scholarly journals The Effects of Wetland Droughts on a Reserve in the African Continent

2021 ◽  
pp. 22-30
Author(s):  
Lawan Bulama ◽  
Ejeh Udeh Lawrence ◽  
Ahmad Abubakar Umar
Keyword(s):  
Migratory Birds ◽  
Management Strategies ◽  
Standardized Precipitation Index ◽  
Annual Rainfall ◽  
African Continent ◽  
Body Of Knowledge ◽  
High Magnitude ◽  
Wetland Water ◽  
Drying Up ◽  
Wintering Area

Climate change and its attendant fallouts such as drought, flood etc affect every aspects of environment including wetland ecosystem. This paper seeks to examine the effects of droughts on Dagona Waterfowl Sanctuary−an important wintering area for migratory birds in Bade local government, Yobe state, Nigeria. The study used annual rainfall data collected from the archives of the Nigerian Meteorological Agency (NIMET) with respect to Nguru weather station in the area for a period of 1956-2015. Standardized Precipitation Index (SPI) in conjunction with Percentage Deviation Below Mean (PDBM) models were applied for comprehensive drought detection on a time scale of twelve (12) months. SPI anomaly graphs were plotted to depict drought of varying magnitude. The researcher went round the sanctuary and made observations with the help of binocular and telescope. Findings explicitly revealed that the study area was replete with droughts of varying intensities ranging from mild, moderate, severe and extreme ones. And high magnitude droughts led to hydrological changes causing drying up of wetland water, decreased production of seeds that provide forage opportunities, intrusion of invasive species such as typha grasses forming dense biomass that hinder birds to prey on fishes or swim freely. The result of the analysis would add to the mainstream theoretical body of knowledge about droughts effects on wetlands. The research concludes that droughts of high magnitude occurred variably and affected both native and migratory birds in the study area and hence recommend the integration of disasters like drought in the management strategies of the wetlands.

scholarly journals Phenology of two interdependent traits in migratory birds in response to climate change

2015 ◽  
Vol 282 (1807) ◽  
pp. 20150288 ◽  
Author(s):  
Nadiah Pardede Kristensen ◽  
Jacob Johansson ◽  
Jörgen Ripa ◽  
Niclas Jonzén
Keyword(s):  
Climate Change ◽  
Resource Availability ◽  
Migratory Birds ◽  
Egg Laying ◽  
The Other ◽  
Sufficient Evidence ◽  
Hatching Date ◽  
Arrival Date ◽  
Body Of Knowledge ◽  
Asynchronous Hatching

In migratory birds, arrival date and hatching date are two key phenological markers that have responded to global warming. A body of knowledge exists relating these traits to evolutionary pressures. In this study, we formalize this knowledge into general mathematical assumptions, and use them in an ecoevolutionary model. In contrast to previous models, this study novelty accounts for both traits—arrival date and hatching date—and the interdependence between them, revealing when one, the other or both will respond to climate. For all models sharing the assumptions, the following phenological responses will occur. First, if the nestling-prey peak is late enough, hatching is synchronous with, and arrival date evolves independently of, prey phenology. Second, when resource availability constrains the length of the pre-laying period, hatching is adaptively asynchronous with prey phenology. Predictions for both traits compare well with empirical observations. In response to advancing prey phenology, arrival date may advance, remain unchanged, or even become delayed; the latter occurring when egg-laying resources are only available relatively late in the season. The model shows that asynchronous hatching and unresponsive arrival date are not sufficient evidence that phenological adaptation is constrained. The work provides a framework for exploring microevolution of interdependent phenological traits.

scholarly journals Twentieth-Century Climate Change over Africa: Seasonal Hydroclimate Trends and Sahara Desert Expansion

2018 ◽  
Vol 31 (9) ◽  
pp. 3349-3370 ◽  
Author(s):  
Natalie Thomas ◽  
Sumant Nigam
Keyword(s):  
Twentieth Century ◽  
Source Region ◽  
Surface Air Temperature ◽  
Rain Gauge ◽  
Mitigation Strategies ◽  
Annual Rainfall ◽  
Sahara Desert ◽  
Seasonal Temperature ◽  
African Continent ◽  
Climate Simulations

