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StudysiteThestudysiteislocatedintheeasternslopeofDaxing'anMountains(47"25'~49'37'N,119'37'-122"45'E),whichbelongstotheBalinForestryBu-reauofNeiMenggol.ThemaintopographyislowermountainsandhilIs.Thealtitudeis4oo~1ooom.Theannualaccumulativetemperature(>=1oC)isabout1845oC.AnnuaIprecipitationis42omm.Annualaveragetemperatureis-15t.Thefrost-freeperiodis97d.lnthisarea,thezonalsoilisbrownconiferousforestsoil,theothertypeofsoilismeadowsoilandbogsoiI.ThemainfundamentaIrockisgrinite.ThebasaItisse… 相似文献
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Based on the plot data from the investigation and the theory of forest ecology and ecological system, the site classification
of the eastern forest region of Daxing’an Mountains was made by mean of mathematical method. The main factors were slope,
thickness of soil layer, slope position and slope aspect. Grades of slope were used as the division standard for site type
group. The slope aspect, slope position and thickness of soil layer were used as the division standards for site type. Altogether
7 site type groups and 15 main site types were determined the region. It provided reliable fundamental basis for the reasonable
management and planting design in the area.
Responsible editor: Zhu Hong 相似文献
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分级造林能有效地减小杜仲林分个体间差异 ,提高林相整齐度。以苗高为指标 ,1年生杜仲实生苗的分级标准是 : 级苗高不低于 1.0 m; 级苗高 0 .6~ 0 .99m; 级苗高 0 .6 m以下 相似文献
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防护林体系对噪声的影响 总被引:1,自引:0,他引:1
利用人工设置的噪声 ,在空旷、林带、片林进行了噪声强度测定 ,研究出噪声强度在空旷地、不同结构的林带、不同树种组成的林分中的变化情况 ,提出了防止环境噪声应采取的措施。 相似文献
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1ThisStudyisoneoftheprojectssuportedbyNaturalScienceFundationofHeilongjiangProvinceIntroductionSitoindexisaconvcnientstcptoxtardtl1eultin1ategoaiofpredictingtheproductioncapability'offorcstlwt;anditisausefuldircctmeasuresforapotentialexpetionparadigmintcn… 相似文献
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沙质岸黑松海防林更新属于改造技术的研究 总被引:2,自引:0,他引:2
应用典型调查与定位试验相结合的方法,探讨了黑松海防林低质低效的形成原因,据其成因将这些林分划分为5种类型,提出了相应的改造意见,并编制出黑松海防林密度管理表。通过更新造林和抚育技术试验,提出了较合理的更新方式,主要有林冠下更新造林、留伐桩萌芽更新、隔行更新造林、人工促进天然更新、带状更新等,其中,带状更新适于在林分条件相对较好的情况下应用,其它几种更新方式较适于低效林的更新改造;采用稀疏林补植、林下种植灌木或绿肥压青、封禁保护枯落物等技术,可有效地改善林分状况。 相似文献
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The Huanglong Mountain forest zone is one of the major natural secondary forest zones in the southern Loess Plateau in Shaanxi
Province, China. Since 1950, a mode of fully closed hillside afforestation (FHA) has been applied in the forest. On some special
sites, the forest age exceeds 80 years. Pinus tabulaeformis forests form the most important vegetation cover in the warm temperate regions of China. Similarly, populations of P. tabulaeformis are dominant in existing forest ecosystems. Quercus liaotungensis, Syringa oblata, Populus davidiana, Prunus davidiana, Betula platyphylla and Toxicodendron vernicifluum can be occasionally found in the tree layer and shrub species are abundant. Based on the data collected from 31 plots and
93 soil samples, the state of health of the forest ecosystem is discussed and the appropriate FHA age has been determined.
Twelve indices representing vegetation and soil properties in natural, secondary P. tabulaeformis forest ecosystems were generated by sensitivity analysis and an assessment index system for the FHA mode was established.
According to the equal distance method, a clustering technique and five grades of an integrated index for evaluating the FHA
mode were compartmentalized. The effect of the FHA mode on natural secondary P. tabulaeformis forests was evaluated by an integrated index method with the aid of an analytical hierarchy process (AHP). The results are
as follows: values of the integrated index in the FHA mode of 16, 25, 30, 45, 60 and 75 year old stands were 7.25, 6.88, 7.82,
5.51, 4.78 and 2.79 respectively. With an increase over age of the FHA stands, the effect of the FHA mode deteriorated. We
conclude that natural forests should not be protected in the FHA way after 45 years. At that stage, mixing suitable tree species,
selection cutting and other silvicultural and management measures should be adopted.
