EFFECTS OF SOIL EROSION ON YIELD OF CORN

1978 ◽  
Vol 58 (4) ◽  
pp. 459-463 ◽  
Author(s):  
J. W. KETCHESON ◽  
L. R. WEBBER

Historically, special or intensive soil conservation methods have been recommended to control soil and water losses and maintain crop yields. However, farmers have not adopted these recommendations due to the high-energy input and the resulting reduction in high-value crop acreage. Crop yields do not appear to justify the cost of erosion control. Over a 10-yr period at Guelph, corn grown one year in a 4-yr rotation of corn, oats, hay and hay on runoff plots yielded 200–400 kg/ha above the average annual yield of corn grown continuously. Soil erosion losses averaged < 0.01 cm/yr from corn in rotation compared with 0.125 cm/yr from continuous corn. Under uniform cropping at the end of the period, corn grain yields did not reflect differences in soil erosion. In a subsequent 6-yr period, continuous corn with stover left on the soil surface and no tillage controlled soil erosion to < 0.01 cm/yr. The greatest soil and nutrient losses (0.36 cm soil, 87 kg N/ha and 59 kg P/ha/yr) occurred when stover was removed and the plots plowed in the fall. Corn grain yield was not reduced by these losses.

1998 ◽  
Vol 13 (2) ◽  
pp. 79-82 ◽  
Author(s):  
Robert J. Walle ◽  
Brian G. Sims

AbstractThe effects of contour live barriers of vetiver and pennisetum on soil erosion were studied on four small farms in south central Honduras. Paired plots were installed and soil erosion measured by changes in the soil surface level of transects 0.3 and 6.0 m up the slope from the barrier. After three years, transects 0.3 m above the barriers significantly retained eroded soil compared with control transects. Soil accumulation by barriers ranged from 2.6 to 11.2 cm, and natural terrace formation (the difference between the barrier and corresponding control transect) ranged from 5.2 to 13.8 cm. No difference was detected between barrier and control for the transects 6.0 m above the barrier. Deposition in front of the barriers and reduction in surface rilling were apparent to farmers. Erosion from up slope on the barrier plots and from both transects in the control sections was not obvious. Direct measurement and farmer observation of sediment deposition by live barriers will help evaluate farmer-identified species for future use. The deposition helps farmers become aware of sheet erosion before the effects of soil degradation on crop yields become grossly apparent and soil fertility restoration becomes too costly for small-scale farmers.


2020 ◽  
Author(s):  
Timothy Foster ◽  
Roshan Adhikari ◽  
Subash Adhikari ◽  
Anton Urfels ◽  
Timothy Krupnik

&lt;p&gt;In many parts of South Asia, electricity for groundwater pumping has been directly or indirectly subsidised by governments to support intensification of agriculture. In contrast, farmers in large portions of the Eastern Indo-Gangetic Plains (EIGP) remain largely dependent on unsubsidised diesel or petrol power for irrigation pumping. Combined with a lack of comprehensive aquifer mapping, high energy costs of pumping limit the ability of farmers to utilise available groundwater resources. This increases exposure to farm production risks, in particular drought and precipitation variability.&lt;/p&gt;&lt;p&gt;To date, research to address these challenges has largely focused on efforts to enhance rural electrification or introduce renewable energy-based pumping systems that remain out of reach of many poor smallholders. However, there has been comparatively little focus on understanding opportunities to improve the cost-effectiveness and performance of the thousands of existing diesel-pump irrigation systems already in use in the EIGP. Here, we present findings from a recent survey of over 432 farmer households in the mid-western Terai region of Nepal &amp;#8211; an important area of diesel-pump irrigation in the EIGP. Our survey provides information about key socio-economic, technological and behavioral aspects of diesel pump irrigation systems currently in operation, along with quantitative evidence about their impacts on agricultural productivity and profitability.&lt;/p&gt;&lt;p&gt;Survey results indicate that groundwater irrigation costs vary significantly between individual farmers. Farmers faced with higher costs of groundwater access irrigate their crops less frequently, which in turn results in lower crop yields and reduced overall farm profitability. Our data indicate that pumpset fuel efficiency may be a key driver of variability in irrigation costs, with large horsepower (&gt;5 HP) Indian-made pumpsets appearing to have significantly higher fuel consumption rates (1.10 litre/hour and $18,000) and investments costs than alternative smaller horsepower (&lt;5 HP) Chinese-made pumpsets (0.76 litre/hr and $30,000). Despite this, the majority of farmers continue to favour Indian pumpsets due to their higher reliability and well-established supply chains. Variability in access costs is also related to differences in capacity of farmers to invest in their own pumping systems. Pumpset rental rates in the region increase irrigation costs by a factor of 3-4 relative to the cost of fuel alone. Furthermore, rental rates typically are structured on a per-hourly basis, further exacerbating access costs for farmers with low yielding wells or whose irrigation management practices are less efficient.&lt;/p&gt;&lt;p&gt;Our findings highlight that opportunities exist to reduce costs of groundwater use in existing diesel irrigation systems through improved access to more energy efficient pumping systems. This would have positive near-term impacts on agricultural productivity and rural livelihoods, in particular helping farmers to more effectively buffer crops against monsoonal variability. Such near-term improvements in diesel pump irrigation systems would also play an important role in supporting agriculture in the EIGP to transition to more sustainable and clean sources of energy for irrigation pumping. However, efforts to enhance irrigation access must also occur alongside improvements to aquifer monitoring and governance of extraction, in order to minimise risks of future depletion such as observed in other parts of the IGP.&lt;/p&gt;


