Locating Spatial Variation in the Association Between Wildland Fire Risk and Social Vulnerability Across Six Southern States

Wildland fire in the South commands considerable attention, given the expanding wildland urban interface (WUI) across the region. Much of this growth is propelled by higher income retirees and others desiring natural amenity residential settings. However, population growth in the WUI increases the likelihood of wildfire fire ignition caused by people, as humans account for 93% of all wildfires fires in the South. Coexisting with newly arrived, affluent WUI populations are working class, poor or otherwise socially vulnerable populations. The latter groups typically experience greater losses from environmental disasters such as wildfire because lower income residents are less likely to have established mitigation programs in place to help absorb loss. We use geographically weighted regression to examine spatial variation in the association between social vulnerability (SOVUL) and wildfire risk. In doing so, we identify “hot spots” or geographical clusters where SOVUL varies positively with wildfire risk across six Southern states—Alabama, Arkansas, Florida, Georgia, Mississippi, and South Carolina. These clusters may or may not be located in the WUI. These hot spots are most prevalent in South Carolina and Florida. Identification of these population clusters can aid wildfire managers in deciding which communities to prioritize for mitigation programming.     

城市污水厂二级处理出水深度处理组合工艺研究

为了研究臭氧-曝气生物滤池二级处理出水深度处理组合工艺的处理效果,采用臭氧-曝气生物滤池(biological aerated filter, BAF)组合工艺对城市污水处理厂二级生化处理出水进行深度处理。结果表明,组合工艺对造成水中色度的主要物质腐植酸和富里酸类有机物和嗅味物质中的二甲基三硫和二甲基异莰醇(MIB)能够进行有效去除。臭氧氧化能够显著提高后续BAF单元对COD_Mn的去除。在进水COD_Mn6~8 mg/L、色度为25~30度、浊度约为8 NTU的条件下,当臭氧投加量为5~6 mg/L、BAF的水力停留时间为1~1.5 h时,出水COD_Mn< 5 mg/L、色度<5度、浊度<1 NTU,出水水质可满足生产工艺对回用水的水质要求。     

Impact of anthropogenic emissions and open biomass burning on regional carbonaceous aerosols in South China

Carbonaceous aerosols were studied at three background sites in south and southwest China. Hok Tsui in Hong Kong had the highest concentrations of carbonaceous aerosols (OC = 8.7 ± 4.5 μg/m³, EC = 2.5 ± 1.9 μg/m³) among the three sites, and Jianfeng Mountains in Hainan Island (OC = 5.8 ± 2.6 μg/m³, EC = 0.8 ± 0.4 μg/m³) and Tengchong mountain over the east edge of the Tibetan Plateau (OC = 4.8 ± 4.0 μg/m³, EC = 0.5 ± 0.4 μg/m³) showed similar concentration levels. Distinct seasonal patterns with higher concentrations during the winter, and lower concentrations during the summertime were observed, which may be caused by the changes of the regional emissions, and monsoon effects. The industrial and vehicular emissions in East, Southeast and South China, and the regional open biomass burning in the Indo-Myanmar region of Asia were probably the two major potential sources for carbonaceous matters in this region.     

高锰酸盐复合药剂强化混凝改善再生水景观湖水质研究

实验通过投加助凝剂以强化混凝沉淀过程,从而达到去除再生水景观水中的藻类。以PAC为混凝剂,高锰酸盐复合药剂(PPC)为预氧化助凝剂,通过烧杯实验确定PPC、PAC同时投加,最佳投量分别为1 mg/L、60 mg/L。生产性实验中,机械加速澄清池强化混凝对TP、叶绿素、藻密度的去除率分别为54%、32.3%和35.4%,湖水中TP、TN逐渐降低分别由4.9 mg/L、23 mg/L降至0.72 mg/L、10.3 mg/L。PPC提高了混凝沉淀对藻类的去除效果,改善了再生水景观湖水质,降低水中氮磷营养盐的含量。     

Hexabromocyclododecanes in surface sediments and a sediment core from Rivers and Harbor in the northern Chinese city of Tianjin

In the present study, hexabromocyclododecanes (HBCDs) were investigated in the sediment from Haihe River (HR), Dagu Dainage Canal (DDC) and Tianjin Harbor (TH) at Bohai Bay using a total of 51 samples of surface sediments and a sediment core collected from May to September in 2010, and its diastereomer- and enantiomer-specific profiles were analyzed. The concentration of total HBCDs were generally high, with mean value and ranges of 31.0 and 1.35–634 ng g^?1 dw, respectively. The contamination followed the order of TH > DDC > HR. Higher levels (up to 634 ng g^?1 dw) occurred in the lower reach of HR and DDC located in an industrial area of Tianjin. This is the first time to report so high concentration of HBCDs in sediment in Southeast Asia. The γ-diastereomer dominated in most samples (44 out of 51), and this is in agreement with the diastereomer distribution pattern in industrial products, while α-HBCD was the dominant diastereomer in the other seven samples. However, only few samples exhibited γ-diastereomer ratio similar to that (75–89%) in technical products, indicating the inter-transformation and variable degradation of the different isomers. The high ratio of γ-diastereomer could be used as an indicator for fresh contamination input. Enantiomeric factors (EFs) of HBCD isomers in most of the samples were statistically different from technical products (p < 0.05), showing a trend of more easily enrichment of the (?)-HBCD-enantiomer compared to the (+)-HBCD-enantiomer. The δ- and ε-diastereomers were frequently detected but at low level. The HBCDs in the sediment core showed several peaks, and the greatest value occurred in 2005, when a plastic manufacture plant using HBCD was set up nearby.     

