不同林型土壤有机碳及腐殖质组成的分布特征

为探讨不同类型人工固沙林下土壤有机碳的差异,以辽宁省章古台沙地5种林型下土壤为研究对象,运用统计学的方法对0—5,5—10,10—20,20—40cm土层有机碳、全氮、腐殖质组分分布特征进行比较分析。结果表明:在各林型0—40cm土层上,土壤有机碳含量变化特征为樟子松纯林(4.72g/kg)怀槐樟子松(4.48g/kg)榆树樟子松(4.38g/kg)云杉樟子松(4.21g/kg)杨树纯林(3.95g/kg)对照(1.88g/kg);有机碳储量表现为怀槐樟子松(20.00t/hm~2)樟子松纯林(19.92t/hm~2)榆树樟子松(19.06t/hm~2)云杉樟子松(17.31t/hm~2)杨树纯林(16.61t/hm~2)对照(8.44t/hm~2);经腐殖质组分分析发现土壤腐殖质碳含量表现为云杉樟子松(2.04g/kg)榆树樟子松(1.93g/kg)樟子松纯林(1.74g/kg)杨树纯林(1.65g/kg)怀槐樟子松(1.58g/kg)对照(0.75g/kg)。各林型土壤有机碳含量与全氮、腐殖质碳、胡敏酸、富里酸均呈极显著的正相关关系。     

森林可持续发展的动态优化模型

运用动态规划方法讨论森林可持续发展问题，建立了森林自然发展模型和森林可持续发展的优化开发模型，给出了相应的迭代公式，并选用青冈－夏蜡梅群落进行模拟计算。结果表明经过一段时间的自然发展，森林群落可达到稳定态，夏蜡梅群落必将过渡到青冈－夏蜡梅稳定群落。其后，各阶段各树种的数量有微小变化，但总体稳定，且算法快速收敛于稳定点。图3表2参4。     

浙江省平原农田林网化的研究

根据浙江省平原地区的特点,依照农作物对农田林网控制的要求,提出了平原农田林网化的规划设计原则、要求和浙江省的分区规划方案。     

安顺市环城林带绿化设计方案初步分析

阐述了安顺市环城林带绿化建设工程的绿化设计方案,对设计方案中的立地类型划分、树种选择、造林类型及混交设计、造林密度和配置方式等进行了初步分析,并对后期管理提出建议。     

Sprouting characteristics of a subtropical evergreen broad-leaved forest following clear-cutting in Okinawa,Japan

This study explores the sprouting characteristics of an evergreen broad-leaved forest after clear-cutting based on a survey of 1,893 stumps of 62 tree species in Okinawa, Japan. The sprouting capabilities of the stumps varied among tree species. The stumps of 60 species could produce sprouts, while those of the other two species could not. In 10 of the sprouting species, the mean sprout-stem number was higher than 4.0 stems per stump; nine sprouting species showed low sprouting capabilities. Additionally, Castanopsis sieboldii and Schima wallichii, the dominant species, exhibited high sprouting capabilities. Further, the sprouting capabilities varied with stump diameter at breast height (DBH). Stumps with a larger DBH tended to have a higher mean number of sprout stems per stump, higher DBH, and higher tree height than the smaller stumps. The forest stands regenerated by sprouting might recover into a tree community similar to that before clear-cutting.     

不同采伐强度对闽西常绿阔叶林林分结构稳定性的影响

应用多样性分析方法和改进后的 M.Godron 稳定性测定方法研究常绿阔叶林5种不同强度采伐(弱度9.8%、中度24.5%,强度46.8%和极强度72.3%和皆伐)作业10 a后林分结构稳定性.结果表明,择伐林地林分处于稳定状态,随着择伐强度的增强,林分的稳定性开始逐渐降低.皆伐林地林分处于不稳定状态.对于常绿阔叶林的科学经营,从稳定性出发,应尽量采取择伐方式,尤其是中低强度的择伐方式.     

江西公益林资源数据库建设面临的问题及对策

分析了江西省首批纳入中央财政补助公益林基础图表数据存在的问题,并提出了相应的对策建议。     

Human Impacts on Forest Biodiversity in Protected Walnut-Fruit Forests in Kyrgyzstan

We used a spatially explicit model of forest dynamics, supported by empirical field data and socioeconomic data, to examine the impacts of human disturbances on a protected forest landscape in Kyrgyzstan. Local use of 27 fruit and nut species was recorded and modeled. Results indicated that in the presence of fuelwood cutting with or without grazing, species of high socioeconomic importance such as Juglans regia, Malus spp., and Armeniaca vulgaris were largely eliminated from the landscape after 50–150 yr. In the absence of disturbance or in the presence of grazing only, decline of these species occurred at a much lower rate, owing to competitive interactions between tree species. This suggests that the current intensity of fuelwood harvesting is not sustainable. Conversely, current grazing intensities were found to have relatively little impact on forest structure and composition, and could potentially play a positive role in supporting regeneration of tree species. These results indicate that both positive and negative impacts on biodiversity can arise from human populations living within a protected area. Potentially, these could be reconciled through the development of participatory approaches to conservation management within this reserve, to ensure the maintenance of its high conservation value while meeting human needs.     

萍乡采矿废弃区退化森林的恢复与重建技术

借鉴国内外采矿废弃区退化森林的恢复重建经验,阐述了萍乡采矿废弃区退化森林的恢复、重建技术,并总结提出了萍乡采矿废弃区退化森林的恢复、重建的措施。     

仙游县天然林停伐管护问题分析及对策建议

指出了停止天然林商业性采伐是党中央、国务院为保障森林资源安全,增强森林生态功能而做出的一项重大决策,对于推进生态文明建设有重大的意义。通过实地调查,认真分析了仙游县天然林停伐管护补助工作中存在的问题,并提出了切实可行的实施建议。以供参考。