Olive classification according to external damage using image analysis.

The external appearance of an olive’s skin is the most decisive factor in determining its quality as a fruit. This work tries to establish a hierarchical model based on the features extracted from images of olives reflecting their external defects. Seven commercial categories of olives, established by product experts, were used: undamaged olives, mussel-scale or ‘serpeta’, hail-damaged or ‘granizo’, mill or ‘rehús’, wrinkled olive or ‘agostado’, purple olive and undefined-damage or ‘molestado’. The original images were processed using segmentation, colour parameters and morphological features of the defects and the whole fruits. The application of three consecutive discriminant analyses resulted in the correct classification of 97% and 75% of olives during calibration and validation, respectively. However the correct classification percentages vary greatly depending on the categories, ranging 80–100% during calibration and 38– 100% during validation

Automatic detection of skin defects in citrus fruits using a multivariate image analysis approach

One of the main problems in the post-harvest processing of citrus is the detection of visual defects in order to classify the fruit depending on their appearance. Species and cultivars of citrus present a high rate of unpredictability in texture and colour that makes it difficult to develop a general, unsupervised method able of perform this task. In this paper we study the use of a general approach that was originally developed for the detection of defects in random colour textures. It is based on a Multivariate Image Analysis strategy and uses Principal Component Analysis to extract a reference eigenspace from a matrix built by unfolding colour and spatial data from samples of defect-free peel. Test images are also unfolded and projected onto the reference eigenspace and the result is a score matrix which is used to compute defective maps based on the T2 statistic. In addition, a multiresolution scheme is introduced in the original method to speed up the process. Unlike the techniques commonly used for the detection of defects in fruits, this is an unsupervised method that only needs a few samples to be trained. It is also a simple approach that is suitable for real-time compliance. Experimental work was performed on 120 samples of oranges and mandarins from four different cultivars: Clemenules, Marisol, Fortune, and Valencia. The success ratio for the detection of individual defects was 91.5%, while the classification ratio of damaged/sound samples was 94.2%. These results show that the studied method can be suitable for the task of citrus inspection. © 2010 Elsevier B.V. All rights reserved.This work has been supported by the Spanish Ministry of Education (MEC) and by European FEDER funds, through the research projects DPI2007-66596-C02-01 (VISTAC) and DPI-2007-66596-C02-02.López García, F.; Andreu García, G.; Blasco Ivars, J.; Aleixos Borrás, MN.; Valiente González, JM. (2010). Automatic detection of skin defects in citrus fruits using a multivariate image analysis approach. Computers and Electronics in Agriculture. 71(2):189-197. doi:10.1016/j.compag.2010.02.001S18919771

Soil nitrous oxide flux following land‐use reversion from Miscanthus and SRC willow to perennial ryegrass

Decarbonization of the world's energy supply is essential to meet the targets of the 2016 Paris climate change agreement. One promising opportunity is the utilization of second generation, low input bioenergy crops such as Miscanthus and Short Rotation Coppice (SRC) willow. Research has previously been carried out on the greenhouse gas (GHG) balance of growing these feedstocks and land-use changes involved in converting conventional cropland to their production; however, there is almost no body of work understanding the costs associated with their end of life transitions back to conventional crops. It is likely that it is during crop interventions and land-use transitions that significant GHG fluxes might occur. Therefore, in this study, we investigated soil GHG fluxes over 82 weeks during transition from Miscanthus and SRC willow into perennial ryegrass in west Wales, UK. This study captured soil GHG fluxes at a weekly time step, alongside monthly changes in soil nitrogen and labile carbon and reports the results of regression modelling of suspected drivers. Methane fluxes were typically trivial; however, nitrous oxide (N2O) fluxes were notably affected, reverted plots produced significantly more N2O than retained controls and Miscanthus produced significantly higher fluxes overall than willow plots. N2O costs of reversion appeared to be contained within the first year of reversion when the Miscanthus plots produced an average pregrass flux of 0.13 mg N2O m−2 hr−1 while for willow, this was 0.03 mg N2O m−2 hr−1. Total N2O emission from reversion increased the carbon cost over the lifetime of the Miscanthus from 6.50 to 9.91 Mg CO2 eq. ha−1 while for the willow, this increase was from 9.61 to 10.42 Mg CO2 eq. ha−1. Despite these significant increases, the carbon cost of energy contained in these perennial crops remained far lower than the equivalent carbon cost of energy in coal. © 2018 The Authors. GCB Bioenergy Published by John Wiley & Sons Ltd

Greenhouse gas emissions from the energy crop oilseed rape (Brassica napus); the role of photosynthetically active radiation in diurnal N2O flux variation

Oilseed rape (OSR, Brassica napus L.) is an important feedstock for biodiesel, hence carbon dioxide (CO2), methane (CH4) and particularly fertiliser-derived nitrous oxide (N2O) emissions during cultivation must be quantified to assess putative greenhouse gas (GHG) savings, thus creating an urgent and increasing need for such data. Substrates of nitrification (ammonium (NH4)) and denitrification (nitrate (NO3)), the predominant N2O production pathways, were supplied separately and in combination to OSR in a UK field trial aiming to: i produce an accurate GHG budget of fertiliser application; ii characterise short to medium-term variation in GHG fluxes; iii establish the processes driving N2O emission. Three treatments were applied twice, one week apart: ammonium nitrate fertiliser (NH4NO3, 69 kg-1N ha-1) mimicking the farm management, ammonium chloride (NH4Cl, 34.4 kg-1N ha-1) and sodium nitrate (NaNO3, 34.6 kg-1N ha-1). We deployed SkyLine2D for the very first time, a novel automated chamber system to measure CO2, CH4 and N2O fluxes at unprecedented high temporal and spatial resolution from OSR. During three weeks following the fertiliser application, CH4 fluxes were negligible, but all treatments were a net sink for CO2 (ca. 100 g CO2 m-2). Cumulative N2O emissions (ca. 120 g CO2-eq m-2) from NH4NO3 were significantly greater (p< 0.04) than from NaNO3 (ca. 80 g CO2-eq m-2), but did not differ from NH4Cl (ca. 100 g CO2-eq m-2), and reduced the carbon-sink of photosynthesis so that OSR was a net GHG source in the fertiliser treatment. Diurnal variation in N2O emissions, peaking in the afternoon, was more strongly associated with photosynthetically active radiation (PAR) than temperature. This suggests that the supply of carbon (C) from photosynthate may have been the key driver of the observed diurnal pattern in N2O emission and thus should be considered in future process-based models of GHG emissions

