Seedbank persistence and emergence pattern of Argemone mexicana, Rapistrum rugosum and Sonchus oleraceus in the eastern grain region of Australia

AbstractA thorough understanding of the emergence pattern and persistence of weed seeds is a prerequisite in framing appropriate weed management options for noxious weeds. In a study conducted at the University of Queensland, Australia, the emergence and seed persistence behavior of three major weeds Sonchus oleraceous, Rapistrum rugosum, and Argemone mexicana were explored with seeds collected from Gatton and St George, Queensland, Australia, with an average annual rainfall of 760 and 470 mm, respectively. Seed persistence was evaluated by placing seeds at the surface layer (0 cm) or buried at 2 and 10 cm depths enclosed in nylon mesh bags and examined their viability for 42 months. In another study, the emergence pattern of four populations, each from these two locations, was evaluated under a rainfed environment in trays. In the mesh-bag study, rapid depletion of seed viability of S. oleraceous from the surface layer (within 18 months) and lack of seed persistence beyond two years from 2 and 10 cm depths were observed. In trays, S. oleraceous germinated 3 months after seeding in response to summer rains and there was progressive germination throughout the winter season reaching cumulative germination ranging from 22 to 29% for all the populations. In the mesh-bag study, it took about 30 months for the viability of seeds of R. rugosum to deplete at the surface layer and a proportion of seeds (5 to 13%) remained viable at 2 and 10 cm depths even at 42 months. Although fresh seeds of R. rugosum exhibit dormancy imposed due to the hard seed coat, a proportion of seeds germinated during the summer months in response to summer rains. Rapid loss of seed viability was observed for A. mexicana from the surface layer; however, more than 30% of the seeds were persistent at 2 and 10 cm depths at 42 months. Notably, poor emergence was observed for A. mexicana in trays and that was mostly confined to the winter season.

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Modeling the irrigation requirements for an experimental site in Northern Alberta, Canada

10.7287/peerj.preprints.696 ◽

2014 ◽

Author(s):

Michel Rahbeh ◽

David Chanasyk ◽

Shane Patterson

Keyword(s):

Water Table ◽

Root Zone ◽

Winter Season ◽

Growing Season ◽

Annual Rainfall ◽

Quality Model ◽

Experimental Site ◽

Supplementary Irrigation ◽

Northern Alberta ◽

Irrigation Requirements

A combined methodology of the Root Zone Water Quality Model (RZWQM), the generation of stochastic rainfall realizations, and an historical meteorological record were used to determine the supplementary irrigation requirement for an experimental site located in northern Alberta. The site receives an annual rainfall of approximately 500 mm yr -1, and contains a fluctuating water table. The simulated results showed maximum irrigation requirements of 270 mm, however, half that amount can be required during an average or wet growing season of mean rainfall of 350 and 500 mm, respectively. The irrigation requirements were influenced by rainfall amount and distribution, downward flux and the subsequent fluctuation of the water table and the depth of water table at the beginning of the growing season, which was influenced by the winter season precipitation. The simulated results suggested that a water table less than 2 m deep from the ground surface can significantly reduce the irrigation requirements. Therefore, the winter precipitation and initial depth of the water table are suitable indicators of the likely requirement of irrigation during the growing season.

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Response of Nutrient Omission and Irrigation Scheduling on Growth and Productivity of Maize

International Journal of Applied Sciences and Biotechnology ◽

10.3126/ijasbt.v8i3.31612 ◽

2020 ◽

Vol 8 (3) ◽

pp. 343-354

Author(s):

N.R. Acharya ◽

S.K. Sah ◽

A.K. Gautam ◽

A.P. Regmi

Keyword(s):