Twentieth-century trends in seasonal temperature and precipitation over the African continent are analyzed from observational datasets and historical climate simulations. Given the agricultural economy of the continent, a seasonal perspective is adopted as it is more pertinent than an annual-average one, which can mask offsetting but agriculturally sensitive seasonal hydroclimate variations. Examination of linear trends in seasonal surface air temperature (SAT) shows that heat stress has increased in several regions, including Sudan and northern Africa where the largest SAT trends occur in the warm season. Broadly speaking, the northern continent has warmed more than the southern one in all seasons. Precipitation trends are varied but notable declining trends are found in the countries along the Gulf of Guinea, especially in the source region of the Niger River in West Africa, and in the Congo River basin. Rainfall over the African Great Lakes—one of the largest freshwater repositories—has, however, increased. It is shown that the Sahara Desert has expanded significantly over the twentieth century, by 11%–18% depending on the season, and by 10% when defined using annual rainfall. The expansion rate is sensitively dependent on the analysis period in view of the multidecadal periods of desert expansion (including from the drying of the Sahel in the 1950s–80s) and contraction in the 1902–2013 record, and the stability of the rain gauge network. The desert expanded southward in summer, reflecting retreat of the northern edge of the Sahel rainfall belt, and to the north in winter, indicating potential impact of the widening of the tropics. Specific mechanisms for the expansion are investigated. Finally, this observational analysis is used to evaluate the state-of-the-art climate simulations from a comparison of the twentieth-century hydroclimate trends. The evaluation shows that modeling regional hydroclimate change over the African continent remains challenging, warranting caution in the development of adaptation and mitigation strategies.

scholarly journals Improving water productivity in the Australian Grains industry—a nationally coordinated approach

2014 ◽  
Vol 65 (7) ◽  
pp. 583 ◽  
Author(s):  
J. A. Kirkegaard ◽  
J. R. Hunt ◽  
T. M. McBeath ◽  
J. M. Lilley ◽  
A. Moore ◽  
...  
Keyword(s):  
Water Use ◽  
Production Systems ◽  
Water Productivity ◽  
Management Strategies ◽  
Wheat Yield ◽  
Farming Systems ◽  
Annual Rainfall ◽  
Cost Ratio ◽  
Ex Post ◽  
Farm Scale

Improving the water-limited yield of dryland crops and farming systems has been an underpinning objective of research within the Australian grains industry since the concept was defined in the 1970s. Recent slowing in productivity growth has stimulated a search for new sources of improvement, but few previous research investments have been targeted on a national scale. In 2008, the Australian grains industry established the 5-year, AU$17.6 million, Water Use Efficiency (WUE) Initiative, which challenged growers and researchers to lift WUE of grain-based production systems by 10%. Sixteen regional grower research teams distributed across southern Australia (300–700 mm annual rainfall) proposed a range of agronomic management strategies to improve water-limited productivity. A coordinating project involving a team of agronomists, plant physiologists, soil scientists and system modellers was funded to provide consistent understanding and benchmarking of water-limited yield, experimental advice and assistance, integrating system science and modelling, and to play an integration and communication role. The 16 diverse regional project activities were organised into four themes related to the type of innovation pursued (integrating break-crops, managing summer fallows, managing in-season water-use, managing variable and constraining soils), and the important interactions between these at the farm-scale were explored and emphasised. At annual meetings, the teams compared the impacts of various management strategies across different regions, and the interactions from management combinations. Simulation studies provided predictions of both a priori outcomes that were tested experimentally and extrapolation of results across sites, seasons and up to the whole-farm scale. We demonstrated experimentally that potential exists to improve water productivity at paddock scale by levels well above the 10% target by better summer weed control (37–140%), inclusion of break crops (16–83%), earlier sowing of appropriate varieties (21–33%) and matching N supply to soil type (91% on deep sands). Capturing synergies from combinations of pre- and in-crop management could increase wheat yield at farm scale by 11–47%, and significant on-farm validation and adoption of some innovations has occurred during the Initiative. An ex post economic analysis of the Initiative estimated a benefit : cost ratio of 3.7 : 1, and an internal return on investment of 18.5%. We briefly review the structure and operation of the initiative and summarise some of the key strategies that emerged to improve WUE at paddock and farm-scale.

