Unveiling the overlooked microbial niches thriving on building exteriors.

Rapid urbanization in the Asia-Pacific region is expected to place two-thirds of its population in concrete-dominated urban landscapes by 2050. While diverse architectural facades define the unique appearance of these urban systems. There remains a significant gap in our understanding of the composition, assembly, and ecological potential of microbial communities on building exteriors. Here, we examined bacterial and protistan communities on building surfaces along an urbanization gradient (urban, suburban and rural regions), investigating their spatial patterns and the driving factors behind their presence. A total of 55 bacterial and protist phyla were identified. The bacterial community was predominantly composed of Proteobacteria (33.7% to 67.5%). The protistan community exhibited a prevalence of Opisthokonta and Archaeplastida (17.5% to 82.1% and 1.8% to 61.2%, respectively). The composition and functionality of bacterial communities exhibited spatial patterns correlated with urbanization. In urban buildings, factors such as facade type, light exposure, and building height had comparatively less impact on bacterial composition compared to suburban and rural areas. The highest bacterial diversity and lowest Weighted Average Community Identity (WACI) were observed on suburban buildings, followed by rural buildings. In contrast, protists did not show spatial distribution characteristics related to facade type, light exposure, building height and urbanization level. The distinct spatial patterns of protists were primarily shaped by community diffusion and the bottom-up regulation exerted by bacterial communities. Together, our findings suggest that building exteriors serve as attachment points for local microbial metacommunities, offering unique habitats where bacteria and protists exhibit independent adaptive strategies closely tied to the overall ecological potential of the community.

Plasma Cell-Free Adenomatous Polyposis Coli Gene Promoter Methylation as a Prognostic Biomarker for Hepatocellular Carcinoma.

INTRODUCTION: Hepatocellular carcinoma (HCC) is a leading cause of cancer death worldwide. Lack of biomarkers for follow-up after treatment is a clinical challenge. DNA methylation has been proposed to be a potential biomarker in HCC. However, there is still lacking of evidence of its clinical use. This study aims to evaluate the value of using plasma Adenomatous Polyposis Coli promoter methylation level (APC-MET) as a potential biomarker in HCC treatment. METHOD: A total of 96 patients with HCC at BCLC stage B underwent local tumor ablation treatment were prospectively included in this study. APC-MET was examined from the plasma of each patient before and 1 months after treatment. The prediction value of APC-MET for survival outcome and disease status after treatment were analyzed, and adjusted with alpha-fetoprotein and protein induced by vitamin K absence-II using cox regression analysis. RESULTS: Univariate cox regression analysis showed preoperative APC-MET >0 (HR, 2.9, 95% CI 1.05－8.05, p=0.041) and postoperative APC-MET >0 (HR, 3.47, 95% CI 1.16－10.4, p=0.026) were both predictors of death, and preoperative APC-MET >0 was a predictor of disease progression after treatment (HR, 2.04, 95% CI 1.21－3.44, p=0.007). In multivariate models, pre-op APC-MET >0 was a significant predictor of disease progression after adjusting with other two traditional biomarkers (HR, 1.82, 95% CI 1.05－3.17, p=0.034). CONCLUSIONS: Hypermethylation of APC promoter appears to be a potential biomarker that could predict patient survival and disease progression outcome in patients with intermediate stage HCC after local ablation treatment.

Differences in organic carbon accumulation in mangrove soils due to foraging by herbivorous crabs.

Crabs in mangroves could enhance the transfer of organic carbon (OC) from leaf litter to soils, whose variation with the difference in crab size is, however, not well known. A 32-day laboratory feeding experiment was conducted to explore the effects of different sizes of the crabs Parasesarma plicatum foraging on leaf litter of Kandelia obovata on OC accumulation in mangrove soils. Mean rates of soil OC accumulation due to leaf foraging by large, medium, and small crabs were 21.11, 16.11, and 0.77 mg C ind-1 d-1, corresponding to the rates of OC removal from leaf litter of 62.60%, 51.37%, and 2.19%, respectively. Large and medium crabs ingested larger amounts of leaf litter, and soil OC accumulation rates resulting from leaf foraging by large and medium crabs were approximately 8 times higher than those by leaf litter decomposition and triple those by non-leaf foraging. Small crabs ingested the smallest amount of leaf litter, which was almost used for their growth and metabolism. These results underline the key ecological roles of leaf foraging by crabs, especially those with large and medium sizes, in OC accumulation in mangrove soils, which is conducive to estimating carbon sequestration in mangrove soils.

