我国电石法生产聚氯乙烯行业汞排放清单

提出了我国电石法聚氯乙烯(PVC)生产全生命周期汞排放清单的计算方法。采用低汞触媒有盐酸脱吸工艺、高汞触媒有盐酸脱吸工艺、高汞触媒无盐酸脱吸工艺的汞输入因子分别为0.045 g/kt、0.091 g/kt和0.122 g/kt,回收产品的汞输出分布因子分别为95.37%、81.97%和97.18%。估算得到:2010年我国电石法PVC生产汞输入量792.8~814.8 t;回收的产品汞705.9~724.4 t,通过大气无组织排放、管道残留以及其他未知途径汞排放79.6~82.8 t;废水汞排放1.3 t;固体废物汞排放3.6~3.7 t;废酸汞排放2.5~2.6 t。回收的产品汞是汞输出的主要途径。     

珠江口三维水质与底泥耦合模型的验证及应用

基于一维河网与三维河口耦合水动力模型,建立了可描述珠江口水体-底泥中营养盐动态变化的三维水质-底泥模型,利用1999年和2006年夏季观测数据对模型进行了验证,在此基础上,模拟分析了珠江口主要水质因子和底泥营养盐通量的分布特征,以及底泥通量对珠江口营养盐输入的贡献.验证结果表明,模型能较好地反映出水体和底泥中的营养盐及溶解氧浓度的时空分布特征,各水质因子的模拟值与观测值的相对误差均小于38%;另外,底泥营养盐通量的模拟值与文献报道的实测结果较为接近,表明模型能合理地刻画出底泥主要生化过程及通量变化特征.模拟结果显示,夏季珠江口氨氮(NH_4~+-N)和活性磷酸盐(PO_4~(3-)-P)通量主要从底泥向水体输送,底泥是水体氮磷元素的源,而硝态氮和亚硝态氮(NO_3~-+NO_2~-,NO23)的通量输送方向则与之相反,底泥呈现“汇”的效应;底泥营养盐通量主要从河口向外海递减,伶仃洋NH_4~+-N、NO23、PO_4~(3-)-P的通量变化范围分别为0.24~8.88、-10.06~-0.14、-0.37~0.41 mmol·m~(-2)·d~(-1),珠江口近海的通量变化范围分别为-0.01~4.14、-1.45~0.68、-0.12~0.09 mmol·m~(-2)·d~(-1).整体而言,底泥营养盐通量对珠江口营养盐输入有明显贡献,夏季经底泥释放进入水体的NH_4~+-N和PO_4~(3-)-P最大相当于陆源总氮、总磷输入量的12%和22%.     

Revealing the economic channels of natural impacts: an extended input–output subsystems application to GHG gases and water use

While a small set of economic activities generates most of the direct environmental burdens, the complexity of connections within an economic system requires consideration of the effects caused by the interdependences between its different agents. To date, however, the input–output (I–O) subsystems literature has been limited to uncovering the intersectoral linkages of direct and indirect environmental impacts within an economy and the connections between sectors and private consumption have thus not attracted much attention. This paper proposes an I–O subsystems model that endogenously incorporates not only production sectors but also household consumption to capture the entire channel of environmental impacts. The empirical application focuses on carbon dioxide equivalent (CO₂-eq.) emissions and water use associated with production sectors and households defined in the I–O table for a Spanish region, Extremadura. The results highlight the key role of the effects induced by private consumption on the environmental burdens of services.     

风浪扰动中太湖OA对水体磷循环影响的原位实验研究

在一次风速12 m.s-1的强风浪过程中,对太湖梅梁湾一浅水区水体有机聚集体（organic aggregates,OA）丰度、颗粒态有机质含量、碳、氮和磷含量等基本理化性质的变化情况进行了连续的原位监测和分析,同时分析了基本的水质指标.结果表明,风浪过程会对水体OA的理化性质及水体的磷循环产生极大的影响：在风浪过程中...     

喀斯特小流域生态治理下土壤养分特征分析——以广西都安县澄江小流域为例

选择广西典型喀斯特小流域,对生态治理过程中不同土地利用方式的土壤养分特征进行了研究和分析。结果表明棕色石灰土养分含量在经过石漠化治理后较1990年平均水平有所提高,用SPSS16.0对48个土壤样品的土壤养分进行主成分分析,得出2个主成分,并对土壤样品按不同土地利用方式得出的主成分分值进行排名,得分依次为乔木林灌木林沟谷耕地灌草丛草丛坡耕地。土地覆被好的区域土壤养分的含量高,土壤养分易于在植被较好的区域聚集。     