scholarly journals Investigation of Various Diseases Occurred in Poultry and Management Strategies for Eradication

2018 ◽  
Vol 7 (3.1) ◽  
pp. 150
Author(s):  
Sunil Patil ◽  
Chhanwal I.L
Keyword(s):  
Family Income ◽  
Migratory Birds ◽  
Management Practice ◽  
Management Strategies ◽  
Farm Management ◽  
Poultry Meat ◽  
Highly Pathogenic ◽  
The World ◽  
Pathogenic Viruses ◽  
Poultry Disease

Poultry plays a significant role in the Indian economy. Around 60 billion chickens are raised per annum as a basis of food for both their eggs and meat. Poultry meat is in significant source of minerals, protein and various vitamins to balance the diet of human. Broiler farming is an important source of family income depending on size of the farm. Chicken farming in Commercial way is the most fruitful business in India and all around the world. Proper farm management practice and care of birds will result in decent profit in a short span of time. In this paper, we are discussing various diseases caused to poultry hen and their preventing or treating methods. Our results shows that some of disease cannot be cured and only it can be prevented. Spreading of disease with the help of contaminated equipment and infected poultry trade is measured as foremost means of spreading of poultry disease. In some countries migratory birds have also been foremost means of spreading of poultry disease like highly pathogenic viruses. 

Crop stubbles are as important for sheep production as annual pastures in the Victorian Mallee

2006 ◽  
Vol 46 (8) ◽  
pp. 993 ◽  
Author(s):  
S. M. Robertson
Keyword(s):  
Plant Density ◽  
Cropping Systems ◽  
Management Strategies ◽  
Simulation Modelling ◽  
Annual Rainfall ◽  
Pasture Management ◽  
Pasture Production ◽  
Eastern Australia ◽  
Sheep Production ◽  
The Impact

The impact of different management strategies on production and profit can be evaluated with knowledge of how sheep production responds to changes in the available feed base and sheep or pasture management. This study aimed to quantify on-farm pasture and sheep production in mixed sheep and cropping systems in the Victorian Mallee of south-eastern Australia (325 ± 50 mm annual rainfall) as a prelude to computer simulation modelling. During 2001 (average rainfall) and 2002 (extreme drought) pasture production, the feed base and sheep production were monitored in 15 paddocks on 5 properties located across the region. Crop stubbles were the major source of feed for 6 months of the year, enabling ewes to maintain liveweight. There was more variation in pasture parameters between paddocks at the 1 location than between locations. The botanical composition, plant density, soil fertility and management were key variables associated with between-paddock variation in pasture production. Variation in pasture production between years was larger than within-year differences. In contrast, stocking rates were not much lower in the drought year of 2002 than in 2001. This study suggests there is potential for management to improve pasture production, and demonstrates the importance of feed sources other than annual pasture for sheep production in environments where the annual pasture growing season is short.

scholarly journals Long term effect of climate change on rainfall in northwest Iraq

2014 ◽  
Vol 4 (3) ◽  
Author(s):  
Nadhir Al-Ansari ◽  
Mawada Abdellatif ◽  
Salahalddin Ali ◽  
Sven Knutsson
Keyword(s):  
Climate Change ◽  
Management Strategies ◽  
Daily Rainfall ◽  
Annual Rainfall ◽  
Water Shortages ◽  
Intergovernmental Panel ◽  
Continuous Decrease ◽  
Rainfall Trends ◽  
Semi Arid Region

AbstractMiddle East, like North Africa, is considered as arid to semi-arid region. Water shortages in this region, represents an extremely important factor in stability of the region and an integral element in its economic development and prosperity. Iraq was an exception due to presence of Tigris and Euphrates Rivers. After the 1970s the situation began to deteriorate due to continuous decrease in discharges of these rivers, are expected to dry by 2040 with the current climate change. In the present paper, long rainfall trends up to the year 2099 were studied in Sinjar area, northwest of Iraq, to give an idea about its future prospects. Two emission scenarios, used by the Intergovernmental Panel on Climate Change (A2 and B2), were employed to study the long term rainfall trends in northwestern Iraq. All seasons consistently project a drop in daily rainfall for all future periods with the summer season is expected to have more reduction compared to other seasons. Generally the average rainfall trend shows a continuous decrease. The overall average annual rainfall is slightly above 210 mm. In view of these results, prudent water management strategies have to be adopted to overcome or mitigate consequences of future severe water crisis.

