How dam construction affects the activity of alkaline phosphatases in reservoir sediments: A study of two highly regulated rivers

2021 ◽  
pp. 112236
Author(s):  
Juan Chen ◽  
Peifang Wang ◽  
Chao Wang ◽  
Xun Wang ◽  
Han Gao ◽  
...  
Keyword(s):  
Dam Construction ◽  
Alkaline Phosphatases ◽  
Regulated Rivers ◽  
Reservoir Sediments

scholarly journals Relative Contribution of the Xiaolangdi Dam to Runoff Changes in the Lower Yellow River

Land ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 521
Author(s):  
Qinghe Zhao ◽  
Shengyan Ding ◽  
Xiaoyu Ji ◽  
Zhendong Hong ◽  
Mengwen Lu ◽  
...  
Keyword(s):  
Climate Change ◽  
Human Activities ◽  
Sustainable Management ◽  
Yellow River ◽  
Dam Construction ◽  
Regulated Rivers ◽  
Flood Season ◽  
Abrupt Changes ◽  
Runoff Changes ◽  
Seasonal Runoff

Human activities are increasingly recognized as having a critical influence on hydrological processes under the warming of the climate, particularly for dam-regulated rivers. To ensure the sustainable management of water resources, it is important to evaluate how dam construction may affect surface runoff. In this study, using Mann–Kendall tests, the double mass curve method, and the Budyko-based elasticity method, the effects of climate change and human activities on annual and seasonal runoff were quantified for the Yellow River basin from 1961–2018; additionally, effects on runoff were assessed after the construction of the Xiaolangdi Dam (XLD, started operation in 2001) on the Yellow River. Both annual and seasonal runoff decreased over time (p < 0.01), due to the combined effects of climate change and human activities. Abrupt changes in annual, flood season, and non-flood season runoff occurred in 1986, 1989, and 1986, respectively. However, no abrupt changes were seen after the construction of the XLD. Human activities accounted for much of the reduction in runoff, approximately 75–72% annually, 81–86% for the flood season, and 86–90% for the non-flood season. Climate change approximately accounted for the remainder: 18–25% (annually), 14–19% (flood season), and 10–14% (non-flood season). The XLD construction mitigated runoff increases induced by heightened precipitation and reduced potential evapotranspiration during the post-dam period; the XLD accounted for approximately 52% of the runoff reduction both annually and in the non-flood season, and accounted for approximately −32% of the runoff increase in the flood season. In conclusion, this study provides a basic understanding of how dam construction contributes to runoff changes in the context of climate change; this information will be beneficial for the sustainable management of water resources in regulated rivers.

New Method of Dam Construction

1903 ◽  
Vol 55 (1413supp) ◽  
pp. 22648-22648
Author(s):  
J. Francis Le Baron
Keyword(s):  
New Method ◽  
Dam Construction

Progestation

1967 ◽  
Vol 56 (3_Suppla) ◽  
pp. S7-S45 ◽  
Keyword(s):  
Tritiated Thymidine ◽  
Succinic Dehydrogenase ◽  
Glandular Epithelium ◽  
Synthetic Activity ◽  
Cell Renewal ◽  
Pulse Labelling ◽  
Uterine Receptivity ◽  
Alkaline Phosphatases ◽  
Monocytic Cells ◽  
Acid And Alkaline Phosphatases

ABSTRACT Autoradiographic, enzymic and histologic studies on uteri of pregnant rats were carried out to follow the endometrial modifications which take place during progestation (days L0 – L4) and culminate in the state of uterine receptivity essential for ovum-implantation. Pulse labelling with tritiated thymidine (radioactive DNA precursor) on L0, L1 and L2 revealed a sequence of cell renewal in luminal and glandular epithelium and endometrial stroma. On L3 and L4 stromal cells showed extensive incorporation of tritiated thymidine. This synthetic activity was associated with endometrial preparation for decidualization and was evoked at least in part, by the surge of oestrogen on L3. All layers of the uterine wall were heavily infiltrated on L0 and resembled the site of an acute inflammatory reaction. Subsequently, polymorphonuclear infiltration diminished and monocytic cells predominated. On L3 a spatial arrangement was observed: eosinophiles were concentrated in the basal endometrium and monocytic cells in the subepithelial stroma. A comparison was made between such a shift in migratory cells in the uterus and similar phenomena which occur in inflammatory and immune reactions. Activities of acid and alkaline phosphatases, of ATP-ase and succinic dehydrogenase were low on L0 and L1 during the periods of infiltration, degeneration and regeneration of luminal and glandular epithelium. Enzymic activities increased on the following days, (L3 and L4). Vascular dilation and engorgement and endometrial oedema were observed near the blastocysts on L4. Most blastocysts incorporated tritiated thymidine after 14.00 h on L4, but some showed uptake before loss of the zona which occurs usually between 14.00 and 16.00 h; therefore, it was assumed that the permeability of the zona increases prior to being shed. Activities of succinic dehydrogenase and acid and alkaline phosphatases were demonstrable in blastocysts on L4 while they were still »free« in the uterine lumen.

