Abstract
Abstract
Background
The ability of overstory tree species to regenerate successfully is important for the preservation of tree species diversity and its associated flora and fauna. This study investigated forest regeneration dynamics in the Cat Ba National Park, a biodiversity hotspot in Vietnam. Data was collected from 90 sample plots (500 m2) and 450 sub-sample plots (25 m2) in regional limestone forests. We evaluated the regeneration status of tree species by developing five ratios relating overstory and regeneration richness and diversity. By examining the effect of environmental factors on these ratios, we aimed to identify the main drivers for maintaining tree species diversity or for potential diversity gaps between the regeneration and the overstory layer. Our results can help to increase the understanding of regeneration patterns in tropical forests of Southeast Asia and to develop successful conservation strategies.
Results
We found 97 tree species in the regeneration layer compared to 136 species in the overstory layer. The average regeneration density was 3764 ± 1601 per ha. Around 70% of the overstory tree species generated offspring. According to the International Union for Conservation of Nature’s Red List, only 36% of threatened tree species were found in the regeneration layer. A principal component analysis provided evidence that the regeneration of tree species was slightly negatively correlated to terrain factors (percentage of rock surface, slope) and soil properties (cation exchange capacity, pH, humus content, soil moisture, soil depth). Contrary to our expectations, traces of human impact and the prevailing light conditions (total site factor, gap fraction, openness, indirect site factor, direct site factor) had no influence on regeneration density and composition, probably due to the small gradient in light availability.
Conclusion
We conclude that the tree species richness in Cat Ba National Park appears to be declining at present. We suggest similar investigations in other biodiversity hotspots to learn whether the observed trend is a global phenomenon. In any case, a conservation strategy for the threatened tree species in the Cat Ba National Park needs to be developed if tree species diversity is to be maintained.
Funder
Vietnamese Government Scholarship
Rufford Foundation
The Open Access Publication Funds of the Georg-August-University Göttingen
Department Silviculture and Forest Ecology of the Temperate Zones of the University of Göttingen
Georg-August-Universität Göttingen
Publisher
Springer Science and Business Media LLC
Reference123 articles.
1. Spracklen BD, Lane JV, Spracklen DV, Williams N, Kunin WE. Regeneration of native broadleaved species on clearfelled conifer plantations in upland Britain. For Ecol Manage. 2013;310:204–12. https://doi.org/10.1016/j.foreco.2013.08.001.
2. Tyagi JV, Kumar R, Srivastava SL, Singh RD. Effect of micro-environmental factors on natural regeneration of Sal (Shorea robusta). J For Res. 2011;22(4):543–50. https://doi.org/10.1007/s11676-011-0197-1.
3. Winter MB, Baier R, Ammer C. Regeneration dynamics and resilience of unmanaged mountain forests in the Northern Limestone Alps following bark beetle-induced spruce dieback. Eur J For Res. 2015;134(6):949–68. https://doi.org/10.1007/s10342-015-0901-3.
4. Ballabha R, Tiwari JK, Tiwari P. Regeneration of tree species in the sub-tropical forest of Alaknanda Valley, Garhwal Himalaya, India. For Sci Pract. 2013;15(2):89–97. https://doi.org/10.1007/s11632-013-0205-y.
5. Diaci J, Kutnar L, Rupel M, Smolej I, Urbancic M, Kraigher H. Interactions of ecological factors and natural regeneration in an altimontane norway spruce (Picea abies (L.) Karst.) Stand. Phyton. 2000;40:17–26.
Cited by
4 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献