大岗山林区水体、空气、噪声环境背景值研究*

研究表明大岗山林区水体的微量元素环境背景值均不超过世界天然水的环境背景值，水理化性质及微量元素含量均达国内外规定的生活饮用水水质标准；ＳＯ２、ＮＯｘ、总悬浮颗粒物含量均达到《中国大气环境质量标准》一级标准；噪声也不超过国际国内标准，整个林区环境质量优良，生物与环境的生态关系协调并相互适应。     

非洲菊切花保鲜剂的研究

本文研究由蔗糖、硝酸银、8-HQ(8-羟基喹啉)配制的不同保鲜剂对非洲菊切花插瓶寿命、水分平衡、鲜重变化及观赏值等指标的影响。结果表明：4％蔗糖 200mg／L硝酸银 200mg／L硫酸铝 320mg／L8-HQ的保鲜效果最好。     

旱坡地集水枣园土壤水分动态研究

在旱坡地上采取隔坡集蓄径流水平沟的整地方法营建枣园，集蓄坡面径流，增加枣园土壤含水率，有效地控制水土流失；通过对枣园土壤水分连续３年的定点观测，掌握了枣园土壤水分动态的变化规律，分析结果表明，所采取的集水工程集水效果较好。     

Using Static and Dynamic Indicators to Evaluate Soil Physical Quality in a Sicilian Area

Both capacitive indicators derived from the water retention curve and dynamic measurements of the flow‐weighted mean pore radius, R₀, were used to assess the soil physical quality of two agricultural areas (cropland and olive orchard) and two natural areas (grassland and managed woodlot plantation) potentially subject to soil degradation. The overall idea of the study was to investigate whether a dynamic indicator quantitatively derived from hydraulic conductivity measurements could be used to supplement the traditionally applied capacitive indicators retrieved from water retention measurements. According to the available criteria, only the surface layer of the cropland site showed optimal soil physical quality. In the grassland and woodlot sites, the physical quality was deteriorated also as a consequence of compaction because of grazing. Overall, the physical quality was better in tilled than nontilled soils. The optimal soil in terms of capacitive indicators had hydraulic conductivity close to saturation that was intermediate among the different land uses, and it remained 1·3–1·9 times higher than that observed in the natural sites even when the largest pores emptied. A depth effect on R₀ was observed only when larger macropores were activated. It was suggested that water transmission parameters are more affected by changes in large pore domain. The plant available water content and Dexter's S‐index showed inverse statistically significant regressions with R₀. The empirical relationships were physically convincing given that, at increasing R₀, the contribution of macropores increases, water is transmitted faster below the root zone and the soil's ability to store water is reduced. Copyright © 2013 John Wiley & Sons, Ltd.     

WATER CUTTING OF CHINESE ROSE-BETTY PRIOR

BettyPriorinrosegenus,rosebolyis-onevarietyofFlonbondaROse.ItisoneOfmodernChineserose,withcoldresistanceandagmnstpestcharactenshcsChineserosecuttase1soutOfquestionintemPeratezoneandtothe6outhoftethperat6zone,butthereexistmanyqueshonsinHarbnareawhichbelongstonortherntemperat6zonebecauseofshortergrOwingseasonandlowerairtemperatUreinautUmnandwintertmaincuttageseasonsof8ettyPnor).Theexpen-mentonwatercuthngPropagahonofBettyPnorwasconductedlnordertointroducethesspeciesintoHarbin.MThan^LSAun…     

白龙江、洮河水源涵养林区云杉落针病危险性分析评估

云杉落针病是白龙江、洮河水源涵养林区最为严重的林木叶部病害。为加强对该病的管理,有效控制其危害和在白龙江、洮河水源涵养林区乃至整个西北地区进一步扩散蔓延,参照有害生物危险性分析(Pest Risk Analysis)方法,结合该区森林资源状况和病虫害发生发展情况,对云杉落针病在白龙江、洮河水源涵养林区的潜在风险性进行了分析和评价。结果表明:云杉落针病为中度危险且接近高度危险性病害。并提出了相应的风险管理策略。     

Water transport in wood particle material

An analogy between water flux and the field of temperature gradient in a column of wood fuel chips was discovered by these experiments. The heat—mass transfer coefficient was determined by least squares method. An equation relating water flux and temperature gradient was developed and it was demonstrated that the temperature gradient was the main driving force for water transport. The mechanism was evaporation—condensation of water vapor through natural convection in air phase. The study gives a theoretical explanation for analyzing the problem of water transport in wood particle material.     

土壤-植被系统演变对生物防沙工程的影响

包兰铁路横穿腾格里沙漠的沙坡头段 ,全长近 5 0km ,这里年降水量 186mm ,流动沙丘相对高度 2 0m以上 ,以 4m·a- 1 的速度向东南方向移动。无灌溉条件下、工程措施与生物措施相结合的防沙固沙工程体系始建于195 6年 ,近半个世纪以来该体系确保了包兰铁路的畅通无阻 ,累计经济效益逾百亿人民币。虽然当初的建设者充分考虑了耐旱的乡土树种、有效的工程固沙系统 ,但很难想到几十年后的土壤 -植被系统的演变会危及整个防护体系的稳定性。植被在从人工系统向自然系统的演变中经历了覆盖度从增加到减少的自疏过程、从灌木到半灌木到草本的变化 ,其降低风速和防风的功能减弱 ;土壤从流动风沙土发育成钙积旱成土 ,地表生物结皮发育 ,增加了表土的抗风蚀的能力 ;土壤 -植被系统的演变使得降水在生态系统中的再分配过程已经彻底改变 ,并由于防护林体系配置不完善 ,在 5 0～ 5 0 0cm的土层深度一个生物成因的干旱层逐渐形成 ,新的水分平衡格局明显威胁到现有的防风固沙体系。     

喀斯特山地主要适生树种幼苗耗水量季节变化及对土壤干旱的响应

本文通过对柳杉等24个喀斯特山地主要适生树种一年生幼苗不同季节的耗水量进行比较研究、各树种幼苗在不同土壤干旱水平(A:无干旱胁迫;B:轻度胁迫;C:中度胁迫;D:重度胁迫)下的耗水量比较研究,结果表明:各树种幼苗耗水量的季节变化为:常绿树种幼苗耗水量为春季>夏季>秋季>冬季,落叶树种幼苗耗水量为夏季>春季>秋季>冬季。不同土壤干旱水平下,各树种幼苗耗水量均表现为:A>B>C>D。     

土壤含水率对I—69杨苗木生长和生物量的影响

在3种土壤含水率条件下,研究了I-69杨插条苗的苗高、叶面积等生长进程和生物量。不同供水条件下苗木的生长进程相似,低供水处理封顶期提早10～15d.生物量测定表明,I-69杨十分喜水,高供水处理(土壤含水率保持在田间持水量的96％)的生物量为低供水处理(土壤含水率为田间持水量的55％)的2.74倍。