scholarly journals Influence of Gully Land Consolidation on Phreatic Water Transformation in the Loess Hilly and Gully Region

Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 538
Author(s):  
Zihao Guo ◽  
Jianen Gao ◽  
Pengcheng Sun ◽  
Shaohui Dou ◽  
Juan Li ◽  
...  
Keyword(s):  
Crop Yields ◽  
Field Application ◽  
Land Consolidation ◽  
Transformation Rate ◽  
Soil Thickness ◽  
Phreatic Water ◽  
Artificial Rainfall ◽  
Outflow Rate ◽  
Water Outflow ◽  
The Relationship

Gully Land Consolidation (GLC) is a proven method to create farmlands and increase crop yields in the Loess Hilly and Gully Region, China. However, GLC influences phreatic water transformation and might cause the farmlands water disasters, such as salinization and swamping. For exploring the influence of GLC on phreatic water transformation and mitigating disasters, a series of indoor experiments were conducted in the artificial rainfall hall. Then, we simulated the phreatic water transformation patterns under more conditions with HYDRUS-3D. Finally, an engineering demonstration in the field was performed to validate our research. The indoor experiments indicated that GLC could increase phreatic water outflow rate 4.39 times and phreatic water coefficient (PWC) 2.86 times with a considerable delay. After calibration and validation with experimental data, the HYDRUS-3D was used to simulate phreatic water transformation under more soil thickness and rainfall intensities. Accordingly, we summarized the relationship among PWC, rainfall intensities, and soil thickness, and therefore suggested a blind ditch system to alleviate farmlands disasters. Field application showed that a blind ditch system could avoid disasters with 3.2 times the phreatic water transformation rate compared to loess. Our research provides implications for sustainable land uses and management in the region with thick soil covers.

Phosphorus Retention Capacity of Lakes

1976 ◽  
Vol 33 (8) ◽  
pp. 1742-1750 ◽  
Author(s):  
D. P. Larsen ◽  
H. T. Mercier
Keyword(s):  
Water Supply ◽  
Trophic State ◽  
Retention Capacity ◽  
Lake Volume ◽  
Outflow Rate ◽  
Annual Water ◽  
Water Outflow ◽  
Function Of Two Variables ◽  
The Relationship ◽  
Best Fit

Mean annual lake phosphorus concentrations [Formula: see text] in a steady state system can be described as a function of two variables, the mean annual influent P concentration and the net annual P sedimentation: [Formula: see text] (see Rigler 1975). [Formula: see text] is the annual P supply/annual water supply and Rp is that fraction of inflowing P retained by the sediments annually. Since Rp is critical in determining [Formula: see text], lake properties were examined for their influence on Rp; the best fit empirical expressions developed related Rp to either areal water supply (annual water inflow rate/lake surface area) or hydraulic washout coefficient (annual water outflow rate/lake volume). The expressions were derived from characteristics of low productivity lakes; their validity for more productive lakes was not examined.A graph of [Formula: see text] vs. Rp is proposed to illustrate the relationship between [Formula: see text], [Formula: see text], and Rp, and, if lake P concentrations are used as measures of trophic state, this graph is useful for predicting trophic state and changes in trophic state caused by altering [Formula: see text] and/or Rp. It is conceptually similar to those of Vollenweider (1975) and Dillon (1975) but differs in that it separates the potential lake concentration ([Formula: see text] would be equal to [Formula: see text] if P were conservative) from those factors acting to reduce [Formula: see text], expressed as Rp, to produce lake concentrations.

scholarly journals Analysis of Ownership Data from Consolidated Land Threatened by Water Erosion in the Vlára Basin, Slovakia

2020 ◽  
Vol 13 (1) ◽  
pp. 51
Author(s):  
Alexandra Pagáč Mokrá ◽  
Jakub Pagáč ◽  
Zlatica Muchová ◽  
František Petrovič
Keyword(s):  
Soil Erosion ◽  
Soil Loss ◽  
Agricultural Land ◽  
Water Erosion ◽  
Land Consolidation ◽  
Land Fragmentation ◽  
Erosion Risk ◽  
Definition Of ◽  
The Relationship ◽  
Soil Loss Equation

Water erosion is a phenomenon that significantly damages agricultural land. The current land fragmentation in Slovakia and the complete ambiguity of who owns it leads to a lack of responsibility to care for the land in its current condition, which could affect its sustainability in the future. The reason so much soil has eroded is obvious when looking at current land management, with large fields, a lack of windbreaks between them, and no barriers to prevent soil runoff. Land consolidation might be the solution. This paper seeks to evaluate redistributed land and, based on modeling by the Universal Soil Loss Equation (USLE) method, to assess the degree of soil erosion risk. Ownership data provided information on how many owners and what amount of area to consider, while taking into account new conditions regarding water erosion. The results indicate that 2488 plots of 1607 owners which represent 12% of the model area are still endangered by water erosion, even after the completion of the land consolidation project. The results also presented a way of evaluating the territory and aims to trigger a discussion regarding an unambiguous definition of responsibility in the relationship between owner and user.

