非污染生态影响评价的生产力方法—以广东南亚热带地区为例

国家环境保护总局于1998年正式颁布实施非污染生态影响评价。非污染生态影响评价的方法很多，就以广东南亚热带地区为例研究非污染生态影响评价的生产力方法，并分析了这种方法的优点和存在的不足，以给区域建设项目的非污染生态影响评价提供借鉴。     

Parasitism in a social wasp: effect of gregarines on foraging behavior, colony productivity, and adult mortality

Behavior in eusocial insects likely reflects a long history of selection imposed by parasites and pathogens because the conditions of group living often favor the transmission of infection among nestmates. Yet, relatively few studies have quantified the effects of parasites on both the level of individual colony members and of colony success, making it difficult to assess the relative importance of different parasites to the behavioral ecology of their social insect hosts. Colonies of Polybia occidentalis, a Neotropical social wasp, are commonly infected by gregarines (Phylum Apicomplexa; Order Eugregarinida) during the wet season in Guanacaste, Costa Rica. To determine the effect of gregarine infection on individual workers in P. occidentalis, we measured foraging rates of marked wasps from colonies comprising both infected and uninfected individuals. To assess the effect of gregarines on colony success, we measured productivity and adult mortality rates in colonies with different levels of infection prevalence (proportion of adults infected). Foraging rates in marked individuals were negatively correlated with the intensity of gregarine infection. Infected colonies with high gregarine prevalence constructed nests with fewer brood cells per capita, produced less brood biomass per capita, and, surprisingly, experienced lower adult mortality rates than did uninfected or lightly infected colonies. These data strongly suggest that gregarine infection lowers foraging rates, thus reducing risk to foragers and, consequently, reducing adult mortality rates, while at the same time lowering per-capita input of materials and colony productivity. In infected colonies, queen populations were infected with a lower prevalence than were workers. Intra-colony infection prevalence decreased dramatically in the P. occidentalis population during the wet season.An erratum to this article can be found at     

土地生产潜力的计算方法

本文通过对国外土地生产潜力计算方法的评述,展示了这一领域的研究前沿和发展动态,提出了今后的努力方向。     

Dynamics of Restoration Processes in the Idle Solonetz Ecosystems in the Southern Transural Region

The initial period of idleness in the solonetz ecosystems of the southern Transural Region is characterized by a significant variability of their soil–plant communities, which is determined by natural periodicity and general direction of the process of ecosystem restoration. Selective consumption of salinizing ions by the plants growing on idle land activates the development of desalinization processes.     

UNITANK工艺降低污泥产率操作的可行性研究

随着改善环境的需求和污水处理行业的发展,污水处理产生的污泥的处置已经成为行业急待解决的问题,无论何种方式的污泥处置都极大地增加了企业的运营成本.针对UNITANK工艺分析了工艺运行的操作特点,并根据SBR反应器中进水与曝气方式对活性污泥产率的影响这一实验结论,论述了UNITANK工艺降低污泥产率操作的可行性.通过对UNITANK工艺进水和曝气阶段操作模式的选择确定工艺操作参数,并对生产采取过程控制,降低污泥产率这一目标是可以达到的.     

我国南方不同类型草地生产力及对气候变化的响应

为进一步明晰南方不同类型草地的碳源汇关系,预测未来气候情景下可能的碳循环特征,利用本地参数化的BIOME-BGC模型对2001~2010年低山丘陵草原化草甸、典型草山草坡和典型山地草甸样地净初级生产力(NPP)与净生态系统生产力(NEP)进行了模拟估算。不同类型草地的NPP和NEP 10年间变化趋势不同,低山丘陵草原化草甸、典型草山草坡和典型山地草甸的NPP平均值分别为357.17、232.4和191.96gC/(m2·a);NEP的平均值分别为3.25、21.28和81.96gC/(m2·a)。3种类型草地NPP与温度之间存在显著的正相关关系,NEP与温度之间存在着显著的负相关关系;本模型模拟的NPP和NEP与年平均降水量之间相关性不明显。未来气候情景C1P-1T1下(CO2浓度倍增,年均温增加2℃,降水减少10%),低山丘陵草原化草甸样地NPP增加26.93%,NEP增加160%;典型草山草坡样地NPP增加62.20%,NEP增加153%;典型山地草甸样地NPP增加135%,NEP增加206%。3种南方草地类型在未来气候情景下都将有一定的碳汇增长潜力,其中以典型山地草甸的碳汇潜力最为明显,与降水量相比受温度变化的影响相对较大。     

