天然次生林人工更新后对土壤物理性质及碳贮量的影响

天然林被人工林取代后对土壤水文物珲性质及土壤碳贮量有重要的影响.文章以海南天然次生林人工更新为尾细桉(Eucalyptus urophylla×E.tereticornis)和马占相思(Acacia mangium)林前后的土壤为研究对象,研究分析了人工植被更新对土壤水文物理性质和土壤碳贮量的影响.结果表明:天然次生林更新为桉树、马占相思人工林后,土壤容重增加,土壤总孔隙度、毛管孔隙度和非毛管孔隙度减小,0～80 cm土壤的最大贮水量、毛管贮水量和非毛管贮水量降低,桉树和马占相思人工林最大贮水量分别降低19.8 mm和43.3mm,桉树人工林0～40cm土壤碳贮量降低6.77t·hm-2,马占相思人工林的增加14.68t·hm-2.     

水生野生动物自然保护区环境规划指标体系的建立

从水生野生动物自然保护区的特点和实际情况出发,分析了水生野生动物自然保护区环境规划指标体系建立的原则,采用层次分析法筛选指标,建立了基于PSR框架模型的水生野生动物自然保护区环境规划指标体系.应用该指标体系对怀沙河、怀九河水生野生动物保护区进行环境功能区划,得到与实际情况较为符合的区划结果.说明该指标体系能够较为全面、准确地描述保护区的实际情况.     

自然循环式污水处理系统及应用实例研究

自然循环污水处理系统(naturalcirculationsystem,NC)是日本研究开发的一种新型的污水人工渗滤处理系统,该技术将落叶、木屑、木炭和石头等自然材料作为填料,并通过各处理单元的有效组合,使该装置内的生物净化功能达到最佳效果。在江苏省宜兴市建立的示范工程显示:NC系统对污水中几个代表性水质指标有较好的去除,CODCr、BOD5、TP和NH+4N等指标基本去除率分别为4951%~9513%、50%~80%、3560%~7813%和7198%~9844%。     

Profiling unauthorized natural resource users for better targeting of conservation interventions

Unauthorized use of natural resources is a key threat to many protected areas. Approaches to reducing this threat include law enforcement and integrated conservation and development (ICD) projects, but for such ICDs to be targeted effectively, it is important to understand who is illegally using which natural resources and why. The nature of unauthorized behavior makes it difficult to ascertain this information through direct questioning. Bwindi Impenetrable National Park, Uganda, has many ICD projects, including authorizing some local people to use certain nontimber forest resources from the park. However, despite over 25 years of ICD, unauthorized resource use continues. We used household surveys, indirect questioning (unmatched count technique), and focus group discussions to generate profiles of authorized and unauthorized resource users and to explore motivations for unauthorized activity. Overall, unauthorized resource use was most common among people from poor households who lived closest to the park boundary and farthest from roads and trading centers. Other motivations for unauthorized resource use included crop raiding by wild animals, inequity of revenue sharing, and lack of employment, factors that created resentment among the poorest communities. In some communities, benefits obtained from ICD were reported to be the greatest deterrents against unauthorized activity, although law enforcement ranked highest overall. Despite the sensitive nature of exploring unauthorized resource use, management‐relevant insights into the profiles and motivations of unauthorized resource users can be gained from a combination of survey techniques, as adopted here. To reduce unauthorized activity at Bwindi, we suggest ICD benefit the poorest people living in remote areas and near the park boundary by providing affordable alternative sources of forest products and addressing crop raiding. To prevent resentment from driving further unauthorized activity, ICDs should be managed transparently and equitably.     

Population Growth,Available Resources,and Quality of Life:China’s Post-Reform Economic Development

Two opposing intellectual traditions and their contem-porary developments regarding the relations among population, available resources, and quality of life as reflected in economic growth are reviewed. What is at issue is whether population growth is detrimental to or beneficial for economic development. Neither of the extreme views gives a complete picture of the interplay among population, resources, and quality of life. Following previous literature on the topic, this paper establishes a more balanced approach that considers the function linking population and quality of life not constant but variable and regards the limitedness of resources as not absolute but relative to regions and societies. The proposed approach is more flexible in better explaining the relation between population and economic growth. China is examined as a case in point to shed light on the interaction of population growth, economic development, and available resources, and its recent post-economic reform experiences showcase the appropriateness of the synthetic approach.     

