Status of Mysis diluviana in Lake Ontario in 2013: Lower abundance but higher fecundity than in the 1990s

Mysis diluviana is a major component of prey fish diets in the Great Lakes, so annual production of M. diluviana is important for understanding and modeling energy flow through Great Lakes food webs. However, only three lake-wide measurements of M. diluviana annual production in Lake Ontario are currently available (1971, 1990, 1995). During 2013, lake-wide coverage of Lake Ontario was achieved during four periods from April to November. Annual mean density and biomass of M. diluviana in 2013 were 99?#/m² (SE: 8) and 318?mg?dw/m² (SE: 28) – approximately half of values observed in 1990s. M. diluviana comprised 13–30% of offshore zooplankton biomass in each period. Reproduction peaked in fall, with mean brood size of 32 embryos (range: 11–49), at least 10% larger than in 1990s. Generation time was two years from embryo to initial reproduction. Growth rates were 0.052?mm/d for the age-0 cohort and 0.027?mm/d for the age-1 cohort. Age-0 growth rate was significantly higher than in 1980s–90s (0.035?mm/d). Annual production in 2013 was 0.85?g?dw/m²/yr (SE: 0.03) which was 30–40% of values observed in 1990 and 1995 (2.23 and 2.53?g/m²/yr). Annual production to biomass ratio (P/B) in 2013 was 2.65?/yr which was 80–85% of values observed in 1990 and 1995 (3.24 and 3.11?/yr), but this difference was not statistically significant. Our results suggest that changes in annual production over time can be estimated using changes in biomass over time and a mean P/B ratio.     

天然植物提炼

从2007年年底开始,就已经能看出visvim在08年的新动向了,中村世纪摆明了要以最高级的材质打造出一系列以环保为基础的产品,不论是物料及设计构造均达到极高的水准。先期发售的是FBT BEAR FOOT-FOLK,最大的特点是采用薄底设计。而一向都是visvim鞋款中舒适度数一数二的FBT本次更将其全面包装,鞋面上居然穿上了民族风的珠子,打造出最高水准的FBT鞋款。随后发售的鞋款也是FOLK series的成员。与前面提到的的BEARFOOT相似,     

NIKE JP TANABATA MATSURI PACK 七夕

农历七月,不要以为就只有我国才知道牛郎织女;其实,远在东瀛的日本也有个同名同义的七夕节,即每年农历七月七日织女（Orihime）与牛郎（Hikoboshi）相会的日子。每到日本的七夕节,传统就是穿上和服成群结队的走上大街,很多人手里都会提着一个红灯笼,     

皮质托盘 BAPE Leather Tray

BAPE最新推出的皮制托盘可以说是BAPE近来的创意之作,可以让大家摆放杂物、锁匙等零碎物品,是非常实用的家居装饰物。米色皮革中心印有猿人图案,所采用的边角纽扣的组合设计十分方便存放,而且分别有大小两种规格,不过千万不要拿它当烟灰缸,否则烟灰会将皮革烧穿。而服饰方面,BAPE将过往一系列成功的图案设计再度逐一呈现在大家眼前,print tee有鲨鱼、老虎和熊猫头图案,zip—up也有猿猴脸迷彩、虎纹迷彩等等,长久以来喜欢BAPE的朋友可以借此“温故”。而新推出的牛仔裤作品主打工装风格,这也与今年秋冬季很多牛仔品牌的主打路线吻合,裤子采用painter denim的剪裁,其中hickory的竖条纹牛仔裤更加是工装“范儿’的标准装备。     

Early observations on an emerging Great Lakes invader Hemimysis anomala in Lake Ontario

Hemimysis anomala, a Ponto-Caspian littoral mysid, is an emerging Great Lakes invader that was discovered in Lakes Michigan and Ontario in 2006. Similar to the native mysid Mysis diluviana, Hemimysis exhibits a diel vertical migration pattern but generally inhabits shallower and warmer waters than M. diluviana. Because basic information on the distribution, habitat use, and biology of Hemimysis in the Great Lakes is scarce, the potential for food web disruption by Hemimysis cannot easily be predicted. Preliminary observations indicate widespread invasion of Hemimysis in Lake Ontario. In this study, we confirm the presence of Hemimysis at sites spanning the northern and southern shores of Lake Ontario and the presence of the individuals during winter months. In one horizontal tow in November 2007, over 26,000 individuals were collected with a length range of 4.4 to 9.0 mm and an average caloric density of 611 cal/g wet weight. The most effective methods for sampling Hemimysis were horizontal tows with either a zooplankton net in the water column or a benthic sled near the lake bottom. Although more quantitative data on the life history and distribution of this species is necessary, our preliminary observations support the prediction that the potential for Hemimysis to impact the nearshore food web in Lake Ontario appears high.     

Book reviews

BT Environment City Bulletin: The Big Picture - all eight topics under one roof Edited by C. Wood, 1994, Lincoln, The Wildlife Trusts, 110pp., £19.00 for local authorities, £14.00 for local businesses, £9.00 for voluntary groups.

