scholarly journals Effect of Vegetation Diversity on Erosion Rate

AGRIFOR ◽  
2018 ◽  
Vol 17 (2) ◽  
pp. 355
Author(s):  
Sri Sarminah ◽  
Farha Shera Prititania ◽  
Karyati .
Keyword(s):  
Surface Runoff ◽  
Erosion Rate ◽  
Soil Mass ◽  
Linear Analysis ◽  
Soil Types ◽  
Vegetation Diversity ◽  
High Rainfall ◽  
Schima Wallichii ◽  
The Relationship ◽  
Danger Level

The climate in Indonesia is a tropical climate with high rainfall, making Indonesia vulnerable to erosion. In addition to high rainfall, vegetation, slope and soil types also affect erosion. This study aims to determine the Important Value of Species (NPJ), the relationship between rainfall and surface runoff and the mass of eroded soil and the level of erosion hazard at different vegetation densities. Important Value The highest types of the three dominating types in plot I were Schima wallichii 115.12%, Macaranga gigantea 69.38% and Cratoxylum sumatranum 44.69%. Whereas in plot II the highest NPJ value of three types dominates, namely Macaranga gigantea 59.13%, Litsea angulata 39.52% and Aquilaria mallacensis 35.37%. The amount of eroded soil mass that occurred in PUE I was 0.13 tons / ha / year and PUE II was 0.19 tons / ha / year. Simple linear analysis of the relationship between rainfall and eroded soil mass at PUE I has a correlation value (r) = 0.79 with the equation Y = -8.34 + 0.39X, whereas in PUE II the correlation value (r) = 0.90 with the equation Y = -12.96 + 0.56X. The danger level of erosion (TBE) in PUE I and PUE II was very mild (erosion rate <15 tons / ha / year, Bahya Erosion I class with soil solum depth> 90 cm).

scholarly journals Effect of Slope on Infiltration Capacity and Erosion of Mount Merapi Slope Materials

2020 ◽  
Vol 1000 (1000) ◽  
Author(s):  
Adam Pamudji Rahardjo
Keyword(s):  
Surface Runoff ◽  
Erosion Rate ◽  
Soil Surface ◽  
Infiltration Rate ◽  
Infiltration Capacity ◽  
Erosion Rates ◽  
Slope Steepness ◽  
Balance Principle ◽  
Exponential Equations ◽  
The Relationship

 Infiltration which occurs on slope has a specific behavior that can be parameterized. One of the reasons is because the slope generates less ponding on the sloping soil surface. This condition affects infiltration rate and surface runoff proportion of water from any kind of rainfall distribution in time. Since surface runoff tends to be higher, erosion rate is also to be higher on slope. The slope steepness is the most important parameter of a slope. In this study, the effect of slope steepness on infiltration capacity and erosion rate of Mount Merapi bare slope material were tested in a laboratory using rainfall simulator. Three values of slope steepness of 36%, 47%, and 58% were used. The rainfall intensity was set constant and was found has rate of 116,312 mm/hour. The infiltration rate was measured by volumetric balance principle and the erosion rates were measured by collecting the eroded grains at the downstream end tank. Infiltration rate was evaluated by using Horton method and the average erosion were analyzed from the eroded grain data for each test. After fitting the recorded infiltration rate data to the Horton equation, the infiltration capacity was obtained. The results were the relationship between slope steepness and the affected the infiltration capacity and erosion for each test. Infiltration capacity is found to increase and the decrease with the increase of slope steepness while erosion rate is found to increase on the steeper slope. The increase of erosion range is between 15% to 33% for each 1o increase of slope steepness. In addition, polynomial and exponential equations were developed to express the relationship between slope steepness and infiltration capacity and also the erosion rate.

LACTOSE-FERMENTING BACTERIA FROM THE INTESTINAL CONTENTS OF MARINE FISH

1933 ◽  
Vol 8 (1) ◽  
pp. 291-300 ◽  
Author(s):  
NORMAN E. GIBBONS
Keyword(s):  
Marine Fish ◽  
Marine Fishes ◽  
Soil Types ◽  
Intestinal Contents ◽  
Fermenting Bacteria ◽  
Relationship Of ◽  
The Relationship ◽  
Contaminated Waters

From 112 marine fishes examined for the presence of lactose-fermenting bacteria, 31 strains were isolated which produced acid and gas in this sugar and 3 which produced acid only.Ten strains belonged to the genus Aerobacter, 8 being Aer. aerogenes and 2 probably varieties of Aer. cloacae. Nine were soil types and the relationship of one was doubtful.Of 24 Escherichia types, 8 were faecal mammalian strains and one was doubtful. These belonged to the species Esch. coli, Esch. communior, Esch. grünthali and Bact. immobilis. One was found in a haddock taken 3 miles offshore; the others were found in fish taken in contaminated waters or near shore.Esch. coli, Esch. communior and Aer. aerogenes are not normal inhabitants of the intestinal tracts of marine fish.

