Climate Change 1995 is a scientific assessment that was generated by more than 1 000 contributors from over 50 nations. It was jointly co-ordinated through two international agencies; the World Meteorological Organization and the United Nations Environment Programme. The assessment was completed by the Intergovernmental Panel on Climate Change (IPCC) with a primary aim of reviewing the current state of knowledge concerning the impacts of climate change on physical and ecological systems, human health, and socioeconomic factors. The second aim was to review the available information on the technical and economic feasibility of the potential mitigation and adaptation strategies.

Climate Change 1995

This note tests for the presence of a stable long-run relationship between the price of gold and inflation in the United States from 1945 to 2006 and from 1973 to 2006. Since both the gold market and the inflationary regime have been subjected to structural change over time, a novel unit root testing procedure is employed which allows for the timing of significant breaks to be estimated, rather than assumed exogenous. After taking these breaks into account, a modified cointegration approach provides strong evidence of a cointegrating relationship between gold and inflation in the post-war period and since the early 1970s. The results lend support to the widely held view that direct and indirect gold investment can serve as an effective inflationary hedge.

Gold investment as an inflationary hedge: Cointegration evidence with allowance for endogenous structural breaks

The livelihood of over 80% of the people of Southern region of Ethiopia is dependent on agriculture. However, the region is known by its food insecurity problem due to increasing population growth and alarmingly increasing natural resource degradation as well as unpredictability of rainfall. Therefore, it needs to assess the seasonal rainfall variability in selected areas of the region. Instat software version 3.36 was used to analyze and estimate the onset and end of the growing season, and the Length of Growing Period (LGP). Trend analysis for 17 rainfall stations’ data was also made by Mann-Kendall, Spearman test and Ordinary Least Square (OLS) methods. The Pattern of variability (coherent rainfall variability areas) was also identified by using Principal Component Analysis. The result shows that, the  annual rainfall in the region varied from slightly over 780 mm in Billate station to more than 2110 mm in Gerese station with mean, SD and CV as 1200 mm, 197 mm and 25% respectively and that of kiremt varied from 157 mm in Konso to 844 mm in Welkite with mean, SD and CV as 506 mm, 202 mm and 39% respectively. Belg seasonal rain varied from 863 mm in Gerese to 246mm in Bue with mean, SD and CV of 409mm, 121mm and 30% respectively. CV of 15%-64% for kiremt, 17%-52% for March April May (MAM) and 12%-46% for annual were observed. For Kiremt season, CV greater than 30% was observed in 18 stations; between 20-30% in 10 stations and below 20% for 5 stations. The mean onset, end and LGP of the main growing season was found to be at Days of year (DOY) 92, DOY 286, and 193 days for Hosaina area; at DOY 117, DOY 290 and 169 days for Welkite area; and at DOY 84, DOY 146 and 62days for Gato area respectively. OLS apparently showed a non significant decreasing linear trend for rainfall amount in 10 stations out of 17 while significant decreasing trend at Sawla; p= 0.04(-9.15 mm/yr) and Chida; p= 0.05(-16.08 mm/yr). However, for the start of MAM, March was unreliable in Hosaina and Welkite while reliable in Gato area. In addition, two homogenous areas of coherent rainfall variability, in terms of both seasons were obtained. This classification could be used for regional water management and rainfall prediction. Therefore, time of planting crops and other soil and water conservation activities should be performed accounting these variability parameters. Key words: Variability, Seasonal rainfall, rainfall trend, DOY (days of the year), Onset, End date, LGP, Homogenous rainfall areas.

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Analysis of Seasonal Rainfall Variability for Agricultural Water Resource Management in Southern Region, Ethiopia

The study estimated the carbon sequestration potential of 25 year old Tall x Tall coconut ( Cocos nucifera L. variety typica) plantations under S2 (highly suitable for coconut) and S4 (moderately suitable for coconut) soils in wet (WL3, high moisture availability), intermediate (IL1a, moderate moisture availability) and dry (DL3, low moisture availability) agro-climatic conditions during May to September 2009. Variation in total carbon stock (plant and soil), total carbon input (measured as Gross Primary Production of coconut, GPP), total carbon output (measured as plant and soil respiration) and net carbon balance of ecosystems were assessed. Eight coconut palms and sample plots per site were used for estimations (two factor factorial with eight replicates). There is a significant agro-ecological region (AER) x land suitability class (LSC) effect on all the components of the carbon balance in a coconut plantation. The total ecosystem carbon stock ( Btot – eco ) reduces along a decreasing moisture gradient from WL3 to DL3 and decreasing soil fertility gradient from S2 to S4. The GPP and Rtot – eco do not show a reduction along a decreasing moisture gradient from WL3 to DL3 on S2, whilst it shows a reduction from WL3 to DL3 on S4. The net C balance reduces from WL3 to DL3 on S4, whilst it does not reduce from WL3 to DL3 on S2. C stock of the ecosystem varied between 32 and 72 Mg C ha-1 whilst the net carbon balance varied between 0.4 and 1.9 Mg C ha-1 month-1 under different growth conditions. Of the measured components, GPP and maintenance respiration of coconut palms and soil respiration had greater contributions to the overall C balance of the system. This is the first report on carbon sequestration potential in coconut plantations of Sri Lanka. Keywords : Agro-ecological region, carbon sequestration, Cocos nucifera , gross primary production, net carbon balance, palm respiration, soil respiration. DOI: http://dx.doi.org/10.4038/jnsfsr.v40i1.4171 J.Natn.Sci.Foundation Sri Lanka 2012 40 (1):77-93

