The landscape ecology of large disturbances in the design and management of nature reserves

Large disturbances such as fires and floods are landscape processes that may alter the structure of landscapes in nature reserves. Landscape structure may in turn influence the viability of species and the functioning of ecosystems. Past reserve design and management strategies have been focussed on species and ecosystems rather than on landscape-scale processes, such as disturbance.An essential feature of a natural disturbance regime is the variation in disturbance attributes (e.g., size, timing, intensity, spatial location). Although some past reserve management policies have included natural disturbances, perpetuating disturbance variation has not been the explicit goal of either reserve design or management.To design a reserve to perpetuate the natural disturbance process requires consideration of: (1) the size of the reserve in relation to maximum expected disturbance size, (2) the location of the reserve in relation to favored disturbance initiation and export zones and in relation to spatial variation in the disturbance regime, and (3) the feasibility of disturbance control at reserve boundaries, or in reserve buffers.Disturbance management possibilities are constrained by the design of the reserve and the reserve goals. Where a natural disturbance regime is not feasible, then it is important that the managed disturbance regime mimic historical variation in disturbance sizes and other attributes as well as possible. Manipulating structure on the landscape scale to restore landscapes thought to have been altered by historical disturbance control is premature given our understanding of spatial disturbance processes in landscapes.     

浅谈平原园林绿化施工

结合企业绿化施工项目的实施，从准备工作、土方施工、种植和养护管理4个方面对平原绿化施工进行了论述。     

湖南省森林公益效能的经济评价Ⅰ森林的木材生产效益与水源涵养效益

根据多年定位测定的数据以及<湖南省森林资源主要数据汇编>、<湖南省农业区划(8)>和湖南省水利厅有关资料,对湖南省森林的木材生产效益和水源涵养效益进行计量评估,结果表明,湖南省现有的森林每年生长木材488.7675万m3,年平均生产木材效益24.44亿圆,而其森林的水源涵养效益中,森林贮水功能效益9.84亿圆,防洪效益3.68亿圆,枯水期增加的水资源利用效益26.73亿圆.其涵养水源总效益共计40.25亿圆,是木材效益的1.65倍,同时,即使是灌草坡地调节水分的能力也明显高于裸地,因此.从水文学观点出发,对于难以造林的山坡、山顶,要注意灌木林的保护和经营,使其发挥更好的防水功能.     

Pattern of Kirtland's warbler occurrence in relation to the landscape structure of its summer habitat in northern Lower Michigan

Studies of the endangered Kirtland's warbler in relation to landscape ecosystems were conducted from 1986–1988 on a large wildfire-burn surrounding Mack Lake in southeastern Oscoda County, Michigan. A landscape ecosystem approach was used to distinguish low- and high-elevation segments of the landscape, as well as 11 local ecosystem types. The ecosystems were distinguished by physiography, microclimate, soil, and vegetation. The early occurrence of the warblers was strongly related to landscape structure, i.e., to the broad low- and high-elevation areas and the local ecosystem types within them. Territories of male warblers were observed in 5 of the 11 ecosystems. The five ecosystem types where warblers were observed were characterized by (1) a physiography of level or rolling terrain; (2) soil series of Grayling, Graycalm, Montcalm, or Rubicon; (3) uplands with relatively warm temperature during the breeding season; (4) vegetation dominated by low sweet blueberry, bearberry, wintergreen, northern pin oak, blue stem grasses, and hair cap moss; and (5) canopy of relatively tall, dense, and patchy jack pine and oak. Landscape structure appears to be an important factor affecting the occurrence of the warbler in its summer habitat in northern Lower Michigan.     

乳牛体型性状线性评定数学模型的指导和应用

本文说明了乳牛体型性状线性评定的常规方法,在此基础上推导出了该评定方法的数学模型。该模型的提出,极大地简化了常规评定方法的繁琐计算,值得在乳牛业生产实践中推广使用。     

浅谈园林植物配置的艺术手法

随着城市的发展，园林植物在景观上的作用越来越重要，文章主要分析园林植物外在的线条、外形、质地、色彩的特性，并归纳了一些处理植物配置与色彩、质地、距离、光影、地形等之间关系的艺术手法。     

福建省农业科技期刊学术影响力的评估与分析

对福建省16种农业科技期刊连续10年的总被引频次和他引率进行统计与比较。结果表明，《福建农林大学学报（自然科学版）》、《福建林学院学报》、《福建农业学报》3种学术类期刊和《福建农业科技》、《福建林业科技》2种技术类期刊且有较高的学术影响力。并对统计结果和统计方式进行了分析。     

川西地区森林游憩资源分布及其特色初探

在详细调查川西森林游憩资源的基础上,分析了该地区森林游憩资源的特色。     

应用国标评价和计算毛竹林的经济效果

应用国家标准GB3533．1-83《标准化经济效果的评价原则和计算方法》和GB3533．3-84《评价和计算标准化经济效果数据资料收集和处理方法》中的基本原理和方法，可以准确而全面地评价毛竹林培育的经济效果。文章根据福建省毛竹生产实际，论述了标准化经济效果评价和计算方法如何在评价和计算毛竹林培育经济效果中的应用。     

利用模糊数学综合评价天然气管道的内腐蚀

通过对管道内腐蚀程度进行定量评价,了解管道的内腐蚀情况,是管道剩余强度评价、剩余寿命预测以及可靠性分析的基础.提出了利用模糊数学综合评价方法对天然气管道内腐蚀程度进行综合评价的具体方法,并通过应用实例验证了该评价方法的可行性.