The most time-consuming phase is the inventory analysis. This phase consist of three stages: data collection for each unit process of the system, calculation and allocation. The quantitative and qualitative data of input and output of the system can be measured, calculated or estimated and allocated in different classifications such as: products, co-products and waste; air, water or land pollution; or other ambiental aspects. The calculation of emissions is realized for each process using different methods. 2.1.3 Environmental impact assessment The environmental impact assessment aims study the significance of potential environmental impacts, associating the data obtained in the inventory with categories of specific impact. This phase …show more content…
The methodology used in each study was also compared and analysed to find out if it was compatible between the studies. All the data were put in a table to facilitate comparison and the main results were pointed out. The studies used different functional unit, system boundary and allocation method. It is also recommended to consider that different LCA studies adopt different sampling methods. Moreover, the farmers’ management can have greater influence than the type of production system. Therefore, comparisons should be made with full awareness of the uncertainties. Table 1: Comparison between one Dutch (Boer et al., 2008), one German (Hass el at., 2001) and two Swedish (Cederberg and Mattson, 2000; Cederberg and Flysjo, 2004) LCA studies. 3.1 Environmental impact categories 3.1.1 Acidification Emissions of inorganic substances to the soil and water can occur in nature. One example is the emission of nitrates, sulfates and phosphates that causes acidification in the soil and water. The acidification limits the plant growth and yields as a result of the reduction of essential nutrients availability at soils with low pH. In milk production the main elements that contribute to the acidification process are ammonia (NH3), nitrate (NOX) and sulfate (SO2). Those elements have different potential of H+ ions release (Dias, 2011). In the life cycle assessment those elements are standardized to create a comparability
The topic in this systematic review is clearly defined in the abstract & the introduction. Yes, the search for studies and other evidence was comprehensive and unbiased as it was able to be. Strict criteria were followed as described in Figure 1.
A total of 4219 studies were identified. After removal of duplicates and after exclusion criteria were applied, there were 13 studies to be included. All 13 were case series with controls.
| Based on explicit knowledge and this can be easy and fast to capture and analyse.Results can be generalised to larger populationsCan be repeated – therefore good test re-test reliability and validityStatistical analyses and interpretation are
The first section in the methods section describes the protocol to be followed. In order to find appropriate studies for the meta-analysis, Taylor and Swerdfeger, examined articles from Medline, Pubmed, Embase, and Google Scholar using the guidelines outlined by the Preferred Reporting Items for Systematic Review and Analysis (PRISMA) and independently assessed the risk of bias using the Newcastle-Ottawa Scale (NOS). Eslick then reviewed the articles. Following this, Taylor manually extracted the study design, the country of completion, sample sizes, interventions, outcome measures, and measures of effect from the articles. All literature had to be published and there was no language restriction on the studies,
Data used in this study is from a previously prepared collection for a different study and hence does not require any instruments. Use of Microsoft Excel and graphpad, an online software, helped in calculating the results and analyzing the data.
It does not appear within the context of the study that the literature review has bias or undue influence on the findings but rather to support their validity as the method of the study and findings of this study are presented from a different perspective. However to maintain a balanced perspective we should consider the reasons that to date only one previous study has been a
However, the pitfalls of the study are also included in this section as well as the factors that limited the study. This section should however, compare the results with those from other similar studies. Yet for this paper, that part was lacking. Besides, the paper discussed the potential limitations to the research as well as the strengths of the study (Viktrup, 2002). The study’s implication is also inclusive and is clearly structured and helpful. Finally, the paper had a conclusion that contained a summary and the recommendations.
This study was limited due to the small sample size. Although the conclusions are valid, more research with a
The study tools were applied on the study sample after ensuring their validity and reliability, and these tools are :
N/A – data was drawn from number of sources. A systematic review was performed by the authors.
Grove et.al’s critical appraisal of a published study guideline will be utilized to assess the quality of the research studies. First, this writer will look at key components of each study, which typically includes: publication title, abstract, introduction, literature review, research methods used to address the research question(s) or hypothesis, statistical analysis used, results, and the researcher’s interpretation and conclusion or recommended use of results to inform future research or practice. During careful reading of the each study, this writer will try to:
To be able to duplicate the study addressed in the article here are the parameters that need to be followed. The study type is a randomized controlled design using convenient sampling. The study was conducted over
The research methodology used in this study is a systematic review, a “method of making sense of large bodies of information, and a means of contributing to the answers to questions about what works and what does not” (Petticrew & Roberts, 2006, p. 2). According to Tranfield, Denyer and Smart (2003), “systematic reviews differ from traditional narrative reviews by adopting a replicable, scientific and transparent process that aims to minimize bias through exhaustive literature searches of published and unpublished studies and by providing an audit trail of the reviewers decisions, procedures and conclusions ” (p. 209). In the systematic review, all relevant studies on a specified topic area were synthesized (Petticrew & Roberts, 2006). This method asset with making recommendations based on the evidence.
An alpha level of p<.05 was used for all statistical test. The participants were described by descriptive statistics. The t-test, chi-square, and
Have to set objective to improve the environmental performance of operations and tackle biggest impact.