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Translated from Acta Ecologica Sinica, 2007, 27(1): 288–295 [译自: 生态学报] 相似文献
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五桂山位于广东中山市东南沿海,其东南坡向的海岸带迎风坡性质明显。在造林4年和1年的两块林地上,分别建立两条跨越迎风坡和背风坡的固定样带,对样带的调查研究结果表明:只要实行高强度营林措施,适地适树,海岸带坡地退化生态系统是可恢复森林植被的;根据参试树种的早期生长表现,大叶相思、西南桦、台湾相思、米老排、红锥、厚荚相思、海南蒲桃等的生长速度较快,海南红豆和云南石梓的生长速度则较慢,这两种树种不太适宜在迎风坡造林;在采用相对密植的前提下,林分郁闭前迎风坡造林树种的死亡率高于背风坡,郁闭后则背风坡较高,为尽快形成森林小环境,建议迎风坡的造林密度应大于背风坡;在造林措施相同的条件下,背风坡林木生长量、物种多样性和林分质量明显优于迎风坡,说明海岸带坡向因子对植被恢复具有显著影响。 相似文献
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中国林蛙是东北林区栖息的重要野生经济动物,是发展林下经济的主要项目。根据延边地区的森林环境和野生中国林蛙资源状况,将该区域适宜林蛙养殖的林地划分为6类,对人工放养量提出了参考数据,并应用电脑技术制作了分布图。 相似文献
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建立了森林生态经济区域分类的Kohonen神经网络分类模型,对广东省森林生态经济系统进行了分类,取得了较为理想的分类结果。模型不需人工确定指标的权重,具有自学习,动态分类的优点,为森林生态经济区域分类提供了一种有效方法。 相似文献
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马尾松天然林立地质量评价 总被引:2,自引:0,他引:2
利用二类调查固定样地资料 ,分析了马尾松天然林上层木平均高、胸径与年龄三者之间的关系。结果表明 :年龄在决定马尾松天然林上层木平均高时意义不大 ,而上层木平均高与胸径的相关性密切 ,符合Richards方程。故采用上层木在一定胸径 ( 35cm)时的高度值表示立地指数。讨论了这种评价方法的理论基础、精度及其天然异龄林经营实践中的意义 相似文献
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Afforestation and forest management can increase carbon stocks and account for emission reduction according to the 相似文献
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影响北方地区造林质量的若干因素与建议 总被引:1,自引:0,他引:1
近年来,我国每年的人工造林面积都在420万hm2以上,居世界首位。但有些地方对造林质量并没有引起足够重视,营造大面积的纯林,造林质量总体水平不高,容易引发大面积的病虫害。主要原因是营造林中未严格贯彻"适地适树"原则、后期抚育管护不到位和良种化水平不高等。本文针对这些问题提出了解决措施与建议。 相似文献
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杉木萌芽更新造林技术初探 总被引:1,自引:1,他引:0
分析了影响杉木萌芽更新造林的主要因子后,提出了萌芽更新造林的技术要点,以及提高萌芽杉木林生产力的措施。以利第2代杉木林能够持续健康的发展。 相似文献
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Qiang Xiao 《Journal of Sustainable Forestry》2019,38(5):427-441
Ecological degradation is a key factor limiting sustainable development. Artificial afforestation has chiefly been used to combat it, especially in China. In order to contain rocky desertification and ecological and environmental degradation in Southwest China, the Government of China has planted 6000 km2 of trees in this region since the year 2000. Yet, the resultant water consumption of artificial afforestation has had a significant influence on water resource supplies in Southwest China, and its internal mechanisms remain largely unclear. Studies in Southwest China have shown that artificial afforestation has degraded the natural water balance in Yunnan Province because of the elevated evapotranspiration levels associated with manmade forests. Accordingly, such increases in evapotranspiration have disturbed the water resource balance of the region. It is been suggested that natural restoration practices should therefore be encouraged in this region or plants that consume less water should be grown in place of artificial afforestation. This study sheds some light on the cycles of local water resources and the stimulus of climate change to access ways by which to afforest Yunnan Province sustainably and successfully. It also presents a strong argument on how to use water resources to enable vegetation construction initiatives in Yunnan Province while avoiding potential ecological risks. 相似文献