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Transformation and assessment of Chinese pine pure plantations for soil and water conservation in western Liaoning Province,P. R. China 被引量:1
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作者 曾德慧 姜凤岐 +2 位作者 郭浩 范志平 杜晓军 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第2期127-134,i002,i003,共10页
Western Liaoning Province is characterized by huge areas of lowly-efficient Chinese pine (Pinus tabulaeformis Carr.) pure plantations. How to transform these plantations has become an increasingly significant manageme... Western Liaoning Province is characterized by huge areas of lowly-efficient Chinese pine (Pinus tabulaeformis Carr.) pure plantations. How to transform these plantations has become an increasingly significant management problem. In this study, the authors summarized the approaches, which are based on close-to-nature silvicultural system, to transform the pure pine plantations. Native broadleaved trees were planted in three methods: 1) after strip clearcutting, 2) after patch clearcutting; 3) on the open forestland and the forest edge. The transformation targets and the selection of tree species were expatiated in this paper. The key techniques and their application conditions for each method were analyzed and discussed. Through investigation and contrastive analysis, the assessment was made to the stands transformed by strip method. Results showed that the mixed stands at 16 years after transformation had an obvious layered structure and the species richness of understorey vegetation increased by 23.5%–52.9%. Soil enzyme activities of urease, phosphatase and sucrase increased by 6%–142%, 46%–99% and 31%–200%, respetively. Moreover, the transformed stands could effectively control the occurrence of pine caterpillars in plantations. Consequently the transformations enhanced the function of soil and water conservation. Keywords Pinus tabulaeformis - Monoculture - Transformation - Principles and methods - Assessment CLC number S791.254 - S727.22 Document code A Foundation item: This research was supported by grants from the Chinese Academy of Sciences (KZCX3-SW-418), National Natural Science Foundation of China (30100144), and National Key Technologies R & D Program of China (96-007-01-06).Biography: ZENG De-hui (1965-), male, Ph.D. professor in the Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, P. R. ChinaResponsible editor: Zhu Hong 展开更多
关键词 Pinus tabulaeformis MONOCULTURE TRANSFORMATION Principles and methods ASSESSMENT
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柑桔旱害发生原因及抗旱措施 被引量:1
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作者 黎明 《四川果树》 1997年第4期45-45,共1页
今年是我市连续遭受干旱的第四个年头,干旱时间之久,程度之重,为四年来之最.从7月下旬到9月中旬,全市绝大部份地区都未降雨,持续高温达50多天,给水果生产带来了较大影响,据调查统计,全市约5千万株果树受旱,占水果总株数的70%以上,其中... 今年是我市连续遭受干旱的第四个年头,干旱时间之久,程度之重,为四年来之最.从7月下旬到9月中旬,全市绝大部份地区都未降雨,持续高温达50多天,给水果生产带来了较大影响,据调查统计,全市约5千万株果树受旱,占水果总株数的70%以上,其中干枯死亡400多万株,果苗于死40万株,今年春夏高换柑桔树70万株中约10万株死亡,成活的高接树亦大部份抽不出梢.预计今年全市水果减产40%以上,直接经济损失为2.5亿元,象这样严重的果树旱灾实属历史少见,南充常年均发生不同程度的春、夏、秋旱灾,柑桔受旱减产的年份也较多.因此,针对我市旱灾发生情况及柑桔生长发育规律,探讨对策,采取抗旱措施,增强果树的抗旱能力,夺取高产,显得极为重要.下面简单分析一下我市柑桔旱害发生的原因及影响因素,提出一些抗旱措施,供广大果农参考. 展开更多
关键词 柑桔类果树 干旱 发生原因 改土保水 修蓄水池
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外国的旱地农业
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《中国农村科技》 2005年第9期46-46,共1页
关键词 旱地农业 改土保水工程 印度 美国 保持耕作 加拿大 积雪管理 以色列 节水灌溉
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Evaluation of Infiltration Capacity and Water Retention Potential of Amended Soil Using Bamboo Charcoal and Humus for Urban Flood Prevention
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作者 Rei Itsukushima Kazufumi Ideta +2 位作者 Yuki Iwanaga Tatsuro Sato Yukihiro Shimatani 《Journal of Earth Science and Engineering》 2016年第3期150-163,共14页
In Japan, floods occur frequently in urban areas because non-infiltrating areas are seeing increased urbanization. To prevent floods, urban basins must improve the infiltration capacity and water retention of the whol... In Japan, floods occur frequently in urban areas because non-infiltrating areas are seeing increased urbanization. To prevent floods, urban basins must improve the infiltration capacity and water retention of the whole basin. There are several basic technologies for river basin management, such as infiltration trenches or rainwater storage. However, a method of soil amendment that prevents flood disasters has not been established. This study aims to evaluate the infiltration capacity of soil amendments using bamboo charcoal and humus. A constant-head infiltration test and rainfall simulation were conducted to evaluate the properties of the soil amendments. The constant-head infiltration test's results showed that soils mixed with 30% humus had the greatest potential for influencing initial and final infiltration rates, and the more the mixing rates of bamboo charcoal and humus were increased, the higher the water retention capacity. The results of the rainfall simulation showed that soils mixed with 30% humus had the highest final infiltration rates and lowest multiplication spillage. To reduce the runoff volume using soil amendment technology, it is important to delay overland flow, and the hydraulic properties of the soils mixed with bamboo charcoal and humus were as effective as those of granite soils. 展开更多
关键词 Soil amendment infiltration capacity urban flood prevention constant-head infiltration test watering experiment.
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