Antoinette M. Mannion

Domestication and the origins of agriculture: an appraisal

The first domestications of plants and animals, which occurred between 10 K years and 5 K years BP, and which underpinned the inception of agricultural systems, represent a major turning point in cultural and environmental history. Whilst much has been written on these topics, new archaeological discoveries and the development of new methods of data collection require that these issues should be reappraised. One example of a new archaeological discovery is that of evidence for rice cultivation prior to 10 K years BP in the middle Yangtze Basin of China. This region is now considered to be the likely centre of rice domestication and, because of the discovery of settlement structures, it may have been home to China’s oldest civilization. In addition, further age determination may establish this region of China as the earliest centre of agricultural innovation, instead of southwest Asia. New methods of age estimation, notably by radiocarbon, have necessitated a reappraisal of the origins of agriculture in Mesoamerica, whilst biomolecular techniques are contributing to the identification of the wild relatives of domesticated plants and animals. Genetic analysis has also been applied to modern human populations in order to establish the relationships between different groups and thus to attempt to determine the movement of peoples in prehistory. Such relationships in Europe have been related to the spread of agriculture from its centre of origin in southwest Asia, although this is speculative rather than conclusive. Despite these advances, however, there is still no unequivocal evidence as to why agriculture was initiated.

Biotechnology in agriculture: Agronomic and environmental considerations and reflections based on 15 years of GM crops

Genetically modified (GM) varieties of crops, notably soybean, maize, rape (canola) and cotton, were first grown commercially in 1996. In 2010 they occupied 148 million ha in 29 countries, mostly in the Americas and Asia but with an obvious absence in Europe where their introduction has been controversial due to concerns about environmental impairment and adverse impacts on human health. This paper reviews the published literature on the agronomic and environmental impact of GM crops in the last 15 years. Overall, the impact of GM crops has largely been agronomically and environmentally positive in both developed and developing world contexts. The often claimed negative impacts of GM crops have yet to materialize on large scales in the field. Agronomically, there have been yield increases per unit area, mainly due to reduced losses as a result of improved pest (i.e. insect) and weed control; in the case of conventional crops grown near GM varieties with insect resistance there have been benefits due to the so-called ‘halo’ effect. Environmentally, the decrease in insecticide use has benefited non-target and beneficial organisms while surface and groundwater contamination is less significant; human-health problems related to pesticide use have also declined. Equally important is the reduced carbon footprint as energy inputs are reduced. Of particular note, however, is the recognition that the success or longevity of GM crops is reliant on the speed with which resistance develops in target weeds and insects. However, resistance to GM-based plant resistance is already being detected in some pest populations and this suggests that scientists and farmers cannot be complacent. Current GM approaches are relatively transitory as a means of combating pests, as are conventional pesticides, and good management will determine how long this strategy proves positive. However, GM is a comparatively new science and the possibilities are considerable.

Can genetically modified cotton contribute to sustainable development in Africa

Genetically modified (GM) crops and sustainable development remain the foci of much media attention, especially given current concerns about a global food crisis. However, whilst the latter is embraced with enthusiasm by almost all groups, GM crops generate very mixed views. Some countries have welcomed GM, but others, notably those in Europe, adopt a cautious stance. This article aims to review the contribution that GM crops can make to agricultural sustainability in the developing world. Following brief reviews of both issues and their linkages, notably the pros and cons of GM cotton as a contributory factor in sustainability, a number of case studies from resourcepoor cotton farmers in Makhathini Flats, South Africa, is presented for a six-year period. Data on expenditure, productivity and income indicate that Bacillus thuringiensis (Bt) cotton is advantageous because it reduces costs, for example, of pesticides, and increases income, and the indications are that those benefits continued over at least the six years covered by the studies. There are repercussions of the additional income in the households; debts are reduced and money is invested in childrens education and in the farms. However, in the general GM debate, the results show that GM crops are not miracle products which alleviate poverty at a stroke, but nor is there evidence that they will cause the scale of environmental damage associated with indiscriminate pesticide use. Indeed, for some GM antagonists, perhaps even the majority, such debates are irrelevant – the transfer of genes between species is unnatural and unethical. For them, GM crops will never be acceptable despite the evidence and pressure to increase world food production.

