Wetland archaeology, a well-established branch within archaeology, occupies itself with areas which are extremely rich in natural resources and provide exceptionally well-preserved material remains; they therefore give excellent possibilities for multidisciplinary (particularly ecological and geo-archaeological) research.1 Such approaches are well-developed in Italian scholarship, especially in the study of pre- and protohistoric periods, as the study of wetlands of the Roman period arguably has a slightly different tradition, taking a more historical approach.2
The volume under review, firmly rooted in this Italian tradition, deals with ´aree umide’ (wetlands) in Italy and how they were managed and transformed into arable land in the Roman period. It combines careful study of relevant historical evidence with an overview of archaeological wetland research in Roman Italy. It presents the published version of the author’s PhD thesis, and is the first volume in a supplementary series of the journal Agri Centuriati, which publishes studies of Roman agricultural landscapes. The volume consists of six chapters, which treat the use and reclamation of wetlands from different angles, both historical and archaeological.3
In chapter 1, Frassine defines the terms he uses to describe different types of wet areas. He distinguishes between natural and anthropogenic wet areas, and then defines different types of wetlands in terms of landscape context (along rivers, on and around lakes, coastal areas), in terms of water depth and permanence of water presence. While this discussion is very systematic, in practice it is extremely difficult to distinguish between different types of wetlands. For example, the difference between a stagno (more than 1m deep) and a palude (between 0.5 and 1m) is in general not immediately obvious, but even more problematic when one is studying conditions in the past.
Such issues also show up clearly when we turn to Roman conceptions of wet places as described in literary sources, which are discussed in chapter 2. Many terms related to such places occur in literary sources (Frassine provides an ample overview), but they do not neatly fit the systematically defined modern concepts. Moreover, different sources use terms such as palus, stagnum, umidus, umectus, and nebulosus in different ways. Only a few juridical texts, dealing with potential conflicts arising from public and/or private use and maintenance of wet areas, particularly along rivers, provide more systematic descriptions of such locations.
At the same time, the literary sources clearly highlight the manifold uses of wetlands. As passage through them was difficult and required expert knowledge, they had a strategic and military importance. They were also used as settlement niches with non-agricultural subsistence strategies, and as areas that could be put to agricultural use. A large variety of crops including turnips, millet, spelt, beets, cabbage, asparagus, melons and courgettes, and also certain types of grapes, were known to grow reasonably well in wet soils. Wetlands provided hunting, fowling and fishing grounds, and were useful for herding, especially of pigs. Wetlands also provided alternative resources, such as medicinal plants, reed and trees that were used as raw materials for roofing, baskets and torches, stuffing for mattresses, fodder, and even compost. Frassine thus rightly and vividly points out that wetlands were an integral and important part of the Roman rural economy.
The next chapters discuss the archaeological evidence for the use and management of wetlands in Italy. Chapter 3 focuses on hydraulic reclamation ( bonifica idraulica). Besides famous projects (canals in France and Greece, parts of Nero’s project to connect the Tiber with the lacus Avernus, dams in the Tiber to improve navigability), measures to regulate and control water levels in rivers, lakes and other wet areas are reviewed. These range from the underground canals constructed to drain the Alban lakes and the Lacus Fucinus, the large-scale drainage of tufa areas through systems of cuniculi in central Italy, and the construction of canals in the Po plain, to the closing of areas as water basins, the opening up of coastal lakes to the sea in order to create fish breeding grounds, and small-scale land improvements such as artificial filling of depressions, the construction of sewers, the improvement of drainage and/or lowering of the water table through deposits of amphorae, and the use of wooden foundations for construction in wet unstable soils. While of varying scale, many of these projects were multi-purpose; for example, the canals on the Fucine lake not only controlled the water level but also drained surrounding areas, provided water for irrigation and improved water flow in nearby rivers, thereby increasing their navigability. Such projects clearly highlight Roman environmental knowledge and engineering skills.
Chapter 4 discusses works that are subsidiary to hydraulic reclamation and/or used to prevent potential drainage problems. These works include the reinforcement of river banks ( munitio riparum) and the construction of embankments ( aggeres), dikes and dams, which were often an integral part of agricultural reclamations, for example as part of centuriation systems.
Chapter 5 turns attention to agricultural land reclamation ( bonifica agraria) in Roman Italy. Preparing land for arable farming obviously entailed the control and removal of water, and there is therefore overlap with the previous chapters in terms of the evidence discussed. The chapter starts out with a review of evidence in the written sources regarding the drainage of land through the construction of ditches (both open-air and covered). A point that stands out here is the importance of and effort put into maintenance, and the potential juridical issues if a landowner did not maintain his drainage works and consequently caused damage. Finally, written sources show that ditches were also important to divide the land (and keep away animals), while sediment and plants accumulating in them provided nutrient-rich organic matter to fertilize and elevate the land.
