Spatial Patterns of Tree Species Number in Relationship With the Local Environmental Variations in Karst Ecosystem

Abstract

Karsts are recognized as fragile environments where, forest degradation is faster and the composition and growth rate of vegetation is considered as a product of the interactions between karst ecological factors. A representative sample of vegetation plots from a systematic sampling was analyzed in Longhushan, southwest China. The sampling combined measurements of species number with extensive information on geological, environmental, and soil factors to establish species response to the single or combined influence of these factors. Both General and Generalized Linear Models predicted richness as a function of the combination of variables from the three groups. Richness increased with elevation, slope, moisture, and in dolomite dominated areas, but decreased with organic matter. Patterns of richness were dependent on complex relationships between soil, geological, and environmental factors, within this complexity it appeared that rock type played an important role. Evidence of significant variations was provided after combining variables from the three groups, suggesting their interactions influence on plants. Our findings have implications for the understanding of these interactions and suggest that plant species can be affected by it, and also carbonate rock type may be an important parameter to consider while examining relationships between plant and environmental factors in karst areas.

Karst tiankengs as refugia for indigenous tree flora amidst a degraded landscape in southwestern China

“…Restoring the vegetation in the degraded karst areas is a major challenge for biodiversity conservation and regional development 30 , 31 , since these areas have undergone longtime environmental degradation and biodiversity loss due to geological and climatic processes, as well as intense human activities 32 , 33 . However, the recent discoveries of tiankengs (large dolines) in the karst area of southwestern China have shed light on this goal, because tiankeng habitats may have preserved the intact vegetation from a long–ago period.…”

Bryophyte diversity in karst sinkholes affected by different degrees of human disturbance

“…Our results show that the bryophyte distribution is influenced by not only microhabitat factors such as temperature and humidity but also topographic factors. Toure et al [41] believed that the effects of geomorphology on inversion intensity, diurnal temperature field, and vertical temperature gradient have a great influence on vegetation pattern and plant survival. Altitude gradient is one of the most common determinants for shaping the spatial pattern of species richness [42].…”

“…Intensive human interference not only destroys its unique esthetic value but also leads to the degradation of its environmental value [12]. Plant communities and biodiversity are considered to be highly spatial variabilities controlled by both abiotic and biotic factors [41]. Many types of environmental changes may affect processes that can increase or decrease diversity [54].…”