Current Practices in the Management of Postoperative Arterial Vasospasm in Microsurgery

2017 ◽  
Vol 34 (04) ◽  
pp. 242-249 ◽  
Author(s):  
Sergey Turin ◽  
Robert Walton ◽  
Gregory Dumanian ◽  
John Hijjawi ◽  
John LoGiudice ◽  
...  
Keyword(s):  
Lower Limb ◽  
Management Strategies ◽  
Superior Thyroid Artery ◽  
Recipient Vessel ◽  
Root Cause ◽  
Body Of Knowledge ◽  
Epigastric Artery ◽  
Arterial Vasospasm ◽  
Reconstructive Microsurgery ◽  
American Society

Background Postoperative microvascular arterial vasospasm is a rare clinical entity. There are no published management algorithms and also the pathophysiology of this phenomenon has not been elucidated. Methods An email survey of American Society for Reconstructive Microsurgery (ASRM) and World Society for Reconstructive Microsurgery (WSRM) members regarding their experiences with postoperative arterial vasospasm was conducted, returning 116 responses. A comprehensive literature search was conducted regarding the current body of knowledge on this entity. Results Sixty-five percent of respondents encountered cases where postoperative arterial vasospasm was clearly the cause of flap ischemia. The majority (62%) of surgeons believed a damaged segment of the artery was responsible for the spasm, with technical issues cited as the most likely cause. Sixty-two percent and 50% of surgeons used segmental resection of the recipient and donor vessels, respectively.Rated for proclivity to vasospasm, superficial inferior epigastric artery (SIEA) was the flap, superior thyroid artery (STA) the recipient vessel, and the lower limb the anatomic region most frequently mentioned.Most widely used management strategies were: topical vasodilators (91%), adventitial stripping (82%), and dilation of recipient and donor vessels (76%). Over 50% of surgeons used some type of vessel resection technique. Conclusions When flap ischemia is encountered without mechanical issues or thrombus, vasospasm can be the root cause. Certain vessels (SIEA, STA) and anatomic regions (lower limb) pose a higher risk for this phenomenon. When a vessel is affected, it is common practice to excise the questionable segment and use a graft as needed. Vessel resection as part of a multimodal approach can result in a reasonable salvage rate.

scholarly journals Vulnerability of Calabar Rainfall to Climatic Variability Events: A Critical Factor in Integrated Water Resources Management in the Tropical Coastal Location in Southeastern Nigeria

2021 ◽  
Vol 16 (1) ◽  
pp. 115-122
Author(s):  
Solomon O. Amadi ◽  
Mfongang E. Agbor ◽  
Sunday O. Udo
Keyword(s):  
Water Resources ◽  
Water Resources Management ◽  
Rainfall Variability ◽  
Climatic Variability ◽  
Standardized Precipitation Index ◽  
Annual Rainfall ◽  
Least Squares Regression ◽  
Southeastern Nigeria ◽  
Resources Management ◽  
Dry Spell