Aboveground plants determine the exchange of pathogens within air-phyllosphere-soil continuum in urban greenspaces.

The microbiome in the air-phyllosphere-soil continuum of urban greenspaces plays a crucial role in re-connecting urban populations with biodiverse environmental microbiomes. However, little is known about whether plant type affects the airborne microbiomes, as well as the extent to which soil and phyllosphere microbiomes contribute to airborne microbiomes. Here we collected soil, phyllosphere and airborne microbes with different plant types (broadleaf tree, conifer tree, and grass) in urban parks. Despite the significant impacts of plant type on soil and phyllosphere microbiomes, plant type had no obvious effects on the diversity of airborne microbes but shaped airborne bacterial composition in urban greenspaces. Soil and phyllosphere microbiomes had a higher contribution to airborne bacteria in broadleaf trees (37.56%) compared to conifer trees (9.51%) and grasses (14.29%). Grass areas in urban greenspaces exhibited a greater proportion of potential pathogens compared to the tree areas. The abundance of bacterial pathogens in phyllosphere was significantly higher in grasses compared to broadleaf and conifer trees. Together, our study provides novel insights into the microbiome patterns in air-phyllosphere-soil continuum, highlighting the potential significance of reducing the proportion of extensively human-intervened grass areas in future urban environment designs to enhance the provision of ecosystem services in urban greenspaces.

DNA Methylation Biomarkers as Prediction Tools for Therapeutic Response and Prognosis in Intermediate-Stage Hepatocellular Carcinoma.

INTRODUCTION: Alfa-fetoprotein (AFP), as the main serum tumor marker of hepatocellular carcinoma (HCC), is limited in terms of specificity and ability to predict outcomes. This study investigated the clinical utility of DNA methylation biomarkers to predict therapeutic responses and prognosis in intermediate-stage HCC. METHODS: This study enrolled 72 patients with intermediate-stage HCC who underwent locoregional therapy (LRT) between 2020 and 2021. The immediate therapeutic response and disease status during a two-year follow-up were recorded. Analysis was performed on 10 selected DNA methylation biomarkers via pyrosequencing analysis of plasma collected before and after LRT. RESULTS: Analysis was performed on 53 patients with complete responses and 19 patients with disease progression after LRT. The mean follow-up duration was 2.4 ± 0.6 years. A methylation prediction model for tumor response (MMTR) and a methylation prediction model for early progression (MMEP) were constructed. The area under the curve (AUC) for sensitivity and specificity of MMTR was 0.79 for complete response and 0.759 for overall survival. The corresponding AUCs for sensitivity and specificity of AFP and protein induced by vitamin K absence-II (PIVKA-II) were 0.717 and 0.708, respectively. Note that the MMTR index was the only significant predictor in multivariate analysis. The AUC for sensitivity and specificity of the MMEP in predicting early progression was 0.79. The corresponding AUCs for sensitivity and specificity of AFP and PIVKA-II were 0.758 and 0.714, respectively. Multivariate analysis revealed that platelet count, beyond up-to-7 criteria, and the MMEP index were strongly correlated with early tumor progression. Combining the indexes and serum markers further improved the predictive accuracy (AUC = 0.922). Multivariate analysis revealed the MMEP index was the only independent risk factor for overall survival. DISCUSSION/CONCLUSIONS: This study indicates that these methylation markers could potentially outperform current serum markers in terms of accuracy and reliability in assessing treatment response and predicting outcomes. Combining methylation markers and serum markers further improved predictive accuracy, indicating that a multi-marker approach may be more effective in clinical practice. These findings suggest that DNA methylation biomarkers may be a useful tool for managing intermediate-stage HCC patients and guiding personalized treatment, particularly for those who are at high risk for close surveillance or adjuvant treatment after LRT.

Flooding drives the temporal turnover of antibiotic resistance gene in manure-amended soil-water continuum.