scholarly journals Soil Nutrient and Vegetation Diversity Patterns of Alpine Wetlands on the Qinghai-Tibetan Plateau

2021 ◽  
Vol 13 (11) ◽  
pp. 6221
Author(s):  
Muyuan Ma ◽  
Yaojun Zhu ◽  
Yuanyun Wei ◽  
Nana Zhao
Keyword(s):  
Species Diversity ◽  
Tibetan Plateau ◽  
Soil Properties ◽  
Soil Ph ◽  
Plant Biomass ◽  
Principal Component ◽  
Vegetation Diversity ◽  
Vegetation Biomass ◽  
Relative Contribution ◽  
The Relationship

To predict the consequences of environmental change on the biodiversity of alpine wetlands, it is necessary to understand the relationship between soil properties and vegetation biodiversity. In this study, we investigated spatial patterns of aboveground vegetation biomass, cover, species diversity, and their relationships with soil properties in the alpine wetlands of the Gannan Tibetan Autonomous Prefecture of on the Qinghai-Tibetan Plateau, China. Furthermore, the relative contribution of soil properties to vegetation biomass, cover, and species diversity were compared using principal component analysis and multiple regression analysis. Generally, the relationship between plant biomass, coverage, diversity, and soil nutrients was linear or unimodal. Soil pH, bulk density and organic carbon were also significantly correlated to plant diversity. The soil attributes differed in their relative contribution to changes in plant productivity and diversity. pH had the highest contribution to vegetation biomass and species richness, while total nitrogen was the highest contributor to vegetation cover and nitrogen–phosphorus ratio (N:P) was the highest contributor to diversity. Both vegetation productivity and diversity were closely related to soil properties, and soil pH and the N:P ratio play particularly important roles in wetland vegetation biomass, cover, and diversity.

On the Sidelines: Sex and Racial Segregation in Television Sports Broadcasting

2004 ◽  
Vol 21 (3) ◽  
pp. 322-341 ◽  
Author(s):  
Barbara Thomas Coventry
Keyword(s):  
Racial Segregation ◽  
Linear Analysis ◽  
People Of Color ◽  
Social Closure ◽  
Explanatory Variables ◽  
The Social ◽  
Competition Level ◽  
Log Linear ◽  
Sports Broadcasting ◽  
The Relationship

This study explores sex and racial segregation within television sports broadcasting. It uses logit log-linear analysis to examine the relationship between job classifications within sports broadcasting and such explanatory variables as sex and race. The results show that women are concentrated in competition-level reporting and reporting but are underrepresented as studio analysts and play-by-play announcers. People of color are most likely to be found doing competition-level reporting, followed by studio analysis. They are least likely to work as play-by-play announcers. In addition, people of color are virtually limited to broadcasting baseball, basketball, and football. Although Whites also cover these three sports, they occupy practically all of the jobs covering other sports. The findings regarding sex and race support the social closure perspective that argues that women and people of color would be concentrated in lower positions within an occupation.

scholarly journals Impacts of conservation tillage on the hydrological and agronomic performance of <i>Fanya juus</i> in the upper Blue Nile (Abbay) river basin

2012 ◽  
Vol 16 (12) ◽  
pp. 4725-4735 ◽  
Author(s):  
M. Temesgen ◽  
S. Uhlenbrook ◽  
B. Simane ◽  
P. van der Zaag ◽  
Y. Mohamed ◽  
...  
Keyword(s):  
River Basin ◽  
Crop Yield ◽  
Surface Runoff ◽  
Conservation Tillage ◽  
Eragrostis Tef ◽  
Yield Reduction ◽  
Runoff Water ◽  
Blue Nile ◽  
High Rainfall ◽  
Water Logging

Abstract. Adoption of soil conservation structures (SCS) has been low in high rainfall areas of Ethiopia mainly due to crop yield reduction, increased soil erosion following breaching of SCS, incompatibility with the tradition of cross plowing and water-logging behind SCS. A new type of conservation tillage (CT) involving contour plowing and the construction of invisible subsoil barriers using a modified Maresha winged "subsoiler" is suggested as a means to tackle these problems as an integral part of the SCS. We investigated the effect of integrating the CT with SCS on the surface runoff, water-logging, soil loss, crop yield and plowing convenience. The new approach of conservation tillage has been compared with traditional tillage (TT) on 5 farmers' fields in a high rainfall area in the upper Blue Nile (Abbay) river basin. Test crops were wheat [triticum vulgare] and tef [eragrostis tef]. Farmers found CT convenient to apply between SCS. Surface runoff appeared to be reduced under CT by 48 and 15%, for wheat and tef, respectively. As a result, CT reduced sediment yield by 51 and 9.5%, for wheat and tef, respectively. Significantly reduced water-logging was observed behind SCS in CT compared to TT. Grain yields of wheat and tef increased by 35 and 10%, respectively, although the differences were not statistically significant apparently due to high fertility variations among fields of participating farmers. Farmers who tested CT indicated that they will continue this practice in the future.

