Some Extensions of Mills's Method for Urban Population Density Gradient Estimation

This paper extends Milk's method for estimating urban population density gradients to general noncircular and asymmetrical urban forms, using Gauss-Legendre quadrature embedded in a Newton-Raphson root finding algorithm. We also examine the sensitivity of the Mills method to measurement errors in the assumptions. Several issues arising from the comparison of analytical, Mills type estimation procedures with statistical procedures are explored, particularly in light of recent work that questions the negative exponential formulation of urban density gradients. We note in particular the influence of secondary population centers as a source of estimation bias.     

Irrigated taro (Colocasia esculenta) farming in North Kohala,Hawai‘i: sedimentology and soil nutrient analyses

How did traditional farming transform the natural environment in the Hawaiian Islands? This question is one that has largely been addressed for rainfed farming of crops like sweet potato (Ipomoea batatas), but evidence is lacking for irrigated farming of the critical staple crop taro (Colocasia esculenta). We describe the results of soil nutrient and sedimentological analyses of deeply-stratified pondfield deposits representing a 600-year-long record of irrigated taro farming in the North Kohala District, Hawai‘i Island. Soil is categorized by particle size to determine modes of transport and deposition, and concurrent soil nutrient analyses were conducted to infer shifts in the source of sediments and changes associated with taro harvesting. The advent of farming is clearly detectable in sedimentology, the presence of charcoal found within sediments, and soil chemistry. However, diminished nutrient concentrations can be attributed largely to deposition of a mixture of upstream sediments. Overall, there is no clear evidence for nutrient draw-down by taro harvesting, but we cannot yet rule it out as a factor. This study demonstrates the inherent difficulty of correlating changes in soil nutrients evident in irrigated pondfields with the long term history of soil nutrient cycling.     

Ancient Maritime Fish-Traps of Brittany (France): A Reappraisal of the Relationship Between Human and Coastal Environment During the Holocene

The present-day maritime landscape of Western France forms the geographical framework for a recent research project dedicated to the archaeological study of ancient fish-traps, combining regional-scale and site-scale investigations. Based on the compilation and exploitation of a large unpublished dataset including more than 550 sites, a preliminary synthetic study allows us to present some examples of synchronic and thematic approaches, and propose a morphological classification of the weirs. These encouraging first results open up new perspectives on fish-trap chronology closely linked to wider studies on Holocene sea-level changes.     

The impact of broadband and other infrastructure on the location of new business establishments

This paper analyzes the impact of broadband infrastructure, along with a range of other local characteristics such as motorways and other infrastructure, availability of human capital, and access to third‐level educational facilities, on the location of new business establishments. The sample period spans the introduction and recent history of broadband in Ireland. The results indicate that the availability of broadband infrastructure is a significant determinant, but its effects may be mediated by the presence of sufficiently high human capital in an area.     

The Difficult Place of Deserted Coasts in Archaeology: New Archaeological Research on Cooks Beach (Pukaki), Coromandel Peninsula,New Zealand

Sites which have been occupied semi-continuously in the past present some inherent difficulties for archaeology. Here we present new research from a coastal site on the North Island of New Zealand at Cooks Beach where anthropogenic vegetation changes are seen using microfossil analysis of obsidian tools, sediments and pit fill. The results indicate the initial presence of people in AD 1300–1400 followed by subsequent periods of disuse or abandonment and sweet potato (Ipomoea batatas) cultivation. Around the time of initial settlement, obsidian from this location is found at sites across the country. After AD 1400 the area appears to be deserted for a century or more, after which we see evidence for the cultivation of sweet potato in AD 1500 as evidenced by extensive soil modification and numerous storage pits. There is no evidence of a permanent settlement at the site. The geographic distribution of Cooks Beach obsidian was constricted while the site was used for sweet potato cultivation, a pattern often attributed to increased warfare. It appears cultivation was abandoned after AD 1650 marking a second secession of use, a fact confirmed in AD 1769 when Captain Cook visited the area. We consider the possible drivers for the late abandonment of cultivation at Cooks Beach.     

Airborne lidar survey of irrigated agricultural landscapes: an application of the slope contrast method

Irrigated agriculture was central to the economies of many of the world’s best known complex societies. New high-resolution digital elevation models (DEM) derived from remotely sensed lidar data give archaeologists the opportunity to study field systems at a scale not previously possible. Here we describe a method called slope contrast mapping that takes advantage of the dissimilarity between artificial and natural slopes to identify and map discrete features. We use this relatively simple method in our own research to identify complexes of agricultural terraces in the North Kohala district, Hawai’i Island. It has also proved useful for mapping the natural landscape, specifically the extent of flat land between valleys suited for irrigated agriculture.     

A cost surface model of volcanic glass quarrying and exchange in Hawai‘i

The spatial distribution of artifacts from the Pu‘u Wa‘awa‘a volcanic glass source (North Kona District, Hawai‘i Island) shows a pattern of direct access by those living in the immediately vicinity of the source with subsequent down-the-line exchange. Most quarrying and exchanges likely occurred within a single day’s travel from sites where artifacts were deposited. The exception to this is the discovery of non-local direct access evident in assemblages from the extreme southern end of Hawai‘i Island; these visits may have involved voyages by canoe. While people did not often travel far for volcanic glass they nonetheless appear to have had unfettered accessed to source material and freely conducted inter-community exchanges. This implies volcanic glass was treated as a common pooled resource and the existence of informal exchange relationships.