Distribution of carbon, nitrogen and phosphorus in coastal wetland soil related land use in the Modern Yellow River Delta.

Junbao Yu,Guangxuan Han,Chao Zhan,Yunzhao Li,Yuqin Fu,Qinghui Xing,Xiaojing Chu,Di Zhou,Guangmei Wang,Qing Wang,Bo Guan

doi:10.1038/srep37940

Abstract

The delivery and distribution of nutrients in coastal wetland ecosystems is much related to the land use. The spatial variations of TOC, TN, NH4+-N, NO3−-N and TP and associated soil salinity with depth in 9 kinds land uses in coastal zone of the modern Yellow River Delta (YRD) was evaluated based on monitoring data in field from 2009 to 2015. The results showed that the average contents of soil TOC, TN, NO3−-N, NH4+-N and TP were 4.21 ± 2.40 g kg−1, 375.91 ± 213.44, 5.36 ± 9.59 and 7.20 ± 5.58 and 591.27 ± 91.16 mg kg−1, respectively. The high N and C contents were found in cropland in southern part and low values in natural wetland, while TP was relatively stable both in profiles and in different land uses. The land use, land formation age and salinity were important factors influencing distributions of TOC and N. Higher contents of TOC and N were observed in older formation age lands in whole study region, while the opposite regulation were found in new-born natural wetland, indicating that the anthropogenic activities could greatly alter the original distribution regulations of nutrients in coastal natural wetlands by changing the regional land use.

Highlights

The delivery and distribution of nutrients in coastal wetland ecosystems is much related to the land use
The natural wetland types in the modern Yellow River Delta (YRD) can be divided into degraded wetland (485 km2) which distributed in north part and new-born wetland (1 045 km2) which located in east part (Fig. 1)
The Landsat Thematic Mapper digital images with ground resolution of 30 meters of 2009 were used to study the lands use and land cover and variations in total organic carbon (TOC), total nitrogen (TN), NH4+-N, NO3−-N and total phosphorus (TP) content were evaluated in soil samples collected from 89 soil sampling sites of the modern YRD, eastern China, during 2009–2012 in this study

Summary

Introduction

The delivery and distribution of nutrients in coastal wetland ecosystems is much related to the land use. Higher contents of TOC and N were observed in older formation age lands in whole study region, while the opposite regulation were found in new-born natural wetland, indicating that the anthropogenic activities could greatly alter the original distribution regulations of nutrients in coastal natural wetlands by changing the regional land use. Whole ecosystem scale nutrients information regarding the biogeochemical processes of C, N and P responsible for regulating the spatial distribution related land use and salinity studies in the YRD coastal systems is still lacking. We report on nutrients of total organic carbon (TOC), total nitrogen (TN), ammonium (NH4+-N), Nitrate nitrogen (NO3−-N) and total phosphorus (TP) measured in soils at several coastal wetland sites in the whole modern YRD and assess the effects of land use classifications and soil salinity properties on nutrient distributions. The objectives of the present study were to determine (1) the spatial distribution of TOC, TN, NH4+-N, NO3−-N and TP related with land use; (2) the relations of soil nutrient distributions and anthropogenic activities and studied region formation period, and (3) the effects of soil salinity on nutrients in coastal region

Objectives

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Results

Conclusion