Dynamics of Soil Water and Salinity Under Subsurface Drainage of a Coastal Area With High Groundwater Table in Spring and Rainy Season

2016 ◽  
Vol 65 (3) ◽  
pp. 360-370 ◽  
Author(s):  
Shuhui Yu ◽  
Jintong Liu ◽  
A. Egrinya Eneji ◽  
Lipu Han ◽  
Limei Tan ◽  
...  
Keyword(s):  
Soil Water ◽  
Coastal Area ◽  
Rainy Season ◽  
Subsurface Drainage ◽  
Groundwater Table

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

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.

Subsurface Drainage Flow and Soil Water Dynamics of Reconstructed Prairies and Corn Rotations for Biofuel Production

2014 ◽  
Vol 13 (4) ◽  
pp. vzj2013.10.0177 ◽  
Author(s):  
Aaron L. Daigh ◽  
Xiaobo Zhou ◽  
Matthew J. Helmers ◽  
Carl H. Pederson ◽  
Robert Ewing ◽  
...  
Keyword(s):  
Soil Water ◽  
Subsurface Drainage ◽  
Water Dynamics ◽  
Biofuel Production ◽  
Soil Water Dynamics ◽  
Drainage Flow

4. Archaeological Sites in the Galápagos Group

1956 ◽  
Vol 12 ◽  
pp. 13-21
Author(s):  
Thor Heyerdahl ◽  
Arne Skjölsvold
Keyword(s):  
Coastal Area ◽  
Rainy Season ◽  
Fine Sand ◽  
Dry Season ◽  
Archaeological Sites ◽  
Northwest Coast ◽  
James Bay ◽  
Local Conditions ◽  
Santiago Island

The principal site discovered by the expedition is on the northwest coast of James Bay, Santiago Island. The local conditions for primitive settlement are conspiciously better in this bay than in any other coastal area visited by the expedition in the Galápagos. To a passing craft James Bay opens up wide and impressive, well sheltered by forest-clad mountains sufficiently withdrawn from the coast to leave space for a large and level plateau lifted up like a terrace above the fine sand beaches of the bay (Fig. 3). In the rainy season glittering streams of water appear on the sides of a cone-shaped volcano (Sugar Loaf) and reveal from far out at sea the likely location of waterholes. Even in the dry season there are one or 2 dependable waterholes a couple of miles inland at the foot of this hill.

The instantaneous transport of inorganic and organic material in a highly polluted tropical estuary

2013 ◽  
Vol 64 (6) ◽  
pp. 562 ◽  
Author(s):  
Carlos E. D. Noriega ◽  
Marilene Felipe Santiago ◽  
Patrícia Façanha ◽  
Maria da Glória Gonçalves da Silva Cunha ◽  
Rodolfo Araújo da Silva ◽  
...  
Keyword(s):  
Chlorophyll A ◽  
Coastal Area ◽  
Rainy Season ◽  
Phytoplankton Biomass ◽  
Dry Season ◽  
Tropical Estuary ◽  
Liquid Transport ◽  
Water Renewal ◽  
Rainy Period ◽  
Dissolved Inorganic Nutrients

The contribution of the estuarine channel of Recife harbour to the eutrophication of the Recife coastal area was evaluated by quantifying the instantaneous transport of salt, dissolved inorganic nutrients (PO4–, SiOH4, NO3–, NO2– and, NH4+), material in suspension, Chlorophyll-a, pico–nanoplankton and microplankton during the rainy (June 2007) and dry (November 2007) seasons. The results showed that all of the dissolved nitrogenated nutrients, the silicate and the material in suspension had higher concentrations during the rainy season, whereas the phosphate and Chlorophyll-a (both the total and the pico–nanoplankton and microplankton fractions) showed greater concentrations during the dry season. All of the materials considered were exported to the sea except for Chlorophyll-a (pico–nanoplankton and microplankton fractions) during the dry season, when these materials were imported into the area. The total liquid transport in the rainy season was three times higher than that found for the dry season. Silicate represented nearly 85% of the total exported material during the rainy period, whereas during the dry season, phosphate and silicate represented 79% of the total exported material. The stratification and circulation processes indicated a well mixed environment. The water-renewal rate was low, as demonstrated by the input of phytoplankton biomass during November. The area was characterised as eutrophic during the months investigated.

scholarly journals Reproduction of a whiptail lizard (Ameivula ocellifera, Teiidae) from a coastal area in northeastern Brazil

2014 ◽  
Vol 86 (3) ◽  
pp. 1263-1272 ◽  
Author(s):  
DJAN ZANCHI-SILVA ◽  
DIVA M. BORGES-NOJOSA ◽  
CONRADO A.B. GALDINO
Keyword(s):  
Body Size ◽  
Clutch Size ◽  
Coastal Area ◽  
Rainy Season ◽  
Female Body ◽  
The State ◽  
Northeastern Brazil ◽  
Egg Volume ◽  
Female Reproduction ◽  
Female Body Size

The reproductive ecology of Ameivula ocellifera was studied from September 2009 to August 2010 in a coastal area of the state of Ceará, Brazil. Females reproduced continuously throughout the year, with a peak at the end of the rainy season. Even though there was a predominance of pre-reproductive individuals in the sample, gonadal activity of males peaked synchronously to female reproduction. Mean clutch size was 1.98 ± 0.56 and positively associated with female body size, while mean egg volume was 510.54 ± 84.29 mm3 and unrelated to female body size. We did not find any association between clutch size and average egg volume.

scholarly journals Effects of Water and Salt Movement On Photosynthetic Production Characteristics and Yield Formation of Cotton On Coastal Saline Land

2021 ◽  
Author(s):  
Guoyi Feng ◽  
Qian Zhang ◽  
Chitao Sun ◽  
Xiaopeng Lei ◽  
Shulin Wang ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Water Content ◽  
Soil Water ◽  
Rainy Season ◽  
Reproductive Stage ◽  
Cotton Field ◽  
Alkali Stress ◽  
Photosynthetic Production ◽  
Yield Formation ◽  
Saline Land

Abstract Background In order to study the effects of spatial distribution and yearly migration variations of soil water and salt in coastal saline land on photosynthetic production and yield formation of cotton, spatial distribution characteristics of water content, salinity, and pH in soil at 0–200 cm depths in 3 cotton fields that were similar in locality but differed markedly in degree of salinization were determined in April through October, and photosynthetic characteristics and photosynthate accumulation of cotton were also determined. Results The study shows that, the slightly salinized cotton field had lower soil salinity and pH, where soil water content was lower in rainy season (July–August), and at the late reproductive stage (September–October), soil water content was markedly higher than that in the moderately salinized cotton field, where cotton suffered smaller salt-alkali stress, photosynthetic production matched well with hydrothermal resource, the sink organ had a long photosynthate accumulation time and was at the active material accumulation stage for a long time; salt-alkali stress to the moderately salinized cotton field was relieved in rainy season, but at the early reproductive stage (April–June) and the late reproductive stage of cotton, salt-alkali stress remained evident, and photosynthetic production fit more poorly with the rich photothermal resource stage; the severely salinized cotton field subjected to prolonged high salt-alkali stress resulted in low levels of photosynthetic production capacity and yield. Conclusions For the severely salinized cotton field, salt inhibition and other relevant agronomic actions should be taken with greater efforts; for the moderately salinized cotton field, water and fertilizer management should be tightened at the early reproductive stage of cotton; for the slightly salinized cotton field, high-quality efficient cotton production should be developed.

Sign in / Sign up

Export Citation Format

Share Document