Search

Although carbon storage in ecosystems and biological diversity have been central issues of environmental and ecological sciences for a decade, a reciprocal relationship between diversity and productivity of ecosystems is still unknown. To reveal such the reciprocal relationship, we measured the microtopography around some tree groups, estimated fl ows and stocks of organic matters in soils in the form of litters and roots under three kinds of microtopographic conditions, measured decomposition rates, and detected the shift of distribution patterns of dominant species among growing stages in relation to locations of tree groups creating specifi c microtopographic conditions in a tropical peat swamp forest. The results suggest that heterogeneity of peat accumulation rate results in undulating peat surface. Such undulating peat surface contributes to habitat differentiation of tree species, because subtle difference in peat surface elevation determines the degree of fl ooding, which affects survival rates of plants differently according to species. Such the distribution of plant species formed through the above process determines local regime of organic matter dynamics that determines peat surface conditions of near futures. Thus, in tropical peat swamp forests diversity and productivity were closely interdependent to each other, although the diversity has attracted less attention than carbon storage function.

Hani people in the Ailao Mountains, Yunnan, Southwest China, cultivate rice in terraced fi elds on step slopes below the cloud line (1800 m alt.). Traditionally, the cloud-zone slopes were used in various ways, including alder forests as fuel and wood sources and primary mossy forests as sacred areas (god-mountains) and watershed areas. In the Dayuejin (great advance) period (1960s), trees of cloud zone were consumed as fuel for iron production. The alder forests and god-mountains disappeared, but canopy trees of the watershed forests were protected by villagers. In the 1980s, the government distributed sloped areas to villagers for them to re-forest and manage. Such lands are called ziliushan (self-managed forests). In ziliushan, Hani people preferred to plant familiar tree species that were components of the former alder forests, instead of the shanmu (Cunninghamia lanceolata) nursery trees distributed by the government. At the same time, villagers replanted the god-mountains and reinforced the protection of watershed forests. Here, I discuss the villagers' incentives for vegetation management and the roles of newly replanted god-mountains.

この論文は国立情報学研究所の学術雑誌公開支援事業により電子化されました。

この論文は国立情報学研究所の学術雑誌公開支援事業により電子化されました。

この論文は国立情報学研究所の学術雑誌公開支援事業により電子化されました。

A new species is described in Tetrapetalum, a small genus of which two species have been known. Although Van Heusden (1992) stated that Tetrapetalum differs from Cyathostemma only in its dimerous flowers, Tetrapetalum seems to be more closely related with Uvaria than with Cyathostemma, because of spreading petals and unlobed stigmas. A key to the three species of Tetrapetalum is provided here.

Hani people in the Ailao Mountains, Yunnan, Southwest China, cultivate rice in terraced fi elds on step slopes below the cloud line (1800 m alt.). Traditionally, the cloud-zone slopes were used in various ways, including alder forests as fuel and wood sources and primary mossy forests as sacred areas (god-mountains) and watershed areas. In the Dayuejin (great advance) period (1960s), trees of cloud zone were consumed as fuel for iron production. The alder forests and god-mountains disappeared, but canopy trees of the watershed forests were protected by villagers. In the 1980s, the government distributed sloped areas to villagers for them to re-forest and manage. Such lands are called ziliushan (self-managed forests). In ziliushan, Hani people preferred to plant familiar tree species that were components of the former alder forests, instead of the shanmu (Cunninghamia lanceolata) nursery trees distributed by the government. At the same time, villagers replanted the god-mountains and reinforced the protection of watershed forests. Here, I discuss the villagers' incentives for vegetation management and the roles of newly replanted god-mountains.