辐射松根朽病与林龄和环境条件关系的数量化分析

对新西兰辐射松根朽病（Ａｒｍｉｌｌａｒｉａｓｐｐ．）的发病程度与林令和环境条件的关系进行了数量化分析。结果表明影响该病发生的主要因素有：年降雨量、地形、土壤类型、前作以及它们之间的互作关系。以此建立的多无线性回归模型为：＝－４．３＋５．４Ｒ２＋１２．４ｓ４＋７．８ｐ１＋６．７ｐ２＋２９Ｌ２＋３１．１Ｒ２ｐ１Ｌ２．根据这一模型可预测新西兰境内任一给定的条件下根朽病的可能侵染水平,以供造林设计和防治时参考。     

食用菌工厂化生产模式探讨

食用菌工厂化生产是食用菌产业发展的重要趋势,是食用菌生产技术进步的结晶.国外少数国家实现了部分食用菌的工厂化和自动化生产,我国的食用菌产业仍处于农户栽培模式的初级阶段,工厂化规模生产亟待加强.详细介绍了食用菌工厂化生产的特点、国内外食用菌工厂化生产的现状、存在问题、解决措施及我国食用菌工厂化的发展前景.     

“丝绸之路”(中国段)遗址环境监测规划

基于目前"丝绸之路"遗址环境监测中存在的管理体制混乱、缺乏健全的法律保障、监测对象简单化和遗址环境监测范围较小等问题,从主观和客观方面分析了原因。并对目前"丝绸之路"遗址中存在的大气污染、水环境污染等问题进行了分析和预测。最后,制定了相关的防治和监测规划,为促进"丝绸之路"旅游业和文物古迹保护的和谐及可持续发展奠定基础。     

Wind dispersal of oribatid mites as a mode of migration

Oribatid mites are important colonizers of young soils, but little is known about their immigration pathways. In this study, one often-stated hypothesis was tested quantitatively: that wind is an important dispersal pathway. The aim was (1) to detect wind dispersal in oribatid mites (using sticky traps at different heights above ground level) and to determine factors influencing wind dispersal, (2) to investigate whether oribatids can survive wind dispersal and immigrate by wind into young soils (using mini-pitfall traps in test plots with oribatid-free substrate, active immigration being prohibited) and (3) to find out whether those oribatids are able to colonize young soils (using soil cores from the test plots). The results demonstrate (1) that mainly arboreal oribatid species were dispersed by wind - even at 160 m height - and can therefore be spread over large distances. Nevertheless, about 10% of the wind-dispersed oribatid mites belonged to species able to live in the soil and may therefore be potential colonizers of young soils. The number of specimen and species transported by wind was the highest close to the soil surface and the number of dispersed individuals was mainly influenced by seasonality and humidity. The results also suggest that the probability of a soil oribatid being dispersed by wind depends on its original microhabitat (tree habitats > soil surface > deeper soil layers) and its body weight. It was also shown that soil-dwelling oribatid mites survived wind dispersal and immigrated by wind into the test plots and that colonization of the test plots took at least 2 months longer than immigration. However, colonization success was low during the first 2 years of investigation and only Trichoribates incisellus was found several times in the nutrient-poor substrate. Therefore, wind dispersal is an important migration pathway, especially for arboreal oribatids. We suggest that immigration into young soils most likely occurs by repeated short-distance dispersal. Only some species are able to survive the hostile conditions of wind dispersal as well as of pioneer soils, but those that do are potentially the founders of new populations.     

Mobility and phytoavailability of arsenic in an abandoned mining area

The mobility and phytoavailability of arsenic in an area affected by the abandoned exploitation of an arsenical tungsten-tin deposit was studied to establish the current and eventual environmental risks and to propose possible remediation practices. Soil and plant samples were collected at different distances from the polluting sources and analyzed for their As content and distribution. Critical soil total concentrations of As were found, with values in the range 175-2300 mg kg^− 1. The readily labile As contents represent < 0.2% of the total concentrations, whereas the As contents more prone to be mobilized could rise up to 25%. Different phytostabilizing plants were identified, namely, Agrostis castellana (Boiss. & Reut.), Centaurea jacea L., Eryngium campestre L. and Scirpus holoschoenus L.. Such plants show important root bioaccumulation factor values in relation to the labile As contents (up to 197, 58, 201 and 88, respectively) and low translocation factor values (down to 0.170, 0.032, 0.173 and 0.036, respectively). Additionally to promote the revegetation with these plants, the species Rumex acetosella L. should be eliminated as this behaves as an index plant, reaching above-ground As concentrations up to 218 mg kg^− 1.     

环保型长效化肥聚脲甲醛的合成研究

合成了环保型长效聚脲甲醛化肥 ,并对其合成的全过程进行了研究 ,结果表明反应温度为50℃～ 6 0℃ ,反应的第一阶段 pH值为 8,反应的第二阶段 pH值小于 4时 ,能获得较高产率的制品 ,最后对产物进行了表征     

黄淮海平原旱田氮素损失特征及其环境影响研究

利用N素平衡参数和统计数据计算黄淮海平原地区主要农作系统冬小麦田和夏玉米田N素损失特征及其环境影响研究结果表明,1992~1998年随N肥用量的增加,每公顷农田N肥总损失量及氨挥发、硝化-反硝化、淋洗与径流等损失量呈逐年递增趋势,且不同N肥利用率、土壤残留率和损失率不同,同一N肥在不同农作系统中利用率、土壤残留率及损失率亦不同,夏玉米田N肥损失率高于冬小麦田。并探讨了N肥损失的环境影响及主要技术对策。     

环境因素对大棚温室无土草坪生产的影响研究

以冷季型划种高羊茅（Festuca elata Keng）为材料,研究光、湿度、基质肥水条件以及植物生长素对大棚湿度草坪生产的影响结果表明,温度宜控制在15－25℃,且昼夜应保持一定温差;湿度宜在40％－60％间,为促进根系生长应控制在50％－60％间;光照应保持在1.5万lx以上;适当施肥补充养分和运用植物生长素可作为环境微调措施,有利于提高草坪质量和快速成卷。     

河间地区的地热资源特征及其开发利用中的问题

“七五”期间,河北省河间县作为农村能源综合建设试点县之一,其地热资源丰富,是农村能源的重要组成部分。本文通过对河间地区的地质构造、地温分布、热储特征的调查,对地热水量、温度、压力、化学成分和同位素组分的监测和测定,对该地区的地热资源进行了评价,并研究了地热水利用对环境的影响。     

我国生态农业与生态环境保护协协性研究

在提高农业生产力的同时，保护生态环境质量是我国生态农业的基本特点，本文分析了我国生态农业产生的背景、发展现状、功能及特色，并以黑龙江省拜泉县为例，阐明生态农业建设与生态环境保护的协调性关系。