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In this paper,the root system and their associated effect of mixed forest of Cunninghamia lanceolata and Sassafras tsumu at eight-year-old were investigated and analyzed.The results showed that Sassafras tsumu might play a important role in improving the root system of Cunninghamia lanceolata growth due to the single root weight of Cunninghamia lanceolata in mixed forest of Cunninghamia lanceolata and Sassafras tsumu was evidently more than that of Cunninghamia lanceolata in pure forest,and that there were different mixed effects in mixed forest of Cunninghamia lanceolata and Sassafra tsumu in different slope situation,which meant that the associated effect was better in higher slope situation than in lower slope situation,and which reflected in the effect of Sassafra tsumu to the height and D.B.H.growth of Cunninghamia lanceolata.This Study indicated that the associated effect was positively related to the effect of roots system. 相似文献
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通过实地测量、数据收集与资料分析,计算福州市五个不同类型城市绿地区域植被群落多样性,从降温效益、增湿效益、遮光效益和挡风效益四方面探究该区域生态效益的综合评价值。运用定性分析和相关性分析等方法,对不同类型绿地植被物种多样性与生态效益的相关关系进行分析与研究。结果表明:(1)福州市不同类型绿地植被群落总体物种多样性指数大小排序为公园绿地(1.3)商业区(1.18)居住区(1.04)工业区(0.86)道路区(0.57);(2)不同类型绿地植被生态效益大小排序为公园绿地(0.98)商业区(0.57)居住区(0.49)工业区(0.31)道路区(0.03);(3)不同类型绿地植被生态效益的差异性与群落总体多样性指数存在显著正相关,且相关系数为0.958。该研究从植被群落物种多样性角度,对福州市生态效益较差的绿地类型提出综合改造建议,以期在城市绿地植被的规划和发展方面提供理论参考和依据。 相似文献
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不同夜间温度对小麦旗叶光合作用和单株产量的影响 总被引:13,自引:3,他引:13
本文用不同夜间温度连续处理抽穗开花后的小麦植株,对旗叶的光合作用和单株产量进行了比较研究。结果表明夜间低温能明显延长叶片叶绿素含量缓降期和光合速率高值持续期,从而增加叶片的叶源量,提高产量。经计算缓降期延长一天,可使单株产量和千粒重分别提高2.0-2.5%和1.5-2.0%。夜间高温处理植株效果相反。试验进一步研究 相似文献
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粤甜9号是广东省农科院作物研究所选育出的黄粒甜质玉米杂交种.2002~2003年在生产试验中表现出高产、优质、适应性广及抗逆性强等特点.介绍了配套的栽培措施.该品种属大穗型超甜玉米. 相似文献
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祁门县竹林7565 hm2,每年可向社会提供竹材150~200万根,可为社会创造近2000万元直接经济效益.经营好的竹林主要分布在凫峰、大坦、祁山、安凌等毛竹重点乡镇.2008年1月的冰雪和持续低温,毁坏了竹区大面积竹林.为尽量减少灾害性天气给竹区林农带来的损失,造林时应采取有效措施,如营造混交林、进行毛竹林钩梢等技术措施,提高林木抗自然灾害的能力. 相似文献
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