Grain Yield ◽

Sandy Loam ◽

Winter Season ◽

Grain Filling ◽

Irrigation Scheduling ◽

Recommended Dose ◽

Annual Rainfall ◽

Irrigation Level ◽

Main Plot ◽

Hybrid Maize

An experiment was conducted for response of nutrient omission to irrigation scheduling in hybrid maize during winter season of 2015 at farmer’s field Khajura, Banke where intense summer and severe winter occurs. Soil is sandy loam and climatically humid sub-tropical with average annual rainfall of 1000-1500 mm. The experiment was replicated 3 times with split plot design having plot size of 3 x 3.6 m2. There were three irrigation level as main plot; (30 -35 DAS, tasseling stage), (30-35 DAS, tasseling, grain filling stage), (tasseling stage) and six level of fertilizer dose as sub-plot; farmer fertilization practice (27.6:27.6:18 N-P-K kg ha-1), recommended dose of fertilizer (160:60:40 N-P-K kgha-1), 50 percent above recommended dose (240: 90: 60 N-P-K kg ha-1), N0PK (60:40 P-K kg ha-1), NP0K (160:40 N-K kg ha-1), NPK0 (160:60 N-P kg ha-1). 3 level of irrigation increased the grain yield (4333 kg ha-1) by 33.7% than 2 level of irrigation (3240.6 kg ha-1) and 78.4% than single irrigation (2428.8 kg ha-1). Similarly, 182.4% grain yield could be increased with RDF (4994.9 kg ha-1) than N0PK (1768.6 kg ha-1). Grain nutrient uptake was recorded 80.4% N (56.3 kg ha-1), 79% P (18.8 kg ha-1), 88.8% K (15.1 kg ha-1) higher with three levels of irrigation than single irrigation N (31.2 kg ha-1), P (10.5 kg ha-1), K (8 kg ha-1) and 184% N (64.6 kg ha-1), 183.7% P (21 kg ha-1) and 188% K (17 kg ha-1) was recorded higher with RDF than (N0PK) N (22.7 kg ha-1), P (7.4 kg ha-1), K (5.9 kg ha-1). Int. J. Appl. Sci. Biotechnol. Vol 8(3): 343-354

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Advanced Rainfall Trend Analysis of 117 Years over West Coast Plain and Hill Agro-Climatic Region of India

Atmosphere ◽

10.3390/atmos11111225 ◽

2020 ◽

Vol 11 (11) ◽

pp. 1225

Author(s):

Atul Saini ◽

Netrananda Sahu ◽

Pankaj Kumar ◽

Sridhara Nayak ◽

Weili Duan ◽

...

Keyword(s):

Trend Analysis ◽

West Coast ◽

Winter Season ◽

Recurrence Interval ◽

Annual Rainfall ◽

Rainfall Trend ◽

Climatic Region ◽

Monotonic Trend ◽

Slope Test ◽

The Impact

In this paper, the rainfall trend of the West Coast Plain and Hill Agro-Climatic Region is analyzed for 117 years (1901–2017). This region is a globally recognized biodiversity hotspot and known for one of the highest rainfall receiving regions in India. Rainfall grid dataset is used for the analysis of rainfall trends on monthly, seasonal, and decadal time scales. Modified Mann–Kendall’s test, Linear Regression, Innovative Trend Analysis, Sen’s Slope test, Weibull’s Recurrence Interval, Pearson’s Coefficient of Skewness, Consecutive Disparity Index, Kurtosis, and some other important statistical techniques are employed for trend analysis. Results indicate that the rainfall trend is significant in January, July, August, September as well as the Winter season. Among all the significant trends, January and July showed a decreasing rainfall trend. July has the highest contribution (30%) among all the obtained monotonic trend to annual rainfall and coincidentally has the highest trend magnitude. August and September months with a combined contribution of 30% to annual rainfall, show an increasing monotonic trend with high magnitude whereas Winter season shows a monotonic decreasing rainfall trend with comparatively low magnitudes. Decadal analysis along with the study of recurrence interval of excess and deficit years helps to understand the decadal rhythm of trend and the magnitude of extreme monthly and seasonal events. Skewness reveals that rainfall dataset of all the periodic results is right-skewed and the recurrence interval also supports the skewness results. Sharply decreasing rainfall in July and rising rainfall in August and September is predictive of the impact on agriculture, biodiversity and indicates the rainfall regime shift in the region.

