生态设计的植物群落空间比例分配研究

研究合理的植物群落空间比例分配,不仅可为绿量计算提供科学合理的依据,而且还能为绿地系统规划设计提供参考.介绍植物群落生态设计中的关键性问题,包括群落生态关系设计、植物序列选择、垂直结构设计、栖息地设计与保护和生态功能设计.在此基础上,指出合适的空间比例分配主要由当地的气候条件及植物群落的功能来确定,但植物群落空间比例分配还随树种的生态习性、季相和平面结构等的变化而变化.最后,从当地的气候条件及植物群落的功能出发对相关研究成果进行综述,总结出景观群落适宜的乔木、灌木、地被(草坪)、绿地的比例应该在1:2 ～6:20 ～25:25 ～35,而功能群落可依据实际需求在此基础上调整某一层的比例.     

基于TM遥感图像的农村居民点分布模式研究——以济宁市微山县为例

介绍了现阶段我国农村居民点空间分布的有关内容,并针对性地根据济宁市微山县2012年TM遥感图像、地形图等得出研究区居民点空间分布特征信息,然后采用样方分析(QA)、K(d)函数以及Voronoi图分析法研究微山县居民点空间分布的特征.研究结果表明,微山县农村居民点具有明显集聚特征的空间分布,并且集聚性指数与研究尺度呈正相关关系;同时具有微观随机性、中观尺带性、宏观块状集中等特点.     

R软件在植物种群分布格局研究中的应用

【目的】研究R软件在植物种群分布格局中的应用,为分析植物种群分布格局的繁杂数据提供一种新方法。【方法】基于西双版纳20ha热带季节雨林动态监测样地的野外调查数据,以绒毛番龙眼、网脉肉托果、玉蕊树种为例,应用R软件绘制其树种空间分布图,并分析树种种群分布格局及种间关系。【结果】网脉肉托果在样地空间分布中为集群分布,而在空间分布格局中分析,在尺度0-2m为集群分布,在12～15m为随机分布;网脉肉托果和玉蕊两个树种在空间分布图中为交错分布,重叠区域不大,进行种间关系分析,两个物种在尺度0～5m无明显相关,在5～30m为负相关。【结论】R软件能够根据研究需要实现物种空间分布图的绘制、种群分布格局分析及物种相关性分析,值得推广。     

县域冬小麦生育期气候要素与产量的灰色关联度分析—以河南省为例

基于河南省及周边39个气象站1996-2015年逐日气象观测资料和冬小麦产量数据,采用灰色关联分析方法,分析生育期各气候要素与河南省县域冬小麦产量关联度的时空变化特征。结果表明:总体来看,各气候要素与河南省冬小麦产量的关联度中,气温的关联度最大,日照时数次之,降水量最小;关联度空间分布上呈现北部地区高于南部地区的格局,南北过渡性明显,尤其是南部信阳市的关联度较其它地区明显偏低。分时段来看,各气候要素与冬小麦产量关联度在1996-2010年有所下降,在2011-2015年突变上升,有明显的年际变化特征,尤其是位于西南部和南部地区的县域单元变化显著,而北部、东部和中部地区的县域单元变化较小。各气候要素与冬小麦产量关联度总体呈上升趋势,气候变化对冬小麦产量的影响逐渐显著,应积极采取策略应对气候变化的影响。     

Probability models for predicting local water quality regulations in the southern United States

Zoning restrictions and other land use regulations that may significantly impact natural resource-based industries traditionally have been the responsibility of local governments in the United States. This study uses a logistic regression model to estimate the influence of spatial and demographic factors on the probability that Georgia, Florida, and Louisiana counties adopt local regulations to improve water quality. The analysis identifies demographic and spatial factors that significantly influenced the probability a county would adopt local water quality regulations, spatially depicts which local regulations are most likely to be adopted, and maps the probability that a county would adopt the regulation.     