scholarly journals Effect of Three Ca Sources Applied On Peanuts I. Productivity and Seed Quality1

1980 ◽  
Vol 7 (1) ◽  
pp. 19-25 ◽  
Author(s):  
D. L. Hallock ◽  
A. H. Allison
Keyword(s):  
Crop Yields ◽  
Relative Effectiveness ◽  
Correlation Coefficients ◽  
Early Flowering ◽  
Lower Yield ◽  
Flowering Stage ◽  
Arachis Hypogaea L ◽  
Dry Conditions ◽  
Increase Productivity ◽  
The Relationship

Abstract The relative effectiveness of United States Gypsum granular 420 Landplaster Bulk (420-Bulk) and Texasgulf Gypsum (Tg Gypsum) were compared with finely ground anhydrite (Bagged-LP) as sources of supplemental Ca for Florigiant peanuts (Arachis hypogaea L.). Treatments included the above sources at rates of 605 kg/ha banded (61 cm) or 907 kg/ha broadcast (91-cm wide rows) of CaSO4 equivalent per unit area covered (double these rates of 420-Bulk and Bagged-LP also were applied in 1977). Times of application were planting, planting + ca 30 days, and early flowering stage. The experiments were located on Kenansville lfs (Arenic Hapludult) in 1977 and on Rumford lfs (Typic Hapludult) in 1978. The Ca treatments increased crop yields from 360 to 1,200 kg/ha and crop value (yield × price) from $343 to $889/ha over the check in 1977. Slightly lower yield increases were obtained in 1978 when dry conditions prevailed during fruit maturation. Kernel size grades were improved markedly by all Ca treatments in 1977. There was a definite trend both years (significant in 1978) toward higher productivity when the Ca sources were applied at the early flowering stage compared to earlier applications. No difference was noted between methods of application of Bagged-LP or Tg Gypsum in 1978. Double rates of Bagged-LP or 420-Bulk in 1977 did not increase productivity over the low rates. A single application of Bagged-LP was as effective as split applications in the 1978 test. Germinability of seed in 1977 averaged 85% or higher for all Ca treatments. Seed germination in 1978 averaged 75%, 69% and 74% in plots where Tg Gypsum, 420-Bulk or Bagged-LP was applied, respectively. Germination was lowest in the check plots both years. Germinability and seed-Ca contents were significantly higher in 1978 when the Ca sources were applied at the early flowering stage (ca July 1) than 15 days earlier. Seed-Ca contents both years and K contents in 1978 were significantly correlated with germinability. The correlation coefficients were only 0.4 in each case and the relationship was negative for K. In general, 420-Bulk, Tg Gypsum, or Bagged-LP were equally effective sources of supplemental Ca for peanuts. However, when fruit mature under very dry conditions 420-Bulk may be somewhat inferior to the other Ca sources especially when applied before early flowering.

scholarly journals Agroecological Determinants of Potato Spatiotemporal Yield Variation at the Landscape Level in the Central and Northern Ukraine

2021 ◽  
Vol 4 (2) ◽  
pp. 34-47
Author(s):  
Anastasiia Zymaroieva ◽  
Tetiana Fedoniuk ◽  
Svitlana Matkovska ◽  
Olena Andreieva ◽  
Victor Pazych
Keyword(s):  
Crop Yields ◽  
Climatic Factors ◽  
High Sensitivity ◽  
Potato Yield ◽  
Limiting Factors ◽  
Forest Steppe ◽  
Yield Parameters ◽  
Bioclimatic Variables ◽  
Potato Yields ◽  
The Relationship

Global food security largely depends on the crop yield increase, so the study of the yield-limiting factors of potato (the second bread) is a pressing issue today. This study determines the contribution of the agroecological factors, namely, bioclimatic variables, soil indicators, and factors of landscape diversity, to the variation in potato yields. Conducted in Polissya and Forest-steppe zones of Ukraine during 1991–2017, this study has not only addressed the relationship between ecological determinants and potato yields, but also considered crop yields as a dynamic system. The dynamics of potato yields from the mid-1990s to the present is described by a log-logistic model. There are statistically significant regression dependencies between potato yield parameters and agroecological factors. Potato yield is dependent on the diversity of landscape cover. The relationship between yield parameters and landscape-ecological diversity is non-linear, which determines the presence of optimal landscape structure for the highest potato yields. Among climatic factors, the continental climate is of the greatest importance for potato yield. The high sensitivity of potato yield parameters to soil indices was found, and mostly the soil texture components (silt content), which largely determines the potato yield spatial variation.

