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文章以九寨沟县干旱河谷区域为研究对象,分析干旱河谷区气候、植被、土壤、造林现状与成效影响因素,从区域的生态特点出发,遵循自然规律,总结干旱河谷区造林应遵循的基本原则,扼要归纳了干旱河谷区造林技术要点. 相似文献
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针对会泽县大海乡干热河谷地区在选择造林树种方面存在的问题及多年造林都没有取得成效的实际,依据干热河谷地区的自然条件,结合大海乡的发展需求,通过实验总结提出了大海乡干热河谷地区造林树种选择及营林措施的相关技术建议:在干热河谷地区造林,恢复干热河谷的植被,改善干热河谷地区的生态环境及生存环境. 相似文献
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干热河谷是造林困难区域,过去造林遵循以树、草种的选择和造林时间、造林方法的选下来适应或逃避不利因素.但在经济条件制约下,采用现代育苗技术和造林方法受到限制,同时可选树、草资源十分有限,长期以来严重影响造林工作的进行和造林质量的提高.作者提出通过整地和防渗处理,人工引起并拦蓄地表径流,改善林木生长的上壤水分条件,以达到林木在干旱区域正常生长. 相似文献
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在岷江上游干旱河谷区通过设置不同海拔梯度,对土壤水分、岷江柏生理生化及生长指标进行了分析,旨在探索干旱河谷区主要造林树种对逆境的响应,为这一地区岷江柏人工林的营造提供理论和技术支撑。研究结果表明:随海拔的升高,岷江柏的光合速率、水分利用率、SOD活性、丙二醛(MDA)含量、可溶性糖含量、脯氨酸含量、苗高和地径年生长量的蒸腾速率、可溶性蛋白含量表现为先升高再下降的趋势;而POD活性和叶绿素含量则是随着海拔的升高呈不断下降的变化趋势。从其生长指标和生理指标来看,岷江柏在海拔2 200 m~2 300 m之间生长最好。因此,在该区营造人工岷江柏林的时候,应该优先选择这一地段。 相似文献
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人工幼林蒸腾规律的研究 总被引:5,自引:0,他引:5
对刺槐、紫穗槐、河北杨、白榆、侧柏等新造人工幼林生长期蒸腾的研究表明:蒸强日间均值12~14时最大,0~2时最小,凌晨5~6时渐升。昼间均值顺序是:紫穗槐>刺槐>河北杨>白榆>侧柏。回归建立的五种树种蒸强与环境因子关系的非线性回归方程,相关系数大于0.77,差异极显著。五个方程偏相关系数顺序是:光照强度>气温>风速>相对湿度。蒸腾耗水量月均值顺序是:刺槐>紫穗槐>河北杨>白榆>侧柏。 相似文献
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采用涡度相关技术对华北低丘山地30年生栓皮栎-刺槐-侧柏人工混交林生态系统进行连续2年的碳通量观测。结果表明:人工混交林净生态系统碳交换(NEE)的年际和季节变化都很明显,但日变化只在生长季(4—10月)才变得显著。2006和2007年人工混交林NEE的变化范围分别在-27.1~8.1和-24.4~9.8gCO2·m-2d-1,最大月平均CO2吸收量分别出现在5月和7月。生长季净碳吸收约占全年的96%。人工混交林是较强的碳汇,2006和2007年净碳吸收量分别为549.1和445.4gC·m-2a-1。春季干旱是2007年人工混交林净碳吸收显著下降的主要原因。 相似文献
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泸定县大渡河干旱河谷区营养袋育苗与雨季造林技术试验 总被引:1,自引:0,他引:1
泸定县大渡河流域属干热干旱河谷地带,常规育苗造林成活较差。本文使用云南松、辐射松、岷江柏3种树种开展营养袋育苗和大田育苗进行对比试验,试验表明3种树种的营养袋育苗较常规育苗在出苗率、1 a生苗高、地径、须根长度、须根数量等方面,其增幅都在20%~71%间,差异显著;同时在对三种树种采用雨季营养袋造林和常规裸根造林对比试验中,结果表明前者较后者在当年成活率,年均高生长、年均地径生长,3 a保存率,都有着显著差异,且营养袋造林成活后抗逆强、生产成本低、经济效益显著,值得广泛推广。 相似文献
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在延安对刺槐、油松、侧柏纯林及刺槐 侧柏、刺槐 油松混交林等几种黄土高原主要人工林群落外貌结构、林下植物多样性特征进行了研究.结果表明:混交林群落外貌结构较为复杂,林下植物群落类型各不相同;林下植物的Simpson多样性指数和Shnnon-wiener多样性指数分别为0.902 57~0.674 88和2.012 88~1.479 67,刺槐 油松林最高,16年生刺槐纯林最低;32年生刺槐纯林林下植物优势度最高者是糙隐子草,16年生刺槐纯林则为牡蒿,其它林型都是铁杆蒿;本地区选择防护林类型时,应优先选择刺槐 油松或刺槐 侧柏混交,对已有的成熟或衰退刺槐纯林可采取择伐萌蘖抚育,并间植油松或刺柏,形成针阔混交林. 相似文献
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在岷江上游干旱河谷岷江柏木幼林地经过连续4 a利用雨季种植绿肥压青,增加土壤肥力,提高水分利用率,促进幼树生长研究。结果表明:(1)种植红豆草的土壤0~40 cm含水量旱季增加3.68 g·kg-1,0~20 cm土壤容重降低0.07 g·cm-3;种植草木樨土壤0~40 cm含水量旱季增加4.18 g·kg-1,0~20 cm土壤容重降低0.05 g·cm-3;种植沙打旺土壤0~40 cm含水量增加2.46 g.kg-1,0~20 cm土壤容重降低0.18 g·cm-3。(2)种植绿肥压青,土壤有机质增加0.37 g·kg-1~0.55 g·kg-1,土壤CaCO3含量下降0.66 g·kg-1~1.36 g·kg-1,有效氮增加4.5 mg·kg-1~18.5 mg·kg-1,有效磷含量增加1.0~3.46 mg·kg-1,CEC比对照增加0.54~0.58mg.100g-1。(3)种植红豆草、草木樨、沙打旺绿肥压青对岷江柏木树高、地径生长有显著的促进作用,尤其种植红豆草的岷江柏木幼树生长最好,高、径生长为对照的1.7倍和1.6倍。 相似文献