刺槐共生菌盆栽接种试验

在盆栽实验条件下通过生物接种技术 ,对豆科固氮树木刺槐进行联合共生体的人工构建 ,定量研究了VA菌根真菌、外生菌根真菌、根瘤菌不同组合情况下对刺槐生长的促进作用并对 3者之间的相互关系进行了探讨。研究表明外生菌根菌与内生菌根菌两者之间的混接具有增效作用 ;菌根菌与根瘤菌之间存在着协同增效作用。促进植株生长的最佳接菌组合是根瘤菌 ) 36 6 ) VAR 毛边华锈伞 (H .mesophaseum 870 191)     

退化红壤物理性质的空间异质性的初步研究

采用地统计学的理论和方法,研究退化红壤区的土壤4种物理性质的空间异质性。变异函数分析结果表明:退化红壤的物理性质有中等程度的空间相关性,土壤容重与毛管孔隙度具有明显的空间异质性,在0～20cm土层深,有效变程尺度分别为700m和12650m,自相关部分的空间异质性为68.5%和73.6%,明显大于随机部分的空间异质性;在空间自相关范围内,土壤各物理因子的空间异质性有重要的密切关系。     

Ten-year responses of ponderosa pine growth,vigor, and recruitment to restoration treatments in the Bitterroot Mountains,Montana, USA

Little is known about ponderosa pine forest ecosystem responses to restoration practices in the Northern Rocky Mountains, USA. In this study, restoration treatments aimed at approximating historical forest structure and disturbances included modified single-tree selection cutting, with and without prescribed burning. We compared the effectiveness of restoration treatments on growth, vigor, and composition of recruitment responses with untreated controls. We used a randomized block design to detect treatment differences in mean individual tree basal area increment (BAInc10), growth efficiency (GE), and recruitment abundance between two restoration treatments (Cut-only and Cut-burn) and a Control. We further examined treatment effects by tree age-class (Young, Mature, Presettlement) using a spatial ANOVA model that incorporates the spatial autocorrelation among trees within experimental units. Ten years after implementing restoration treatments, mean individual tree BAInc10 and GE were significantly higher for treated units relative to Control units; all three age-classes benefited similarly from restoration treatments relative to the Control, with the greatest response in the Cut-only and moderate response in the Cut-burn. When treated units were compared, Cut-burn negatively affected BAInc10 and GE relative to Cut-only. Presettlement trees responded positively to treatment relative to the Control, particularly for BAInc10, demonstrating the potential of these old trees to respond to reduced competition. The Cut-burn treatment, in contrast, negatively affected the BAInc10 and GE response of postsettlement trees when compared to Cut-only. Restoration treatments did not reduce the amount of Douglas-fir recruits. In addition, the recruitment of both ponderosa pine and Douglas-fir species was associated with the proximate cover of woody debris in Cut-only and Control treatments. Finally, special consideration needs to be taken for spring Cut-burn treatments, which appeared to dampen growth and vigor, relative to Cut-only, particularly for Young and Mature trees, and increased recruitment of ponderosa pine and particularly Douglas-fir.     

昆虫种群密度估计的空间自相关方法

森林害虫以往多是考虑一定面积上虫情发生量的预报,很少考虑虫情蔓延扩散情况及周围地区虫情的影响。某个林区的昆虫种群数量除自身变动外,还受周围林区种群数量变化的影响,同时各林区内种群数量变化又是时间的函数,这种复杂的相关性称为空间-时间相关关系。由于它充分考虑了林区内部及林区之间的相互影响,因此它可以用来对昆虫种群的空间-时间动态作出相关预报。我国林业害虫,由于发生面积大,如果调查的样地太少,则会遗漏某些害虫发生区,如果详细调查,则要投入大量人、物力,因此,本文提出在较少量的调查基础上,应用种群空     

南京市园林绿化树种的组成特色浅析

南京市是我国著名的园林绿化城市之一。园林绿化树种组成反映了南京地区落叶常绿阔叶混交林的地带性植被特色和乔(竹)、灌、草(地被)、藤相结合的多层次立体结构的特色。