scholarly journals Impact of soil erosion on production in cropping systems .I. Development and validation of a simulation model

Soil Research ◽  
1992 ◽  
Vol 30 (5) ◽  
pp. 757 ◽  
Author(s):  
M Littleboy ◽  
DM Silburn ◽  
DM Freebairn ◽  
DR Woodruff ◽  
GL Hammer ◽  
...  
Keyword(s):  
Soil Erosion ◽  
Simulation Model ◽  
Crop Production ◽  
Climatic Variability ◽  
Crop Growth ◽  
Potential Range ◽  
Computer Simulation Model ◽  
Small Catchment ◽  
The Impact

A computer simulation model to analyse risks of soil erosion to long-term crop production is described. The model, called PERFECT, simulates interactions between soil type, climate, fallow management strategy and crop sequence. It contains six main modules; data input, water balance, crop growth, crop residue, erosion and model output. Modules are arranged in a framework that allows alternative modules to be used as required for the potential range of applications. The model contains dynamic crop growth models for wheat, sorghum and sunflower. Validation of PERFECT against small catchment and contour bay data collected throughout Queensland showed that PERFECT explained up to 84% of the variation in total available soil water, 89% of the variation in daily runoff, and up to 75% of the variation in grain yield. Average annual soil erosion was accurately predicted but daily erosion totals were less accurate due to the exclusion of rainfall intensity in erosion prediction. Variability in climate dominates agricultural production in the subtropical region of Australia. The validated model can be coupled with long-term climate and soils databases to simulate probabilities of production and erosion risks due to climatic variability. It provides a method to determine the impact of soil erosion on long-term productivity.

scholarly journals Soil management and production of alfisols in the semi-arid tropics. IV.* Simulation of decline in productivity caused by soil erosion

Soil Research ◽  
1996 ◽  
Vol 34 (1) ◽  
pp. 127 ◽  
Author(s):  
M Littleboy ◽  
AL Cogle ◽  
GD Smith ◽  
KPC Rao ◽  
DF Yule
Keyword(s):  
Soil Erosion ◽  
Crop Production ◽  
Management Practices ◽  
Soil Depth ◽  
Management Options ◽  
Yield Decline ◽  
Initial Soil ◽  
The Impact ◽  
Semi Arid

Maintenance of a productive soil base by minimizing soil erosion is vital to long-term crop production. In this study, a modelling approach is used to estimate the effects of soil erosion on productivity for a sorghum cropping system on an Alfisol in the semi-arid tropics of India. Predictions of erosion, runoff and yield decline due to erosion, for variations in initial soil depth, slope, tillage strategy and amendment treatment, are presented. On average, soil depth decreased by 0.91 cm/year at Hyderabad for a 10% slope, 80 cm initial soil depth, shallow tillage at planting and no surface amendment. Rates of soil removal and subsequent yield decline were higher for shallower soils, steeper slopes and if management practices provided less surface cover during the crop. The productive life of the soil was less than 91 years for some soil depths, slope and management combinations. For other combinations, significant yield decline was predicted after 91 years of cropping. The quantification of erosion-productivity relationships allows us to identify regions with a higher risk of degradation from soil erosion and to estimate the impact of various management options on long-term sustainability. Models provide a basis to focus research and a means of assessing alternative management strategies to preserve long-term production.* Part III, Aust. J. Soil Res. 1996, 34, 113–125.

scholarly journals Climate change and drought effects on rural income distribution in the Mediterranean: a case study for Spain

2015 ◽  
Vol 3 (7) ◽  
pp. 4353-4389
Author(s):  
S. Quiroga ◽  
C. Suárez
Keyword(s):  
Climate Change ◽  
Income Distribution ◽  
Rural Areas ◽  
Crop Production ◽  
Crop Productivity ◽  
Social Aspect ◽  
Adaptation Measures ◽  
Effects Of Drought ◽  
The Impact

Abstract. This paper examines the effects of climate change and drought on agricultural outputs in Spanish rural areas. By now the effects of drought as a response to climate change or policy restrictions have been analyzed through response functions considering direct effects on crop productivity and incomes. These changes also affect incomes distribution in the region and therefore modify the social structure. Here we consider this complementary indirect effect on social distribution of incomes which is essential in the long term. We estimate crop production functions for a range of Mediterranean crops in Spain and we use a decomposition of inequalities measure to estimate the impact of climate change and drought on yield disparities. This social aspect is important for climate change policies since it can be determinant for the public acceptance of certain adaptation measures in a context of drought. We provide the empirical estimations for the marginal effects of the two considered impacts: farms' income average and social income distribution. In our estimates we consider crop productivity response to both bio-physical and socio-economic aspects to analyze long term implications on both competitiveness and social disparities. We find disparities in the adaptation priorities depending on the crop and the region analyzed.

