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The implementation of an urban growth boundary (UGB) can effectively control urban sprawl and promote efficient land use, which is crucial for future urban development. However, most of existing studies overlook the reuse of existing idle and inefficient land within the city in the delineation of UGBs. With China's urban construction shifting from incremental development to stock development, this study focuses on Wuhan and presents a set of technical approaches for delineating UGBs with a stock development orientation. First, a built-up area composite index (POI&ISA) is constructed based on point of interest (POI) kernel density analysis and impervious surface index extraction to evaluate constructive levels in 2010 and 2020 and identify the urban vitality zone. Then, we combine the current land use status and control policies to divide the urban spatial development potential into five categories: urban vitality land, urban non-vitality land, other vitality land, other non-vitality land, and restricted development land. Finally, the PLUS model is applied in the analysis of the driving forces of land use change in Wuhan, simulating the UGBs in three stages of incremental development (2020–2030), incremental and stock development (2030–2040), and stock development (2040–2050). Finally, the PLUS model simulation projects the UGB areas to be 436.436 km2, 474.617 km2, and 520.396 km2 for the years 2030, 2040, and 2050, respectively. The predicted timespan of urban development extends up to 30 years, serving as a reliable reference for Wuhan's long-term and near-term planning. [ABSTRACT FROM AUTHOR]

The implementation of an urban growth boundary (UGB) can effectively control urban sprawl and promote efficient land use, which is crucial for future urban development. However, most of existing studies overlook the reuse of existing idle and inefficient land within the city in the delineation of UGBs. With China’s urban construction shifting from incremental development to stock development, this study focuses on Wuhan and presents a set of technical approaches for delineating UGBs with a stock development orientation. First, a built-up area composite index (POI&ISA) is constructed based on point of interest (POI) kernel density analysis and impervious surface index extraction to evaluate constructive levels in 2010 and 2020 and identify the urban vitality zone. Then, we combine the current land use status and control policies to divide the urban spatial development potential into five categories: urban vitality land, urban non-vitality land, other vitality land, other non-vitality land, and restricted development land. Finally, the PLUS model is applied in the analysis of the driving forces of land use change in Wuhan, simulating the UGBs in three stages of incremental development (2020–2030), incremental and stock development (2030–2040), and stock development (2040–2050). Finally, the PLUS model simulation projects the UGB areas to be 436.436 km2, 474.617 km2, and 520.396 km2 for the years 2030, 2040, and 2050, respectively. The predicted timespan of urban development extends up to 30 years, serving as a reliable reference for Wuhan’s long-term and near-term planning.

The brown shrimp, Crangon crangon, is the most important target of the coastal crustacean fisheries in the German Bight. In order to evaluate the relation between the abundance of ovigerous females and larvae in spring and the recruitment success in autumn, we first analysed the seasonal appearance of ovigerous females and larvae from weekly samples throughout 2012. The spawning season in the German Bight extends over several months comprising multiple unsynchronized spawning events. The minimum shares of ovigerous females appeared in early autumn, and the highest shares in late winter bearing mostly early egg stages. We defined the putative start of the reproductive cycle for November when the frequency of ovigerous females started to increase. There was no distinct separation between winter and summer eggs, but a continuous transition between large eggs spawned in winter (the early spawning season) and batches of smaller eggs in spring and summer. Larval densities peaked in April/May. Consequently, regular annual larval surveys from 2013 to 2016 were scheduled for April/May and extended to six transects covering the inner German Bight. Ovigerous females were most abundant in shallow waters above the 20‐m isobaths, which also explained regional differences in abundance between the regions off North Frisia and East Frisia. No relation was obvious between the number of larvae in spring and recruited stock in autumn. Due to the short lifespan of C. crangon, the combination of various abiotic factors and predator presence seems to be the principal parameters controlling stock size. [ABSTRACT FROM AUTHOR]