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Water is the key factor in vegetation growth in a loess area. Researchers have been keen on the study of tree transpiration
for a long time. To provide a scientific basis and practical instruction for vegetation reconstruction and recovery in a loess
area, the paper measured and calculated the water consumption of potted Platycladus orientalis, Robinia pseudoacacia, Armeniaca vulgaris and Pyrus hopeiensis separately during the growing season (from Apr. to Nov.). The four were the main afforestation species in a loess area of
western Shanxi based on the principle of water balance. Using data on soil water dynamics and the range of available moisture
on potted mature trees, the relationship between water supply and consumption and soil moisture availability and deficit state
were analyzed. Several conclusions are listed as follows: 1) In the dry year (2002), during the growing season the precipitation
was 430.7 mm and the water consumption of potted trees was from 430 to 490 mm. More water consumption and less available water
supply occurred, showing a serious water deficiency. In the rainfall-rich year (2003), during the growing season the precipitation
was 870.2 mm and the water consumption of potted trees was from 480 to 515 mm. Due to the uneven distribution of rainfall,
the water budget balance was slightly affected in May and November. 2) The curves of soil water content of different species
had similar annual changes, although the trends were different in the same month, and those of the same tree species in different
test plots also had different trends in the same month. 3) Non-available soil water content of Platycladus orientalis, Robinia pseudoacacia, Armeniaca vulgaris and Pyrus hopeiensis was less than 8.0%, 8.4%, 9.2% and 9.7% respectively, which indicated that Pyrus orentalis used water more efficiently than the others. In the dry year (2002), for several months, soil water content of potted trees
was lower than its threshold value for non-available soil water content, which could influence the healthy growth of trees.
After supplements of precipitation of winter in the year and spring in the next year, soil water content was higher than the
lower limit of soil readily available moisture content, which implied that a balance between inter-annual water supply and
consumption could be maintained.
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Translated from Scientia Silvae Sinicae, 2006, 42(9): 18–23 [译自: 林业科学] 相似文献