Manipulation of fishing effort in Australia's penaeid Prawn Fisheries

1990 ◽  
Vol 41 (1) ◽  
pp. 1 ◽  
Author(s):  
IF Somers
Keyword(s):  
Side Effects ◽  
Great Barrier Reef ◽  
Simulation Model ◽  
Fishing Effort ◽  
Regulatory Mechanisms ◽  
Barrier Reef ◽  
Restrictive Measures ◽  
The Impact ◽  
Term Management

The potentially detrimental side-effects of prawn trawling are coming under increasing scrutiny in Australian waters, particularly in such ecologically sensitive areas as Queensland's Great Barrier Reef, and various restrictive measures are being suggested. Before changes are imposed on the prawning industry, the effects of trawling on the target prawn species and the long-term management of these effects need to be fully understood. Using a simulation model of a simplified prawn fishery, this paper describes the basis for the current regulatory mechanisms for Australian's prawn fisheries, in particular the manipulation of both the level and pattern of fishing effort. It is shown that even in moderately fished stocks, the fishery manager has several options, such as seasonal and nursery area closures, that are consistent with the goal of minimizing the impact of prawn trawling, while in no way penalizing the industry economically. With these in mind, possible ways of resolving or reducing the conflict with groups outside the prawning industry are discussed.

Patterns in data of extreme droughts/floods and harvest grades derived from historical documents in eastern China during 801–1910

2020 ◽  
Author(s):  
Zhixin Hao
Keyword(s):  
Crop Production ◽  
Eastern China ◽  
Regional Scale ◽  
Extreme Drought ◽  
Historical Documents ◽  
The North ◽  
Historical Factors ◽  
Extreme Flood ◽  
The Impact

<p>In China, historical documents record a large quantity of information related to climate change and grain harvest. This information can help to explore the impacts of extreme drought or flood on crop production, which can provide implications for the adaptation of agriculture to higher-probability extreme climate in the context of global warming. In this paper, reported extreme drought/flood chronologies and reconstructed grain harvest series derived from historical documents were adopted in order to investigate the association between the reported frequency of extreme drought/flood in eastern China and reconstructed poor harvests during 801–1910. The results show that extreme droughts were reported more often in 801–870, 1031–1230, 1481–1530, and 1581–1650 over the whole of eastern China. On a regional scale, extreme droughts were reported more often in 1031–1100, 1441–1490, 1601–1650, and 1831–1880 in the North China Plain, 801–870, 1031–1120, 1161–1220, and 1471–1530 in Jianghuai, and 991–1040, 1091–1150, 1171–1230, 1411–1470, and 1481–1530 in Jiangnan. The grain harvest was reconstructed to be generally poor in 801–940, 1251–1650, and 1841–1910, but the reconstructed harvests were bumper in 951–1250 and 1651–1840, approximately. During the entire period from 801 to 1910, the frequency of reporting of extreme droughts in any subregion of eastern China was significantly associated over the long term with lower reconstructed harvests. The association between reported frequency of extreme floods and reconstructed low harvests appeared to be much weaker, while reconstructed harvest was much worse when extreme drought and extreme flood in different subregions were reported in the same year. The association between reconstructed poor harvests and reported frequency of regional extreme droughts was weak during the warm epoch of 920–1300 but strong during the cold epoch of 1310–1880, which could imply that a warm climate could weaken the impact of extreme drought on poor harvests; yet other historical factors may also contribute to these different patterns extracted from the two datasets.</p>

scholarly journals Reducing delays in the diagnosis and treatment of muscle-invasive bladder cancer using simulation modelling

