Showing papers in "Journal of Zhejiang A & F University in 2017"

Research on scenic beauty estimation (SBE) of landscapes of Xiazhu Lake National Wetland Park based on SBE method.

Abstract: Evaluating the scenic beauty of wetland park landscape can provide a scientific basis for completing the planning development and improving the management strategy. Taking Xiazhu Lake National Wetland Park as the research object, 43 landscape samples were collected and their scenic beauty estimation numerical values were calculated by scenic beauty estimation (SBE) evaluation method. A model of linearity relationship between the scenic beauty estimation and determinants was established as follows:y=-5.071+0.358c2+0.356c4. The results showed that c2 (ornamental), c4 (comparison and association) had comparatively significant impact on the scenic beauty while c1 (the principal and the subordinate, and emphasis), c3 (balance) and c5 (proportion and scale) had less impact on the scenic beauty. According to the result, several suggestions for developing Xiazhu Lake National Wetland Park are put forward.

Research and construction of web crawler based forest management knowledge collection system.

Abstract: Accurate Internet access to forest management information can be obtained through the construction of a data collection system for forest management. Based on an analysis of the data collection, system process, system module and database were designed, rules governing web crawlers were improved and delimited, and workflow and algorithm of web crawlers were explored. This system summarized and analyzed the characteristics observed from webpages featuring forest management, and served to identify those collected data contents with an eigenvector of forest management. Information about forest management was also denoised by this system; information was extracted through intelligence match, and repeated information about forest management was eliminated through fingerprint recognition by Euclidean distance. The experiment results indicated that this data collection system for forest management featured high subject relevance, high accuracy, and low repetition rate. Therefore, it can satisfy the need of the forest management decision support system.

Fire disturbance and environmental factors for the undergrowth in a Pinus tabulaeformis forest

Abstract: To study the influence of fire disturbance and environmental factors on undergrowth vegetation changes in a Pinus tabulaeformis forest, burned areas of an artificial P. tabulaeformis forest in Liaoheyuan National Forest Park of Pingquan County, Hebei Province were used as research objects. The burned forest was divided into three levels according to the degree of burn:mild, moderate, and severe. And three repeated plots were set. Non-burned forests near the burned area were also used for control plots. A redundancy analysis (RDA) was conducted on undergrowth vegetation and environmental factors in the three degrees of the burned area and the non-burned forest. Analysis also determined the richness index (R), diversity index (H), and evenness index (J). Results showed that undergrowth regeneration after fire was largely influenced by tree mortality rate and slope aspect, but slope and slope position had little effect on important herbs. The importance value for herbs and shrubs showing different degrees of change after fire:compared to control plots the severe burned area had a sharp increase in the number of herbaceous species from 15 to 26 with the number of shrub species increasing from 3 to 6. With an increase in fire intensity, R and H showed an overall increase (P < 0.05); whereas, J decreased (P < 0.05). Thus, growth and changes in undergrowth vegetation after fire were jointly affected by fire and topographic factors with fire being conducive to regeneration of undergrowth vegetation partly.

Greenhouse soil properties and vegetable yield with dead pig and bamboo biochars

Abstract: A field experiment was conducted to determine the effect of dead pig (DPB) and bamboo (BB) bio-chars as well as their application patterns on yield and nitrogen (N) content in vegetables and on soil properties (pH, electrical conductivity, and N content) in an Ipomoea aquatica-Brassica chinensis rotation system at Banqiao Town, Lin'an City, Zhejiang Province, China. Treatments included (1) a control (no biochar); (2) one application of 20 t·hm-2 of 20-0-BB and (3) 20-0-DPB prior to the first I. aquatica crop; and two applications of biochars with 10 t·hm-2 being applied prior to the I. aquatica season and the remaining biochars[(4) 10-10-DPB or (5) 10-10-BB] being applied prior to the B. chinensis season at an application rate of 10 t·hm-2. The treatments were laid out based on randomized complete block design with four replications. The plant shoots of I. aquatica and Brassica chinensis in each plot were harvested after growth for 65 and 40 days, respectively. At each harvest time, five plants and five soil cores (0-200 mm) respectively from each plot were randomly collected and bulked for chemical analysis. Results showed that in the I. aquatica crop season, the 20-0-DPB treatment significantly increased (P < 0.05) the I. aquatica crop yield and soil pH. Also, the 20-0-DPB and 10-10-DPB treatments significantly increased (P < 0.05) yield of B. chinensis; whereas, the 20-0-BB and 10-10-BB treatments significantly decreased (P < 0.05) the I. aquatica crop yield. Additionally, the 20-0-DPB and 20-0-BB treatments significantly increased N (P < 0.05) in roots of I. aquatica Forsk but not in B. chinensis. The 10-10-DPB treatment significantly increased (P < 0.05) B. chinensis root N. Finally, biochar treatments had no significant effect on soil nitrate or vegetable shoot N. In conclusion, the dead pig biochar was more effective than the bamboo bio-char for increasing soil pH and vegetable yield with one application of dead pig biochar at 20 t·hm-2 appearing to be better than two split applications.

Evaluation and sustainable development on ecological service value for urban green space system in Hangzhou City

Abstract: Based on the concepts of ecological services value index (IESE), economic development index (IED) and social benefit index (ISB), the research used the method of entire-array-polygon diagram index to evaluate the ecological services value of urban green area in Hangzhou between 2005 and 2014 and calculate the comprehensive index of sustainable development of ecological service. The results showed that the total ecological services value of urban green space system in Hangzhou had increased from 1 440.67×106 RMB in 2005 to 2 463.22×106 RMB in 2014; the annual comprehensive indexes of sustainable development of ecological service in these ten years were 0, 0.008, 0.107, 0.341, 0.105, 0.781, 1.020, 0.834, 0.772 and 0.836 respectively. The ability of sustainable development had been fluctuating, showing the trend of increasing first and then decreasing. The relationship among ecological services value index (IESE), economic development index (IED) and social benefit index (ISB) could be described in linear equation: S＝0.912IESE-0.742IED+0.431ISB-0.084. The assessment of the ecological services value of urban green area and the research on sustainable development in Hangzhou will provide reference for optimizing the pattern of urban green space, and sustainable and coordinated development of ecology and economy.