Hexabromocyclododecanes in limnic and marine organisms and terrestrial plants from Tianjin,China: Diastereomer- and enantiomer-specific profiles,biomagnification, and human exposure

To interpret the distribution of hexabromocyclododecanes (HBCDs) in various organisms, we measured the concentrations and diastereomer and enantiomer profiles of HBCDs in 21 different species of limnic and marine cohorts from Tianjin, China. The concentration ranges of HBCDs in limnic and marine organisms were 64.3–1111 ng g⁻¹ lw and 85.5–989 ng g⁻¹ lw, respectively. Living habitat and feeding habits had important impacts on HBCD diastereomer distribution. Most of the species appeared to preferentially select (+)-α-, (−)-β- and (−)-γ-HBCD. There is a tendency that the total and α-HBCDs were magnified as trophic level increased with trophic magnification factors (TMFs) around 2. The concentrations of HBCDs in the limnic and marine fishes were highest in the liver, followed by the gill, skin, and muscle. In terrestrial plants, the highest concentrations of HBCDs were observed in the leaf, followed by the root and the rhizosphere soil. Plants showed enantioselectivity for HBCD enantiomers, which varied with plant species and organs (leaf vs. root) of the same plant. Higher estimated daily intakes (EDIs) of HBCDs were observed from fish than from wheat.     

Levels and distribution of Dechlorane Plus in coastal sediments of the Yellow Sea, North China

Dechlorane Plus (DP) has been determined in surface sediments from three Chinese coastal bays, e.g. Jiaozhou, Sishili and Taozi Bay in North China. DP concentrations ranged from <1.2 to 187 pg g⁻¹ dry weight (dw) (mean: 24.7 pg g⁻¹ dw) in Jiaozhou Bay, <1.2 to 135 pg g⁻¹ dw (mean 69.9 pg g⁻¹ dw) in Sishili Bay and <1.2 to 66.7 pg g⁻¹ dw (mean: 40.4 pg g⁻¹ dw) in Taozi Bay, respectively. Additionally, two dechlorinated species were quantified, which accounted for 0.6-5.1% of the ∑DP concentration.The f_syn values (syn-isomer/(syn- + anti-isomer)) in sediments from Jiaozhou Bay (mean 0.29) were close to the technical DP mixture (0.2-0.4), probably indicating local inputs of DP. In contrast, sediments in Sishili and Taozi Bay showed much lower f_syn values (mean 0.16). During transportation the DP isomers are subject to stereo selective degradation which partly resulted in the relative enrichment of anti-DP in coastal sediments.     

初始pH值对磷酸盐还原除磷的影响研究

以超高盐（盐度7％,以NaCI计）高磷榨菜废水为研究对象,考察了初始pH值对磷酸盐还原进程的影响。实验结果表明,初始pH值对磷酸盐还原除磷效能影响显著。初始pH为8时,磷酸盐还原除磷率达到最高,平均值为65．45％。同时,初始pH值还会影响污泥中活性磷的形成以及基体对磷化氢的吸附。此外,偏碱性有利于磷形态转化,且BD-P（主要是一些可溶性的、还原性强的、带有Fe-P化合物的集合）含量的高低调控着生物膜内间隙水中溶解态可反应性磷（DRP）和可还原水溶态磷（RSP）含量,最终决定着磷酸盐还原进程。随着初始pH值的升高,污泥对磷化氢的吸附能力降低导致污泥中结合态磷化氢（MBP）含量不断减少。     

Polychlorinated naphthalenes (PCNs) in riverine and marine sediments of the Laizhou Bay area, North China

PCN congeners were analyzed in marine and riverine sediments of the Laizhou Bay area, North China. Concentrations of PCNs ranged from 0.12 to 5.1 ng g⁻¹ dry weight (dw) with a mean value of 1.1 ng g⁻¹ dw. The levels of PCNs varied largely, with industrial group approximately ten folds higher than those of the rural in riverine sediment. A strong impact by direct discharge from local factories was suggested. Similar compositional profiles were found within groups. High resemblance of compositional profiles between industrial samples and Halowax 1014 was observed. It was indicated that PCNs in riverine sediments were mainly from release of industrial usage, with additional contributions from industrial thermal process at certain sites. In marine sediments, it was suggested that PCNs along the coast of Laizhou Bay were mainly controlled by riverine input. While in the central bay, PCN distributions were possibly impacted by combined multiple factors.     

Impacts of invasive plants on ecosystems in natural reserves in Jiangsu of China

To estimate the impacts of invasive plants on ecosystems, a survey has been conducted in three sites including both buffer zones and core zones. 13, 19 species are found in the Yuntai Mountain and Longchi Mountain natural reserve respectively, and 23 in the Purple Mountain Natural Park. Altogether 25 species belonging to 12 families, the majority of which are native to North America, some of them have set up stable reproducible populations. Among them, Solidago canadensis is found in Longchi Mountain and Purple Mountain. Communities of Galinsoga parviflora, Gynura crepidioides, Ageratum conyzoides, and Ambrosia artemisiifolia pose a serious threat to local biodiversity.