As a major component of urban ecological systems, the urban ecological space is an important carbon pool in the urban carbon circulation. Meanwhile, its special recreational function adds to the complexity of its carbon effects. According to the carbon process and effects of the urban ecological recreational system, the Source-Leakage-Sink-Order(SLSO) framework is proposed as the basis of the four subsystems of the system model. Consisting of 63 parameters, the system dynamics model of urban ecological recreational system is constructed by using VENSIM PLE. Then the urban ecological recreational system in Shanghai under different scenarios is simulated, and the carbon sources and sinks of the system as well as the process of carbon effects such as carbon footprints are analyzed and predicted. Research shows that due to the imbalance of the spatial pattern of ecological recreational space, the carbon sink effects of the system are quite limited. The human carbon source is the main contributor of the system’s carbon sources and the carbon footprint deficit is striking. The management ability of ecological recreational space influences the carbon sink potentials of the system. In addition,the maintenance mode of ecological green space plays a non-trivial role in the composition of carbon sources.
An imbedded integrating ecological entity(IIEE) was designed to combine landscaping, replenishing-water purifying and ecosystem maintaining simultaneously. With this IIEE, within 15 d experiment, simulated replenish water(SRW) with high(SRW-Ⅰ) or low(SRW-Ⅱ) nutrients concentration was well purified. Relative removal rates of CODCr, TP, TN, Chl-a and turbidity reached 84.87%, 84.05%, 94.76%, 188.17%, 110.93% when dealing SRW-Ⅰ, and 52.62%, 90.05%, 82.44%, 166.15%, 202.99%, respectively, when dealing SRW-Ⅱ. The well grew flora and fauna of IIEE benefit eco-maintaining and landscaping. Separately, the maximal root and stem length-increments of Cyperus alternifolius Linn. were 26.1 mm and 28.4 mm, while for Potamogeton crispus Linn. 18.3 mm and 25.7 mm. Mortality for both Bellamya aeruginosa and Misgurnus anguillicaudatus was both under 2.96%. The analysis of variance(ANOVA) indicated that most experimental indexes in each group performed more significantly better than those in their control. All results indicated that the IIEE is a promising technology for future urban waterscapes construction.
The remediation of Pb-contaminated port sediment by biosurfactant from a new isolated Bacillus sp.G1was studied.ThePb removal efficiencies were investigated under multi-levels of water-solid ratio,pH and ionic strength.Result showed thatexchangeable speciation of Pb could be removed by maximum removal capacity of76.8mg/g after leaching.The Langmuir isothermreflected the adsorption process best to fit the experimental adsorption equilibrium data.Fourier transform infrared spectra(FTIR)indicated that C=O and-CH3may be the functional groups.Scanning electron microscopy(SEM)analysis showed that thesurface of the port sediment became much smoother after adsorption interaction,which reflected that the complexation between Pbions and biosurfactant was more stable.The results indicated that the biosurfactant of Bacillus sp.G1could remove Pb effectivelyfrom the Pb-contaminated port sediment(PCPS)and suggested a novel method for PCPS remediation.
