p. 32 “… particulars had to be learned by human users, sometimes through processes of trial and error. Early Neolithic clearances of fields in upland Britain became moorland and peat bog under later wetter conditions. Bronze Age clearances for pasture in Denmark strained local wood supplies to the point that some pasture was left to grow back as trees.”
p. 34 Mediterranean Europe acquired its Neolithic agriculture complex from southwestern Asia during the sixth and fifth millennium BCE. At first this comprised cereal grasses, legumes, and ovicaprida… intensive hand labour by humans maintained the system until draught animals (oxen, donkey) and a simple plough arrived by the early Bronze Age…. Crops had to be adapted to the rainy cool winter and the hot dry summer: annual cereals seeded in autumn grow throughout the winter and spring to mature before the summer drought; perennial grasses, vines, olives and other plants go dormant or otherwise adapt to the heat. .. Grain, olives and vines have formed the ruling trinity of Med crops since pre-classical times, providing the ancient staple diet of bread, oil and wine. Less stereotyped legumes from field or garden could provide important supplements. Grain crops, wheat and barley, … were reared on ploughed fields (ager) on a two-year cycle, alternating crop and fallow. Resting the field one year in two and ploughing the weeds under hoarded two years of previous water for the grain. Bare fallow leaves the soil surface open during the winter rains, both absorbing water and risking erosion. … Olive trees, … sensitive to frost … on the north they tidily mark a natural boundary of Mediterranean agriculture, which mostly coincided with that of the Roman world. .. Wines and olives might be grown beside vegetables in gardens, but especially when raised for family subsistence were often interplanted in grain fields as cultura mixta. … Livestock played a secondary role … a major technical problem inhibited livestock rearing in the Med, as summer forage was sparse in agricultural areas long cleared of most woodlands and subject to summer drought. The typical response even before good written records was vertical transhumance; a semi-annual movement of livestock and their keepers … to summer pastures in the mountains. The practice moved the animals to forage at the price of depriving the arable land of their manure and the risk of overgrazing upland woodlands and turning them to grass, maquis or garrigue. Transhumance componmuded the problem of fertility maintenance in Med dry farming, an issue that much worried Roman agricultural writers.”
p. 52-54 During and after Roman fall “a long series of epidemics and losses of regional populations caused inhabitants of the western provinces to decline steadily in numbers from the 15-20 million range of the second century to 8-10 million about 600. The economy lost its urban focus… environmental forces of both natural and anthropogenic origins had some significance in this evolution, while even more can be attributed to the environmental impacts of the cultural changes themselves. … [the end of ] the relatively warm and dry Roman Optimum… by the third century, falling general sea levels reveal, and traces of volcanic activity in ice cores help explain, a general cooling that continued into the fourth century, although some regions then became drier. In the Alps, the glaciers were advancing and the tree line creeping downwards. In winter 406, the lower Rhine surprisingly froze solid, giving Germanic invaders easy passage to plunder in Gaul. The ensuing fifth century, in Europe at least, was cooler still, and in the north up to c.450 wetter, but aridity in the southern Med is blamed for abandoned North African farmland. If, as some writers now estimate, mean annual temperatures declined by 1-1.5C from the second century to the sixth, Europe outside the Med basin was becoming less amenable to the favoured crops of Med agrosystems….
Severe pandemics ravaged the Empire during the late second century and again in the mid-third, killing as much as a third of its inhabitants. Some may rather have succumbed to ensuing food shortages and famines… most modern authorities now think these were smallpox, measles or influenza rather than plague. .. most famous is the ‘Justinian plague’, named retrospectively for East Roman Emperor Justinian (527-65)… Most late 20th-century scholars accepted this as the first pandemic of bubonic plaque … less tendentious label for the entire episode is Late Medieval Pandemic. Whatever the pathogenic agent, it was new or long unfamiliar in the region, entered from Africa, probably by way of Egypt, and caused many deaths. … a possibly new endemic presence of malaria… whose several varieties had colonized the Med since at least the sixth and fifth centuries BCE. … the form most common in the western Med debilitated rather than immediately killed, leaving victims with weakened immune systems and life spans shortened by other diseases, and persuading survivors to abandon marshy areas. …