Next, Frassine discusses the sparse archaeological evidence pertaining to ditches and other drainage works; he mentions occasional ditch sections investigated in Latium, some more elaborate systems of ditches in Campania and investigations of centuriation systems in northern Italy. The types of ditches and drains observed in these archaeological data have similar characteristics to those mentioned in written sources; they are differentiated by geological context, but their chronological relationship is unknown. Frassine also presents an interesting model from nineteenth-century sources of how a modest (10 ha) plot would have been drained by a hierarchical system of ditches. One would like to evaluate this model on the basis of archaeological data, but the scarce and fragmentary evidence that is presented unfortunately does not allow this.
The third section of chapter 5 turns to the role of centuriation systems as hydrological/ reclamation works — an aspect of these systems that the author rightly points out is often neglected in favour of the study of the measures used in their laying-out and their chronology. Frassine focuses on centuriation systems in northern Italy, discussing several examples in some detail to illustrate how such large-scale projects adapted to the local landscape and hydrology. He argues that centuriation systems would generally systematically parcel out higher areas, while lower areas were settled in a more adaptive way, with settlement occurring only where local topography allowed it on small elevations. While this model may hold true for some areas, it is unclear if it is applicable to all centuriated areas.4
The discussion of centuriation systems also shows that there is a lot of scope for future research into these systems through fieldwork and environmental research: the only area Frassine mentions where extensive excavation of ditches has occurred in combination with sedimentological and morphological analyses are the Valli Grandi Veronesi in the lower Po plain. Such research clearly aids in understanding the working of the drainage system and its relation to rural settlement.
The final chapter (6) presents a short summary of the main points arising from the previous chapters. First, while modern perceptions and the ancient sources generally provide a negative view of wetlands, they were surely exploited and an important part of daily life; second, the Romans show good hydraulic engineering skills as well as a detailed knowledge and understanding of landscape and soil characteristics in the various reclamation and drainage projects discussed; and third, their vocabulary does not point to the existence of a systematic theoretical classification or definition of wetland environments. Important as these observations are, a more structured and extensive discussion of these issues would have further underlined the importance of the subject for our understanding of Roman engineering and the possible links with wider economic and demographic developments.
In sum, the volume forms a very important contribution to the study of wetlands in Roman Italy and the ways in which the Romans managed and exploited them. It combines a detailed review of literary sources with an excellent overview of archaeological work on the subject, opening up important (mainly Italian-language) bibliography as well. A minor note concerns the images, which are sometimes difficult to relate to the text because reference numbers or toponyms are lacking or difficult to read.
Frassine’s work also shows that archaeological data are still scarce, fragmentary and extremely difficult to date. As a consequence, our understanding of the chronological and spatial dimensions of wetland reclamation and management is still limited (did reclamation techniques evolve? Did their scale change? Were there major phases of reclamation and /or regional trends?) — although of course written sources do provide valuable information on such issues. Also, the kind of wetland archaeology common in other areas and time-periods could arguably contribute a lot to our understanding of Roman wetlands. Targeted fieldwork (excavation of centuriation ditches, canals) combined with environmental sampling, geoarchaeological and palaeobotanical research would enrich our understanding of the environmental impact of reclamation projects, and at the same time also help to illuminate the engagement of those living and working in the wetlands of Roman Italy.
Notes
1. F. Menotti and A. O’Sullivan, The Oxford Handbook of Wetland Archaeology (Oxford, 2012).
2. Giusto Traina’s work on the perception of marginal landscapes in the historical sources has been ground-breaking in this tradition (G. Traina, Paludi e bonifiche del mondo antico, Rome 1988). Many Italian archaeologists combine a detailed analysis of archaeological evidence with the evidence from written sources as well; for some important contributions, see papers in L. Quilici and S. Quilici Gigli, Interventi di Bonifica Agraria nell’Italia Romana (Rome, 1995).
3. The author uses several variants of the term bonifica, which in general indicates amelioration or improvement of terrain and includes not only works that regulate and/or remove water from an area, but also subsidiary and preventive works (p. 14). Bonifica idraulica entails all works to discard water and/or to reduce the humidity of an area (p. 155). Bonifica agraria includes all such works which are done to improve conditions for arable farming. The term bonifica integrale incorporates different aspects, including hydrological works, disease control and agricultural improvements in a broad sense (that is, including the construction of roads, farms, etc.; see p. 149).
4. For example, in the Pontine region a centuriation system was laid out in the lowest-lying part of this coastal plain. Settlements occur in this area, although they are not distributed evenly. A more systematic review of centuriation systems in other parts of Italy, although arguably less well-studied and therefore not rendering the same type of data, would have been useful to clarify and/or better understand potential variations in the workings and adaptations of these reclamation works.