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The water of urban landscape park is often confronted with microalgal blooms due to its stagnancy. Bioremediation using the combined emergent and submerged plants to control the microalgae growth was investigated in the present study. Two water bodies (Bei and Xin) of Yuyuantan Park in Beijing were selected for the field experiments, and the other lakes with different vegetation of macrophytes were selected as the comparison. The concentrations of chlorophyll a (chl a), chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP), and water temperature and transparency were monitored before and after bioremediation from 2015 to 2017. Results showed that the effects of microalgal inhibition were more significant 2 years after bioremediation. Specifically, the chl a of Dong Lake without any vegetation of macrophytes was up to 65.1 μg/L in summer of 2017, while the Bei and Xin Lakes was only 6.2 and 11.3 μg/L, respectively. In addition, the water quality and transparency also improved, with water bodies being crystal clear. Submerged plants played major roles in microalgal control and water quality improvement, compared to the lakes with only emergent plants. The intensity of humic acid-like substances in three-dimensional fluorescent spectra was stronger for the lakes with submerged plants. [ABSTRACT FROM AUTHOR]

[Display omitted] • A framework for assessing comprehensive RECC is developed. • The system dynamic model is used to simulate relations in human-environment system. • Water is the main constraining factor to urban development in the study region. • "Business-as-usual" development mode is recommended for future development. Resources and environment carrying capacity (RECC) is an important concept for regional and urban sustainable development. This study constructs a comprehensive RECC indicator and a system dynamics (SD) model to simulate its historical conditions and future scenarios, stressing the nexus between the socio-economic and eco-environmental factors. This methodology is applied to Beijing–Tianjin–Hebei urban agglomeration (BTH) for the period of 2000–2030. The results show that, in the business-as-usual scenario, BTH's RECC will present an "S" curve and increase from 100.26 million in 2000 to 129.65 million in 2030. Although it is greatly improved, the risk of population overload will increase, especially in Beijing, Baoding and Langfang city. Moreover, water resources carrying capacity will be the key constraining factor of RECC for BTH and its most cities. Compared with the economic-oriented and ecological-oriented development mode, to maintain the "business-as-usual" development mode is recommended for the whole BTH. However, the south-central cities should take the ecological-oriented development mode to overcome population overload. This research presents a framework to assess RECC under different scenarios for urban agglomeration. The results might provide an important guidance for sustainable urban planning and coupled human-environment system analysis. [ABSTRACT FROM AUTHOR]