2018 ◽  
Vol 12 (2) ◽  
pp. 129-133 ◽  
Author(s):  
Daniel Chalk ◽  
Neil Trent ◽  
Sarath Vennam ◽  
John McGrane ◽  
Mark Mantle
Keyword(s):  
Bladder Cancer ◽  
Simulation Model ◽  
Bladder Tumour ◽  
Diagnosis And Treatment ◽  
Invasive Bladder Cancer ◽  
Computer Simulation Model ◽  
Nurse Specialist ◽  
Muscle Invasive Bladder Cancer ◽  
Muscle Invasive ◽  
The Impact

Objective: To develop a simulation model to identify key bottlenecks in the bladder cancer pathway at Royal Cornwall Hospital and predict the impact of potential changes to reduce these delays. Materials and methods: The diagnosis and treatment of muscle-invasive bladder cancer can suffer numerous delays, which can significantly affect patient outcomes. We developed a discrete event computer simulation model of the flow of patients through the bladder cancer pathway at the hospital, using anonymised patient records from 2014 and 2015. The changes tested in the model were for patients suspected to have muscle-invasive disease on flexible cystoscopy. Those patients were ‘fast-tracked’ to receive their transurethral resection of bladder tumour (TURBT) treatment using operating slots kept free for these patients. A staging computed tomography scan was booked in the haematuria clinic. Pathology requests were marked as 48 hour turnaround. The nurse specialist would then speak to the patient whilst they were on the ward following their TURBT to give information about their ongoing treatment and provide support. Results: The model predicted that if the changes were implemented, delays in the system could be reduced by around 5 weeks. The changes were implemented, and analysis of 3 months of the data post-implementation shows that the average time in the system was reduced by 5 weeks. The environment created by the changes in the pathway improved referral to treatment times in both muscle-invasive and non-muscle-invasive groups. Conclusion: The simulation model proved an invaluable tool for facilitating the implementation of changes. Simple changes to the pathway led to significant reductions in delays for bladder cancer patients at Royal Cornwall Hospital. Level of evidence: Not applicable for this cohort study.

scholarly journals Trends of weather-related impacts on Austrian crop production under changing climate

2021 ◽  
Author(s):  
Sabina Thaler ◽  
Josef Eitzinger ◽  
Gerhard Kubu
Keyword(s):  
Climate Change ◽  
Winter Wheat ◽  
Crop Production ◽  
Crop Yields ◽  
Weather Conditions ◽  
Crop Growth ◽  
Risk Indicators ◽  
Climate Scenarios ◽  
Crop Water

<p>Weather-related risks can affect crop growth and yield potentials directly (e.g. heat, frost, drought) and indirectly (e.g. through biotic factors such as pests). Due to climate change, severe shifts of cropping risks may occur, where farmers need to adapt effectively and in time to increase the resilience of existing cropping systems. For example, since the early 21st century, Europe has experienced a series of exceptionally dry and warmer than usual weather conditions (2003, 2012, 2013, 2015, 2018) which led to severe droughts with devastating impacts in agriculture on crop yields and pasture productivity.</p><p>Austria has experienced above-average warming in the period since 1880. While the global average surface temperature has increased by almost 1°C, the warming in Austria during this period was nearly 2°C. Higher temperatures, changing precipitation patterns and more severe and frequent extreme weather events will significantly affect weather-sensitive sectors, especially agriculture. Therefore, the development of sound adaptation and mitigation strategies towards a "climate-intelligent agriculture" is crucial to improve the resilience of agricultural systems to climate change and increased climate variability. Within the project AGROFORECAST a set of weather-related risk indicators and tailored recommendations for optimizing crop management options are developed and tested for various forecast or prediction lead times (short term management: 10 days - 6 months; long term strategic planning: climate scenarios) to better inform farmers of upcoming weather and climate challenges.</p><p>Here we present trends of various types of long-term weather-related impacts on Austrian crop production under past (1980-2020) and future periods (2035-2065). For that purpose, agro-climatic risk indicators and crop production indicators are determined in selected case study regions with the help of models. We use for the past period Austrian gridded weather data set (INCA) as well as different regionalized climate scenarios of the Austrian Climate Change Projections ÖKS15. The calculation of the agro-climatic indicators is carried out by the existing AGRICLIM model and the GIS-based ARIS software, which was developed for estimating the impact of adverse weather conditions on crops. The crop growth model AQUACROP is used for analysing soil-crop water balance parameters, crop yields and future crop water demand.</p><p>Depending on the climatic region, a more or less clear shift in the various agro-climatic indices can be expected towards 2050, e.g. the number of "heat-stress-days" for winter wheat increases significantly in eastern Austria. Furthermore, a decreasing trend in maize yield is simulated, whereas a mean increase in yield of spring barley and winter wheat can be expected under selected scenarios. Other agro-climatic risk indicators analysed include pest algorithms, risks from frost occurrence, overwintering conditions, climatic crop growing conditions, field workability and others, which can add additional impacts on crop yield variability, not considered by crop models.</p>