In this study, Calabar annual total rainfall was analysed for trend and climatic variability events with focus on drought occurrence. Monthly rainfall data from in situ measurements over a 41 year period (1972-2012) were used for the study. Standard tests were used to evaluate the trends and variability in annual rainfall. Rainfall variability was estimated as standardized rainfall departures and used to identify and delimitate the dry and wet spell sequences of Calabar rainfall. The rainfall series were analysed for Standardized Precipitation Index (SPI) using SPSS Version 17 software. The least squares regression plot was executed using Excel 2010 to depict the trend, variability and regression parameters. The average annual rainfall for Calabar is 2984.64 mm with standard deviation of 394.9 mm. 36.59% of the period showed positive SPI while 63.41 % of the period indicated negative SPI values. Wet spell dominated the later part of the period but sandwiched with dry spells whereas dry spell were dominant from 1972 to 1994. The area experienced a non-significant upward trend of 15.21 mm per year over the interval. The SPI values indicate that Calabar experienced distinct inter-annual rainfall cycles that represent mild to extreme droughts and wet spells which are a demonstration of consequential annual rainfall variability. The results underscore the need for effective monitoring of Calabar rainfall for prompt warnings and responses that would guarantee effective risk reduction and management in the run-in to the occurrence of the extreme events. The paper further highlights the need for data-driven approach to policy making in water resources management. This would provide a fascinating insight into the improvement in long-term water resources management in the city and its suburbs.

scholarly journals Spatio-temporal variability of climatic parameters across different altitudes of North- Western Himalaya

2021 ◽  
Vol 21 (3) ◽  
pp. 297-306
Author(s):  
PANKAJ PANWAR ◽  
SHARMISTHA PAL ◽  
NANCY LORIA ◽  
MED RAM VERMA ◽  
N.M. ALAM ◽  
...  
Keyword(s):  
Rainfall Variability ◽  
Management Strategies ◽  
Extreme Rainfall ◽  
Western Himalaya ◽  
Farming System ◽  
Annual Rainfall ◽  
Maximum Temperature ◽  
Rainfall Occurrence ◽  
Spatio Temporal ◽  
Different Altitudes

Climate change impact varies across different altitudinal ranges and demands local specific management strategies for water resource and farming system management. The present study analyses spacio-temporal climate parameters across different altitudes of Himachal Pradesh a hilly state of India. Analysis shows that annually, minimum temperature has significantly decreased by -0.09°C at altitude I (350 - 400 m) while maximum temperature has significantly increased by 0.05°C at altitudes I and II (1400-1500 m) and decreased significantly by -0.08°C at altitude III (2000- 2100 m). Higher regions Altitude – IV (2900-3000 m) received lowest rainfall (746.1 mm) with 30.2 % variation. Seasonal rainfall variability was higher in post monsoon (102 - 174%) and least in monsoon (21 - 57%). Annual rainfall at altitude I is strongly irregular (PCI 20.1 to 22.3), followed by altitude – IV (PCI 15-25); altitude – II irregular (PCI 15-20) and altitude – III moderate to irregular (PCI 12 -19) rainfall. Seasonal Index values for four altitudes fall between 0.91-0.96 revealed that rainfall is irregular and markedly seasonal with longer drier season. Higher wavelet powers in altitude - I and II after 2005 suggests frequency of extreme rainfall occurrence had increased.

scholarly journals Hydro-Climatic Variability: A Characterisation and Trend Study of the Awash River Basin, Ethiopia

Hydrology ◽  
2019 ◽  
Vol 6 (2) ◽  
pp. 35 ◽  
Author(s):  
Mahtsente Tibebe Tadese ◽  
Lalit Kumar ◽  
Richard Koech ◽  
Birhanu Zemadim
Keyword(s):  
River Basin ◽  
Climatic Variability ◽  
Management Strategies ◽  
Annual Rainfall ◽  
Sustainable Water Management ◽  
Mk Test ◽  
Awash River Basin ◽  
Research Findings ◽  
Droughts And Floods ◽  
The Impact

The objective of this study was to characterize, quantify and validate the variability and trends of hydro-climatic variables in the Awash River Basin (ARB) in Ethiopia using graphical and statistical methods. The rainfall and streamflow trends and their relationships were evaluated using the regression method, Mann–Kendall (MK) test and correlation analysis. The analysis focused on rainfall and streamflow collected from 28 and 18 stations, respectively. About 85.7% and 75.3% of the rainfall stations exhibited normal to moderate variability in annual and June to September rainfall, respectively, whereas 96.43% of rainfall stations showed high variability in March to May. The MK test showed that most of the significant trends in annual rainfall were decreasing except in two stations. These research findings provide valuable information on the characteristics, variability, and trend of rainfall and streamflow necessary for the design of sustainable water management strategies and to reduce the impact of droughts and floods in the ARB.

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