Author(s):  
Igor Kupchuk

Feed make up a large part of the cost for livestock production and determine its quality. A very important technological operation with high energy costs is the grinding of feed grain (wheat, barley, peas, corn, etc.). Therefore, research on the development of effective technologies and cost-effective equipment for grinding is relevant and of practical value. In the laboratory of the theory of mechanisms and machines of the department of general technical disciplines and labor protection of Vinnitsa National Agrarian University, a vibratory disk crusher was designed to increase the level of technical support for the livestock industry. The crusher uses a more efficient method of grinding feed grain - a combination of impact and cutting, in contrast to a hammer mill that grinds with a free impact of hammers. The research results of grinding corn grain into feed by a vibratory disk crusher are presented in the article. An experimental prototype of the developed machine was used as an object of research. To register the input and output parameters of grinding, we used the material and technical base of the department of technological processes and equipment of processing and food industries. In order to comply with the zootechnical requirements for the degree of grinding of grain into feed, the dispersion of the obtained product was also controlled. The sizes of the fractions were determined by mechanical separation on a sieve analyzer. Data processing was carried out in the Microsoft Excel software package. Thus, graphs were obtained and rational parameters of the vibratory disk crusher were determined. This was done by analyzing the performance for the crusher depending on the rotor angular velocity, the sieve perforation diameter and the grain moisture content.


Phlebologie ◽  
2007 ◽  
Vol 36 (06) ◽  
pp. 309-312 ◽  
Author(s):  
T. Schulz ◽  
M. Jünger ◽  
M. Hahn

Summary Objective: The goal of the study was to assess the effectiveness and patient tolerability of single-session, sonographically guided, transcatheter foam sclerotherapy and to evaluate its economic impact. Patients, methods: We treated 20 patients with a total of 22 varicoses of the great saphenous vein (GSV) in Hach stage III-IV, clinical stage C2-C5 and a mean GSV diameter of 9 mm (range: 7 to 13 mm). We used 10 ml 3% Aethoxysklerol®. Additional varicoses of the auxiliary veins of the GSV were sclerosed immediately afterwards. Results: The occlusion rate in the treated GSVs was 100% one week after therapy as demonstrated with duplex sonography. The cost of the procedure was 207.91 E including follow-up visit, with an average loss of working time of 0.6 days. After one year one patient showed clinical signs of recurrent varicosis in the GSV; duplex sonography showed reflux in the region of the saphenofemoral junction in a total of seven patients (32% of the treated GSVs). Conclusion: Transcatheter foam sclerotherapy of the GSV is a cost-effective, safe method of treating varicoses of GSV and broadens the spectrum of therapeutic options. Relapses can be re-treated inexpensively with sclerotherapy.