Assessment of mammal reproduction for hunting sustainability through community‐based sampling of species in the wild

Wildlife subsistence hunting is a major source of protein for tropical rural populations and a prominent conservation issue. The intrinsic rate of natural increase. (r_max) of populations is a key reproductive parameter in the most used assessments of hunting sustainability. However, researchers face severe difficulties in obtaining reproductive data in the wild, so these assessments often rely on classic reproductive rates calculated mostly from studies of captive animals conducted 30 years ago. The result is a flaw in almost 50% of studies, which hampers management decision making. We conducted a 15‐year study in the Amazon in which we used reproductive data from the genitalia of 950 hunted female mammals. Genitalia were collected by local hunters. We examined tissue from these samples to estimate birthrates for wild populations of the 10 most hunted mammals. We compared our estimates with classic measures and considered the utility of the use of r_max in sustainability assessments. For woolly monkey (Lagothrix poeppigii) and tapir (Tapirus terrestris), wild birthrates were similar to those from captive populations, whereas birthrates for other ungulates and lowland‐paca (Cuniculus paca) were significantly lower than previous estimates. Conversely, for capuchin monkeys (Sapajus macrocephalus), agoutis (Dasyprocta sp.), and coatis (Nasua nasua), our calculated reproductive rates greatly exceeded often‐used values. Researchers could keep applying classic measures compatible with our estimates, but for other species previous estimates of r_max may not be appropriate. We suggest that data from local studies be used to set hunting quotas. Our maximum rates of population growth in the wild correlated with body weight, which suggests that our method is consistent and reliable. Integration of this method into community‐based wildlife management and the training of local hunters to record pregnancies in hunted animals could efficiently generate useful information of life histories of wild species and thus improve management of natural resources.     

四川省不同类型山洪灾害与主要影响因素的关系

以四川省为例,在明确溪河洪水及其引发的滑坡、泥石流三类山洪灾害分布格局的基础上,构建概念模型,分析降雨、地形、人口资产易损性等引发山洪灾害的基本因子和土壤、河网密度、土地利用等一般因子对不同类型山洪灾害的影响程度,并比较它们的异同。结果表明:(1)四川省山洪灾害主要分布在盆周山区、川西高原和横断山脉一带;(2)如果3项基本因子可以解释山洪灾害空间分布100%的变化,则它们对三类灾害的影响程度分别为:溪河洪水,降雨59%、地形28%、人口资产13%;泥石流,降雨15%、地形73%、人口资产12%;滑坡,降雨48%、地形34%、人口资产18%;(3)总体上,泥石流灾害对地形、岩性、土地利用等下垫面因子的依赖更高,而溪河洪水和滑坡灾害受降雨要素的影响更大。     

煤化工有机废水处理技术探讨—以煤制气项目为例

文章以煤制气项目为例,介绍了煤化工项目生产中有机废水的来源及特性,探讨了三种常用的煤化工废水处理方法。总结出多级生物处理法在煤制气有机废水处理的实用性,对今后煤制气有机废水处理的工作起到一定的指导意义。     

碳钢在自然海水和灭菌海水中的腐蚀行为分析

通过碳钢在自然海水和灭菌海水两种介质中的7 d暴露试验,比较了碳钢在自然海水和灭菌海水中腐蚀行为和腐蚀机理的差异。结果表明,微生物是影响碳钢腐蚀的重要因素,它影响到碳钢的腐蚀机理,同时会加重碳钢的局部腐蚀。     

聚氨酯缓冲材料在2种典型环境下的耐候性研究

目的 研究聚氨酯缓冲材料在湿热海洋和干热沙漠环境下的老化性能。方法 将3种不同表观密度的聚氨酯缓冲材料在万宁和敦煌试验站进行1 a的自然环境试验,探究聚氨酯缓冲材料外观、静态压缩性能、压缩永久变形性能和红外光谱的变化。结果 在1 a的自然环境试验中,材料压缩强度先增大后降低,压缩永久变形逐渐增大;在万宁试验站,样品表面出现发霉现象,密度为25、30、40 kg/m³的聚氨酯缓冲材料的压缩强度分别增大或衰减至106.4%、93.3%、87.5%,压缩永久变形分别增大109%、98%、138%;在敦煌试验站,密度为25、30、40 kg/m³的聚氨酯缓冲材料的压缩强度分别增大或衰减至106.4%、98.2%、97.8%,压缩永久变形分别增大55%、74%、93%。结论 聚氨酯缓冲材料在自然环境中会发生水解和热氧降解等老化反应,使材料性能出现下降。材料表观密度越大,性能衰减越快。材料对于湿热海洋环境更敏感,在万宁站的老化程度大于敦煌站。