Late Devonian (Frasnian) phyllopod and phyllocarid crustacean shields from Belgium reinterpreted as ammonoid anaptychi

The taxonomic affinities of fossils from the Frasnian succession of Belgium previously described as phyllopod and phyllocarid crustacean shields are discussed. The rediscovery of the holotype of Ellipsocaris dewalquei, the type species of the genus Ellipsocaris Woodward in Dewalque, 1882, allows to end the discussion on the taxonomic assignation of the genus Ellipsocaris. It is removed from the phyllopod crustaceans as interpreted originally and considered here as an ammonoid anaptychus. Furthermore, it is considered to be a junior synonym of the genus Sidetes Giebel, 1847. Similarly, Van Straelen’s (1933) lower to middle Frasnian record Spathiocaris chagrinensis Ruedemann, 1916, is also an ammonoid anaptychus. Although ammonoids can be relatively frequent in some Frasnian horizons of Belgium, anaptychi remain particularly scarce and the attribution to the present material to peculiar ammonoid species is not possible.     

Target loads of atmospheric sulfur deposition for the protection and recovery of acid-sensitive streams in the Southern Blue Ridge Province

An important tool in the evaluation of acidification damage to aquatic and terrestrial ecosystems is the critical load (CL), which represents the steady-state level of acidic deposition below which ecological damage would not be expected to occur, according to current scientific understanding. A deposition load intended to be protective of a specified resource condition at a particular point in time is generally called a target load (TL). The CL or TL for protection of aquatic biota is generally based on maintaining surface water acid neutralizing capacity (ANC) at an acceptable level. This study included calibration and application of the watershed model MAGIC (Model of Acidification of Groundwater in Catchments) to estimate the target sulfur (S) deposition load for the protection of aquatic resources at several future points in time in 66 generally acid-sensitive watersheds in the southern Blue Ridge province of North Carolina and two adjoining states. Potential future change in nitrogen leaching is not considered. Estimated TLs for S deposition ranged from zero (ecological objective not attainable by the specified point in time) to values many times greater than current S deposition depending on the selected site, ANC endpoint, and evaluation year. For some sites, one or more of the selected target ANC critical levels (0, 20, 50, 100μeq/L) could not be achieved by the year 2100 even if S deposition was reduced to zero and maintained at that level throughout the simulation. Many of these highly sensitive streams were simulated by the model to have had preindustrial ANC below some of these target values. For other sites, the watershed soils contained sufficiently large buffering capacity that even very high sustained levels of atmospheric S deposition would not reduce stream ANC below common damage thresholds.     

能源服务公司(ESCO)在中东欧的投资

能源服务公司(ESCO)使消费者能够用节能得到的未来现金流进行投资,使他们的设施升级并减少能源成本.ESCO使用了一种叫做"履约合同”的项目融资方法:保证鉴别设施节能的机会;在对消费者没有初始成本的条件下测量成本的节约;以及节约的能源用来支付初始的投资在北美和西欧ESC0产业的进展给中欧和东欧上了好几课     

Spatial-Scale Effects on Relative Importance of Physical Habitat Predictors of Stream Health

A common theme in recent landscape studies is the comparison of riparian and watershed land use as predictors of stream health. The objective of this study was to compare the performance of reach-scale habitat and remotely assessed watershed-scale habitat as predictors of stream health over varying spatial extents. Stream health was measured with scores on a fish index of biotic integrity (IBI) using data from 95 stream reaches in the Eastern Corn Belt Plain (ECBP) ecoregion of Indiana. Watersheds hierarchically nested within the ecoregion were used to regroup sampling locations to represent varying spatial extents. Reach habitat was represented by metrics of a qualitative habitat evaluation index, whereas watershed variables were represented by riparian forest, geomorphology, and hydrologic indices. The importance of reach- versus watershed-scale variables was measured by multiple regression model adjusted-R² and best subset comparisons in the general linear statistical framework. Watershed models had adjusted-R² ranging from 0.25 to 0.93 and reach models had adjusted-R² ranging from 0.09 to 0.86. Better-fitting models were associated with smaller spatial extents. Watershed models explained about 15% more variation in IBI scores than reach models on average. Variety of surficial geology contributed to decline in model predictive power. Results should be interpreted bearing in mind that reach habitat was qualitatively measured and only fish assemblages were used to measure stream health. Riparian forest and length-slope (LS) factor were the most important watershed-scale variables and mostly positively correlated with IBI scores, whereas substrate and riffle-pool quality were the important reach-scale variables in the ECBP.