scholarly journals Assimilating phenology datasets automatically across ICOS ecosystem stations

2018 ◽  
Vol 32 (4) ◽  
pp. 677-687 ◽  
Author(s):  
Koen Hufkens ◽  
Gianluca Filippa ◽  
Edoardo Cremonese ◽  
Mirco Migliavacca ◽  
Petra D’Odorico ◽  
...  
Keyword(s):  
Strong Influence ◽  
Climatic Variability ◽  
Canopy Structure ◽  
Observation System ◽  
Digital Cameras ◽  
Leaf Elongation ◽  
Plant Canopies ◽  
Leaf Physiology ◽  
The Impact

Abstract The presence or absence of leaves within plant canopies exert a strong influence on the carbon, water and energy balance of ecosystems. Identifying key changes in the timing of leaf elongation and senescence during the year can help to understand the sensitivity of different plant functional types to changes in temperature. When recorded over many years these data can provide information on the response of ecosystems to long-term changes in climate. The installation of digital cameras that take images at regular intervals of plant canopies across the Integrated Carbon Observation System ecosystem stations will provide a reliable and important record of variations in canopy state, colour and the timing of key phenological events. Here, we detail the procedure for the implementation of cameras on Integrated Carbon Observation System flux towers and how these images will help us understand the impact of leaf phenology and ecosystem function, distinguish changes in canopy structure from leaf physiology and at larger scales will assist in the validation of (future) remote sensing products. These data will help us improve the representation of phenological responses to climatic variability across Integrated Carbon Observation System stations and the terrestrial biosphere through the improvement of model algorithms and the provision of validation datasets.

scholarly journals SUSTAINABLE AGRICULTURE MANAGEMENTS TO CONTROL SOIL EROSION

2021 ◽  
Author(s):  
Artemi Cerdà ◽  
Enric Terol
Keyword(s):  
Soil Erosion ◽  
Sustainable Agriculture ◽  
Spatial Scales ◽  
Low Frequency ◽  
Traditional Management ◽  
Erosion Rates ◽  
Olive Groves ◽  
Simulated Rain ◽  
The Impact

High rates of soil erosion compromise sustainable agriculture. In rainfed agricultural fields, erosion rates several orders ofmagnitude higher than the erosion rates considered tolerable have been quantified. In Mediterranean rainfed crops suchas vineyards, almonds and olive groves, and in the new sloping citrus and persimmon plantations, the rates of soil lossmake it necessary to apply measures to reduce them to avoid collapse in agricultural production. Managements such asweeds, catch crops and mulches (straw and pruning remains) are viable options to achieve sustainability. This work appliesmeasurements through plots, simulated rainfall experiments and ISUM (Improved Stock-Unearhing method) to quantifythe loss of soil at different temporal and spatial scales in fields of traditional management (herbicide or tillage) and underalternative management (mulches and plant covers). The work carried out at the experimental station for the study of soilerosion in the Sierra de Enguera and those of Montesa and Les Alcusses provide information on erosion plots undernatural rain. Experiments carried out with simulated rain in fields of olive, almond, citrus, persimmon, vineyard and fruittrees report the hydrological and erosive response under low frequency and high intensity rains. And finally, the ISUMtopographic method report the impact of long-term management, from the plantation. The results indicate that the loss ofsoil is greater (x10-1000) in soils under traditional management (tillage and herbicide) due to the fact that they remain barefor most of the year. The use of straw mulch immediately reduces soil erosion by two orders of magnitude. Also mulchesfrom chipped pruned branches remains are very efficient but require more years to reduce soil loss. Weeds and catchcrops are very efficient in controlling erosion.