Soil response to chemicals used in a field experiment

2013 ◽  
Vol 27 (2) ◽  
pp. 151-158 ◽  
Author(s):  
S. Jezierska-Tys ◽  
A. Rutkowska
Keyword(s):  
Alkaline Phosphatase ◽  
Enzymatic Activity ◽  
Field Experiment ◽  
Soil Microorganisms ◽  
Block Design ◽  
Soil Samples ◽  
Alkaline Phosphatases ◽  
Soil Response ◽  
Negative Effect ◽  
Set Up

Abstract The effect of chemicals (Reglone 200 SL and Elastiq 550 EC) on soil microorganisms and their enzymatic activity was estimated. The study was conducted in a field experiment which was set up in the split-block design and comprised three treatments. Soil samples were taken six times, twice in each year of study. The results showed that the application of chemicals generally had no negative effect on the number of soil microorganisms. The application of Reglone 200 SL caused an increase of proteolytic and ureolytic activity and affected the activity of dehydrogenases, acid and alkaline phosphatases in the soil. The soil subjected of Elastiq 550 EC was characterized by lower activity of dehydrogenases, protease, urease and alkaline phosphatase.

Effects of Kanwa on Rat Gastrointestinal Phosphatases

2010 ◽  
Vol 3 (3) ◽  
pp. 1147-1152
Author(s):  
Jacob Bamaiyi ◽  
Omajali ◽  
Sanni Momoh
Keyword(s):  
Alkaline Phosphatase ◽  
Small Intestine ◽  
Acid Phosphatase ◽  
Sodium Carbonate ◽  
Elevated Level ◽  
Food Additive ◽  
Alkaline Phosphatases ◽  
Acid And Alkaline Phosphatases ◽  
Diagnostic Indices ◽  
High Level

This study investigates the effects of kanwa on rat gastrointestinal phosphatases. The rats were administered 7% w/v concentration of  trona (Kanwa) orally for a period of two weeks in order to investigate how this compound is being used as food additive in some homes in Nigeria. The Kanwa used in this study was the handpicked variety obtained from sellers from Anyigba market in eastern part of Kogi State, Nigeria. Kanwa, a hydrated sodium carbonate (Na2CO3NaHCO3.2H2O) was obtained as a dried lake salt. Acid phosphatase has the ability to dephosphorylate molecules containing phosphate group. The decreased and elevated level in serum or plasma acid and alkaline phosphatases serves as diagnostic indices for various diseases. Results showed that there was increase and decrease of acid phosphatase (ACP) activities in both the stomach and small intestine. The activities of alkaline phosphatase (ALP) fluctuated in the small intestine. However, in the stomach, an increase activity of ALP was noticed throughout the period of ‘Kanwa’ administration. We concluded that although the level of ‘Kanwa’ consumed in most homes may not be toxic if not taken continuously or repeatedly. Thus, continuous consumption should be discouraged as accumulation of high level of ‘Kanwa’ may cause damages or injuries to the various organs/tissues and may disrupt normal body function.

scholarly journals SPX-related genes regulate phosphorus homeostasis in the marine phytoplankton, Phaeodactylum tricornutum

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Kaidian Zhang ◽  
Zhi Zhou ◽  
Jiashun Li ◽  
Jingtian Wang ◽  
Liying Yu ◽  
...  
Keyword(s):  
Stress Responses ◽  
Phaeodactylum Tricornutum ◽  
Response Regulator ◽  
P Uptake ◽  
Negative Regulator ◽  
Marine Phytoplankton ◽  
Alkaline Phosphatases ◽  
Phosphate Starvation Response ◽  
Essential Nutrient ◽  
Global Oceans

AbstractPhosphorus (P) is an essential nutrient for marine phytoplankton. Maintaining intracellular P homeostasis against environmental P variability is critical for phytoplankton, but how they achieve this is poorly understood. Here we identify a SPX gene and investigate its role in Phaeodactylum tricornutum. SPX knockout led to significant increases in the expression of phosphate transporters, alkaline phosphatases (the P acquisition machinery) and phospholipid hydrolases (a mechanism to reduce P demand). These demonstrate that SPX is a negative regulator of both P uptake and P-stress responses. Furthermore, we show that SPX regulation of P uptake and metabolism involves a phosphate starvation response regulator (PHR) as an intermediate. Additionally, we find the SPX related genes exist and operate across the phytoplankton phylogenetic spectrum and in the global oceans, indicating its universal importance in marine phytoplankton. This study lays a foundation for better understanding phytoplankton adaptation to P variability in the future changing oceans.

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