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Added-value of satellite soil moisture assimilation in hydrological modelling: an evaluation through a large experiment over Europe

10.5194/egusphere-egu2020-16239 ◽

2020 ◽

Author(s):

Domenico De Santis ◽

Christian Massari ◽

Stefania Camici ◽

Sara Modanesi ◽

Luca Brocca ◽

...

Keyword(s):

Surface Layer ◽

Soil Moisture ◽

Winter Season ◽

Assimilation Efficiency ◽

Remotely Sensed ◽

Open Loop ◽

Added Value ◽

Observation Error ◽

Loop Model ◽

Rainfall Runoff

The increasing availability of remotely sensed soil moisture (SM) observations has brought great interest in their use in data assimilation (DA) frameworks in order to improve streamflow simulations. However, the added-value of assimilating satellite SM into rainfall-runoff models is still difficult to be quantified, and much more research is needed to fully understand benefits and limitations.Here, an extensive evaluation of remotely sensed SM assimilation on hydrological model performances was carried out, involving 775 catchments across Europe. Satellite observations for over a decade from the three ESA CCI SM products (ACTIVE, PASSIVE and COMBINED) were assimilated in a lumped rainfall-runoff model which includes a thin surface layer in its soil schematization, by using the Ensemble Kalman Filter (EnKF). Observations were mapped into the space of modelled surface layer SM through a monthly CDF-matching prior to DA, while the observation error variance was calibrated in every catchment in order to maximize the assimilation efficiency.The implemented DA procedure, aimed at reducing only random errors in SM variables, generally resulted in limited runoff improvements, although with some variability within the study domain. Factors emerging as relevant for the assessment of assimilation impact were: i) the open-loop (OL) model performance; ii) the remotely sensed SM accuracy for hydrological purposes; iii) the sensitivity of the catchment response to soil moisture dynamics; and also iv) issues in DA implementation (e.g., violations in theoretical assumptions).The open-loop model results contributed significantly to explain differences in assimilation performances observed within the study area as well as at the seasonal scale; overall, the high OL efficiency is the main cause of the slight improvements here observed after DA. The integration of satellite SM information, showing greater skills in correspondence of poorer streamflow simulations, confirmed a potential in reducing the effects of rainfall inaccuracies.The variability in satellite SM accuracy for hydrological purposes was also found to be relevant in DA assessment. The ACTIVE product assimilation generally provided the best streamflow results within the study catchments, followed by COMBINED and PASSIVE ones, while factors affecting the SM retrieval such as vegetation density and topographic complexity were not found to have a decisive effect on DA results.Low assimilation performances were obtained when runoff was dominated by snow dynamics (e.g., in the northern areas of the study domain, or in winter season at medium latitudes), due to the SM conditions having a negligible effect on the hydrological response.Finally, in basins where SM was persistently near the saturation value, deteriorations in hydrological simulations were observed, mainly attributable to violation of error normality hypothesis in EnKF due to the bounded nature of soil moisture.In conclusion, the added-value of assimilating remotely sensed SM into rainfall-runoff models was confirmed to be linked to multiple factors: understanding their contribution and interactions deserves further research and is fundamental to take full advantage of the potential of satellite SM retrievals, in parallel with their progress in terms of accuracy and resolutions.

