scale and efficiency of their scientific and technical operations.     

How natural is a nature reserve?: an ideological study of British nature conservation landscapes

Areas set apart for nature conservation in Britain are broadly categorised according to their cultural purpose, and names are assigned to these in this paper. Nature reserves may be similar to zoos and botanic gardens in aiming to maintain the diversity of species and if so are termed biodiversity reserves. This tradition understands nature as a static collection of entities apart from humans. Maintaining traditional management at a site is arguably a good way to sustain species, it also retains old ways in which humans and nature were integrated in the life of the nation and so are called historic countryside parks. There is growing interest in wilderness areas, where nature is seen as primarily processes protected from human interference. Despite the strength of each of these, they suffer from attempting to restrict nature to a ghetto, a process that is economically and environmentally costly. Companion places are places which set sustainable examples of integrating human life and economic activity with maintaining biodiversity and offering an opportunity to encounter wild processes at the heart of life. The language of these four types, or vectors, of nature reserves is offered to help the discussion of our place in nature.     

The Sun's Path

Keith, Lawrence H., ed. Identification and Analysis of Organic Pollutants in Water Ann Arbor, Michigan: Ann Arbor Science Publishers, Inc., 1976 707 pp., $27.50. Reviewed by E. Lawrence Bahn

Baldry, Peter The Battle against Bacteria: A Fresh Look New York: Cambridge University Press, 1976 172 pp., $9.95. Reviewed by Donald F. Logsdon

Palmer, Ralph S., ed. Handbook of North American Birds, Volume 2: Waterfowl (Part 1), Volume 3: Waterfowl (Part 2) New Haven: Yale University Press, 1976 521 and 560 pp., $30 each, $60 set. Reviewed by Karl L. Trever

Hurlbut, Cornelius Jr., ed. The Planet We Live On: An Illustrated Encyclopedia of the Earth Sciences New York: Harry N. Abrams, Inc., 1976 488 pp., $37.50. Reviewed by Joaquin Rodriguez

MacGillavry, Caroline H. Fantasy and Symmetry: The Periodic Drawings of M. C Escher New York: Harry N. Abrams, Inc., 1976 84 pp., $15.00 Reviewed by John G. Harvey

Perrins, Dr. Christopher Birds: Their Life, Their Ways, Their World New York: Harry N. Abrams, Inc., 1976 157 pp., $19.85. Reviewed by J. P. Kennedy

Hoyt, William Graves Lowell and Mars Tucson: The University of Arizona Press, 1976 376 pp., $8.50 paper, $13.95 cloth. Reviewed by Van E. Neie

Dagg, Anne Innis, and Foster, J. Bristol The Giraffe: Its Biology, Behavior, and Ecology New York: Van Nostrand Reinhold Co., 1976 115 pp., $13.95. Reviewed by Theodore W. Munch     

生态遗传学在生物多样性保护中的作用

本文就生态遗传学在生物多样性保护中的作用问题谈了几点看法。首先陈述了生态遗传学的性质,它是种群生态学和种群遗传学的结合,研究种群层次上正在进行着的进化;其次列举了生态遗传学的基本内容,说明生态遗传学是生物多样性研究和保护不可缺少的基本知识。最后举两个实例阐明生态遗传学在生物多样性保护中的具体应用。