Rice paddy soil is a hotspot of antibiotic resistance genes (ARGs) due to the application of organic fertilizers. However, the temporal dynamics of ARGs in rice paddy soil and its flooded water during the growing season remain underexplored. In this study, a microcosm experiment was conducted to explore the ARG profiles in a long term (130 days) flooded two-phase manure-amended soil-water system. By using high-throughput quantitative PCR array, a total of 23-98 and 34-85 ARGs were detected in the soil and overlying water, respectively. Regression analysis exhibited significant negative correlations between ARG profile similarities and flooding duration, indicating that flooding significantly altered the resistome (P < 0.001). This finding was validated by the increased ARG abundance in the soil and the overlying water, for example, after 130 days flooding, the abundance of ARGs in CK soil was increased from 0.03 to 1.20 copies per 16S rRNA. The PCoA analysis further suggested pig manure application resulted in distinct ARG profiles in the soil-water continuum compared with those of the non-amended control (Adonis, P < 0.05). The Venn diagram showed that all ARGs detected in the pig manure were present in the treated soil. Twelve ARGs (e.g., sul1) were shared among the pig manure, manure-amended soil, and overlying water, indicating that certain manure- or soil-borne ARGs were readily dispersed from the soil to the overlying water. Moreover, the enhanced relationships between the ARGs and mobile genetic elements in pig manure applied soil-water continuum indicate that the application of organic matter could accelerate the emergence and dissemination of ARGs. These findings suggested that flooding represents a crucial pathway for dispersal of ARGs from the soil to the overlying water. Identification of highly mobile ARGs in the soil-water continuum is essential for assessing their potential risk to human health and promoting the development of sustainable agricultural practices to mitigate their spread.

Distribution and Transformation of Mercury in Subtropical Wild-Caught Seafood from the Southern Taiwan Strait.

Wild-caught seafood contains significant amounts of mercury. Investigating the mercury accumulation levels in wild-caught seafood and analyzing its migration and transformation are of great value for assessing the health risks of mercury intake and for the tracking of mercury sources. We determined the concentrations and stable mercury isotopic compositions (δ202Hg, Δ199Hg, Δ200Hg, and Δ201Hg) of 104 muscle samples collected from 38 species of seafood typically harvested from the Taiwan Shallow Fishing Ground (TSFG), Southern Taiwan Strait. Overall, the concentrations of total mercury (THg) and methylmercury (MeHg) ranged from 11 to 479 ng/g (dry weight, dw) and 10 to 363 ng/g (dw), respectively, and were below the threshold value established by the USEPA and the Chinese government. Demersal and near-benthic species accumulated more mercury than pelagic or mesopelagic species. The characteristics of mercury isotopes in wild-caught marine species differed in terms of vertical and horizontal distribution. Considering the known peripheral land sources of mercury (Δ199Hg ≈ 0), the mercury in seafood from the TSFG (Δ199Hg > 0) did not originate from anthropogenic emissions. The ratio of Δ199Hg and Δ201Hg (1.18 ± 0.03) suggested that the photoreduction of Hg (II) and the photo-degradation of MeHg equally contributed to mass-independent fractionation. Based on the values of Δ199Hg/δ202Hg (1.18 ± 0.03), about 67% of the mercury in seawater had undergone microbial demethylation prior to methylation and entering the seafood. Additionally, the vertical distribution of Δ200Hg in seafood from different water depths implies that mercury input was in part caused by atmospheric deposition. Our results provide detailed information on the sources of mercury and its transfer in the food web in offshore fishing grounds.

Urbanization minimizes the effects of plant traits on soil provisioned ecosystem services across climatic regions.

An increasingly urbanized world is one of the most prominent examples of global environmental change. Across the globe, urban parks are designed and managed in a similar way, resulting in visually pleasing expansions of lawn interspersed with individually planted trees of varying appearances and functional traits. These large urban greenspaces have the capacity to provide various ecosystem services, including those associated with soil physicochemical properties. Our aim was to explore whether soil properties in urban parks diverge underneath vegetation producing labile or recalcitrant litter, and whether the impact is affected by climatic zone (from a boreal to temperate to tropical city). We also compared these properties to those in (semi)natural forests outside the cities to assess the influence of urbanization on plant-trait effects. We showed that vegetation type affected percentage soil organic matter (OM), total carbon (C) and total nitrogen (N), but inconsistently across climatic zones. Plant-trait effects were particularly weak in old parks in the boreal and temperate zones, whereas in young parks in these zones, soils underneath the two tree types accumulated significantly more OM, C and N compared to lawns. Within climatic zones, anthropogenic drivers dominated natural ones, with consistently lower values of organic-matter-related soil properties under trees producing labile or recalcitrant litter in parks compared to forests. The dominating effect of urbanization is also reflected in its ability to homogenize soil properties in parks across the three cities, especially in lawn soils and soils under trees irrespective of functional trait. Our study demonstrates that soil functions that relate to carbon and nitrogen dynamics-even in old urban greenspaces where plant-soil interactions have a long history-clearly diverged from those in natural ecosystems, implying a long-lasting influence of anthropogenic drivers on soil ecosystem services.