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Gamba grass (Andropogon gayanus Kunth.) seed persistence and germination temperature tolerance

The Rangeland Journal ◽

10.1071/rj17125 ◽

2018 ◽

Vol 40 (5) ◽

pp. 463 ◽

Cited By ~ 1

Author(s):

Faiz F. Bebawi ◽

Shane D. Campbell ◽

Robert J. Mayer

Keyword(s):

Seed Viability ◽

Temperature Tolerance ◽

Burial Depth ◽

Soil Seed Banks ◽

Seed Persistence ◽

Dry Tropics ◽

Andropogon Gayanus ◽

Wide Range ◽

Higher Temperature ◽

National Significance

Gamba grass (Andropogon gayanus Kunth.) is a highly invasive, naturalised Weed of National Significance in Australia due to its economic, environmental and social impacts. It outcompetes native pastures and fuels intense fires in northern Australian rangelands. To aid management of current infestations and to better understand its potential distribution, this study determined the germination response of gamba grass under a range of constant (13°C−48°C) and alternating (11/7°C–52/42°C) temperature regimes and quantified the potential longevity of soil seed banks. The effect of different soil types, levels of pasture cover and burial depths on seed longevity was investigated in the Dry Tropics of northern Queensland. Germination of gamba grass occurred under a wide range of both constant (17°C−39°C) and alternating day/night temperatures (16/12°C–47/39°C), although the level of germination declined at the lower and higher temperature ranges. At the cooler temperatures, seed viability was not affected, but seeds went into a state of dormancy. The highest level of seed viability was recorded at the lowest constant temperature regime (13°C) and at the two lowest alternating temperatures (11/7°C and 16/12°C). A gradual but variable decline in viability occurred thereafter with increasing temperatures. At the higher temperature range (e.g. constant temperatures of 39°C−43°C and alternating temperatures of 47/39°C) both dormancy and loss of seed viability were occurring, but once alternating and constant temperatures reached above 47/39°C and 43°C all seeds were rendered unviable after 9 and 6 weeks respectively. In the Dry Tropics of northern Queensland, viability of seeds was <1% after 12 months and nil after 24 months, irrespective of soil type or vegetation cover. However, burial depth had a significant effect, with surface located seeds exhibiting a faster rate of decline in germination and viability than seeds buried below ground (i.e. 2.5–10 cm). These findings have implications for the duration of control/eradication programs (i.e. seed persistence) and also suggest that gamba grass has the potential to greatly expand its current distribution into the relatively cooler southern latitude areas of Australia.

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Effect of Irrigation and Fertilization on Growth and Yield in Coriander: A Review

Agricultural Reviews ◽

10.18805/ag.r-1816 ◽

2020 ◽

Author(s):

Harshita Singh ◽

Suryapal Singh ◽

V. P.S. Panghal

Keyword(s):

Crop Production ◽

Research Work ◽

Winter Season ◽

Growth Yield ◽

Growth And Yield ◽

Annual Rainfall ◽

Optimum Dose ◽

Determining Factors ◽

Successful Production

Coriander is second most important seed spice crop grown for its seed as well as leaves. Among the major yield determining factors, NPK fertilization along with correct supply of water play an important role in the quality and yield aspects of coriander. Since coriander is grown mainly in arid and semi-arid areas, water is one of the main constraints in crop production as these growing areas are deficit in annual rainfall. Coriander grown particularly during winter season requires assured irrigation for successful production. Also, dumping of huge quantity of fertilizers in the soil becomes uneconomical besides polluting the environment. Therefore, application of optimum dose of fertilizers not only increases the yield but also improves the quality of the crop as well as soil. Extensive research work has been reported on irrigation and fertilizer requirement of coriander. Therefore, an attempt is been made to review the information available regarding the irrigation and fertilization studies and their impact on growth, yield and other attributing parameters of coriander.

