Probing on the relationship between rock desertification development status and spatial patterns for the dominant landscapes types in the typical karst area

2012 ◽  
Author(s):  
Zhongfa Zhou ◽  
Bo Li ◽  
Xiaoying Yang
Keyword(s):  
Spatial Patterns ◽  
Karst Area ◽  
Development Status ◽  
Rock Desertification ◽  
The Relationship

The effect of spatially variable overstory on the understory light environment of an open-canopied longleaf pine forest

2002 ◽  
Vol 32 (11) ◽  
pp. 1984-1991 ◽  
Author(s):  
Michael A Battaglia ◽  
Pu Mou ◽  
Brian Palik ◽  
Robert J Mitchell
Keyword(s):  
Spatial Variation ◽  
Spatial Patterns ◽  
Longleaf Pine ◽  
Light Availability ◽  
Canopy Structure ◽  
Basal Area ◽  
Pinus Palustris ◽  
Pine Forest ◽  
Large Group ◽  
The Relationship

Spatial aggregation of forest structure strongly regulates understory light and its spatial variation in longleaf pine (Pinus palustris Mill.) forest ecosystems. Previous studies have demonstrated that light availability strongly influences longleaf pine seedling growth. In this study, the relationship between spatial structure of a longleaf pine forest and spatial pattern of understory light availability were investigated by comparing three retention harvest treatments: single-tree, small-group, large-group, and an uncut control. The harvests retained similar residual basal area but the spatial patterns of the residual trees differed. Hemispherical photographs were taken at 300 stations to calculate gap light index (GLI), an estimate of understory light availability. Stand-level mean, variation, and spatial distribution of GLI were determined for each treatment. By aggregating residual trees, stand mean GLI increased by 20%, as well as its spatial variation. Spatial autocorrelation of GLI increased as the size of the canopy gaps increased and the gaps were better defined; thus, the predictability of GLI was enhanced. The ranges of detrended semivariograms were increased from the control to the large-group harvest indicating the spatial patterns of understory GLI became coarser textured. Our results demonstrated that aggregated canopy structure of longleaf pine forest will facilitate longleaf pine seedling regeneration.

Ecosystem service flows in Karst area of China based on the relationship between supply and demand

2021 ◽  
Vol 41 (9) ◽  
Author(s):  
张欣蓉，王晓峰，程昌武，刘世荣，周潮伟 ZHANG Xinrong
Keyword(s):  
Ecosystem Service ◽  
Supply And Demand ◽  
Karst Area ◽  
The Relationship

Exploring Spatial Patterns of Property Crime Risks in Changchun, China

2013 ◽  
Vol 4 (3) ◽  
pp. 80-100 ◽  
Author(s):  
Wei Song ◽  
Daqian Liu
Keyword(s):  
Spatial Patterns ◽  
Hot Spots ◽  
Property Crime ◽  
Ordinary Least Squares ◽  
Neighborhood Characteristics ◽  
Risk Areas ◽  
Gwr Model ◽  
The Relationship ◽  
The City ◽  
Crime Risks

Urban crime has increasingly become a major issue for Chinese cities. Using crime data collected at police precincts in 2008, the main aim of this research is to examine the spatial distribution of property crime which accounted for almost 82% of all crimes in the city of Changchun, and analyze the relationship between the spatial patterns of property crime and neighborhood characteristics. Standardized property crime rates (SCR) were applied to assess the relative risk of property crime across the city. Statistically significant clusters of high-risk areas or hot-spots were detected. A global ordinary least squares (OLS) regression model and a geographically weighted regression (GWR) model were calibrated to explore the risk of property crime as a function of contextual neighborhood characteristics. The analytical results show that significant local variations exist in the relationship between the risk of property crime and several neighborhood socioeconomic variables.

scholarly journals Effect of land use on soil enzyme activities at karst area  in Nanchuan, Chongqing, Southwest China

2014 ◽  
Vol 60 (No. 1) ◽  
pp. 15-20 ◽  
Author(s):  
Q. Li ◽  
Liang JH ◽  
He YY ◽  
Hu QJ ◽  
S. Yu
Keyword(s):  
Land Use ◽  
Land Use Change ◽  
Enzyme Activities ◽  
Soil Enzyme ◽  
Natural Forest ◽  
Karst Area ◽  
Soil Enzyme Activities ◽  
Soil Urease ◽  
Rock Desertification ◽  
Clear Change

The study of soil enzyme activities under different land use is of importance for exploration of the soil quality evolution and its evaluation during the revegetation at karst area in Nanchuan, Chongqing, China. Seven kinds of land use were chosen as subject, aiming at revealing the changes in soil enzyme activities through experimental and statistical analysis. The results showed that different land use significantly influenced the enzyme activities. Soil urease, invertase, catalase and amylase behaved the different change. A descending order of urease activity was artificial forest, natural forest, shrubbery, grassland, slope field into terrace, rock desertification and farmland. As to invertase and amylase, they have no clear change orderliness with land use change. Moreover, no significant change was observed in catalase activity and the lower value was found in natural forest. The above results cannot reflect the land use effect on the enzyme activities. According to the soil enzyme index (SEI), it can be seen that the SEI changed with an order of natural forest > artificial forest > grassland > shrubbery > farmland > slope field into terrace > rock desertification, which can objectively and fully evaluate the land use change in soil enzyme.

Sign in / Sign up

Export Citation Format

Share Document