/pdf/estimation-of-carbon-sequestration-potential-in-coconut-1rwjg8hocr.pdf

Estimation of carbon sequestration potential in coconut plantations under different agro-ecological regions and land suitability classes

A single control chart is very famous to control assignable causes that shift the process because of variations in parameters (e.g., location and dispersion). Simultaneous monitoring of processes is another popular approach used for the bilateral processes. In this study, we have proposed the mixed control charts for simultaneously monitoring of process location and dispersion parameters. We have used the idea of mixed exponential weighted moving average and cumulative sum charts and designed the charting structures for simultaneous monitoring. The proposals are compared with several existing counterparts. The comparisons reveal numerous advantages of the proposed charts over the other existing scheme. The practical application of the proposed charts is also highlighted using an illustrative example based on a real dataset. Copyright © 2016 John Wiley & Sons, Ltd.

On the Performance of Control Charts for Simultaneous Monitoring of Location and Dispersion Parameters

Long term experiments are commonly analysed at the end of the experiment using all the data collected over the entire duration of the experiment. Various methods are adopted to analyse such data but, in general, little consideration is given to the effect of climatic factors during this period. Consequently, information gathered from such an analysis is often incomplete. An alternative approach for data analysis is proposed where the successive years of the experiment are classified jnto two states, namely, "Good year" and "Bad year" depending on the weather conditions. As a result, four different possible situations namely, "good year followed by a bad year", "good year followed by a good year", "bad year followed by a good year" and "bad year followed by a bad year" are considered. The method is illustrated using a data set from a trial carried out at the Coconut Research Institute and has demonstrated the feasibility of obtaining precise information on the treatment effect.

https://cocos.sljol.info/articles/10.4038/cocos.v7i0.2058/galley/1697/download/

An Alternative Approach for Analysis of Data from a Long-Term Experiment

The modeling of the weekly rainfall percentile is imperative for better understanding of rainfall patterns in any region. This study focuses on selecting the most appropriate probability distributions for weekly rainfall and use those to make reliable rainfall percentile with the 95% confidence intervals. Daily rainfall data of 56 years (1960–2015) during the South West Monsoon in Colombo City were used for this analysis. The three parameter Weibull distribution has been found most probable distribution for most of weekly rainfall totals. Weibull, two parameter Exponential, Exponential and Lognormal distributions were well fitted distributions for remaining totals. Based on the 95% confidence intervals of percentiles, the weeks 18–23, and 38–39 during SWM showed not only high rainfall, but also high rainfall variation results which caused high possibility to form extreme rainfall events. Heavy rainfall with great variation during the period of 30th April to 10th June and 17–30th of September was further confirmed by the result of running total of weekly rainfall.

Statistical modeling of weekly rainfall: A case study in Colombo City in Sri Lanka

Seasonal Autoregressive Integrated Moving Average (ARIMA) process of (0,1,2) x (0,1,1) x 6 that best fits a set of crop‑wise coconut yield data, in Bandirippuwa, Lunuwila is identified with­out using variance stabilization transformation. In this process the present value of the series may be described as a linear function of the past observation of the series and past disturbances. The physical factors such as rainfall, temperature, day length etc. are not required for this method, however the past crop figures in the estate is needed. While such model is useful for short term fore­casting, it also gives the upper and lower limits of the forecasts at a given probability. These intervals would provide the quantified information on the degree of duration of the forecasts.

http://cri.nsf.ac.lk/bitstream/1/3363/2/CORD_5%282%29_67-76.pdf

Forecasting the crop yield of a coconut estate

An appraisal of coconut growers reactions and observations on CRI recommended cultural practices and other related issues

The Coconut Research Institute (CRI) conducts about 8-10 long-term (>3 years) field experiments to improve the coconut cultivation in Sri Lanka. The most robust design in field experiments of coconut is the randomized complete block design (RCBD) with plot size varied from four to six palms. The blocking is done based on visual observation of the soil properties of the experimental field. It has now become a serious problem in finding homogenous plots within the blocks for experiments in coconut. This study illustrates the impact of using single palm plot data from concluded experiments. Based on data of seven concluded field experiments of coconut with a plot size of six palms, it was found that the single palm plot can be recommended for coconut experiments without changing inference obtained with the plot size of six, irrespective of the years and locations. The percentage increase of precision varied from 0.4 to 15.8%. However, it is clear that single palm plots are feasible for coconut experimentation. The methodology illustrated in this study can be used for other tree crops too.

T. S. G. Peiris

Papers

An Alternative Approach for Analysis of Data from a Long-Term Experiment

Statistical modeling of weekly rainfall: A case study in Colombo City in Sri Lanka

Forecasting the crop yield of a coconut estate

An appraisal of coconut growers reactions and observations on CRI recommended cultural practices and other related issues

Feasibility of single palm plot in coconut experimentation