The impact of an open waste disposal site on soil and groundwater pollution

A study has been carried out of a waste disposal site, located in the valley of a small creek, 3 km south of Canakkale city centre. The surface area of the site was around 10 000 square metres, and the total amount of waste deposited at the site since 1990 was approximately 100 000 tons. The major risks of the dump are its closeness to the university campus area to the south, the airport to the north, and residential areas encroaching towards the dump site. The nuisance caused by odour is high. The waste pile emplaced at the head of the tributary stream has caused channelling of the leachate to the creek, which is eventually washed towards the agricultural fields. The field investigation included surface geological, hydrogeochemical and geochemical studies. Water samples were collected at 11 points. Three observation wells were dug in front of the open waste disposal site. Soil samples from these observation wells were collected at 30, 70 and 150 cm depths, and some heavy metals were analysed. The concentrations of lead, copper and zinc in soil at the depth of 150 cm decreased with distance from the waste disposal site. Hydrogeochemical data analysis gave similar results

Geochemical fractions of trace metals in surface and core sections of aggregates in agricultural soils

Agrochemicals containing trace metals such as pesticides and fertilizer are intensively used in apple production systems in many countries. There is a risk of accumulation of trace metals, particularly in the sensitive root rhizosphere area. In this study, the trace metal concentrations of soils were determined in macroaggregates at the "mm scale" sampled from apple orchards. Soil samples were taken from five different locations at 0-20 cm soil depths in an apple orchard. Pseudo-total trace metal (Cd, Cr, Cu, Ni, Pb, and Zn) concentrations of soil samples separated from the surface and core sections of the soil aggregate were determined by digestion with Aqua regia. The modified BCR sequential extraction method was used to determine four operationally defined geochemical trace metal fractions in soil samples. The pseudo-total concentrations of Cd and Cu were significantly higher, and Zn was lower at the surface than in the core sections (paired-t test, p < 0.05) of soil aggregates. The concentrations of all trace metals in the acid-soluble fraction and reducible fractions were significantly higher at the surface of soil aggregates than those in the core section. The same was true for the sum of trace metal concentrations in the extracts of the three fractions considered potentially mobilizable, except for Cr. Our results demonstrated that Cd and Cu originated probably from agrochemicals accumulating significantly on aggregate surfaces, where they were in close contact with plant mots. The generally higher extractability of all trace metals on the surface of aggregates can be attributed to the preferential accumulation of newly-added trace metals in comparatively weakly bound chemical forms

Mısırda Protein ve Yağ Oranının FT-NIR (Fourier Dönüşümlü Yakın Kızıl Ötesi Yansıma) Spektroskopisi Yöntemi ile Tespitinde Örnek Tipi ve Kemometrik Metodun Etkisi

FT-NIR (Foruier Dönüşümlü- Kızıl Ötesi Yansıma) spektrokopisi gıda ve endüstriyel alanda örnek bileşenlerinin tespitinde aktif olarak kullanılan bir enstrümandır. Bu çalışmada farklı genetik özelliklere sahip hibrit ve saf hatlardan oluşan 260 adet mısır örneği materyal olarak kullanılmıştır. Bu örneklerde protein ve yağ oranı kantitatif tayinleri gerçekleştirilmiştir. Elde edilen bulgularla tane ve öğütülmüş halde FT-NIR cihazlarından alınan spektrum verileri kullanılarak kalibrasyon modelleri (n=227) oluşturulmuştur. Model geliştirme amacıyla Çoklu Doğrusal Regresyon (MLR) ve Kısmi En Küçük Kareler Regresyonu (PLSR) yöntemlerinden faydalanılmıştır. Oluşturulan modellerin güvenilirliği dış doğrulama işlemi (n=20) ile test edilmiştir. Araştırma sonucunda öğütülmüş örneklerle oluşturulan modellerde protein oranı için MLR (RMSEC=0.5482; SEE=0.5494; r=0.882; R2=0.7776) ve PLSR (RMSEC=0.5504; SEE=0.5516; r=0.880; R2=0.7758) yönteminin tahmin gücü bakımından benzerlik gösterdiği, yağ oranı için ise PLSR (RMSEC=0,4429; SEE=0,4439; r=0,719; R2=0,5179) yöntemine göre MLR modelinin tahmin gücünün daha yüksek olduğu anlaşılmıştır. Dış doğrulama sonrasında ise protein oranında modeller arasındaki durum değişmez iken, yağ oranında MLR modelinin daha doğru sonuçlar verdiği ortaya çıkmıştır. Tane örneklerinden alınan spektrumlara dayalı modellerin tahmin gücünün model doğrulama sonucunda kullanıma uygun olmadığı anlaşılmıştır. Sonuç olarak, kullanılan istatistik yöntemin ve ölçüm alınan örnek yapısının tahmin gücüne önemli bir etkisinin olduğu, bu çalışmada kullanılan ölçüm yönteminin öğütülmüş örnekler üzerinde daha başarılı sonuçlar verdiği anlaşılmıştır