scholarly journals Competency Improvement Needs of Farmers in Afforestation for Preventing and Controlling Soil Erosion in Kogi State, Nigeria

2020 ◽  
pp. 37-45
Author(s):  
Abu Mohammed ◽  
Ogbonnaya Elom ◽  
Ogechukwu Onah ◽  
Nnennaya Sinachi Monwuba
Keyword(s):  
Soil Erosion ◽  
Data Collection ◽  
Crop Production ◽  
Research Question ◽  
Sampling Technique ◽  
Agricultural Extension ◽  
Extension Agents ◽  
Significant Difference ◽  
Level Of Significance ◽  
The Impact

Farmers’ lack of awareness of agricultural activities that contribute to soil erosion and competencies needed to prevent or control the menace through afforestation contributed to unprecedented hardship, the farmers, stakeholders and individuals in Kogi state. The purpose of this study was to determine competency improvement needs farmers in pre-planting, planting and post-planting operations in afforestation and recommend for a way forward in containing the challenges. Three research question and three hypotheses guided the study. The study made use of survey research design; it was carried out in Kogi state. The population for the study was 1,244 made up of 834 registered crop farmers and 410 Agricultural Extension Agents. The sample of the study was 540. A random sampling technique (Balloting) was used to select 330 registered crop farmers out of 834 and 210 Agricultural Extension Agent out of 410 respectively. The instrument for data collection was a 49 items questionnaire titled: Competency Improvement Needs of farmers Questionnaire (CINFQ). The instrument was validated by three experts. Cronbach Alpha method was used to determine the internal consistency of the instrument and a reliability coefficient of 0.82was obtained. Five hundred and forty (540) copies of the questionnaire were administered to the respondents for data collection, but 534 copies were retrieved and analyzed. Weighted mean and Improvement Needed Index (INI) were used to answer the research questions while t-test statistics was used and test hypotheses of no significant difference at the probability of 0.05 level of significance at 532 degree of freedom. It was found out that farmers needed improvement in all the competencies in pre-planting, planting and post-planting operations for enhancing their skills in afforestation practices on their farms and that of their neighbours as a means of reducing the impact of soil erosion in the area of the study. It was recommended that the identified competencies should be used by the extension agents to re-train farmers on the practice of afforestation along with crop production and soil conservation to reduce soil erosion menace in the State.

The impact of glaciers on the long-term hydrology of a high-elevation Andean catchment

2020 ◽  
Author(s):  
Michael McCarthy ◽  
Flavia Burger ◽  
Alvaro Ayala ◽  
Stefan Fugger ◽  
Thomas E Shaw ◽  
...  
Keyword(s):  
Climatic Variability ◽  
High Elevation ◽  
Hydrological Models ◽  
Glacier Surface ◽  
Surface Mass ◽  
Extensive Field ◽  
Steep Decline ◽  
Spatio Temporal ◽  
The Impact

<p>The Andean cryosphere is a vital water resource for downstream populations. In recent years, it has been in steep decline as a whole, but shown strong spatio-temporal variability due to climatic events such as the current mega drought in central Chile. Glacio-hydrological models are necessary to understand and predict changes in water availability as a result of changes to the cryosphere. However, due to a lack of data for initialisation, forcing, calibration and validation, they are rarely used, especially in the Andes, for periods longer than a few years or decades. While useful insights can be gained from short-term modelling, there is a gap in our understanding of how glaciers impact hydrology on longer timescales, which may prevent local communities and governments from achieving effective planning and mitigation. Here we use the glacio-hydrological model TOPKAPI-ETH – initialised, forced, calibrated and validated using unique and extensive field and remote sensing datasets – to investigate glacier contributions to the streamflow of the high-elevation Rio Yeso catchment, Chile, over the past 50 years. We focus in particular on: 1) fluctuations in glacier surface mass balance and runoff and associated climatic variability; 2) if peak water has already occurred and when; 3) the effect of supraglacial debris cover on seasonal and long-term hydrographs. We offer insights into some of the challenges of running glacio-hydrological models on longer timescales and discuss the implications of our findings in the context of a shrinking Andean cryosphere.</p>

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