Evergreen trees stimulate carbon accumulation in urban soils via high root production and slow litter decomposition.

Urban soils can, when not sealed, store a considerable amount of carbon (C) especially under cool climates. Soil C sequestration is controlled by plant functional type, but the mechanisms by which plant types affect C accumulation in urbanised settings is poorly known. We selected 27 urban parks of varying ages (young: 5-15, old: >70 years) and 10 reference forests (>80 years) in southern Finland to study whether the ability of soils to store C relates to (i) the decomposition rate of different litter types (recalcitrant vs. labile), and/or (ii) organic matter (OM) input via root production among three common plant functional types (deciduous trees, evergreen trees, grass/lawn). Our results suggest that the high soil C accumulation under evergreen trees can result from low needle litter decomposability, accompanied by a low soil CO2 efflux. Furthermore, high root production by evergreen trees compared to deciduous trees and lawns, likely reflects the high % OM under evergreen trees. We showed that plant effects on C inputs and outputs are modulated, either directly or indirectly, by park age so that these effects are accentuated in old parks. Our results suggest that despite the capacity of evergreen trees to accumulate C in soils in urban parks, this capacity is far less compared to soils in forests of the same age. OM content under deciduous trees did not differ between old parks and reference forests, suggesting that the raking of leaves in the fall has a surprisingly small impact on OM and C accumulation in urban parks. Soil OM content is an important measure that controls various ecosystem services in cities and elsewhere. Therefore, increasing the proportion of evergreen trees in urban parks in cool cities is a good option to boost the ecosystem services capacity in the often strongly disturbed urban soils.

Soil sealing causes substantial losses in C and N storage in urban soils under cool climate.

Urban soil can store large amounts of carbon (C) and nitrogen (N). To accurately estimate C and N storage in urban soils, C and N contents underneath impervious surfaces - the most prevalent land cover type in cities - should be taken into account. To date, however, only few studies have reported urban soil C and N content underneath impervious surfaces, and no data exist for cities under cold/cool climates, such as the Boreal zone. Here, we studied, for the first time, the effects of sealing on soil C and N storage in a Boreal city. Sealed soils were sampled for physico-chemical and biological parameters from 13 sites in the city of Lahti, Finland, at three depths (0-10 and 45-55 cm, representing the construction layer composed of gravel, other moraine material and crushed rock, and the native soil layer beneath the ca. 1 m thick construction layer). Our results show that urban soils underneath impervious surfaces in Finland contain 11 and 31 times less C and N content, respectively, compared with warmer regions. This is due to a deep C and N deficient construction layer below sealed surfaces. Even though impervious surfaces cover ca. twice the area of pervious surfaces in the centre of Lahti, we estimate that only 6% and 4% of urban soil C and N, respectively, are stored underneath them. Furthermore, we found very little C and N accumulation underneath the sealed surfaces via root growth and/or leakage through ageing asphalt. Our results show that soil sealing, in concert with a massive top soil removal typical to cold climates, induces a considerable loss of C and N in Boreal urban areas.

