Plant diversity patterns in subtropical evergreen broad‐leaved forests of Yunnan and Taiwan

Abstract

The subtropical evergreen broad‐leaved forests of Yunnan and Taiwan were compared along environmental and successional gradients with the aim of identifying important taxon and species diversity as well as the drivers of mountain biodiversity patterns. A detrended correspondence analysis of an exhaustive set of data collected from 105 and 223 plots for Yunnan and Taiwan, respectively, was applied to classify natural mature forest types. Additional data from 72 and 68 plots for Yunnan and Taiwan, respectively, were used for analyses of secondary succession. The floristic richness and diversity index were calculated for each type of forest. In Yunnan, the monsoon forests in mesic‐humid sites had more taxa and tended to show higher species diversity than the other two forest types. In Taiwan, species diversity values were significantly higher in the Machilus–Castanopsis zone in the middle altitudes (500–1500 m) than for the other three forest zones. For both Yunnan and Taiwan, the forests at the middle successional stage showed significantly higher species diversity than those at the early successional stage. Differences in diversity between the middle and late stages were not significant. These findings highlight the high species diversity of the natural mature evergreen broad‐leaved forests of both Yunnan and Taiwan. In the secondary forests, as succession proceeds, species diversity comes to resemble that of the natural mature forests. In both ecosystems, the drivers of species diversity patterns are moisture, altitude, and succession/disturbance.

Selection of Native Tree Species for Subtropical Forest Restoration in Southwest China

“…These findings indicate that with careful selection, some later successional species can be incorporated into restoration plantings. However, the other later successional species in our study performed poorly with low survival rates and slow growth, including several species ( Alcimandra cathcartii , Cyclobalanopsis lamellosa , and Lithocarpus hancei ) that are dominant in the nearby natural forest [41, 59]. Further research is needed in order to determine whether the survival and growth rates of these species can be enhanced using methods such as larger seedlings, direct seeding, inoculation with mycorrhizal fungi, increased post-planting care, planting in less degraded sites or planting after the establishment of a pioneer canopy [31, 34, 67].…”

“…The habitats of the selected species were also documented [52]. The studied species were further classified by their forest successional status based on a literature review [41, 52, 59], expert consultations, and the authors’ own field experience (Table 1). …”

“…At present, Chinese natural subtropical evergreen broad-leaved forests exist only in nature reserves or remote, isolated areas. Such forests are dominated by species of Lithocarpus , Castanopsis , and Cyclobalanopsis (Fagaceae), Cinnamomum and Machilus (Lauraceae), Schima (Theaceae), Magnolia , Manglietia , and Michelia (Magnoliaceae) [40, 41]. …”

“…Principles of industrial forestry techniques are emphasized in the training program for the employees of the forest departments and the employees are often unaware how to incorporate native species restoration into their programs [24, 50, 51]. However, some studies have investigated subtropical forest succession [26, 38, 39, 41], making it possible to assign species to successional guilds. Research on the restoration performance of subtropical tree species from different successional guilds and identification of appropriate species for restoration is essential to support large-scale planting.…”

The Subtropical Vegetation of Southwestern China

“…These forests, dominated by the genera Castanopsis , Lithocarpus , Cyclobalanopsis (Fagaceae), Machilus (Lauraceae), Schima (Theaceae), Manglietia and Michelia (Magnoliaceae), and Distylium (Hamamelidaceae) are almost exclusively confi ned to southern, southwestern, and southeastern mainland China, and Taiwan, southwestern Japan, southern Korea, and some mountain regions of Vietnam, Laos, Thailand, Myanmar, India, Bhutan, and Nepal (Kira 1991 ;Ohsawa 1993a ;Tagawa 1995 ;Song 1995Song , 2013Li 1997 ;Tang and Ohsawa 2009 ;Tang et al 2013 ). These forests, dominated by the genera Castanopsis , Lithocarpus , Cyclobalanopsis (Fagaceae), Machilus (Lauraceae), Schima (Theaceae), Manglietia and Michelia (Magnoliaceae), and Distylium (Hamamelidaceae) are almost exclusively confi ned to southern, southwestern, and southeastern mainland China, and Taiwan, southwestern Japan, southern Korea, and some mountain regions of Vietnam, Laos, Thailand, Myanmar, India, Bhutan, and Nepal (Kira 1991 ;Ohsawa 1993a ;Tagawa 1995 ;Song 1995Song , 2013Li 1997 ;Tang and Ohsawa 2009 ;Tang et al 2013 ).…”