Spatial variability of soil salinity in Bohai Sea coastal wetlands, China: Partition into four management zones

Abstract

Soil salinization constitutes an environmental hazard worldwide. The Bohai Sea coastal wetland area is experiencing dramatic soil salinization, which is affecting its economic development. This study focused on the spatial variation and distribution characteristics of soil salinity in this area using geostatistical analysis combined with the kriging interpolation method, based on a large-scale field investigation and layered soil sampling (0-30, 30-60 and 60 -100 cm). The results revealed that soil salinity in these layers demonstrated strong variability, obvious spatial structure characteristics and strong spatial autocorrelation. Soil salinity displayed a significant zonal distribution, gradually decreasing with increasing distance from the coastline. Apart from the northern part of the study area, which appeared to be not affected by soil salinization, there were varying degrees of soil salinization in nearly 70% of the total area. With increasing soil depth, the areas of non-salinized and mild salinized soil gradually decreased, while those of moderate salinized and strong salinized soils increased. The area of saline soil first decreased and then increased. The study area could be divided into four management zones according to soil salinities in the top 1-m soil body, and utilization measures, adapted to local conditions, were proposed for each zone. The results of our study present an important theoretical basis for the improvement of saline soils, for wetland re-vegetation and for the sustainable utilization of soil resources in the Bohai Sea coastal wetland.

Characteristics and Spatial Variability of Saline-Alkaline Soil Degradation in the Typical Yellow River Delta Area of Kenli County, China

“…The Yellow River Delta is the concentrated saline coastal area of China and the characteristics and spatial variability of saline soil salinity has also been concerned about by the growing number of scholars [13] [14]. For example, Fan Xiaomei discussed the severity, classification and characteristics of soil salinization, described the occurring environment and influencing factors of saline soils of Yellow River Delta based on field survey and soil sampling data [15]; Yao Rongjiang used statistics and geo-statistics methods to measure and analyze spatial variability of soil salinity of different soil layers and made their spatial distribution maps [16].…”

Soil enzymes as indicators of saline soil fertility under various soil amendments

“…Coastal areas play an important role in the global system. However, these areas are so vulnerable to climatic changes because of poor drainage system and the intrusion of seawater (Datta et al, 2013;Lv et al, 2013). Due to periodic tidal activity, the salinity changes seasonally (Shi et al, 2005;Sun et al, 2012) which makes the soil complicated to manage and unsuitable for sustainable use.…”

Phylogenetic diversity shapes salt tolerance in Phragmites australis estuarine populations in East China

“…The first five categories range from no to severe excess salt, while categories 6 and 7 include water bodies and permafrost areas. We compared the SQ5 layer with published soil salinity maps of the Yellow River Delta 16 , 51 – 53 and of the Yangtze River Delta 54 to ensure updated data and reproducibility of the SQ5 results. As some of our samples in the Yangtze River Delta were collected in areas that were still submersed in the SQ5 layer, we also mined salinity data from our own field work previously conducted at the sampling locations (Xiu Zhen-Li, unpublished data).…”