scholarly journals Government Size and Corruption: A Non-linear Analysis in the Case of EMCCA

2021 ◽  
Vol 12 (4) ◽  
pp. 17
Author(s):  
Assoumou Ondo ◽  
Beau Jency Owono Ondo
Keyword(s):  
Linear Relationship ◽  
Central Government ◽  
Central Africa ◽  
Linear Analysis ◽  
Government Size ◽  
Economic Community ◽  
Non Linear ◽  
The Government ◽  
The Impact ◽  
The Relationship

This article analyzes the relationship between Government size and corruption. Unlike the works in the way which suppose a linear relationship between the two variables, we estimate a panel with change of the modes to characterize the impact of the size of the Central Government on corruption, in the countries of the economic community and monetary of Central Africa (EMCCA). The results show that there is a non-linear relationship between these two variables. Indeed, a strong involvement of the Government in economic activity results in a significant increase in corruption when the Government exceeds a size of 13.5508% of the GDP.

Effect of Velocity Profile on the Stability of Liquid Sheet

2014 ◽  
Vol 694 ◽  
pp. 288-291
Author(s):  
Run Ze Duan ◽  
Zhi Ying Chen ◽  
Li Jun Yang
Keyword(s):  
Growth Rate ◽  
Velocity Profile ◽  
Linear Analysis ◽  
Liquid Sheet ◽  
Wave Number ◽  
Flat Plates ◽  
Chebyshev Spectral Collocation ◽  
The Stability ◽  
The Relationship ◽  
Temporal Growth Rate

An electrified liquid sheet injected into a dielectric moving through a viscous gas bounded by two horizontal parallel flat plates of a transverse electric field is investigated with the linear analysis method. The liquid sheet velocity profile and the gas boundary layer thickness are taken into account. The relationship between temporal growth rate and the wave number was obtained using linear stability analysis and solved using the Chebyshev spectral collocation method. The effects of the velocity profile on the stability of the electrified liquid sheet were revealed for both sinuous mode and varicose mode. The results show that the growth rate of the electrified Newtonian liquid is greater than that of corresponding Newtonian one under the same condition, and the growth rate of the sinuous mode is greater than that of the varicose mode. Keywords: instability; planar liquid sheet; velocity profile;spectral method;linear analysis

Modelling Daily Surface Runoff, Sediment and Nutrient Loss at Watershed Scale Employing APEX Model Interfaced with GIS – A Case Study in Himalayan Landscape

2021 ◽  
Author(s):  
Suresh Kumar ◽  
Ravinder Pal Singh ◽  
Justin George Kalambukattu
Keyword(s):  
Surface Runoff ◽  
Nutrient Loss ◽  
Total Carbon ◽  
Watershed Scale ◽  
Rainfall Events ◽  
High Rainfall ◽  
Sediment Routing ◽  
Sediment Loss ◽  
Runoff Sediment ◽  
Apex Model

Abstract Daily surface runoff, sediment and nutrient loss data collected from a watershed located in Uttarakhand state of Indian Himalayan region, in year 2010-2011 and of which half of the events data were used for calibration and remaining for validation. Model was calibrated for surface runoff, sediment loss and nutrient loss to optimize the input given to the model to predict the sediment loss, erosion and nutrient loss. The calibration was done by changing the sensitive parameters. Analysis showed that SCS CN number was found most sensitive to runoff, followed by saturated hydraulic conductivity, available water-holding capacity, CN retention parameter and C factor whereas erosion control practice (P) factor was found to be most sensitive, followed by C factor, sediment routing coefficient, average upland slope and soil erodibility (K) factor for the sediment and nutrient loss. APEX model calibrated for the watershed and it predicted quite well for the surface runoff (r=0.92, NSE=0.50), sediment loss (r=0.88, NSE=0.61 and nutrients of total carbon (r=0.78, NSE=0.59) and fairly for total nitrogen (r=0.77, NSE=0.19). Surface runoff was predicted well for low and medium rainfall; however, it was over predicted for high rainfall events. Over prediction may be attributed to the unaccountable conservation measures and practices which were not accounted by the model. Similarly, sediment loss was estimated on daily basis at the watershed scale and was well predicted for low and medium rainfalls but under-estimated for high rainfall events. The area is prone to landslips occurred at high rainfall events was not accounted by the model that may be a reason for under prediction of sediment loss by the model.

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