Effects of nitrogen sources and glucose on the consumption of ethylene and methane by temperate volcanic forest surface soils

There is limited knowledge with regard to the consumption of ethylene (C2H4) and methane (CH4) in volcanic forest soils containing low microbial carbon-to-organic carbon ratio, and to the responses of both consumptions to nitrogen and carbon additions. Temperate volcanic forest surface soils under three forest stands (e.g. Pinus sylvestris L., Cryptomeria japonica and Quercus serrata) were used to compare CH4 and C2H4 consumption by forest soils, and to study the effects of nitrogen sources and glucose on both consumptions. There was a good parallel between CH4 and C2H4 consumption by for- est soils, but mineralization reduced CH4 consumption rather than C2H4 consumption in forest soils, particularly in a Pinus forest soil. The stimulatory effect of glucose addition on both CH4 and C2H4 consumption by forest soils was increased by increasing the pre-incubation period after glucose addi- tion, and a largest stimulation occurred in the Pinus forest soil. The addition of KNO3-N at the rate of 100 μg·g1 significantly reduced the consumptions of both C2H4 and CH4 by forest soils (P≤0.05). In the presence of urea plus dicyandiamide, the consumption rates of C2H4 and CH4 by forest soils were higher than those in the KNO3-N and urea-N treated soils at the same N rate (P≤0.05), but were similar to those of the control. Hence, under experimental conditions, there was a strong inhibitory effect of NO3 rather than NH4 addition on the CH4 and C2H4 consumption in these forest soils. When amount of the added NO3-N increased up to more than 2―3 times the soil initial NO3-N concentrations, both C2H4 and CH4 consumption rates were reduced to 10%―20% of the rates in soils without nitrate addition. By comparing the three forest stands, it was shown that there was a smallest effective concentration of the added nitrate that could inhibit C2H4 and CH4 consumption in the Pinus forest soil, which indicated that C2H4 and CH4 consumption of the soil was more sensitive to NO3-N addition.     

法律视野中的湿地和湿地自然保护区

湿地是与森林、海洋并称的地球三大生态系统之一。我国湿地资源丰富，但目前湿地面临着面积锐减和功能退化的威胁。法律视野中的湿地和湿地自然保护区存在着立法进程不快、执法管理不力、公众参与不够的问题。由此提出的对策建议是：积极稳妥地推进《湿地法》的立法、出台专门的《湿地自然区保护条例》、按“一区一办法”的思路制定地方法规、加大现行法律法规执法的力度、不断扩大公众的参与。     

组织合作机制的生态系统管理——一个简单分析框架

现代组织需要可持续笈展和科学的发展观的引导,合作机制在一定程度影响着组织乃至整个社会的均衡发展。首次将生态系统管理理念引入具有仿生性和特异性的组织合作机制中,从混沌理论角度挖掘其内在平衡机制,探讨了该体系中的生态失衡问题,如制度失衡、空间失衡等,最后基于生态角度提出优化生态位、柔性化合作边界等政策建议。     

四川省实施退耕还林（草）工程的生态学建议

退耕还林（草）工程的实施，必须严格遵循生态原理。本文针对四川省生态环境特征，对四川实施退耕还林（草）工程提出了一些生态学方面的建议。     

GIS软件景观生态学指数的二次开发

利用GIS软件ARC／INFO的扩展语言（AML）对景观生态学指数进行了计算，并设计了一个简单的菜单显示系统。此系统集图、文于一体，不仅能计算一般常用的景观生态学指数，而且能方便地显示和查询景观信息。     

四川丘陵地区鸟类现状及分析

对四川省丘陵地区的鸟类资源进行了初步调查，报道鸟类共有110种，分属13目32科，其中国家Ⅱ级保护鸟类有5种，四川省重点保护鸟类有6种，分析其生境状况，阔叶林是鸟类的最适生境。     

森林覆盖率与水土流失及荒漠化的数学模型

通过我国森林覆盖率与水土流失及荒漠化这三个变量之间的依存关系 ,找出它们之间的规律性 ,以此提出相应的数学模型 .     

黔中地区岩溶洞穴翼手类的初步调查及部分生态观察

从 1995年 5月至 1999年 12月间对黔中地区的龙天洞、唐官大坡洞、和尚洞和大洞口等 2 1个洞穴的翼手类进行了初步调查 ,共捕获标本 2 0 0余号 ,经鉴定计 16种 ,隶属 3科 7属。此外 ,还对翼手类的部分生态进行了观察 ,共观察多种翼手类 10 0 0余只。分析了光和温度对翼手类活动的影响及湿度对翼手类分布的影响 ,翼手类的水平和空间分布、昼夜活动及在洞穴生态系统中的作用。还对翼手类的保护进行了探讨     

山西省农林系统科研院所科研状况调查分析

文章通过对山西省农林系统科研院所现状调查分析，提出了其今后发展的出路及对策。     

周至自然保护区的竹林及大熊猫分布研究

秦岭北麓惟一的大熊猫分布区———周至保护区的大熊猫少为人知 ,论述了保护区内竹子的种类、生境、分布及大熊猫的数量、生境和分布 .