混交林的改土效益及其在防止地力衰退上的应用

讨论了人工混交林对林地土壤理化性质、微生物及水土保持等方面的改良和促进作用。针对目前人工纯林地力衰退的问题，提出了混交林可作为防止地力衰退的途径， 并对混交林应用上的有关问题作了探讨。     

Distribution of total mercury and methylmercury in lake sediments in Arctic Ny-Ålesund

The toxicities and bioavailabilities of total mercury (THg) and methylmercury (MeHg) in aquatic systems have made them the subjects of recent research. In this study, we collected a lake sediment core from Ny-Ålesund in Svalbard and analyzed the distributions of THg and MeHg in the sediments. The increased trend of THg was caused by anthropogenic contamination since the 14th century through long-range transportation, especially after the industrial era. However, the peak values of Hg in surface sediment samples could be explained by the increased algal scavenging process in recent decades. All the biogeochemical proxies (e.g., pigments and diatom biomass) revealed recent sharp increases in aquatic primary production due to the current climate warming. Rock-Eval analyses indicated that algal-derived organic matter took up a large portion, and quantitative calculation showed that 89.6-95.8% of the Hg in post-1950 could be explained by scavenging. The distribution of MeHg has a close relationship with total Hg and organic matter. The oxidation-reduction condition is one of the possible factors affecting the methylation rates in H2 lake sediments. Higher algal productivity and organic matter actually led to the increased trend of methylation in the uppermost sediment. This study supports some new key hypotheses on climate-driven factors affecting Hg and MeHg cycling in High Arctic lake sediments.     

水资源足迹计算模型研究——以南京市为例

在生态足迹理论的基础上探讨了水资源足迹的概念。基于水资源生产力,推导出水资源足迹和水资源承载力的计算公式,用水资源赤字和水资源盈余来衡量水资源利用的可持续性。以南京市为例进行模型实证研究,计算了2003～2007年南京市水资源足迹和水资源承载力,结果表明南京市水资源足迹增长明显,水资源承载力总体平稳,赤字从2004—2007年呈指数增长趋势。实证研究表明模型结果可以在一定程度上衡量生产消费对水资源的影响。     

生产性公共支出、空间溢出效应与区域经济差距——基于多地区动态一般均衡模型的分析

改革开放以来,中国东、中、西部地区经济差距不断拉大,政府为协调区域经济发展水平,逐渐将生产性公共支出向较不发达的中部和西部地区倾斜。为了全面地评估这种财政政策的效果,在传统一般均衡分析的基础上将生产性公共支出及其空间溢出纳入宏观经济分析框架,构建了一个多地区动态一般均衡模型,并用该模型模拟了现实经济中区域生产性公共支出政策及其调整对区域经济和宏观经济的冲击,得到的结论是:(1)当前生产性公共支出空间分布基础上,新增生产性公共支出分散于各个地区,会继续扩大区域经济差距;(2)新增生产性公共支出集中于较不发达的地区时,由于较低的基础设施边际生产力和较弱的空间溢出效应,全国人均产出不能达到最大水平,但可缩小区域经济差距;(3)新增生产性公共支出集中于较发达的地区时,由于较高的基础设施边际生产力和较强的空间溢出效应,全国人均产出可达到最大水平,但同时拉大区域经济差距。由此得到的政策启示是:在现有生产性公共支出的区域分布基础上,以缩小区域经济差距为目标的次优的财政政策将新增的生产性公共支出向西部和中部等较不发达地区倾斜,靠直接刺激效应促进当地产出增长;以效率优先为准则的财政政策选取较发达地区为生产性公共支出目的地,因为较发达地区通常具有较高的基础设施边际生产力和较强的空间溢出效应。