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1.
Understanding users’ spatial distribution in forest park is crucial for providing visitors with quality recreation experiences and for park planning and management. Utilizing users’ spatial distribution data, this study aims at investigating associations between trail use level and trail spatial attributes, through examining two large urban forest parks (Gongqing forest park and Paotaiwan forest park) in Shanghai, China. Users’ spatial distribution was measured utilizing GPS trackers with the interval of 10 seconds. This study conceptualizes trail spatial attributes as trail metric attributes and trail configurational attributes. Trail metric attributes include trail mean distance to gates, length, width and level of enclosure, which are calculated based on park map and on-site observation. We computed trail configurational attributes utilizing space syntax theory, which comprise measures of global integration, control, and connectivity. Trail connection with features/facilities, visual connection with water and shading are included as covariate variables. In total, we obtained 134 valid samples in Gongqing forest park and 210 valid samples in Paotaiwan forest park for analysis. Multivariate regression analyses indicate that when involving covariate variables, consistently in both parks, a greater trail usage is significantly related to trail shorter mean distance to park gate, trail width wider than 3 meters, higher global integration and higher control values. Collectively, these four trail spatial attributes explained 31.7 % (p < 0.001) and 27.3 % (p < 0.001) of the variances in trail use level in Gongqing forest park and Paotaiwan forest park. These findings provide direct implications to park designers and managers for providing visitors with different desirable social conditions, and ultimately improve users’ experiences and satisfactions. 相似文献
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Spatial dependence and the relationship of soil organic carbon and soil moisture in the Luquillo Experimental Forest,Puerto Rico 总被引:11,自引:0,他引:11
Wang Hongqing Hall Charles A.S. Cornell Joseph D. Hall Myrna H.P. 《Landscape Ecology》2002,17(8):671-684
We used geo-spatial statistical techniques to examine the spatial variation and relationship of soil organic carbon (SOC) and soil moisture (SM) in the Luquillo Experimental Forest (LEF), Puerto Rico, in order to test the hypothesis that mountainous terrain introduces spatial autocorrelation and crosscorrelation in ecosystem and soil properties. Soil samples (n = 100) were collected from the LEF in the summer of 1998 and analyzed for SOC, SM, and bulk density (BD). A global positioning system was used to georeference the location of each sampling site. At each site, elevation, slope and aspect were recorded. We calculated the isotropic and anisotropic semivariograms of soil and topographic properties, as well as the cross-variograms between SOC and SM, and between SOC and elevation. Then we used four models (random, linear, spherical and wave/hole) to test the semi-variances of SOC, SM, BD, elevation, slope and aspect for spatial dependence. Our results indicate that all the studied properties except slope angle exhibit spatial dependence within the scale of sampling (200 – 1000 m sampling interval). The spatially structured variance (the variance due to the location of sampling sites) accounted for a large proportion of the sample variance for elevation (99%), BD (90%), SOC (68%), aspect (56%) and SM (44%). The ranges of spatial dependence (the distances within which parameters are spatially dependent) for aspect, SOC, elevation, SM, and BD were 9810 m, 3070 m, 1120 m, 930 m and 430 m, respectively. Cross correlograms indicate that SOC varies closely with elevation and SM depending on the distances between samples. The correlation can shift from positive to negative as the separation distance increases. Larger ranges of spatial dependence of SOC, aspect and elevation indicate that the distribution of SOC in the LEF is determined by a combination of biotic (e.g., litterfall) and abiotic factors (e.g., microclimate and topographic features) related to elevation and aspect. This demonstrates the importance of both elevation and topographic gradients in controlling climate, vegetation distribution and soil properties as well as the associated biogeochemical processes in the LEF.This revised version was published online in May 2005 with corrections to the Cover Date. 相似文献
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不同温度下圆叶决明降解过程红壤可溶性氮及氮水解酶动态变化研究 总被引:1,自引:0,他引:1
为了探明圆叶决明(Chamaecrista rotundifolia)降解过程果园红壤供氮水平的变化规律,本研究采用模拟培养试验,研究15℃和25℃培养果园红壤硝态氮、铵态氮、可溶性总氮、可溶性有机氮含量的变化及脲酶、蛋白酶、天冬酰胺酶活性的变化。结果表明,圆叶决明降解过程果园红壤4种可溶性氮含量均显著提高,且在培养140 d达到最大值,25℃培养的效果更佳。其中,可溶性总氮、可溶性有机氮和硝态氮含量随时间的动态变化可用三次曲线方程来拟合。圆叶决明降解过程还能显著提高脲酶、蛋白酶和天冬酰胺酶的活性,其中蛋白酶活性和脲酶活性的变化可用指数方程和三次曲线方程来拟合。本研究认为圆叶决明降解过程可提高果园红壤可溶性氮含量,因此可通过翻压圆叶决明提高土壤的供氮水平。 相似文献
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刘更寿 《青海畜牧兽医杂志》2014,(3):18-19
对幼年牦牛断乳后分别在海拔3200m和4229m地区饲养,结果高海拔饲养的牦牛的体重和各项体尺均显著高于低海拔饲养的牦牛。 相似文献
6.
Group housing is claimed to possibly provide horses with a species-appropriate movement possibility, and hence, better welfare. Thus, this study analyzed the daily walked distances of 51 horses held in one group in a “HIT Active Stable” (Hinrichs Innovation + Technik) in Northern Germany by using global positioning system (GPS) technology during a 7 ½-month time span. The daily walking distances of the whole group, as well as newcomers, were investigated. The horses traveled an average of 8.43 km/day. Linear mixed models were applied. The observation day had a significant effect on the daily walking distances (P < .01) due to season and the available area per horse. The age as covariate also had a significant effect (P < .01). The breed had no significant effect (P = .96). No significant differences were found in sex (P = .69), which can be explained by the fact that only mares and geldings were investigated, which do not show increasing locomotion caused by sexual behavior as stallions do. On six of the first nine days, new horses moved significantly more compared to the remaining 24 of the 30 observation days directly after individuals’ inclusion. This is probably due to more exploration and rank-fighting behavior. Similar walking distances were seen among the horses on the single observation days because all horses had to travel the same distance to reach resources. Further, it is suspected that not all horses can sufficiently live out their urges to move, especially in winter, when pasture is inaccessible. 相似文献
7.
基于高程的偏度参数统计的LiDAR数据滤波对地形起伏城区滤波适应性不强的弱点,对该方法进行了改进,提出了结合渐进形态学开运算和偏度平衡法的LiDAR数据滤波方法,该方法的原理就是将所有引起高程的突变转换成全由植被、建筑等非地面点引起,而不是由地形高程引起的,这个转换的中间量就是高差,即将高差作为偏度系数的统计对象.并通过实验验证了该方法的合理性,实验结果表明,改进的方法不仅延续了参数统计法无需阈值的优势,而且对城区滤波更具适应性、合理性和稳定性,能够明显地提高滤波精度. 相似文献
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In order to help tourists choose satisfying scenic spots, content hotels, convenient lines and convenient vehicles, vehicle monitoring control and scheduling management system in a scenic area is presented, which dispatches vehicle by appointments and the statistic of tourists at a sight spot and recommends the tour line by broadcasting in vehicle. Vehicle monitoring control and scheduling management system in a scenic area, a integrative vehicle management system, is an integration of GPS, GIS, trunked radio system, a management system of booking room and a tourist statistic system at a sight spot. 相似文献