Cell-free methylation markers with diagnostic and prognostic potential in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is a highly malignant tumor with poor prognosis and high mortality. There is a dearth of effective early diagnostic tools, so liver resection surgery and liver transplantation are the only effective medical treatments. The most commonly used marker for HCC detection is serum alpha fetoprotein (AFP), which has low sensitivity and specificity. Because aberrant DNA methylation of genes and miRNAs occurs early in most cancers, we explored whether circulating methylation markers could be promising clinical tools for HCC diagnosis. Using a whole-genome approach, we identified many hyper-methylated miRNAs in HCC. Furthermore, three abnormally methylated genes and one miRNA were combined to establish a methylation predictive model and tested for its diagnostic and prognostic potential in HCC. Using plasma samples, the predictive model exhibited high sensitivity and specificity (> 80%) for HBV-related HCC. Most importantly, nearly 75% of patients who could not be diagnosed with AFP at 20 ng/mL were detected by this model. Further, the predictive model exhibited an exceedingly high ability to predict 5-year overall survival in HCC patients. These data demonstrate the high diagnostic and prognostic potential of methylation markers in the plasma of HCC patients.

Frequent DNA methylation of MiR-129-2 and its potential clinical implication in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is a highly malignant tumor with poor prognosis and high mortality due to a lack of effective medical treatment and apparent early stage symptoms. Understanding molecular mechanism of cancer development is crucial for HCC diagnosis, prognosis, and treatment. Recently, microRNAs have been shown to play an important role in carcinogenesis, being regulated by DNA methylation in several cases. In this study, a whole genome approach was used to identify methylation-regulated miRNAs in HCC, finally focusing on miR-129-2. MiR-129-2 methylation and reduced expression were observed in all examined HCC cell lines but not in normal liver cells and tissues. In 39 (93%) of 42 HCC, the methylation levels of miR-129-2 were significantly increased in tumor tissues compared with adjacent normal tissues. Furthermore, miR-129-2 methylation was detectable in plasma samples from HCC patients, but not in plasma samples from healthy individuals or patients with liver cirrhosis. At a cut-off value of -2.36 (log2 transformation of methylation level), it was possible to distinguish HCC from healthy and cirrhotic controls with sensitivity and specificity of 88% and 100%, respectively. This study indicates that miR-129-2 methylation is highly accurate in distinguishing HCC patients from cirrhosis patients and healthy individuals, implying its potential utility as an early diagnostic marker for HCC.

Aberrant methylation impairs low density lipoprotein receptor-related protein 1B tumor suppressor function in gastric cancer.

DNA methylation plays a significant role in tumor progression. In this study, we used CpG microarray and differential methylation hybridization approaches to identify low density lipoprotein receptor-related protein 1B (LRP1B) as a novel epigenetic target in gastric cancer. LRP1B was hypermethylated in four gastric cancer cell lines, and low LRP1B mRNA expression was associated with high methylation levels in gastric cancer cell lines. Addition of a DNA methylation inhibitor (5-Aza-dC) restored the mRNA expression of LRP1B in these cell lines, indicating that DNA methylation is involved in regulating LRP1B expression. In 45 out of 74 (61%) clinical samples, LRP1B was highly methylated; LRP1B mRNA expression was significantly lower in 15 out of 19 (79%, P < 0.001) gastric tumor tissues than in corresponding adjacent normal tissues. In addition, ectopic expression of mLRP1B4 in gastric cancer cell lines suppressed cell growth, colony formation and tumor formation in nude mice. These results collectively indicate that LRP1B is a functional tumor suppressor gene in gastric cancer and that is regulated by DNA methylation.

Glutamate receptor, ionotropic, kainate 2 silencing by DNA hypermethylation possesses tumor suppressor function in gastric cancer.

Aberrant DNA methylation is considered a major mechanism for silencing tumor suppressor genes in gastric cancer. We used CpG microarray and differential methylation hybridization strategies to identify potential tumor suppressor genes and recovered glutamate receptor, ionotropic, kainate 2 (GRIK2) as a novel epigenetic target in gastric cancer. Additional experiments showed that the promoter region of GRIK2 was hypermethylated in 3 of the 4 tested gastric cancer cell lines, and its expression was restored by treatment of cells with the DNA methylation inhibitor, 5'-aza-dC. In clinical samples, the GRIK2 promoter was differentially hypermethylated in tumor tissues compared with adjacent normal tissues (p < 0.001), and this methylation was inversely correlated with the expression level of GRIK2 mRNA (r = -0.44). Functional studies further showed that GRIK2-expressing gastric cancer cell lines showed decreased colony formation and cell migration. Taken together, these results suggest that GRIK2 may play a tumor-suppressor role in gastric cancer. Future studies are warranted to examine whether DNA hypermethylation of the GRIK2 promoter can be used as a potential tumor marker for gastric cancer.

