Hawaii and the Pacific Islands - U.S. Army Corps of Engineers

ERDC/EL TR-12-5 6ture fluctuations (USDA Natural Resources Conservation Service 2006).However, there is considerable spatial variability in both temperature andrainfall, especially on the higher islands that have greater topographicdiversity and relief.The variety of topographic, soil, and climatic conditions across the region,along with geographic isolation, has encouraged the development of adiverse Pacific flora with many species endemic to particular islands andisland groups. The natural climax communities in the region range fromhigh-elevation alpine and subalpine communities to wet, mesic, and dryhardwood forests, shrublands, grasslands, coastal strand, and coral atollplant communities. Waves of human colonizers added large numbers ofintroduced and invasive plants to the flora, particularly in Hawai‘i. EarlyPolynesian settlers carried with them a number of important food plants,including taro (Colocasia esculenta), sweet potatoes (Ipomoea batatas),breadfruit (Artocarpus altilis), bananas (Musa acuminata), and yams(Dioscorea spp.) (Juvik and Juvik 1998). However, prior to the arrival ofEuropeans, most of the islands remained dominated largely by a complexand unique native flora. Settlement by Europeans (and, later, by Americans,Japanese, and others) led to large-scale agricultural development,primarily for sugarcane (Saccharum officinarum) production in theHawaiian Islands and coconut oil and copra (Cocos nucifera) in AmericanSamoa and the Marianas. Following World War II, lands in sugarcaneproduction were converted to pastureland, secondary agro-forestry, andsubsistence agriculture (Nakamura 1984; Young 1989; USDA NaturalResources Conservation Service 2006). Large-scale agriculture (e.g., forpineapple [Ananas comosus] and coffee [Coffea spp.]) remains prevalentin some areas, along with small commercial enterprises that grow food forlocal consumption. Many areas have become urbanized and industrializedwith large areas utilized for tourism and military purposes.The Hawaiian IslandsIn the Hawaiian Islands, the average daily high temperature is about 84 °F(29 °C) and the average daily low temperature is 67 °F (19 °C) at sea level.However, temperatures at high elevations regularly dip below freezingduring the winter (Juvik and Juvik 1998). Average annual rainfall is about70 in. (1,780 mm), but varies greatly by location in relation to northeasterlytrade winds and topography. Annual rainfall ranges from about10 to 60 in. (254 to 1,524 mm) on leeward slopes, and from 60 to morethan 400 in. (1,524 to more than 10,160 mm) on windward slopes. The