台风“山竹”对粤港澳大湾区城市园林树木的影响调查

2018年9月,台风山竹对粤港澳大湾区城市的园林树木造成重大伤害,调研粤港澳大湾区6个城市的园林树木的受损情况,统计各树种的综合受损率及受损表现,应用聚类分析法,对受损树种进行分级,并确定树种整体受损等级。通过记录树木受损情况及分析树种自身的抗风特性,分析总结影响园林树木抗风性能的主要因素,包括树种本身的抗风特性、台风风力与风向、立地土壤环境、种植穴空间、植物群落密度、迎风口种植位置等,并提出建立完善的树木风险评估体系,加强园林绿化建设及养护管理,以增强城市园林树木抗风能力。     

中国天山山区药用植物资源及其保护与利用

天山山区得天独厚的自然条件孕育了丰富的药用植物资源，加上多民族聚居，三大医药体系交融等人文条件，使这些药用植物长期以来在当地居民与疾病作斗争中发挥了重要作用，据估算，整个天山山区有药用植物200多种，依功能，疗效可分为16类，在对这些资源的开发，利用与保护上，仍存在众多的问题，本文对存在的问题予以分析并提出了相应的对策；指导思想上，阐述了利用与保护的关系；利用方面，提出了加速升值研究；保护方面，提出了变消极保护为积极保护。     

新疆山地针叶林植物物种组成与丰富度研究

通过对新疆阿尔泰山、天山北坡、天山南坡和昆仑山西部11个地点122个样方的调查,发现阿尔泰山针叶林植物(包括乔木、灌木和草本)丰富度显著高于天山南坡和昆仑山;天山南坡和昆仑山物种组成相似,阿尔泰山和天山北坡物种组成相似.全疆针叶林物种丰富度随年平均气温和海拔的增加显著下降,随纬度的升高显著升高.在不同区域,物种丰富度随...     

中国天山山区新疆贝母居群遗传多样性及其环境适应性

新疆贝母(Fritillaria walujewii)具较高的药学利用价值,但现存量稀少,被列为新疆Ⅰ级保护植物。通过选取3个叶绿体基因片段,分析新疆贝母18个居群的遗传多样性,检测18个居群样地的土壤因子,利用SPSS软件分析了遗传多样性与土壤因子的关系。结果表明:新疆贝母居群总的遗传多样性较高,单倍型多样性指数与土壤中的全盐、SO_4~(2-)、Ca~(2+)、Mg~(2+)、有机碳、有机质、全氮、全磷含量呈显著正相关;平均等位差异与土壤SO_4~(2-)、Ca~(2+)、有机碳含量呈显著正相关;核苷酸多样性指数与土壤中的全盐、SO_4~(2-)、Ca~(2+)、Mg~(2+)、有机碳、有机质、全N呈极显著正相关,与土壤pH呈显著负相关。对新疆贝母居群土壤因子进行主成分分析,得到3个主分量,占总信息量的80.22%,得出新疆贝母的分布主要与全盐、有机碳、有机质、全N、全P、Ca~(2+)、SO_4~(2-)有关。土壤中硫酸盐和土壤有机质与新疆贝母居群遗传多样性显著相关,对新疆贝母居群的遗传多样性具有一定程度的选择性压力,在维持新疆贝母居群遗传多样性方面扮演较重要的角色,同时在一定程度上影响了新疆贝母目前的分布格局。     

On sustaining the ecology and livestock industry of the Bayanbuluk Grasslands

A short visit to the Bayanbuluk Grassland in the Tianshan Mountains, Xinjiang, PRC, revealed a number of environmental and livestock production problems, including grassland degradation, loss of grassland biodiversity, soil erosion and flash flooding downstream, decreased pasture productivity, and poor livestock nutrition (especially in winter) leading to stock losses and flocks and herds of low productivity. This paper describes those problems and then suggests some solutions. Short duration, high intensity grazing could be one of the solutions to both improving grassland condition and improving livestock nutrition. Local production of fodder crops for feeding in winter and spring deserves testing, using adapted strains of Alfalfa (Medicago sativa) and trialling fodder root crop production. It is important to realise that the land management objectives of scientists, administrators, herders and farmers may be similar, and that there are opportunities for land improvement through working together.     

