Biodiversity and recovery of faunal communities after fire disturbance in Hong Kong.

• Other Authors: Cheung, Kwok Leung
• Format: Others
• Language: English; Chinese; Chinese
• Published: 2012
• Subjects: Animal diversity; Wildfires; Wildfires > China > Hong Kong; Restoration ecology; Restoration ecology > China > Hong Kong; Ecological disturbances; Ecological disturbances > China > Hong Kong
• Online Access: http://library.cuhk.edu.hk/record=b5549422; http://repository.lib.cuhk.edu.hk/en/item/cuhk-328035

香港的山火主要是由於氣候及人類活動所引發，嚴重威脅著一些陸地上生物多樣性豐富的生境（如灌木林和林地）。在華南地區，有關火燒地的動物群落恢復生態學硏究的資料非常少，所以本硏究旨在調查山火後動物群落的復原，以及比較天然復原的林區及人工植林的生境恢復之差異。此外，枯枝落葉、物理因素及山火後的微生物對動物群落的影響亦會在此硏究中詳细分析。 === 在亞熱帶地區，地棲無脊椎動物群落的復原速度相對為慢，例如螞蟻群落需要12年的時間才能復原，但人工種植於火燒地能成功地加快其復原速度。 === 無脊椎動物群落與植被結構、山火之後的時間及生境發展都有一定的關係。山火發生兩年後火燒地的鳥類和無脊椎動物的數量、種或科的豐富度、單一性、多樣性及所有無脊椎動物的生物量都比參考樣地低，這意味著山火對動物群落有著長遠的影響。Pheidole spp. 及Tapinoma sp. 1 屬的螞蟻、隠翅甲科及小蠹科的甲蟲、管巢蛛科及狼蛛科的蜘蛛，牠們的數量，以及數量與生物量之比 (ABC plot) 都能用作反映火燒地的生態復原及演替進度的指標。 === 人工種植能夠使生態系統得到長遠的持續建立，對於動物群落的恢復非常重要。是次研究結果顯示人工種植能促進本地無脊椎動物的建群，其數量和群落亦會隨時間增加而增加。這很可能是由於山火後人工種植能為無脊椎動物創造較好的生存條件。其中，相對於原生樹種，外來樹種更有利於無脊椎動物的建群。在外來品種的人工種植區，微生物的數量較低，枯枝落葉的被分解速度較慢，加上生長速度快的外來品種能製造大量的枯枝落葉，這些都顯著增加了枯葉層的深度。較深的枯葉層為無脊椎動物提供了適宜的微生境，有利於其建群。 === 總的來說，在火燒地進行人工植樹能加快動物在火燒地的復原速度，這種方法是有效且成功的。人工種植時採用適當的品種能夠促進及預測早期的植被演替。根據此次硏究結果，我們建議在火燒地上種植生長快速的外來樹種，以加快無脊椎動物的建群。植被蓋度對動物的建群很重要，但植物和結構的多樣性及枯枝落葉層對無脊椎動物的建群更為重要。 === Hill fire in Hong Kong is mainly caused by a combination of weather and human activities. Fire is a major threat to terrestrial animal communities especially in shrublands and woodlands which have a rich faunal diversity. Since research done on hill fire ecology in southern China, especially on faunal colonization after fire, is very scarce, this research attempted to investigate the recovery of fauna after fire disturbance, and the difference in recovery between natural regeneration and artificial planting. Besides, the effects of litter and physical parameters on fauna community as well as the effect of fire on soil microbial community structure were studied. === The recolonization of ground-dwelling invertebrates was relatively slow in the study area, while proactive planting has been successful because they have considerably accelerated the return of fauna at the fire-affected sites. Ground-dwelling invertebrate communities appeared to be less resilient to fire in subtropical environment; the ant composition in the experimental plots needed 12 years to recover. === The composition of the ground-dwelling communities differed among study sites and was correlated with vegetation structure and time since last fire. They showed the trends in the development of invertebrate community composition in association with habitat development. Abundance, species/family richness, evenness, diversity of birds and ground-dwelling invertebrates, and biomass of total invertebrates were lower on the burned site than the reference site even 2 years after fire, implying that fire had longer-term impacts on the faunal communities. Ants such as Pheidole spp., Tapinoma sp. 1, beetles such as Staphylinidae, Scolytidae, and spiders such as Clubionidae, Lycosidae, as well as the abundance biomass comparison (ABC plot) can be chosen to reflect the situation or the recovery process and succession of the fire-affected sites. === The establishment of fauna in proactive planting is vital if ecosystem functions are to be reestablished