Mediterranean ecosystems rival tropical ecosystems in terms of plant biodiversity. The Mediterranean Basin (MB) itself hosts 25 000 plant species, half of which are endemic. This rich biodiversity and the complex biogeographical and political issues make conservation a difficult task in the region. Species, habitat, ecosystem and landscape approaches have been used to identify conservation targets at various scales: ie, European, national, regional and local. Conservation decisions require adequate information at the species, community and habitat level. Nevertheless and despite recent improvements/efforts, this information is still incomplete, fragmented and varies from one country to another. This paper reviews the biogeographic data, the problems arising from current conservation efforts and methods for the conservation assessment and prioritization using GIS. GIS has an important role to play for managing spatial and attribute information on the ecosystems of the MB and to facilitate interactions with existing databases. Where limited information is available it can be used for prediction when directly or indirectly linked to externally built models. As well as being a predictive tool today GIS incorporate spatial techniques which can improve the level of information such as fuzzy logic, geostatistics, or provide insight about landscape changes such as 3D visualization. Where there are limited resources it can assist with identifying sites of conservation priority or the resolution of environmental conflicts (scenario building). Although not a panacea, GIS is an invaluable tool for improving the understanding of Mediterranean ecosystems and their dynamics and for practical management in a region that is under increasing pressure from human impact.

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Aim The aim of this study was to explore the environmental factors that determine the spatial distribution of oro‐mediterranean and alti‐mediterranean plant communities in Crete. Location The paper provides a quantitative analysis of vegetation–environment relationships for two study areas within the Lefka Ori massif Crete, a proposed Natura 2000 site. Methods Eleven environmental variables were recorded: altitude, slope, aspect, percentage of bare rock, percentage of unvegetated ground, soil depth, pH, organic matter content and percentages of sand, silt and clay content. Classification of the vegetation was based on twinspan, while detrended correspondence analysis (DCA) and canonical correspondence analysis (CCA) were used to identify environmental gradients linked to community distribution. Results One hundred and twenty‐five species were recorded from 120 plots located within the two study areas. Forty‐seven of the recorded species are endemic, belonging to 35 families. Hemicryptophytes and chamaephytes were the most frequent, suggesting a typical oro‐mediterranean life form spectrum. The samples were classified into five main community types and one transitional. The main gradients, identified by CCA, were altitude and surface cover type in the North‐west site, while in the Central site the gradients were soil formation‐development and surface cover type. Main conclusions The use of classification in combination with ordination techniques resulted in a good discrimination between plant communities and a greater understanding of controlling environmental factors. The methodology adopted can be employed for improving baseline information on plant community ecology and distribution in Mediterranean mountain zones.

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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.

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 paper 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 resource-poor cotton farmers in Makhathini Flats, South Africa, is presented for a six year period. Data on expenditure, productivity and income indicate that Bt cotton is advantageous because it reduces costs, e.g. of pesticides, and increases income, and the indications are that those benefits continued over at least the six years cover by the studies. There are repercussions of the additional income in the households; debts are reduced and money is invested in children's 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 pressure to increase world food production.

Ever since it began 10,000 years ago, agriculture has been a major cause of land transformation. It has been the basis on which civilizations have waxed and waned, it has allowed the world population to reach 5 × 109 and it has profoundly influenced cultural and scientific development. While its inception was itself momentous in terms of environmental and cultural history, the changes in agriculture caused by the expansion of Europe between 1500 and 1900 had equally profound ramifications. These developments literally changed the face of the earth. This paper surveys the changes that have taken place so far, while Part 2, to appear in the next issue, looks at likely future patterns.

Hebridean sites of the coastal sand cliffs and associated machair, or sandy plain have been known for many years. Artefacts and ecofacts of various types have long been collected from archaeological sites in the eroding sand-cliffs of the machairs of the Outer Hebrides. Early in 1983, personnel of the then Central Excavation Unit of Historic Scotland's predecessor revisited very nearly all of the coastal archaeological sites then known in the Long Isle, with the specific task of identifying those at immediate threat from coastal erosion and of assessing the feasibility of their excavation or preservation. Some 32 sites were seen to be undergoing active erosion; at nine of them preservation was not being pursued and excavation was feasible. These sites were of two morphotypes: sites exposed in roughly vertical sand-cliffs and sites exposed over relatively large horzontal areas of sand deflation. It was decided to examine one sand-cliff site along its exposed face. The site selected was Balelone in North Uist, its excavation designed to explore both the problems associated with the excavation of deep midden sites with complex stratigraphy and the not-inconsiderable problems of excavation in sand. In the light of the Balelone trial excavation, a new approach was called for. A structured approach aimed firstly at establishing the three-dimensional extent of the sites to be examined. Four sites were then sampled (the sand-cliff sites of Baleshare, on the island of the same name off the west coast of North Uist and Hornish Point, South Uist and the deflation sites of South Glendale, South Uist and Newtonferry, North Uist) within a rigorously-defined research framework.The machair sites were formed by sand accretion, facilitated by human activities ranging from construction to refuse disposal and cultivation. Their formation was intermittent and they underwent episodes of major erosion, isolating the sites from the landscape mass of the machair sands. Despite their apparent wealth of suitable material, the dating of Hebridean coastal sites presents special problems. The strategy here was to provide a dating framework for the sequences on each site, from which the dates of archaeological significant structures and events could then be arrived at by extrapolation. Preliminary dates from the earliest and latest strata at Balelone spanned such a small period that a First Millennium BC date-range could be assigned. At Baleshare, the deposits investigated were chiefly later Bronze Age; following abandonment (roughly 200 radiocarbon years) of the Period I cultivated soil Period II represented extensive, manured, cultivated fields in the vicinity of a settlement now lost to the sea. As Period II went on. the settlement seems to have moved closer to the excavated area. After another hiatus of a minimum of 350 radiocarbon years, there were further cultivated plots and associated settlement of Iron Age date (Period III). By contrast, the site at Hornish Point (including successive wheelhouses and associated cultivation areas) is considered to be all of one - dynamic, Iron Age - period, lasting some 300 radiocarbon years (with potentially earlier structures unexcavated). A post-medieval blackhouse of characteristic Lewisian form had been cut into the settlement mound. The three dates from Newtonferry suggest that some Early Medieval activity took place at the site, while the bulk of the deposits date from the thirteenth-fourteenth centuries AD. At South Glendale, the radiocarbon dates indicate occupation sometime between the thirteenth and fifteenth centuries AD; stratigraphically lower, fragmented and truncated remains were prehistoric, probably early Bronze Age.