我国高原土壤资源的特点及合理利用

本文根据１９８７－１９９０年对昆仑山区的实地考察资料，阐述了我国高原土壤形成环境及高原土壤资源的特点，进而提出了合理利用建议。并侧重列示了在这次考察中首次发现的石膏寒漠土、龟裂土及碱土的主要理化性质。     

甘肃兴隆山白粉菌种群生态分布及生态位调查

对甘肃兴隆山白粉菌种群进行了生态分布调查和生态位分析,结果表明:白粉菌在该区普遍发生,其多样性与植被种类的多样性直接相关,环境湿度对病害严重度有较大影响,在高海拔低温低湿地段白粉菌分布较少,危害较轻;而在低海拔湿度相对较高的地段白粉菌种类多,危害严重,发病寄主多呈均匀分布或团块状分布。Sphaerotheca和Erysiphe的生态位宽度最大,其B值分别为BSph.=1.000,BE.=0.974,说明这2个属的白粉菌比别的属种对环境的适应性要强,对资源的利用宽度更大。     

长白山林区运材公路路面设计交通量计算中的α系数的探讨

1982年,在本刊曾对大、小兴安岭林区运材公路路面设计的交通量计算中的α系数进行了探讨,对公式n=(Qα)/(qT)中的α系数给予确切的定义,称α为季节性交通量综合不均衡系数,并建议α=0.8—0.9。本文为进一步地探讨,对公式n=(Qα)/(qT)的形式作了追溯,并根据我国现行柔性路面设计方法和林区公路运材特点进行分析,进一步指出林区公路路面设计应以不利季节(北方为春融期)为依据,α的内涵应为季节性交通量不均衡和不利季节车辆装载不均衡,即α=α1·α2。通过长白山林区四个林业局五条干线的调查分析,该地区α=0.9。验证以往α取值为1.2和现采用α=0.9,分别计算交通量和路面结构设计,结果α=0.9的路面基层厚度减薄4cm,且其厚度值在《规程》规定经验值范围内,并更接近于实际厚度。说明α=0.9技术可靠,经济合理。这对完善我国林区公路路面设计方法的有关参数,将有现实意义。     

针叶林标准化地位指数在大兴安岭林区立地质量评价中的应用(英文)

本文采用两点法原理和方法，对大兴安岭地区的落叶松和樟子松人工林地位指数表进行分析，建立了大兴安岭人工针叶林标准化生长模型，按模型导出各生长指数级和各龄阶理论值，并建立了标准化地位指数表。理论值检验结果表明，该标准化地位指数表符合精度要求。本项研究解决了大兴安岭地区针叶林同一立地类型不同树种地位指数和不同树种不同立地类型地位指数间的相互转换。     

Soil-geomorphic significance of land surface characteristics in an arid mountain range,Mojave Desert,USA

Mountains comprise an extensive and visually prominent portion of the landscape in the Mojave Desert, California. Landform surface properties influence the role these mountains have in geomorphic processes such as dust flux and surface hydrology across the region. The primary goal of this study was to describe and quantify land surface properties of arid-mountain landforms as a step toward unraveling the role these properties have in soil-geomorphic processes. As part of a larger soil-geomorphic study, four major landform types were identified within the southern Fry Mountains in the southwestern Mojave Desert on the basis of topography and landscape position: mountaintop, mountainflank, mountainflat (intra-range low-relief surface), and mountainbase. A suite of rock, vegetation, and morphometric land surface characteristic variables was measured at each of 65 locations across the study area, which included an associated piedmont and playa. Our findings show that despite the variation within types, landforms have distinct land surface properties that likely control soil-geomorphic processes. We hypothesize that surface expression influences a feedback process at this site where water transports sediment to low lying areas on the landscape and wind carries dust and soluble salts to the mountains where they are washed between rocks, incorporated into the soil, and retained as relatively long-term storage. Recent land-based video and satellite photographs of the dust cloud emanating from the Sierra Cucapá Mountains in response to the 7.2-magnitude earthquake near Mexicali, Mexico, support the hypothesis that these landforms are massive repositories of dust.