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为了探索辽西地区油松混交林与纯林土壤理化性状的差异,开展了几种油松混交林与油松纯林林地土壤理化性质对比分析,结果表明,油松与其他树种混交后可以降低土壤容重、提高土壤孔隙度,增加林内枯落物厚度。混交林处理各项指标与纯林有显著差异,其中地面枯落物厚度以油松+山杏混交林最厚,为2.8 cm;容重以油松+刺槐混交林最轻,为1.187 g·cm-3;孔隙度油松+刺槐最大,为56.35%;土壤有机质含量以油松+刺槐处理最高,为20.1 g·kg-1;全氮含量各混交林处理比油松纯林提高了0.23~0.36 g·kg-1,差异极显著;全磷含量各混交林处理高于油松纯林但是差异不明显;全钾含量混交林处理均高于油松纯林,其中油松+蒙古栎混交林、油松+山杏混交林2个处理极显著高于油松纯林,油松+刺槐混交林与油松纯林未达到显著性差异。 相似文献
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半干旱地区油松纯林发行成混交林效益分析 总被引:2,自引:0,他引:2
半干旱地区大面积的油屯林,不仅生产力水平低、抗性差,林分的涵养水源、防止水土流失等重要生态也因林分结构单一,缺乏灌木覆盖而不尽理想。为改善林分生态条件,提高林林生长量和林分的综合效益。于1983年分别在凌源市、喀左县、建平县对28年生的油松纯林进行了发行试验。结果表明,造反刺槐、沙棘、柠条、黄想等阔叶树种,在带状皆伐的砍伐囊上造林,经多年研究效果显著。油昆交林与油屯林相比,相对湿度提高0.2%~2 相似文献
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为改善阜新地区林分生态条件,控制松毛虫危害,促进林木生长,在小区试验研究基础上,1995—2000年,6年间在阜新地区的28个乡镇、10个国有林场松毛虫发生的常灾区幼林中进行油松纯林改造成混交林技术推广,共推广15 333hm2,实际栽植阔叶林、灌木4 800hm2,成活率85%左右,保存率在80%以上。经济、社会效益十分显著。 相似文献
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阜新地区油松纯林改造效益分析 总被引:2,自引:1,他引:1
在阜新市细河区水泉镇塔子沟流域进行油松纯林改造工程试验,结果表明,油松纯林改造具有可观的生态效益和经济效益,尤其是在松毛虫的防治上,是最理想的防治措施,自改造以来,该区域的松毛虫基本上得到了控制。 相似文献
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油松沙棘混交林土壤酶活性状况的研究 总被引:4,自引:0,他引:4
通过对油松沙棘混交林土壤酶活性状况的研究,初步探索了混交林与纯林在土壤物质转化上的不同,对揭示混交林的增效机理具有一定意义。 相似文献
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混交林土壤养分效益的初步分析 总被引:2,自引:0,他引:2
通过对抚顺地区人工落叶松阔叶混交林、落叶松纯林、天然次生林等林地的土壤养分进行分析,混交林与纯林相比,缓解了酸化作用,增加了土壤有机质和速效磷的含量,同时对各类林地进行综合评价,表明在维护土壤养分平衡功能方面,由高到低依次为天然次生林、混交林、荒山、落叶松纯林,说明局长 人工针阔混交林更有利于生态平衡。 相似文献
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通过对油松纯林进行混交改造试验,比较了混交林在改善林间气候、调节林木生长的效果,结果表明:改造成混交林后可以加大林木生长、提高林间单株蓄积量,降低林间温度、提高林间相对湿度;以油松+紫穗槐混交林树高最大,达8.78 m;平均胸径以油松+小叶锦鸡儿混交林最大,达12.26 cm;单株平均蓄积量以油松+小叶锦鸡儿最大,为0.045 2 m^3;改造成混交林后,相对湿度有所提高,温度下降,以油松+小叶锦鸡儿的降温效果最明显,比纯林下降了3℃。 相似文献
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胡桃楸落叶松纯林与混交林中根际土壤的养分特征(英文) 总被引:6,自引:0,他引:6
与非根际土壤相比较,研究了胡桃楸落叶松纯林与混交林中根际土壤pH值、有机质及氮 、磷、钾等养分元素的特征。结果表明:各林分中,除胡桃楸纯林外,根际土壤的pH值均不 同程度低于非根际土壤;除混交林中落叶松根际土有机质含量略低于非根际土外,根际土壤 有机质含量均高于非根际土壤;根际土壤存在氮的相对累积,磷和钾在根际则具有一定的亏 缺趋势,其程度与树种相关;各林分下,氮、磷、钾在根际中均得以活化,表现为根际土壤 速效氮、磷、钾含量偏高;混交林中落叶松根际速效氮含量明显高于其纯林,而混交林中胡 桃楸根际速效磷、钾含量明显高于其纯林。 相似文献
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根据生态经济学、环境经济学和资源经济学的原理,使用替代和模拟评价方法初步估算辽西山地油松混交林和纯林的生态经济效益.结果表明,辽西油松混交林生态经济效益之和为30.03亿元,辽西油松纯林生态经济效益为17.49亿元.油松混交林各项生态效益、经济效益均高于油松纯林.其中油松混交林比纯林涵养水源效益增加5.82亿元,保肥效益增加3.00亿元,制氧效益增加1.79亿元,防治病虫害效益增加0.02亿元.混交林各项生态效益之和较纯林增加10.82亿元,经济效益之和较纯林增加1.72亿元. 相似文献
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Modelling site quality and individual-tree growth in pure and mixed Pinus brutia stands in north-east Greece 总被引:1,自引:0,他引:1
Marc Palahí Timo Pukkala Dimitrios Kasimiadis Konstantinos Poirazidis Aristotelis C. Papageorgiou 《Annals of Forest Science》2008,65(5):501-501
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We studied the relationships among 5-year radial (diameter and basal area) growth of red oak (genus Quercus, subgenus Erythrobalanus) crop trees and predictor variables representing individual tree vigor, distance-dependant competition measures, and distance-independent competition measures. The red oaks we examined are representative of the commercially and ecologically important oak species of the bottomland hardwood forests of the southeastern US. The crown class score, a quantitative measure of crown class and tree vigor, performed best in accounting for the variability in tree diameter growth. Plot-level variables failed to account for a significant proportion of the variability in tree radial growth. The basal area of the first-order neighbors that were taller than the crop trees and located within 2.4 times the mean overstory crown radius had the highest negative correlation with crop tree 5-year radial growth. Red oaks were a major part of these competitors and likely exerted the greatest competitive pressure. However, crop tree radial growth was positively associated with the basal area of the red oaks which were indirect (second order) neighbors and which were taller than the crop trees. It is possible that indirect neighbors do not compete with the crop trees, but they likely compete with the direct competitors of the crop trees, thus having an indirect positive influence on crop tree growth. Such reasoning is consistent with previously observed spatial dependence up to four times the mean overstory crown radius. The findings may have implications for thinning hardwoods stands and crop tree management in that foresters need to take into account (1) oak intra-genus competition, (2) the negative competitive effect of direct neighbors, and (3) the potentially positive effect of the indirect neighbors, the competitors’ competitors. 相似文献