Theme Parks, Leisure Centres, Zoos and Aquaria Anthony and Patricia Wylson, 1994, Harlow, Longman, 183pp. ISBN 0 582 09928 5, hb £60.00

The Picturesque Landscape: Visions of Georgian Herefordshire Edited by Stephen Daniels and Charles Watkins, 1994, Department of Geography, University of Nottingham, 100pp. ISBN 0 85358 033 2, £7.50

The Countryside Ideal: Anglo-American Images of Landscape Michael Bunce, 1994, London, Routledge, 232pp. ISBN 0 415 10435 1

Ordering Space: Types in Architecture and Design Karen A Frank and Lynda H Schneekloth (eds.), 1994, New York, Van Norstrand Reinhold, 383pp ISBN 0 442 01233 0, pb £34.50     

REMOVAL OF RESIDUAL CHLORINE FROM INDIANA 5 COAL BY SUPERCRITICAL CARBON DIOXIDE EXTRACTION

The perchloroethylene coal desulfurization process has unique advantages as a precombustion coal cleaning process, that include high cleaning efficiencies, mild process conditions, minimal output of undesirable byproducts, and cost effectiveness. However, the use of perchloroethylene in the process renders an important process engineering problem of complete recovery and reuse of perchloroethylene. thus requiring a “zero discharge” condition of the solvent. Therefore, the treated coal must be stripped of any residual perchloroethylene. Carbon dioxide (CO₂) in its supercritical state has been investigated for its ability to remove chlorine from Indiana 5 coal, that has been desulfurized by the perchloroethylene (PCE) process. The reduction of CI contenttffrom a PCE treated and filtered coal has been as high as 78% The exprements have been carried out. following a statistical experimental design and the discerning characteristics of the process been identified. The solvent density and extraction conditions can be tailored in such a way as to optimally remove CI from the coal without any detrimental effects on the coal matrix. The supercritical CO₂ extraction process can be successfully implemented to the PCE coal cleaning process by replacing energy intensive steps of steam stripping and vacuum dying     

An Initial Inventory and Indexation of Groundwater Mega-Depletion Cases

The state of groundwater systems worldwide is presently not well defined, and in particular there is little context for agencies responsible for managing water resources to evaluate occurrences of groundwater depletion against other cases globally. In this study, an initial inventory of groundwater depletion problems is compiled and ranked to identify the world’s most critical cases, i.e. situations of groundwater mega-depletion. The ranking is based on an indexed approach that considers overdraft, drawdown and subsidence, plus the importance of the resources in terms of population-dependency and rates of extraction. The five most highly ranked depleted aquifers of the world include the shallow aquifers of the Hai River Plain (China), the Altiplano region (Spain), the Mexico Basin (Mexico), the Huang River basin (China) and the California Central Valley (USA). An abridged account of modelling to assess drawdown is described for the Hai River Plain, revealing that despite recharge in the order of 13,000 GL/yr, an overdraft of about 8,000 GL/yr is occurring to support the vast population of the region. This has led to up to 100 m of drawdown in places and reports of subsidence of several metres. The Hai River situation demonstrates that falling water levels may not act to alleviate pumping stresses; a symptom of unchecked extraction and an exemplary illustration of the tragedy of the commons. The causal factors leading to mega-depletion are varying across the globe and each mega-depletion case contains unique elements, although population appears to be an important factor.     

Evolving International Collaborative Arrangements for Water Supply and Sanitation

ABSTRACT

This article addresses the problem of identifying annual operation, maintenance, and replacement (OM&;R) expenditures needed to maintain performance of the water delivery system in Egypt. The deliver system, which includes the High Aswan Dam (HAD), large irrigation structures. pump stations, ond thousands of canals and drains, is described. Procedures for estimating these OM&;R costs and assessing system benefits in the various use sectors are presented. The article also explains the development and application of a cost allocation model to estimate the share of the various use sectors from the system cost.     

Multi‐objective risk assessment of freshwater inflow on ecosystem sustainability in San Antonio bay,Texas

Abstract:

San Antonio Bay is located on the coast of Texas between Galveston Bay and Corpus Christi Bay and is the primary bay in the Guadalupe Estuary. Three rivers feed San Antonio Bay from two river basins, including the Blanco and Guadalupe Rivers in the Guadalupe River Basin and the San Antonio River in the San Antonio River Basin. The Canyon Reservoir regulates the flow of fresh water in the middle and lower reaches of the Guadalupe River. These inflows are a primary regulator of salinity and, thus, the productivity of commercially important estuarine species. Increasing demand for water has prompted plans for an increased diversion of 49.3 million m³ (40,000 acre‐feet) from the reservoir. An additional amount of 61.6 million m³ (50,000 acre‐feet) from the mouth of the river is to be pumped back to San Antonio to relieve over‐pumping of the Edwards Aquifer. Because the Guadalupe River Basin contributes 58.1 percent of the freshwater inflow to the estuary, it is not known what the impact of these actions will have on the ecological integrity of the San Antonio Bay. Water resource management in the San Antonio Basin consists of decision making under risk and uncertainty related to randomness in the critical parameters such as the salinity in the bay, biological productivity, and total flow into the bay. The aim of this study is to investigate the trade‐offs between the competing objectives of maximizing biological productivity in the bay and minimizing flow using Stochastic Compromise Programming (SCP). The SCP model solves a multi‐objective function subject to constraints that must be maintained at three different prescribed levels of probability providing a global set of solutions for the water resource management problem under input uncertainty. The SCP model provides information on the trade‐offs among the objective function value, tolerance values of the constraint at the prescribed levels of probability, which could be valuable to policy makers in risk assessment. Solutions were found using three distance functions. Model outputs may suggest the minimum amount of freshwater needed to maximize biological productivity of the bay at specified risk level for assessing the impact of upcoming diversion program. Results indicate that current flows in the Guadalupe River are of sufficient volume to satisfy harvest requirements.