Soil water use sources and patterns in shrub encroachment in semiarid grasslands of Inner Mongolia

In southern Florida, most tropical fruit crops between Biscayne and Everglades National Parks are irrigated at rates and frequencies based on experience and observations of tree growth and fruit yield rather than on reliable quantitative information of actual water use. This approach suggests that irrigation rates may be excessive and could lead to leaching of agricultural chemicals into the groundwater in this environmentally sensitive area. Therefore, a study is being conducted to increase water use efficiency and optimize irrigation by accurately scheduling irrigation using a very effective management tool (EnviroScan, Sentek Environmental Innovations, Pty., Kent, Australia) that continuously monitors soil water content with highly accurate capacitance multi-sensor probes installed at several depths within the soil profile. The system measures crop water use by monitoring soil water depletion rates and allows the maintenance of soil water content within the optimum range (below field capacity and well above the onset of plant water stress). The study is being conducted in growers' orchards with three tropical fruit crops (avocado, carambola, and `Tahiti' lime) to facilitate rapid adoption and utilization of research results.

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Changes in soil microbial community during shrub encroachment process in the Inner Mongolia grassland of northern China

CATENA ◽

10.1016/j.catena.2021.105230 ◽

2021 ◽

Vol 202 ◽

pp. 105230

Author(s):

Xia Hu ◽

Xiao-Yan Li ◽

Yunduo Zhao ◽

Zhou Gao ◽

Shao-Jie Zhao

Keyword(s):

Microbial Community ◽

Soil Microbial Community ◽

Inner Mongolia ◽

Northern China ◽

Shrub Encroachment ◽

Soil Microbial ◽

Inner Mongolia Grassland

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Contrasting Water Use Strategies of Tamarix ramosissima in Different Habitats in the Northwest of Loess Plateau, China

Water ◽

10.3390/w12102791 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2791

Author(s):

Pengyan Su ◽

Mingjun Zhang ◽

Deye Qu ◽

Jiaxin Wang ◽

Yu Zhang ◽

...

Keyword(s):

Soil Water ◽

Water Use ◽

Loess Plateau ◽

Meteoric Water ◽

Water Source ◽

Water Sources ◽

Tamarix Ramosissima ◽

Water Line ◽

Meteoric Water Line ◽

Utilization Ratio

As a species for ecological restoration in northern China, Tamarix ramosissima plays an important role in river protection, flood control, regional climate regulation, and landscape construction with vegetation. Two sampling sites were selected in the hillside and floodplain habitats along the Lanzhou City, and the xylems of T. ramosissima and potential water sources were collected, respectively. The Bayesian mixture model (MixSIAR) and soil water excess (SW-excess) were applied to analyze the relationship on different water pools and the utilization ratios of T. ramosissima to potential water sources in two habitats. The results showed that the slope and intercept of local meteoric water line (LMWL) in two habitats were smaller compared with the global meteoric water line (GMWL), which indicated the existence of drier climate and strong evaporation in the study area, especially in the hillside habitat. Except for the three months in hillside, the SW-excess of T. ramosissima were negative, which indicated that xylems of T. ramosissima are more depleted in δ2H than the soil water line. In growing seasons, the main water source in hillside habitat was deep soil water (80~150 cm) and the utilization ratio was 63 ± 17% for T. ramosissima, while the main water source in floodplain habitat was shallow soil water (0~30 cm), with a utilization ratio of 42.6 ± 19.2%, and the water sources were different in diverse months. T. ramosissima has a certain adaptation mechanism and water-use strategies in two habitats, and also an altered water uptake pattern in acquiring the more stable water. This study will provide a theoretical basis for plant water management in ecological environment protection in the Loess Plateau.

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Virtual Water Trade in the Yellow River Economic Belt: A Multi-Regional Input-Output Model

Water ◽

10.3390/w13060748 ◽

2021 ◽

Vol 13 (6) ◽

pp. 748

Author(s):

Ming Li ◽

Qingsong Tian ◽

Yan Yu ◽

Yueyan Xu ◽

Chongguang Li

Keyword(s):

Water Resources ◽

Water Use ◽

Inner Mongolia ◽

Yellow River ◽

Cumulative Risk ◽

Virtual Water ◽

Hot Water ◽

The Yellow River ◽

Input Output ◽

Virtual Water Trade

The sustainable and efficient use of water resources has gained wide social concern, and the key point is to investigate the virtual water trade of the water-scarcity region and optimize water resources allocation. In this paper, we apply a multi-regional input-output model to analyze patterns and the spillover risks of the interprovincial virtual water trade in the Yellow River Economic Belt, China. The results show that: (1) The agriculture and supply sector as well as electricity and hot water production own the largest total water use coefficient, being high-risk water use sectors in the Yellow River Economic Belt. These two sectors also play a major role in the inflow and outflow of virtual water; (2) The overall situation of the Yellow River Economic Belt is virtual water inflow, but the pattern of virtual water trade between eastern and western provinces is quite different. Shandong, Henan, Shaanxi, and Inner Mongolia belong to the virtual water net inflow area, while the virtual water net outflow regions are concentrated in Shanxi, Gansu, Xinjiang, Ningxia, and Qinghai; (3) Due to higher water resource stress, Shandong and Shanxi suffer a higher cumulative risk through virtual water trade. Also, Shandong, Henan, and Inner Mongolia have a higher spillover risk to other provinces in the Yellow River Economic Belt.