Dewatering Preloading Test and Ground Subsidence in a Project

2011 ◽  
Vol 250-253 ◽  
pp. 1912-1916
Author(s):  
Yong Mou Zhang ◽  
Jian Chang Zhao
Keyword(s):  
Water Level ◽  
Pore Water Pressure ◽  
Water Pressure ◽  
New Technology ◽  
Soft Soil ◽  
Soil Treatment ◽  
Ground Subsidence ◽  
Confined Water ◽  
Phreatic Water ◽  
The Relationship

Ground subsidence is one of the main geological hazards in Shanghai. The ground subsidence is caused by pumping groundwater greatly. In the past, studies of ground subsidence in Shanghai were mostly taken for the ground subsidence caused by pumping confined water in Puxi. And ground subsidence caused by pumping phreatic water was rarely studied. Dewatering preloading is a new technology for soft soil treatment. The monitoring of ground water level, ground subsidence, pore water pressure in the process of dewatering preloading test for a soft soil treatment project in Pudong showed that pumping phreatic water can also cause ground subsidence. The ground subsidence caused by pumping phreatic water was analyzed in this paper. The relationship between phreatic water level and ground subsidence was obtained.

The reclamation of land covered with pulverized fuel ash. The influence of soil depth on crop performance

1963 ◽  
Vol 61 (3) ◽  
pp. 299-308 ◽  
Author(s):  
D. R. Hodgson ◽  
R. Holliday ◽  
F. Cope
Keyword(s):  
Crop Yield ◽  
Crop Yields ◽  
Soil Depth ◽  
Land Restoration ◽  
Response Curves ◽  
Fertilizer Response ◽  
Fuel Ash ◽  
Pulverized Fuel ◽  
Pulverized Fuel Ash ◽  
The Relationship

1. A review of land restoration problems in relation to the soil depth required for successful crops showed that factual information on this orthodox method of restoration was inadequate.2. A field trial sited on pulverized fuel ash is described in which the relationship between crop yield and soil depth at a range of fertilizer levels was determined; kale, oats, rape, barley and potatoes were the test crops.3. The crops were divided into two groups, sensitive (kale and barley) and tolerant (oats, rape, potatoes) to ash toxicity, on the basis of their response to soil depth at the high fertilizer level. Quadratic expressions relating yield to soil depth, over the range 3–36 in. at each fertilizer level were fitted to the data for each crop group.4. Yield isoquants, derived from the fertilizer response curves at each soil depth, enabled soil depth-fertilizer level combinations to be ascertained for producing a given level of crop yield. Fertilizer could be substituted for soil more effectively for tolerant than sensitive crops.5. A 12 in. cover of soil together with 1½ times the normal farm fertilizer dressing for the crop was the minimum for acceptable yields. Fertilizer use may have to be increased to twice normal dressings to maintain yields if soil depths are reduced to below 12 in.6. Crop yields were not increased by a soil covering greater than 24 in. deep.

scholarly journals The use of intragastric nutrition to study saliva secretion and the relationship between rumen osmotic pressure and water transport

1995 ◽  
Vol 73 (2) ◽  
pp. 155-161 ◽  
Author(s):  
G. Y. Zhao ◽  
M. Durić ◽  
N. A. Macleod ◽  
E. R. ØRskov ◽  
F. D. Deb. Hovell ◽  
...  
Keyword(s):  
Linear Relationship ◽  
Osmotic Pressure ◽  
Water Transport ◽  
Rumen Fluid ◽  
Salivary Secretion ◽  
Saliva Secretion ◽  
Key Factor ◽  
The Difference ◽  
Water Outflow ◽  
The Relationship

Four sheep sustained by intragastric nutrition were used to study saliva secretion and the relationship between osmotic pressure in the rumen and net water transport across the rumen wall. Different concentrations of buffer were infused into the rumen to change the rumen osmotic pressure. Salivary secretion was estimated from entrance of P into the rumen. Net water transport across the rumen wall was calculated as the difference between water inflow and water outflow from the rumen. A negative linear relationship between the rumen osmotic pressure (X, mOsm/kg) and the water absorption across the rumen wall (Y, ml/h) was found: Y = (394 SE 8·3)–(l·22 SE 0·03) X, r20·83, (P < 0·001), and a positive linear relationship was found between the rumen osmotic pressure (X, mOsm /kg) and the outflow rate of rumen fluid (Y, ml/h): Y = (34·0 SE 8·0) + (0·97 SE 0·03), X, r2 0·56, (P < 0·001). The implication is that rumen osmotic pressure can be a key factor in the control of the net water transport across the rumen wall, the outflow of rumen fluid to omasum and the rumen liquid dilution rate. A method is suggested by which salivary secretion in sheep may be calculated from the water balance in the rumen.

