永康市副中心城镇绿色空间系统规划探索

城市绿色空间系统规划是城市规划的重要方面,也与城市形象息息相关。文章以浙江省永康市副中心城镇为例,探讨城镇密集地区绿色空间系统规划的内容及方法,主要包括城镇污染综合防治、总体布局及景观规划三个方面的内容。     

长三角区域经济社会发展的未来机遇和挑战

区域经济一体化是走向全球经济一体化的一个台阶和现阶段的较优途径;也是国际和地区经济社会发展中竞争与合作的重要表现形式。     

Distribution of the Amphipod Diporeia in Lake Superior: The Ring of Fire

Diporeia, formerly the dominant benthic macroinvertebrate in the Great Lakes, remains a keystone species in Lake Superior. Little is known, however, about fine scale amphipod distributions, especially as influenced by the production, transport and transformation of energy resources. Here, we document the distribution and abundance of Diporeia along 19 transects around the lake's perimeter. Regions of elevated density, averaging 958 ± 408 Diporeia/m² (mean ± S.D.) were observed along all transects, typically within slope habitat (depth of 30–125 m). Waters shoreward (shelf habitat, < 30 m) and lakeward (profundal habitat, > 125 m) of these regions supported significantly lower densities, averaging 239 ± 178/m² and 106 ± 59/m², respectively. Amphipods within regions of elevated density, termed here the Ring of Fire, account for two-thirds of the lakewide population while occupying only one-quarter of the benthic habitat. The Ring of Fire, observed lakewide as a band averaging 14.2 ± 9.4 km in width, is characterized as a region of transitional sediment deposition with gentle slope, proximate to nearshore locations of elevated primary production. Within the Ring of Fire exceptionally high densities are found in the south central region, where the Keweenaw Current and slope bathymetries serve to funnel production from adjoining regions of high production. Density measurements for the 173 stations sampled here are used to estimate lakewide Diporeia standing stock (22.5–37.7 trillion individuals, 4.4–7.4 Gg dry weight, 2.1–3.5 Gg C), individual and biomass density (274–460/m², 0.05–0.09 g DW/m², 0.03–0.04 gC/m²) and areal (0.02–0.03 g C/m²/yr) and total (1.6–2.6 Gg C/yr) production.     

International competitiveness,job creation and job destruction—An establishment-level study of German job flows

This study investigates the impact of international competitiveness on net employment, job creation, job destruction, and gross job flows for a representative sample of German establishments from 1993 to 2005. We find a statistically significant but economically small effect of real exchange rate shocks on employment, comparable to the one found in studies for the United States. However, contrary to the United States, the employment adjustment (among surviving firms) operates mainly through the job creation rather than the job destruction rate. Job destruction occurs essentially through discrete events such as restructuring, outsourcing and bankruptcy. We suggest that these findings are consistent with a highly regulated labor market, in which smooth adjustment is costly and possibly delayed.