Sustainable Development and Biotechnology

Sustainable development requires that resources are used as conservationally and as optimally as possible in order to maintain an adequate resource-base for future generations. It is not an easily-defined concept, nor is there any single way of achieving it. It does, however, focus on the environment, as this provides the resource-base that supports all society. Among the recently-evolved scientific developments, biotechnology has many applications that can improve resource-use. It involves the manipulation of organisms to undertake specific processes and includes genetic manipulation or ‘engineering’. In an environmental context, biotechnology has its greatest contribution to make in agriculture — especially by improving crop-yields. It offers opportunities to design crops for specific environments and to make crops more efficient producers of food-energy than otherwise. Biotechnology can thus manipulate primary energy-flows; it can also reduce fossil-fuel energy inputs into agricultural systems. It could also contribute to the mitigation of environmental problems such as deforestation and soil erosion. Both food- and fuel-energy resources are key components of sustainability. Sources produced biotechnologically, e.g. SCPs and biomass fuels, can supplement those produced conventionally. Resource recovery and recycling, and hazardous-waste disposal, are other environmentally-beneficial facets of biotechnology. These are equally pertinent to sustainable development because they extend the resource-base. In this context, biotechnology constitutes a vehicle for the improved manipulation of biogeochemical cycles. There are, however, potentially significant drawbacks in the use of biotechnology. These focus on technology transfer between the Developed and Developing World; this is economic and political, and relates to intellectual property rights, etc. Environmentally, the disadvantages concern the potential creation of ‘ecological ogres’ which could generate ecological disasters. Moreover, biotechnology relies heavily on the availability of a sustainable genepool, i.e. on biodiversity; indeed the two are interdependent. The high rates of extinction of plant and animal species that are currently occurring are thus limiting biotechnological opportunities for the future.

Diatoms: their use in physical geography

Diatoms are unicellular algae with a resistant siliceous outer shell or frustule which enables them to be preserved in marine and freshwater sediments. The frustules have distinct characteristics including shape and ornamentation upon which their taxonomy is based (Figure 1) and which, in the early days of research, was investigated using light microscopy. In recent years, however, considerable advances have been made using the electron microscope, especially the scanning electron microscope (e.g. Wornhardt, 1970; Haworth, 1975). Diatom frustules consist of two overlapping valves which are held together by girdling bands. Two major orders may be distinguished by their basic shape: the circular (Centrales) diatoms and the elongated (Pennales) diatoms (Figure 2). The Centrales are radially symmetrical and, with some exceptions in the genus Melosira, are mainly planktonic. The Pennales are bilaterally symmetrical and have been divided into suborders depending on the nature of the raphe (Figure 2),

Biodiversity, Biotechnology, and Business

Biotechnology is probably the only industry, except agriculture, wherein the relationship between biodiversity and the wealth that it generates is so explicit. Biodiversity is the variety of organisms, their genetic variation, and the variability of associations that these organisms display spatially. Biotechnology is the harnessing of living organisms and/or their components to undertake specific processes and/or generate useful products. The modern industry is a product of the 1980s and relies heavily on genetic manipulation (commonly referred to as ‘engineering’). It has many applications, the most important sectors being in medicine, agriculture, and the environment, where it can be involved in resource recovery, recycling, and pollution abatement.

Aquatic ecosystem development in Scotland: A review based on evidence from diatom assemblages

Abstract The importance of diatoms, unicellular microscopic algae, as functional components in aquatic ecosystems and as palaeoenvironmental indicators is described. The development of research involving diatoms in the examination of aquatic ecosystems in Scotland is considered in the context of descriptive studies, long‐term lake development since the retreat of Devensian ice, short‐term lake development in the last 200 years and Flandrian sea‐level changes. Research on modern diatom assemblages from Loch Leven, Kinross, is also discussed and the significance of recent work on problems of lake acidification in Galloway is examined in detail.