Interaction between man and plants.

five studies of present-day weed floras are brought together to address the issue of ancient crop husbandry and how different agricultural practices may be identified from the archaeobotanical record. The studies have provided insights into the complexity of the relationship between the functional attributes of species and their ecological significance in relation to habitat conditions and husbandry regimes. Using a suite of characteristics, practices such as irrigation, fallowing, crop rotation, time of sowing and intensity of cultivation (hoeing, weeding, manuring etc.) can be recognised on the basis of the functional ecology of the weed species accompanying the crops. The geographic variation in functional attributes is limited and permits the identification of husbandry practices in different climatic zones. Recommendations are made for the application of weed ecological methods to archaeobotanical assemblages

carbon isotope discrimination (13C) in charred grains from archaeological sites provides reliable information about water availability of ancient crops. However, as cereals are cultivated plants, they may reflect not only climatic fluctuations, but also the effect on water status of certain agronomic practices, such as sowing in naturally wet soils or irrigation. The authors propose a methodological approach to combine 13C data from different plant species, in order to discriminate between climate-derived and anthropogenic effects on ancient crops. The authors updated previous models for estimating water inputs from 13Cof cereal grains of Hordeum vulgare and Triticum aestivum/durum, and applied them to published data from several archaeological sites, including samples from the Neolithic to the present day in northeast and southeast Spain, as well as from the Neolithic site of Tell Halula (Syria). They found an important decrease in water availability from the Neolithic to the present time in the three areas of study, especially clear for the two driest areas (southeast Spain and northwest Syria). Potential differences in water management practices between wheat and barley, as well as between cereal and legume crops (Vicia faba and Lens culinaris), are also discussed on the basis of the comparison of 13Cvalues across several archaeological sites