and restorations to be sustained in the long term. In general the invertebrate data suggest that restoration plantings facilitated the reestablishment of indigenous invertebrate species and invertebrate community changed with time. Proactive plantings created better conditions for ground-dwelling invertebrates after fire, and exotic species with faster growth rate seem to be better than the natives. In exotic plantations, lower decomposition rate of litter provided by the lower microbial population together with higher productivity of exotic species of plants caused a higher litter depth, which provided more microhabitats for ground-dwelling and litter-dwelling invertebrates than the native plantations. === Correct species selection in proactive planting is essential to facilitate and determine the early stages of plant succession. The present study suggests that initial floristic composition is significant in proactive plantings and exotic species with fast growth rate is an effective planting species for invertebrate recolonization. Although plant cover is of importance to developing fauna, the provision of adequate floristic and structural diversity and the presence of logs and litter are important for the full range of native invertebrate recolonization. === Detailed summary in vernacular field only. === Detailed summary in vernacular field only. === Detailed summary in vernacular field only. === Detailed summary in vernacular field only. === Detailed summary in vernacular field only. === Cheung, Kwok Leung. === Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. === Includes bibliographical references (leaves 192-219). === Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. === Abstract also in Chinese; some appendixes also in Chinese. === Abstract --- p.i === Acknowledgements --- p.vi === Table of contents --- p.vii === List of figures --- p.x === List of plates --- p.xvi === List of appendices --- p.xvii === Chapter Chapter 1 --- General Introduction --- p.1 === Chapter 1.1 --- Ecology of Fire --- p.1 === Chapter 1.2 --- Effects of Hill Fire on Soil --- p.3 === Chapter 1.3 --- Effects of Hill Fire on Microbial Communities --- p.7 === Chapter 1.4 --- Effects of Hill Fire on Vegetation --- p.10 === Chapter 1.5 --- Effects of Hill Fire on Fauna Communities --- p.14 === Chapter 1.6 --- The Use of Bioindicators on Restoration Ecology --- p.19 === Chapter 1.7 --- Hill Fire Situation and Research in Hong Kong --- p.23 === Chapter 1.8 --- Study Objectives --- p.28 === Chapter Chapter 2 --- Faunal Colonization after Fire Disturbance --- p.30 === Chapter 2.1 --- Introduction --- p.30 === Chapter 2.2 --- Materials and Methods --- p.32 === Chapter 2.2.1 --- Study sites --- p.32 === Chapter 2.2.2 --- Measurements of soil physicochemical parameters --- p.35 === Chapter 2.2.3 --- Determination of vegetation parameters --- p.36 === Chapter 2.2.4 --- Monitoring of vertebrate communities --- p.36 === Chapter 2.2.5 --- Sampling, sorting and identification of invertebrates --- p.37 === Chapter 2.2.6 --- Data analysis --- p.38 === Chapter 2.3 --- Results --- p.41 === Chapter 2.3.1 --- Soil physicochemical characteristics --- p.41 === Chapter 2.3.2 --- Vegetation parameters --- p.42 === Chapter 2.3.3 --- Vertebrate communities --- p.44 === Chapter 2.3.4 --- Invertebrate communities --- p.47 === Chapter 2.4 --- Discussion --- p.58 === Chapter 2.5 --- Conclusions --- p.66 === Chapter Chapter 3 --- Effect of Different Planting Approaches on Invertebrates --- p.68 === Chapter 3.1 --- Introduction --- p.68 === Chapter 3.2 --- Materials and Methods --- p.70 === Chapter 3.2.1 --- Study sites --- p.70 === Chapter 3.2.2 --- Proactive planting --- p.71 === Chapter 3.2.3 --- Measurement of soil, vegetation, and faunal parameters, and data analysis --- p.73 === Chapter 3.3 --- Results --- p.75 === Chapter 3.3.1 --- Soil physicochemical parameters --- p.75 === Chapter 3.3.2 --- Vegetation parameters --- p.77 === Chapter 3.3.3 --- Invertebrate communities --- p.78 === Chapter 3.4 --- Discussion --- p.92 === Chapter 3.5 --- Conclusions --- p.98 === Chapter Chapter 4 --- Long-term Changes of Invertebrate Community after Hill Fire by a Retrospective Approach --- p.100 === Chapter 4.1 --- Introduction --- p.100 === Chapter 4.2 --- Materials and Methods --- p.102 === Chapter 4.2.1 --- Study sites --- p.102 === Chapter 4.2.2 --- Measurement of soil physicochemical parameters --- p.102 === Chapter 4.2.3 --- Determination of vegetation parameters --- p.103 === Chapter 4.2.4 --- Collection, sorting and identification of invertebrates --- p.104 === Chapter 4.2.5 --- Data analysis --- p.104 === Chapter 4.3 --- Results --- p.105 === Chapter 4.3.1 --- Soil physicochemical characteristics --- p.105 === Chapter 4.3.2 --- Vegetation parameters --- p.106 === Chapter 4.3.3 --- Invertebrate communities --- p.110 === Chapter 4.4 --- Discussion --- p.123 === Chapter 4.5 --- Conclusions --- p.133 === Chapter Chapter 5 --- Relationship of Microbial Community with Recolonization of Invertebrates --- p.135 === Chapter 5.1 --- Introduction --- p.135 === Chapter 5.2 --- Materials and Methods --- p.139 === Chapter 5.2.1 --- Study sites --- p.139 === Chapter 5.2.2 --- Microbial biomass carbon (C[subscript mic]) and nitrogen (N[subscript mic]) --- p.139 === Chapter 5.2.3 --- Fatty acid methyl esters (FAME) extraction --- p.140 === Chapter 5.2.4 --- Data analysis --- p.141 === Chapter 5.3 --- Results --- p.142 === Chapter 5.3.1 --- Fumigation-extraction --- p.142 === Chapter 5.3.2 --- Fatty acid methyl esters --- p.144 === Chapter 5.3.3 --- Relationship of microbial communities with physicochemical, vegetation and invertebrate parameters --- p.145 === Chapter 5.4 --- Discussion --- p.152 === Chapter 5.5 --- Conclusions --- p.159 === Chapter Chapter 6 --- Effects of Critical Factors on Invertebrate Communities --- p.160 === Chapter 6.1 --- Introduction --- p.160 === Chapter 6.2 --- Materials and Methods --- p.162 === Chapter 6.2.1 --- Experimental sites --- p.162 === Chapter 6.2.2 --- Critical factors selection and simulation --- p.163 === Chapter 6.2.3 --- Measurement of microclimatic characteristics --- p.165 === Chapter 6.2.4 --- Collection, sorting and identification of invertebrates --- p.166 === Chapter 6.2.5 --- Data analysis --- p.166 === Chapter 6.3 --- Results --- p.167 === Chapter 6.3.1 --- Microclimatic characteristics --- p.167 === Chapter 6.3.2 --- Invertebrate communities --- p.168 === Chapter 6.4 --- Discussion --- p.173 === Chapter 6.5 --- Conclusions --- p.178 === Chapter Chapter 7 --- General Conclusions --- p.180 === Chapter 7.1 --- Overall Discussion --- p.180 === Chapter 7.2 --- Limitation of the Present Study and Future Research --- p.184 === Chapter 7.3 --- Contributions to Our Knowledge --- p.188 === Reference --- p.192 === Appendices --- p.220