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Water use by winter wheat as affected by soil management

The Journal of Agricultural Science ◽

10.1017/s0021859600043458 ◽

1984 ◽

Vol 103 (1) ◽

pp. 189-199 ◽

Cited By ~ 11

Author(s):

M. J. Goss ◽

K. R. Howse ◽

Judith M. Vaughan-Williams ◽

M. A. Ward ◽

W. Jenkins

Keyword(s):

Winter Wheat ◽

Soil Water ◽

Water Deficit ◽

Water Use ◽

Management Practices ◽

Soil Management ◽

Maximum Depth ◽

Water Extraction ◽

Soil Water Deficit ◽

Potential Yield

SummaryIn each of the years from September 1977 to July 1982 winter wheat was grown on one or more of three clay soil sites (clay content 35–55%) in Oxfordshire where the climate is close to the average for the area of England growing winter cereals.The effects on crop water use of different soil management practices, including ploughing, direct drilling and subsoil drainage, are compared. Cultivation treatment had little effect on the maximum depth of water extraction, which on average in these clay soils was 1·54 m below the soil surface. Maximum soil water deficit was also little affected by cultivation; the maximum recorded value was 186±7·6 mm. Subsoil drainage increased the maximum depth of water extraction by approximately 15 cm and the maximum soil water deficit by about 17 mm.Generally soil management had little effect on either total water use by the crop which was found to be close to the potential evaporation estimated by the method of Penman, or water use efficiency which for these crops was about 52 kg/ha par mm water used.Results are discussed in relation to limitations to potential yield.

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Intensified Interspecific Competition for Water after Afforestation with Robinia pseudoacacia into a Native Shrubland in the Taihang Mountains, Northern China

Sustainability ◽

10.3390/su13020807 ◽

2021 ◽

Vol 13 (2) ◽

pp. 807

Author(s):

Wanrui Zhu ◽

Wenhua Li ◽

Peili Shi ◽

Jiansheng Cao ◽

Ning Zong ◽

...

Keyword(s):

Soil Water ◽

Introduced Species ◽

Water Use ◽

Rainy Season ◽

Robinia Pseudoacacia ◽

Water Source ◽

Total Water ◽

Mountainous Areas ◽

Water Competition ◽

Seasonal Water Use

Understanding how soil water source is used spatiotemporally by tree species and if native species can successfully coexist with introduced species is crucial for selecting species for afforestation. In the rocky mountainous areas of the Taihang Mountains, alien Robinia pseudoacacia L. has been widely afforested into the native shrublands dominated by Ziziphus jujuba Mill var. spinosa and Vitex negundo L. var. heterophylla to improve forest coverage and soil nutrients. However, little is known about the water relation among species, especially seasonal water use sources in different microsites. We selected the soil and plant xylem samples of two opposite microtopographic sites (ridge and valley) monthly in the growth season to analyze isotope composition. The proportions of water sources were quantified by the MixSIAR model and compared pairwise between species, microsites and seasons. We found that deep subsoil water at a depth of 40–50 cm contributed up to 50% of the total water uptake for R. pseudoacacia and Z. jujuba in the growing season, indicating that they stably used deeper soil water and had intense water competition. However, V. negundo had a more flexible water use strategy, which derived more than 50% of the total water uptake from the soil layer of 0–10 cm in the rainy season, but majorly captured soil water at a depth of 30–50 cm in the dry season. Therefore, high niche overlaps were shown in V. negundo with the other two species in the dry season, but niche segregation was seen in the rainy season. The microtopographic sites did not shift the seasonal dynamic of the water source use patterns of the three studied species, but the water use niche overlap was higher in the valley than in the ridge. Taken together, the introduced species R. pseudoacacia intensified water competition with the native semi-arbor species Z. jujuba, but it could commonly coexist with the native shrub species V. negundo. Therefore, our study on seasonal water use sources in different microsites provides insight into species interaction and site selection for R. pseudoacacia afforestation in the native shrub community in rocky mountainous areas. It is better to plant R. pseudoacacia in the shrubland in the valley so as to avoid intense water competition and control soil erosion.

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