春季桑沟湾海域贝类养殖对海水中营养盐的影响研究

根据2011年春季对桑沟湾海域8个监测点的营养盐的变化特征和历史资料的研究,分析了桑沟湾水域溶解性无机氮(DIN)、总氮(TN)、活性磷酸盐(PO34-)和总磷(TP)浓度变化及它们之间的相互关系,估算了贝类养殖的排泄物对海水污染的贡献率。结果表明,溶解性无机氮的平均浓度为0.106 1 mg/L,NO3-N为主要存在形式,占溶解性无机氮平均含量的78.3%,NH3-N、NO2-N分别占溶解性无机氮平均含量的14.2%和7.5%。总氮的平均浓度为0.234 7 mg/L,溶解性无机氮浓度占总氮浓度的45.2%。活性磷酸盐的平均浓度为0.013 3 mg/L,总磷的平均浓度为0.024 78 mg/L。春季桑沟湾贝类养殖对该海域海水磷含量的贡献率比氮的贡献率大,N/P为17.63,营养水平基本属于贫营养。     

上海经济的直接物质投入和市内物质消耗

本文尝试对上海经济的直接物质投入和市内物质消耗进行初步的核算和分析,目的是促进上海"十一五"期间的循环经济发展和管理.采取的核算方法主要依据是欧盟统计局的<物质流账户及指标--方法导则>,而针对地区物质流核算的难点和上海的实际,也采用了一些估算方法.对核算的结果进行分析后表明,上海的物质自给率非常低,而直接物质投入1990-2005年总体上量现不断增长的态势,2005年达到45 564.95万t;人均直接物质投入已经相当高,2005年为33.50 t/人(以户籍人口计),1996年后已经高于1992-1996年发达国家中的较高水平;物质投入的生态效率比较低,每吨直接物质投入产出2005年为2 009.04元/t,2001年约为汉堡大都市区的1/5.     

Periphyton Nutrient Limitation and Maximum Potential Productivity in the Beaver Lake Basin,United States1

Ludwig, Andrea, Marty Matlock, Brian Haggard, and Indrajeet Chaubey, 2012. Periphyton Nutrient Limitation and Maximum Potential Productivity in the Beaver Lake Basin, United States. Journal of the American Water Resources Association (JAWRA) 48(5): 896‐908. DOI: 10.1111/j.1752‐1688.2012.00657.x Abstract: The objectives of this study were to measure periphytic growth responses to enrichment with nitrogen (N), phosphorus (P), and simultaneous N and P using in situ bioassays in streams draining Beaver Reservoir Basin, Northwest Arkansas; compare periphytic growth responses measured with in situ bioassays with a range of land use and point sources; and test the lotic ecosystem trophic status index (LETSI) as a simplifying metric to compare effects of nonpoint‐source pollutant‐limiting variables of N, P, and sediment across the basin. P limitation was observed at sites across a transect of stream orders throughout the basin; however, at the two sites with highest ambient nitrogen concentrations, limitation was often coupled with nitrogen limitation. Nutrients were at nonlimiting levels at both of two sites below wastewater treatment plants in all seasonal deployments. A Michaelis‐Menten growth equation described LETSI as a function of ambient PO₄‐P concentrations (p < 0.05); the midpoint (LETSI of 0.50) corresponded with a PO₄‐P concentration of approximately 3 μg/l. Change‐point analysis indicated a threshold point at LETSI of 0.80 and 15 μg/l PO₄‐P. These low values show that the periphytic community has a high affinity for available P, and that the watershed as a whole is sensitive to available nutrient inputs.     

Monitored and Modeled Correlations of Sediment and Nutrients with Chesapeake Bay Water Clarity

This article analyzes the correlations of the observed and modeled light attenuation coefficient, Kd, with in situ total suspended solids (TSS) and chlorophyll‐a concentrations in Chesapeake Bay (CB) tidal waters, and with sediment and nutrient loads from the Chesapeake watershed. Light attenuation is closely related to in situ TSS and chlorophyll‐a concentrations, however, the strength of the correlation differs among the CB segments. There are distinct differences between saline and tidal fresh segments in the main Bay, but less distinction among saline and tidal fresh segments in the tidal tributaries. The correlation between Kd with sediment and nutrient loads is complicated by the lag times of TSS and the chlorophyll‐a responses to reductions in nutrient and sediment loads from the watershed, and also due to the diverse load sources. Three sets of model sensitivity scenarios were performed with: (1) differential sediment and nutrient loads; (2) selective sediment source types; and (3) geographically isolated inputs. The model results yield similar findings as those based on observed data and provide information regarding the effect of sediment on specific water bodies. Based on the model results a method was developed to determine sediment and nutrient load reductions needed to achieve the water clarity standards of the CB segments.