Aberrant DNA methylation profile and frequent methylation of KLK10 and OXGR1 genes in hepatocellular carcinoma.

Investigating aberrant DNA methylation in the cancer genome may identify genes that play an important role in tumor progression. In this study, we combined differential methylation hybridization and a CpG microarray platform to characterize methylation profiles and identify novel candidate genes associated with hepatocellular carcinoma (HCC). The genomic DNA of 21 paired adjacent normal and HCC samples was used, and results were analyzed by hierarchical clustering. Twenty-seven hypermethylated candidates and 38 hypomethylated candidates were obtained. Six candidate genes from the hypermethylated group were validated by combined bisulfite restriction analysis; two genes, human kallikrein 10 gene (KLK10) and oxoglutarate (alpha-ketoglutarate) receptor 1 gene (OXGR1), were further analyzed by bisulfite sequencing. The DNA hypermethylation status of KLK10 and OXGR1 were subsequently examined in HCC cell lines and clinical samples using methylation-specific PCR. In 49 HCC samples, 46 (94%) showed that at least one of these two genes was highly methylated. Moreover, KLK10 and OXGR1 mRNA levels were inversely correlated (r = -0.435 and -0.497, P < 0.05) with DNA methylation as examined in paired adjacent normal and tumor samples. Statistical analyses further indicated that KLK10 hypermethylation was significantly associated with cirrhosis (P = 0.042) and HCV infection (P = 0.017) as well as inversely associated with HBV infection (P = 0.023). Furthermore, restoration of KLK10 and OXGR1 expression reduced the ability of anchorage-independent growth, and sensitized HCC cells to doxorubicin- or 5-fluorouracil-induced cytotoxicity. Our results suggest that the hypermethylated KLK10 and OXGR1 are frequent in HCC and may be useful as markers for clinical application.

Effects of Cd and Zn on oxygen consumption and ammonia excretion in sipuncula (Phascolosoma esculenta).

Physiological responses (oxygen consumption and ammonia excretion) of the sipuncula (Phascolosoma esculenta) exposed to four concentrations of Cd (0.45, 0.96, 2.04, and 4.46 mg L(-1)) and four concentrations of Zn (1.09, 2.34, 4.96, and 10.91 mg L(-1)) were monitored for 21 days, respectively. Oxygen consumption rates of sipuncula at all concentrations of Cd decreased from day 1 to day 6. At low concentrations of Cd (0.45 and 0.96 mg L(-1)), the oxygen consumption rate was promoted. Time and concentration were significant in affecting oxygen consumption rate, respectively. Oxygen consumption rate decreased significantly with time for Zn-exposed individuals and also decreased significantly with the interaction between the concentration of Cd and time for Cd-exposed individuals. Changes occurred in the ammonia excretion rates and O:N ratios with individual sipuncula experiencing different metal concentrations over time. Although low O:N ratios (<30) were obtained in most of the treatments, no predictable correlation was found between concentrations of metals and values of O:N obtained. The value of using O:N ratio as a stress index is questioned.

Pyrethroids as promising marine antifoulants: laboratory and field studies.

Due to the regulations and bans regarding the use of traditional toxic chemicals against marine fouling organisms and the practical impediments to the commercialization of natural product antifoulants, there is an urgent need for compounds that are antifouling-active, environmentally friendly, and have a potential for commercial application. In this study, a series of common, commercially available pyrethroid products, which are generally used as environmentally safe insecticides, was evaluated for antifouling activity in the laboratory using an anti-settlement test with cyprids of the barnacle Balanus albicostatus and also in a field experiment. Laboratory assay showed that all eleven pyrethroids (namely, rich d-trans-allethrin, Es-biothrin, rich d-prallethrin, S-prallethrin, tetramethrin, rich d-tetramethrin, phenothrin, cyphenothrin, permethrin, cypermethrin, and high active cypermethrin) were able to inhibit barnacle settlement (EC(50) range of 0.0316 to 87.00 microg/ml) without significant toxicity. Analysis of structure-activity relationships suggested that the cyano group at the alpha-carbon position had a significant influence on the expression of antifouling activity in pyrethroids. In the field, the antifouling activity of pyrethroids was further confirmed, with the most potent pyrethroids being cypermethrin and high active cypermethrin, which displayed efficiency comparable with that of tributyltin. In summary, our investigation indicated that these pyrethroids have a great and practical commercial potential as antifouling agents.