2019 ◽  
Vol 2019 (4) ◽  
pp. 7-22
Author(s):  
Georges Bridel ◽  
Zdobyslaw Goraj ◽  
Lukasz Kiszkowiak ◽  
Jean-Georges Brévot ◽  
Jean-Pierre Devaux ◽  
...  

Abstract Advanced jet training still relies on old concepts and solutions that are no longer efficient when considering the current and forthcoming changes in air combat. The cost of those old solutions to develop and maintain combat pilot skills are important, adding even more constraints to the training limitations. The requirement of having a trainer aircraft able to perform also light combat aircraft operational mission is adding unnecessary complexity and cost without any real operational advantages to air combat mission training. Thanks to emerging technologies, the JANUS project will study the feasibility of a brand-new concept of agile manoeuvrable training aircraft and an integrated training system, able to provide a live, virtual and constructive environment. The JANUS concept is based on a lightweight, low-cost, high energy aircraft associated to a ground based Integrated Training System providing simulated and emulated signals, simulated and real opponents, combined with real-time feedback on pilot’s physiological characteristics: traditionally embedded sensors are replaced with emulated signals, simulated opponents are proposed to the pilot, enabling out of sight engagement. JANUS is also providing new cost effective and more realistic solutions for “Red air aircraft” missions, organised in so-called “Aggressor Squadrons”.


Author(s):  
N. Maidanovych ◽  

The purpose of this work is to review and analyze the main results of modern research on the impact of climate change on the agro-sphere of Ukraine. Results. Analysis of research has shown that the effects of climate change on the agro-sphere are already being felt today and will continue in the future. The observed climate changes in recent decades have already significantly affected the shift in the northern direction of all agro-climatic zones of Europe, including Ukraine. From the point of view of productivity of the agro-sphere of Ukraine, climate change will have both positive and negative consequences. The positives include: improving the conditions of formation and reducing the harvesting time of crop yields; the possibility of effective introduction of late varieties (hybrids), which require more thermal resources; improving the conditions for overwintering crops; increase the efficiency of fertilizer application. Model estimates of the impact of climate change on wheat yields in Ukraine mainly indicate the positive effects of global warming on yields in the medium term, but with an increase in the average annual temperature by 2 ° C above normal, grain yields are expected to decrease. The negative consequences of the impact of climate change on the agrosphere include: increased drought during the growing season; acceleration of humus decomposition in soils; deterioration of soil moisture in the southern regions; deterioration of grain quality and failure to ensure full vernalization of grain; increase in the number of pests, the spread of pathogens of plants and weeds due to favorable conditions for their overwintering; increase in wind and water erosion of the soil caused by an increase in droughts and extreme rainfall; increasing risks of freezing of winter crops due to lack of stable snow cover. Conclusions. Resource-saving agricultural technologies are of particular importance in the context of climate change. They include technologies such as no-till, strip-till, ridge-till, which make it possible to partially store and accumulate mulch on the soil surface, reduce the speed of the surface layer of air and contribute to better preservation of moisture accumulated during the autumn-winter period. And in determining the most effective ways and mechanisms to reduce weather risks for Ukrainian farmers, it is necessary to take into account the world practice of climate-smart technologies.


2018 ◽  
Author(s):  
Ricardo Guedes ◽  
Vasco Furtado ◽  
Tarcísio Pequeno ◽  
Joel Rodrigues

UNSTRUCTURED The article investigates policies for helping emergency-centre authorities for dispatching resources aimed at reducing goals such as response time, the number of unattended calls, the attending of priority calls, and the cost of displacement of vehicles. Pareto Set is shown to be the appropriated way to support the representation of policies of dispatch since it naturally fits the challenges of multi-objective optimization. By means of the concept of Pareto dominance a set with objectives may be ordered in a way that guides the dispatch of resources. Instead of manually trying to identify the best dispatching strategy, a multi-objective evolutionary algorithm coupled with an Emergency Call Simulator uncovers automatically the best approximation of the optimal Pareto Set that would be the responsible for indicating the importance of each objective and consequently the order of attendance of the calls. The scenario of validation is a big metropolis in Brazil using one-year of real data from 911 calls. Comparisons with traditional policies proposed in the literature are done as well as other innovative policies inspired from different domains as computer science and operational research. The results show that strategy of ranking the calls from a Pareto Set discovered by the evolutionary method is a good option because it has the second best (lowest) waiting time, serves almost 100% of priority calls, is the second most economical, and is the second in attendance of calls. That is to say, it is a strategy in which the four dimensions are considered without major impairment to any of them.


