Abstract
Agricultural reclamation in coastal zones is effective for mitigating population pressure on the food supply. Soil properties are important factors influencing crop production in reclaimed coastal lands. This study aims to investigate the impacts of time and land use trajectories on soil physicochemical properties after reclamation. We sampled soils in areas that were reclaimed in 1999, 1998, 1991, 1989, 1986, 1981, and 1979 and determined some soil physicochemical properties such as electrical conductivity with a 1:5 soil:water ratio (EC1:5), exchange sodium percentage (ESP), sodium adsorption ratio (SAR), pH, organic matter (OM), total nitrogen (TN), alkaline hydrolyzable nitrogen (AN), cation exchange capacity (CEC), total phosphorus (TP), available phosphorus (TP) and soil particle size ratio. We analyzed their correlation with land use and the time since reclamation using one-way analysis of variance (ANOVA) and principal component analysis (PCA). The results showed that soil physicochemical properties changed significantly after agricultural reclamation. Soil EC1:5, ESP, and SAR declined rapidly, and OM, TN, and AN increased rapidly during the 29 years after reclamation. The soil particle size ratio was not significantly correlated with reclamation time. The land-use trajectories identified after reclamation had obvious effects on soil physicochemical properties. Aquaculture ponds were superior to cultivated land in terms of decreasing soil salinity but were inferior in terms of soil nutrient accumulation. In the future, more attention should be given to the environmental effects of agricultural reclaimed soils.
Highlights
Due to industrialization and urbanization, conflicts related to human land use and the limited land resources in coastal zones have become increasingly prominent [1,2]
We found that the period of approximately 30 to 40 years since reclamation was the transition phase for soil, which is in agreement with many other studies [4,12,13,14,33]
The coastal reclaimed soils showed a prominent pattern of soil evolution during the period of approximately 30 years since reclamation
Summary
Due to industrialization and urbanization, conflicts related to human land use and the limited land resources in coastal zones have become increasingly prominent [1,2]. Coastal reclaimed lands have been developed mainly for agriculture, salt production, mariculture, port construction, and industrial uses [1,4]. The limited no-reclaimed land available, strict national reclamation control and ecological security might constrain such ambitions. These limitations can be found in other coastal parts of China such as the Yellow Sea region and the Pearl River Delta where economic development intensifies coastal reclamation while the loss of coastal wetlands challenges these activities. Land use and its environmental effects on reclaimed land are very important for coastal sustainability
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