Eero, M., Köster, F. W., Plikshs, M., and Thurow, F. 2007. Eastern Baltic cod (Gadus morhua callarias) stock dynamics: extending the analytical assessment back to the mid-1940s. – ICES Journal of Marine Science, 64: 1257–1271. The status of the eastern Baltic cod (Gadus morhua callarias) stock has been assessed annually by ICES since 1966. To understand better the causes of stock fluctuations and to evaluate human impact on the stock relative to natural variability, longer time-series than currently available are needed. To achieve this, data back to the mid-1940s were compiled to extend the analytical assessment. Estimates are provided of stock development and its exploitation for a 20-year period before the start of the current assessment. The quality of the data and the credibility of the historical estimates are discussed. Considerable fluctuations in cod biomass and recruitment in the pre-assessment years were identified. Stock size was estimated to be relatively low after the Second World War, then increased during the first half of the 1950s, but did not reach the high levels of abundance subsequently observed in the early 1980s, and then declined towards the mid-1960s. Fishing mortality was low after the Second World War but increased rapidly in the second half of the 1950s, reaching the high levels observed since the 1980s. [ABSTRACT FROM AUTHOR]

Eero, M., Köster, F. W., Plikshs, M., and Thurow, F. 2007. Eastern Baltic cod (Gadus morhua callarias) stock dynamics: extending the analytical assessment back to the mid-1940s. – ICES Journal of Marine Science, 64: 1257–1271. The status of the eastern Baltic cod (Gadus morhua callarias) stock has been assessed annually by ICES since 1966. To understand better the causes of stock fluctuations and to evaluate human impact on the stock relative to natural variability, longer time-series than currently available are needed. To achieve this, data back to the mid-1940s were compiled to extend the analytical assessment. Estimates are provided of stock development and its exploitation for a 20-year period before the start of the current assessment. The quality of the data and the credibility of the historical estimates are discussed. Considerable fluctuations in cod biomass and recruitment in the pre-assessment years were identified. Stock size was estimated to be relatively low after the Second World War, then increased during the first half of the 1950s, but did not reach the high levels of abundance subsequently observed in the early 1980s, and then declined towards the mid-1960s. Fishing mortality was low after the Second World War but increased rapidly in the second half of the 1950s, reaching the high levels observed since the 1980s. [ABSTRACT FROM PUBLISHER]

The brackish water Baltic Sea is strongly influenced by irregular saline water inflows. Fewer inflow events since the 1980s have resulted in a decrease in salinity, and will according to predicted climate change continue to decrease. The newly described Baltic flounder Platichthys solemdali has adapted to reproduction at low salinity conditions since it colonized the Baltic Sea 7000 years BP; in the area studied (ICES SD 3d 28.2) spawning occurs at 3–20 m depth at ca 7 psu. Here we monitored variability in year-class strength as newly settled 0-gr fish in three coastal nursery areas, and compared obtained recruitment indices with prevailing temperature and salinity conditions. 0-gr abundance indices varied considerably between years, from 1 to 90, 10–296 and 17–86 at the respective sampling site, and showed strong accordance with the age structure of the adult stock. Variability in temperature showed no effect, but stronger and weaker year-classes respectively were related to variability in salinity in the range 6.6–7.1 psu with stronger year-classes at >6.8 psu. This coincides with variability in spermatozoa motility, fertilization rates and early egg development at different salinities and suggests that the year-class strength may be set already at the egg stage. Thus, only small changes in salinity at spawning may affect reproductive success and ultimately stock development. The potential effects on stock abundance and distribution facing climate change call for changes in future fishing patterns as well as adaptations in management to prevent stock collapse. • High variability in 0-gr abundance at settlement in nurseries. • High agreement between 0-gr abundance and age structure in the adult stock. • Strong and weak year-classes related to variability in salinity. • Recruitment coincides with variability in fertilization/egg survival at different salinities. • Stock development is governed mainly by variability in salinity. • Decrease in salinity due to climate change call for precaution in management. [ABSTRACT FROM AUTHOR]