A risk assessment system for alien plant bio-invasion in Xiamen, China.

Bio-invasion has caused serious ecosystem damage and enormous economic losses in China, and it has been the greatest factor to island bio-diversity reduction. Xiamen, as an important seaport with a relatively high conservation value, is particularly vulnerable to bio-invasion for its typical island ecosystem as well as frequent human-made disturbance. As a result of field surveys, literature review, and consultation with experts, a list of 67 alien plants identified as major invaders (12 species) and emerging invaders (55 species) in Xiamen has been compiled. Based on the analysis of the current situation of bio-invasion in Xiamen, a risk assessment system for alien plant invasion has been designed using a ranking system and an analytic hierarchy process. The system consists of 17 secondary indices, grouped into 6 primary indices reflecting the different stages in the bio-invasion process: introduction, establishment, dispersion, current range, infestation, and artificial control. Biogeographical, ecological, and experience-linked aspects of the species as well as artificial disturbance were taken into account in the index selection and criterion development. The system was then validated (and worked well) using fifty well-known alien plant species as candidates. Appropriate recommendations are proposed to help local policy-makers prioritize their decisions on such alien plants.

[Distribution of Littoraia melanostoma Gray (Littorinidae) and Nerita lineata Gmelin (Neritadae) in rehabilitated mangroves].

An investigation was made in April and July 2005 on the abundance and biomass of Littoraia melanostoma ( Littorinidae) and Nerita lineata (Neritadae) in the rehabilitated mangrove forests with different mangrove species and stand ages at the Jiulongjiang Estuary of Fujian Province. The results showed that Nerita lineata was more abundant in mature stands, and had greater biomass and density in Kandelia candel stand than in Aegiceras corniculatum stand. A. corniculatum stand had greater density and biomass of L. melanostoma than K. candel stand, when the two stands had similar ages. In A. corniculatum stands, the biomass of L. melanostoma increased with the age of younger stands; while in K. candel stands, it decreased with the development of the forests. Different habitation patterns of the two snails in different mangrove stands indicated that N. lineate had a strong inhabitation preference for mature K. candel forest, while L. melanostoma was apt to inhabit in younger A. corniculatum forests.

[Energy characteristics of Casuarina equisetifolia ecosystem on coastal sand in Dongshan County, Fujian Province].

The study on the energy characteristics of Casurina equisetifolia community on red earth eolian sandy soil and homogeneous eolian sandy soil in Dongshan County of Fujian Province showed that the standing biomass and energy of Casurina equisetifolia community were 15 681.84 g x m(-2) and 317 795.31 kJ x m(-2) on red earth eolian sandy soil, and 5 129.87 g x m(-2) and 10 575.50 kJ x m(-2) on homogeneous eolian sandy soil, respectively. On homogeneous eolian sandy soil, the gross caloric value of the community ranged from 19.98 kJ x g(-1) to 21.39 kJ x g(-1), of which, dead branch was the highest while root was the lowest, and its percentage was 46.93% (truck) > 16.44%(root) > 13.92% (branch) > 12.28% (dead branch) > 5.87% (bark) > 3.90% (leaf) > 0.66% (fruit). The return amount of litter was 2061.77 kJ x m(-2) x yr(-1), and the net energy productivity was 12662.82 kJ x m(-2) x yr(-1). On red earth eolian sandy soil, the gross caloric value was 19.84 - 21.70 kJ x g(-1), among which, leaf was the highest while root was the lowest, and its percentage was 38.09% (truck) > 19.48% (branch) > 17.09% (root) > 16.86% (leaf) >6.83% (bark) > 0.88% (dead branch) > 0.77% (fruit). The returned amount of litter was 9070.47 kJ x m(-2) x yr(-1), and the net energy productivity was 31 298.70 kJ x m(-2) yr(-1). The standing biomass and energy of Casurina equisetifolia community were higher on red earth eolian sandy soil than on homogeneous eolian sandy soil, mainly because red earth eolian sandy soil had a thinner sandy layer (< 20 cm) and a stronger nutrient and water supplying ability.