RSC Advances ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 5432-5443
Author(s):  
Shyam K. Pahari ◽  
Tugba Ceren Gokoglan ◽  
Benjoe Rey B. Visayas ◽  
Jennifer Woehl ◽  
James A. Golen ◽  
...  

With the cost of renewable energy near parity with fossil fuels, energy storage is paramount. We report a breakthrough on a bioinspired NRFB active-material, with greatly improved solubility, and place it in a predictive theoretical framework.


Agronomy ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 974
Author(s):  
Rafael Blanco-Sepúlveda ◽  
Amilcar Aguilar-Carrillo ◽  
Francisco Lima

In conservation agriculture, the no-tillage cultivation system and the retention of permanent vegetal cover are crucial to the control of soil erosion by water. This paper analyses the cultivation of maize under no-tillage, with particular reference to the effect produced on soil erosion when weed control is performed by a hand tool (machete), which disturbs the surface of the soil, and to the behavior of the soil cover in these circumstances. The study area is located in the humid tropical mountains of northern Nicaragua (Peñas Blancas Massif Nature Reserve). The results obtained show that 59.2% of the soil surface was affected by appreciable levels of sheet and splash erosion, although the vegetal cover of the soil was relatively high (with average weed and litter cover of 33.9% and 33.8%, respectively). The use of machetes for weed control provoked considerable soil disturbance, which explained the high rates of erosion observed. Moreover, this form of soil management disturbs the litter layer, making it less effective in preventing erosion. The litter remains loose on the soil surface, and so an increase in soil cover does not achieve a proportionate reduction in the area affected by erosion; thus, even with 80–100% weed and litter cover, 42% of the cultivated area continued to present soil erosion.


2013 ◽  
Vol 23 (2) ◽  
pp. 133-140 ◽  
Author(s):  
Xiaowen Hu ◽  
Tingshan Li ◽  
Juan Wang ◽  
Yanrong Wang ◽  
Carol C. Baskin ◽  
...  

AbstractAlthough seed dormancy of temperate legumes is well understood, less is known about it in species that grow in subalpine/alpine areas. This study investigated dormancy and germination of four Vicia species from the Tibetan Plateau. Fresh seeds of V. sativa were permeable to water, whereas those of V. angustifolia, V. amoena and V. unijuga had physical dormancy (PY). One year of dry storage increased the proportion of impermeable seeds in V. angustifolia, but showed no effect on seed coat permeability in V. amoena or V. unijuga. Seeds of all four species also had non-deep physiological dormancy (PD), which was especially apparent in the two annuals at a high germination temperature (20°C). After 1 year of storage, PD had been lost. The hydrotime model showed that fresh seeds obtained a significantly higher median water potential [Ψb(50)] than stored seeds, implying that PD prevents germination in winter for seeds dispersed without PY when water availability is limited. After 6 months on the soil surface in the field, a high proportion of permeable seeds remained ungerminated, further suggesting that PD plays a key role in preventing germination after dispersal. Addition of fluridone, an inhibitor of abscisic acid (ABA) biosynthesis, evened-out the differences in germination between fresh and stored seeds, which points to the key role of ABA biosynthesis in maintaining dormancy. Further, fresh seeds were more sensitive to exogenous ABA than stored seeds, indicating that storage decreased embryo sensitivity to ABA. On the other hand, the gibberellic acid GA3 increased germination rate, which implies that embryo sensitivity to GA is also involved in seed dormancy regulation. This study showed that PY, PD or their combination (PY+PD) plays a key role in timing germination after dispersal, and that different intensities of dormancy occur among these four Vicia species from the Tibetan Plateau.


Sign in / Sign up

Export Citation Format

Share Document