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Evaluation of chickpea varieties under compartmental bunding in rainfed situation

Legume Research - An International Journal ◽

10.18805/lr.v0iof.9379 ◽

2016 ◽

Author(s):

S. L. Patil ◽

N. Loganandhan ◽

M. N. Ramesha

Keyword(s):

Grain Yield ◽

Dry Matter ◽

Winter Season ◽

Annual Rainfall ◽

Conservation Practices ◽

Net Returns ◽

Matter Production ◽

Production Technologies ◽

Extension Gap

Compartmental bunding (CB) and improved chickpea varieties were evaluated in ten farmers’ fields during rainy-winter (kharif-rabi) seasons of 2012-13 in Vertisols at Bellary, India. Adopting improved chickpea varieties of BGD103 and JG11 during winter season increased the grain yields from 12.5 to 15.9%, respectively over locally cultivated A1 variety. The CB that was laid out during July (rainy season) conserved rainwater in-situ and further increased the grain yield of chickpea up to 36.7% in BGD103 and 43.9% in JG11. The increase in grain yield from 24.2% (JG11) to 27.8% (BGD103) indicates that CB is effective for in-situ rainwater conservation and improving profile soil moisture in Vertisols. However technology gap during study period was higher compared to extension gap and it was attributed to drought situation with only 81.2% of mean annual rainfall. Technology index was higher in this study and varied from 48.3% (Cultivation of BGD103 variety with CB) to 60.6% (Cultivation of JG11 variety without CB) indicating that technology index can be reduced and chickpea yields can be increased and sustained with adoption of improved chickpea production technologies including in-situ rainwater conservation practices at farmers fields. Correlation studies also indicate that grain weight, stover weight and total dry matter production per plant ultimately determine the chickpea grain and stover yields in the Vertisols of Bellary region during winter season. Higher gross and net returns with greater B:C ratio was observed with layout of farmers fields with CB and cultivation of JG11 variety.

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Analysis of trend rainfall: Case of North-Eastern Algeria

Journal of Water and Land Development ◽

10.2478/jwld-2018-0011 ◽

2018 ◽

Vol 36 (1) ◽

pp. 105-115 ◽

Cited By ~ 3

Author(s):

Dounia Mrad ◽

Yassine Djebbar ◽

Yahia Hammar

Keyword(s):

Arid Regions ◽

Winter Season ◽

Magnitude Estimate ◽

Annual Rainfall ◽

Distance Weighting ◽

North Eastern ◽

Eastern Algeria ◽

Annual Scale ◽

Inverse Distance ◽

Semi Arid

AbstractThe climatic change is a reality largely recognized today in the scientific community. Nevertheless, its impact on precipitation, especially on annual, monthly and seasonally rainfall in arid and semi-arid regions is not yet certain. Indeed, very few studies have dealt with this matter in Algeria.In this context to examine spatial distribution of annual and seasonal rainfall an attempt has been made using the inverse distance weighting (IDW) method. Trends and magnitude estimate of change in rainfall series were detected by Mann–Kendall tests and Sen's test slope, has been applied to the data registered of 35 stations in the watershed Constantinois Seybouse Mellegue (CSM) North-Eastern Algeria over a period of 43 years (1969–2012).Results from spatial plot of annual rainfall showed that the rainfall increases with altitude, but is higher for the stations exposed to moist winds. It also increases from east to west and conversely decreases as one moves away from the coast to the south. From statistical method showed that there are increase trends at 95% confidence at annual scale in some rainfall stations with high altitude and coastal stations during winter season.

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Analysis of rainfall by using Mann-Kendall trend, Sen’s slope and variability at five districts of south Gujarat, India

MAUSAM ◽

10.54302/mausam.v68i2.604 ◽

2021 ◽

Vol 68 (2) ◽

pp. 205-222 ◽

Cited By ~ 1

Author(s):

NEERAJ KUMAR ◽

C. C. PANCHAL ◽

S. K. CHANDRAWANSHI ◽

J. D. THANKI

Keyword(s):

