Expansion and Management Implications of Invasive Alien Spartina alterniflora in Yancheng Salt Marshes, China

Improved understanding of the spatial dynamics of invasive plant species is critical for effective land management and control of future invasion. The Yancheng National Nature Reserve (YNNR), an internationally important wetland, has the largest distribution of alien Spartina alterniflora in China. This alien plant was intentionally introduced for erosion prevention and dike protection in China. However, it became an aggressive competitor with native salt marsh plants in the coastal regions in China. High resolution imagery, SPOT-5, was used to map plant communities including invasive species in the south core zone of YNNR with the natural ecosystem of salt marshes in 2003, 2005 and 2008. The fuzzy set assessment method significantly improved the classification accuracies over the conventional error matrix, i.e., from 73.8%, 73.5% and 81.4% to 91.5%, 91.6% and 93.4% in 2003, 2005 and 2008, respectively. It shows a great potential for mapping invasive plant species. Phragmites australis and S. alterniflora were the most accurately mapped classes, and sparse and dense Suaeda glauca were the least accurately mapped. From 2003 to 2008, S. alterniflora increased 28.8% from 1664.1 to 2142.6 ha in area size, and more than 2.5 times from 742 to 2608 patches. The highest increase in patch number occurred within the interval between 2001 and 3000 m from the eastern baseline. This increase was dominated by small patches with area less than 200 m2. During the study period, the mean spread width was 405 ± 80.7 m in the original large patch of area over 200 ha. The eastward/seaward spread was distinctively larger than the westward/landward. The results enhance the understanding of alien plant’s invasion patterns and help improve conservation efforts.

Recreational Attractiveness of Urban Parks and Implications for Their Management:A Case Study in Changchun,China

Urban parks are an important part of urban ecosystems and also provide recreational services for urban residents.However,it is still unclear how the recreational attractiveness of urban parks can be evaluated.In this study,12 typical parks in Changchun,China were selected for evaluation of their recreational attractiveness.We built a recreational attractiveness evaluation system based on the analytical hierarchy process(AHP)to produce a composite evaluation index.This method included:1)the landscape quality of the parks;2)the recreational facilities;3)the conditions of the area;and 4)the accessibility of the parks.Our results showed that Nanhu Park,Children’s Park,Shengli Park,and Jingyuetan Forest Park had high recreational attractiveness,whereas Linyuan Park had the lowest attractiveness among the 12 parks.These results agreed with the information obtained from a field survey of the actual recreational and revisit rates,which showed that the evaluation index is reliable.Correlation analysis showed that the landscape quality and recreational facilities of parks had a direct effect on their recreational attractiveness.A negative correlation was found between the accessibility of a park and its recreational attractiveness.We conclude that if the scenery and facilities are not as good as a visitor expects,then they may choose to visit a different park,even if it takes a longer time to reach.

Common eye drops and their implications for p H measurements in the management of chemical eye injuries

Dear Sir,Eye drops(single use)commonly used in clinics do have varying pH values.The use of such drops in the initial management of chemical eye injury may influence the accuracy of pH measurement of the eye,and subsequently influence its management.Chemical eye injury is an ophthalmic emergency,which may be caused by exposure to an acidic(pH【4)or an alkali(pH】10)solution to the eye.Rinsing the eye decreases the concentration of these solutions on ocular surface.The initial management would be copious irrigation with clean or sterile water or Ringer’s solution(pH 7.3-7.4)or its equivalent,of a

Managing Variation and Resolving the Trade-off Implications of Global Supply

The reduction of wasteful variation within the supp ly chain is naturally suited to high and stable volumes, as epitomised in the lean practices of the automotive industry. However, with the growth of innovative pr oducts, typically characterised by lower volumes and uncertain demand, it is als o important to develop strategies to effectively manage the externally imposed v ariation resulting from volatile market demand. Such strategies often come under the banner of quick response or agile supply. System variation is the common denominator, for whereas lean strategies emphasis e the need for stability and the reduction of wasteful supply chain variation, a gile emphasises the need to respond to externally imposed demand variation. Simi larly, lean supply is closely associated with level scheduling and investing in inventory to decouple demand variation from the supply chain, whereas, agile sup ply is associated with investing in responsive capacity as inventory requirement s cannot be effectively predicted. This distinction between lean and agile supply, highlights a trade-off between investing in responsive capacity and decoupling inventory, which is closely related to the conflicting manufacturing tasks of fast response and low cost. The implications of this conflict have been more widely felt in recent years, as companies have opted to outsource manufacture to low cost overseas suppliers. T he rationale is to reduce manufacturing costs, but the trade-off is a dramatic loss of responsive capacity with higher dependency on decoupling inventory. As with lean and agile supply, the trade-off implications of such choices need to be acknowledged, conceptually understood and then separate out or otherwise r esolved. This paper introduces the business need before exploring the significance of var iation and the concept of managing variation in a delivery system using responsi ve capacity and decoupling inventory. These concepts will then be used to unpack the lean and agile paradigms before applying the thinking to a more detailed in dustrial case concerning offshore supply decisions. The paper concludes with som e reflections.

Mitochondrial Haplotypes suggest Genetic Component for Habitat Preference in Blue Crabs

Atlantic blue crabs(Callinectes sapidus)are ecologically and commercially fundamental.Life stages are punctuated with migration.Adults and juveniles live in estuaries and sounds.Larval stages develop in the coastal ocean.Juvenile and adult crabs occupy habitats from high salinities to fresh water.We determined whether maturing juvenile and adult blue crab habitat use is reflected in mitochondrial cytochrome oxidase 1 haplotypes.High salinity crabs had lower haplotype diversity(0.7260±.03900)compared to spawning crabs(0.9841±.00021)and low salinity crabs(0.94154±.00118).Significant pairwise differences in haplotypes were found between high salinity and spawning crabs(Nm=0.26018,p<0.001),and between high salinity and low salinity crabs(Nm=0.19482,p<0.001)indicating a lack of gene flow.Crabs from high salinity had highly significant genetic differentiation compared to spawning crabs(Fst=0.11830,p<0.001)and low salinity crabs(Fst=0.09689,p<0.001).Results support the hypothesis that genetics influence habitat selection.Crab larvae mix in the coastal ocean but occupy specific habitats upon return to sounds and estuaries.These findings have implications for the management of fisheries.