Agriculture in Hawaiʻi was developed in response to the high spatial heterogeneity of climate and landscape of the archipelago, resulting in a broad range of agricultural strategies. Over time, highly intensive irrigated and rainfed systems emerged, supplemented by extensive use of more marginal lands that supported considerable populations. Due to the late colonization of the islands, the pathways of development are fairly well reconstructed in Hawaiʻi. The earliest agricultural developments took advantage of highly fertile areas with abundant freshwater, utilizing relatively simple techniques such as gardening and shifting cultivation. Over time, investments into land-based infrastructure led to the emergence of irrigated pondfield agriculture found elsewhere in Polynesia. This agricultural form was confined by climatic and geomorphological parameters, and typically occurred in wetter, older landscapes that had developed deep river valleys and alluvial plains. Once initiated, these wetland systems saw regular, continuous development and redevelopment. As populations expanded into areas unable to support irrigated agriculture, highly diverse rainfed agricultural systems emerged that were adapted to local environmental and climatic variables. Development of simple infrastructure over vast areas created intensive rainfed agricultural systems that were unique in Polynesia. Intensification of rainfed agriculture was confined to areas of naturally occurring soil fertility that typically occurred in drier and younger landscapes in the southern end of the archipelago. Both irrigated and rainfed agricultural areas applied supplementary agricultural strategies in surrounding areas such as agroforestry, home gardens, and built soils. Differences in yield, labor, surplus, and resilience of agricultural forms helped shape differentiated political economies, hierarchies, and motivations that played a key role in the development of sociopolitical complexity in the islands.
Noa Kekuewa Lincoln and Peter Vitousek
The Sahel or Sahil is in a sense the “coast” of the Sahara and its cities major “ports” in trade circuits linking long-standing regional exchange in the products of different ecozones to the markets of the Mediterranean through the trans-Saharan trade. Despite botanical diversity and the capacity to support high concentrations of humans and livestock, the productivity of this region depends upon a single unpredictable annual rainy season. Long- and short-term fluctuations in aridity have required populations specializing in hunting, farming, fishing, pastoralism, gold mining, and trade to be mobile and to depend upon one another for their survival. While that interdependence has often been peaceful and increasingly facilitated through the shared idiom of Islam, it has also taken more coercive forms, particularly with the introduction of horses, guns, and a dynamic market in slaves. Although as an ecozone the region stretches all the way to the Red Sea, the political Sahel today comprises Senegal, Mauritania, Mali, Burkina Faso, Niger, and Chad—all former French colonies. France’s empire was superimposed upon the existing dynamics in the agropastoral meeting ground of the desert edge. Colonial requirements and transportation routes weakened the links between the ecozones so crucial to the success of states and markets in the region. Despite the abolition of slavery in 1905, France tacitly condoned the persistence of servile relations to secure requisitions of labor, food, and livestock. Abolition set off a very gradual shift from slavery to other kinds of labor patterns which nonetheless drew upon preexisting social hierarchies based upon religion, caste, race, and ethnicity. At the same time, gender and age gained in significance in struggles to secure labor and status. “Black Islam” (Islam noir), both invented and cultivated under French rule, was further reinforced by the bureaucratic logic of the French empire segregating “white” North Africa and “black” sub-Saharan Africa from one another. Periodic drought and famine in the region has prompted a perception of the Sahel as a vulnerable ecological zone undergoing desertification and requiring intervention from outside experts. Developmentalist discourse from the late colonial period on has facilitated the devolution of responsibilities and prerogatives that typically belong to the state to nongovernmental bodies. At the same time, competition over political authority in the fragmented postcolonial states of the Sahel has often reinscribed and amplified status and ethnic differences, pitting Saharan populations against the governments of desert edge states. External and internal radical Islamic movements entangled with black market opportunists muddy the clarity of the ideological and political stakes in ways that even currently (2018) further destabilize the region.