Standard Deviation ◽

Monsoon Rainfall ◽

Monsoon Season ◽

Rainfall Variability ◽

Winter Season ◽

Annual Rainfall ◽

Present Contribution ◽

Sen’S Slope ◽

Post Monsoon ◽

Data Points

On the basis of past 115 years (1901-2015) rainfall data of five districts of south Gujarat, the Mann-Kendall trend, Sen’s slope and regression slope showed that annual and monsoon rainfall at Valsad, Dang and Surat shows the increasing trend while, that of Navsari and Bharuch districts are declining. The monsoon season (summer monsoon) rainfall variability of Valsad, Dang, Surat, Navsari and Bharuch districts was recorded is 30.1%, 30.9%, 35.9%. 33.3% and 38.6%. The high coefficient of variation (CV) denoted that the variability of rainfall is not equally distributed and the amount of rainfall is lowest. The Bharuch district the annual and monsoon CV per cent denoted that the variability of rainfall in both seasons are very high. Valsad was recorded lowest CV with highest rainfall while the data are represent that variability of rainfall which can varies Bharuch to Dang in different districts of south Gujarat. The data shows that Dang district comes under high rainfall and Bharuch under low rainfall on south Gujarat. A low standard deviation indicates that the data points tend to be close to the mean of the set, while a high standard deviation indicates that the data points are spread out over a wider range of values. Similarly high SD is reported at Dang district because of high range of rainfall and lowest SD is found at Bharuch district because of low rainfall variability. The rainfall distribution different season viz., pre monsoon, monsoon post monsoon and winter season, the highest present contribution of rainfall is observed during monsoon season followed by post monsoon in all the five districts of south Gujarat. Rainfall contribution during remaining months was less than one per cent. While month wise analysis shows during monsoon season highest rainfall per cent contribution to annual rainfall is in July followed by August and June months at all the five districts of south Gujarat.

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Variability and Trend Analysis of Rainfall Data of Shillong and Agartala Stations of North East India

International Journal of Environment and Climate Change ◽

10.9734/ijecc/2020/v10i1130273 ◽

2020 ◽

pp. 134-142

Author(s):

Mirbana Lusick K. Sangma ◽

Hamtoiti Reang ◽

G. T. Patle ◽

P. P. Dabral

Keyword(s):

Time Series ◽

Trend Analysis ◽

Winter Season ◽

Summer Season ◽

Annual Rainfall ◽

Rainfall Time Series ◽

North East ◽

South West ◽

Total Annual Rainfall ◽

Sw Monsoon

This paper discusses the variability in rainfall and trend analysis of annual and seasonal rainfall time series of Shillong and Agartala stations located in the north-east region of India. Commonly used non-parametric statistical methods namely Mann-Kendall and Sen’s slope estimator was used to analyse the seasonal and annual rainfall time series. Statistical analysis showed less variation in annual and south-west monsoon rainfall for both Shillong and Agartala stations. In the total annual rainfall, the share of south-west (SW) monsoon, north-east (NE) monsoon, winter season and summer season rainfall was observed 64.60%, 13.22%, 1.40% and 20.80%, respectively for Shillong station of Meghalaya state. However, the contribution of SW monsoon, NE monsoon, winter season and summer season rainfall in the total annual rainfall was 59.59%, 9.55%, 1.14% and 29.72%, respectively for Agartala station of Tripura state. Non-significant increasing trends of rainfall was observed by 4.54 mm/year, 2.80 mm/year and 2.54 mm/year for annual, SW monsoon, and summer season, whereas, non-significant decreasing trends in rainfall for NE monsoon and winter season was observed with a magnitude of 1.83 mm/year and 1.63 mm/year for Shillong, Meghalaya during 1992 to 2017. Results also revealed that rainfall increased by 1.07 mm/year and 0.18 mm/year in SW monsoon and winter season whereas, rainfall decreased by 7.64 mm/year, 2.58 mm/year and 1.29 mm/year during annual, NE monsoon and summer season non-significantly during 1995 to 2019 in case of Agartala. The findings of present study will be useful for water management and crop planning in hill agriculture of Meghalaya and Tripura state of India.

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