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Changes in soil faunal assemblages during conversion from pure to mixed forest stands 总被引:1,自引:0,他引:1
Matthieu ChauvatDagmar Titsch Andrey S. ZaytsevVolkmar Wolters 《Forest Ecology and Management》2011,262(3):317-324
Replacement of native deciduous forests by coniferous stands was a common consequence of former European afforestation policies. However, these changes have proven to lead to serious ecological problems. Therefore, re-establishing mixed forests with native tree species became an increasingly popular management strategy to fulfil the demands of multi-functional forestry. We report about changes in collembolan assemblages and microbial performances during conversion of pure coniferous stands to mixed forests. The study was carried out in the Black forest area (SW of Germany), where a gradient of conversion from pure spruce stands (S1) to equally mixed stands (spruce, beech, and fir) at S4, through two intermediate stages (S2 and S3) was selected. Results clearly indicated strong modifications of the collembolan communities with an enrichment of the assemblages over the course of the conversion process. Mean species richness increased by 47% from S1 to S4 accompanied by diversity indices (Shannon and Simpson) higher at S4. Significantly different soil biota assemblages were found at each phase of the conversion process. Spatial turnover and nestedness contribute almost equally to the modification of assemblages from S1 to S2 while later on in the mixing process only spatial turnover was acting. Concomitantly, significant shifts in the functional structure of the collembolan assemblages were depicted, deep-dwelling collembolan (euedaphic) being, surprisingly, the most responsive group. In contrast, neither microbial nor coarse environmental parameters were influenced by the factor “conversion phase”. We suggest that stimulation of Collembolan communities after the mixing process was mainly due to the input of more suitable food sources and/or microhabitat increases. Our findings underline the crucial role of aboveground processes on the belowground system, with the intensity and scheme of the mixing-process as important factors to consider when aiming at soil biodiversity improvement in forest systems. 相似文献
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于湖南省杜家冲林场湿地松枫香混交林内设置4块具有代表性的样地进行调查,利用混交度、大小比数、角尺度3种结构参数,分析其林分空间结构特征。结果表明:该林分的平均混交度为0.678,属于中度偏强混交,说明该森林群落较为复杂与稳定;林分平均角尺度为0.475,林木空间分布格局为均匀到随机分布;样地平均胸径大小比数的取值范围在0.27~0.87之间,且湿地松(0.27)枫香(0.47)香樟(0.59)木荷(0.87),说明各树种在样地中分化较严重,湿地松和枫香在样地中较占优势。 相似文献
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Mathieu Jonard Frédéric André François Jonard Nicolas Mouton Pierre Procès Quentin Ponette 《Annals of Forest Science》2007,64(2):141-150
Total Soil Respiration (TSR) was measured in pure and mixed stands of oak and beech and was partitioned into two contributions using the forest floor removal technique: Mineral Soil Respiration (MSR) and Forest Floor Respiration (FFR). In addition, laboratory incubations of the forest floor and the Ah horizon were performed to evaluate the heterotrophic respiration and the DOC production of these horizons. The relationships between soil temperature and the various soil respiration contributions in the three stands were compared using Q 10 functions. In situ, significant differences (α = 0,05) between stands were observed for the R 10 parameter (respiration rate at 10 °C) of the TSR, MSR and FFR contributions, while only the temperature sensitivity (Q 10) of TSR was significantly affected by stand composition. The effect of soil water content was only significant on MSR and followed different patterns according to stand composition. Under controlled conditions, the R 10 of the forest floor and of the Ah horizon varied with stand composition and the Q 10 of the forest floor decreased in the order: oak (2.27) > mixture (2.01) > beech (1.71). 相似文献
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闽南山地马尾松火力楠混交林的生物量和土壤肥力研究 总被引:4,自引:0,他引:4
基于对闽南山地马尾松火力楠混交林及马尾松纯林的大量调查,分析了经营混交林与纯林对生物量及土壤肥力所产生的影响。结果表明:与马尾松纯林相比,马尾松火力楠混交林对生物量积累具有显著的促进作用,对林地土壤具有明显的改良作用,土壤水分、养分状况明显改善。建议今后应尽量避免连茬经营人工纯林,提倡营造针阔混交林。 相似文献