scholarly journals Evaluating the spatial heterogeneity of soil loss tolerance and its effects on erosion risk in the carbonate areas of South China

2016 ◽  
Author(s):  
Yue Li ◽  
Xiaoyong Bai ◽  
Shijie Wang ◽  
Luoyi Qin ◽  
Yichao Tian ◽  
...  
Keyword(s):  
Spatial Heterogeneity ◽  
South China ◽  
Soil Loss ◽  
Carbonate Rock ◽  
Soil Thickness ◽  
Clastic Rock ◽  
Erosion Risk ◽  
Soil Loss Tolerance ◽  
Loss Tolerance ◽  
The Relationship

Abstract. Soil loss tolerance (T value) is the ultimate criterion to determine the necessity of erosion control measures and ecological restoration strategy. However, the validity of this criterion in subtropical karst regions is strongly disputed. In this study, T value is computed based on soil formation rate by using a digital distribution map of carbonate rock assemblage types. Results indicated spatial heterogeneity and diversity in such values; moreover, a minimum of three criteria should be considered instead of only one criterion when investigating the carbonate areas of South China given that the “one region, one T value” concept may not apply to this region. T value is proportionate to the amount of argillaceous material in formations that determine surface soil thickness in homogenous carbonate rock areas; such values are 20 and 50 t/(km2 · a) in carbonate rock intercalated with clastic rock areas and 100 t/(km2 · a) in carbonate/clastic rock alternation areas. These three areas are each extremely, severely, and moderately sensitive to soil erosion. This erosion is extreme in karst rocky desertification (KRD) land and reflects the degree of erosion risk. Thus, the relationship between T value and erosion risk is determined with KRD as a parameter. The existence of KRD land is unrelated to T value, although this parameter indicates erosion sensitivity. In fact, erosion risk is strongly dependent on the relationship between real soil loss (RL) and T value rather than on either erosion intensity or the T value itself. If RL >> T, then erosion risk is high despite a low RL. Conversely, if T >> RL, the soil is safe although RL is high. Overall, these findings may clarify T value heterogeneity and its effect on erosion risk in a karst eco-environment; hence, innovative technological assessment solutions need not be invented.

scholarly journals PELINDIAN UNSUR KALIUM (K) DAN NATRIUM (Na) MATERIAL VULKANIK HASIL ERUPSI GUNUNG MERAPI 2010 (Simulasi Laboratorium)

2014 ◽  
Vol 29 (2) ◽  
pp. 87
Author(s):  
Taufiq Perak Sanjaya ◽  
Jauhari Syamsiyah ◽  
Dwi Priyo Ariyanto ◽  
Komariah Komariah
Keyword(s):  
Previous Treatment ◽  
Rainfall Simulation ◽  
Volcanic Material ◽  
Central Java ◽  
Artificial Rainfall ◽  
Randomized Design ◽  
Sample Depth ◽  
The Mean ◽  
And Control ◽  
The Relationship

<p>This research was conducted at the Greenhouse Laboratory of the Faculty of Agriculture, Sebelas Maret University Surakarta, in March 2011. The aim of the study was to determine the relationship between the rainfall (synthetic) the number of elements Potassium (K) and Sodium (Na) were leached in volcanic material from the eruption of Mount Merapi. This study used artificial rainfall simulation approach to treatment is based on the phenomenon of the eruption of Mount Merapi, Yogyakarta, Central Java by examining the leaching elements Sodium (Na) and Potassium (K) are swapped in the above-ground volcanic material Andisol. The experiments in this study using a completely randomized design (CRD) consisting of 3 to 5 treatments the sample depth artificial rain (water sprinkling) in 3 replications, namely 1 (22 mm x 1 day (22 mm)), 2 (22 mm x 10 days (220 mm)), 3 (22 mm x 20 days (440 mm)), 4 (22 mm x 30 days (660 mm)), 5 (22 mm x 45 days (990 mm)), and control ( 45 days field) with 3 replicates each. The variables measured were pH H2O, available K and Na, K and Na total, CEC, texture. Analysis of the data using the F test at the level of 95% or Kruskal-Wallis, to compare the mean between treatments using DMR test at the level of 95% or Mood Median, whereas to determine the relationship between variables used correlation test. The results showed that administration of rainfall of 22 mm / day is able to affect the leaching of potassium and sodium in the volcanic material from day 10. Leaching was significantly visible on day 30 with a decrease in available K and Na volcanic material at a depth of 0-15 cm in diameter (K 23.08%) (23.08% Na) and at a depth of 15-30 cm (K 21, 42%) (23.08% Na), and the addition of K and Na are available at a depth of &gt;30 cm in the form of land Andisol (K 16.67%) (23.53% Na) from the previous treatment.</p>

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