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1.
PLoS One ; 16(12): e0251952, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34914721

RESUMO

Identifying crop loss at field parcel scale using satellite images is challenging: first, crop loss is caused by many factors during the growing season; second, reliable reference data about crop loss are lacking; third, there are many ways to define crop loss. This study investigates the feasibility of using satellite images to train machine learning (ML) models to classify agricultural field parcels into those with and without crop loss. The reference data for this study was provided by Finnish Food Authority (FFA) containing crop loss information of approximately 1.4 million field parcels in Finland covering about 3.5 million ha from 2000 to 2015. This reference data was combined with Normalised Difference Vegetation Index (NDVI) derived from Landsat 7 images, in which more than 80% of the possible data are missing. Despite the hard problem with extremely noisy data, among the four ML models we tested, random forest (with mean imputation and missing value indicators) achieved the average AUC (area under the ROC curve) of 0.688±0.059 over all 16 years with the range [0.602, 0.795] in identifying new crop-loss fields based on reference fields of the same year. To our knowledge, this is one of the first large scale benchmark study of using machine learning for crop loss classification at field parcel scale. The classification setting and trained models have numerous potential applications, for example, allowing government agencies or insurance companies to verify crop-loss claims by farmers and realise efficient agricultural monitoring.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Aprendizado de Máquina , Imagens de Satélites , Estações do Ano , Finlândia
2.
Front Plant Sci ; 10: 462, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31024608

RESUMO

Monocultural land use challenges sustainability of agriculture. Pre-crop value indicates the benefits of a previous crop for a subsequent crop in crop sequencing and facilitates diversification of agricultural systems. Traditional field experiments are resource intensive and evaluate pre-crop values only for a limited number of previous and subsequent crops. We developed a dynamic method based on Sentinel-2 derived Normalized Difference Vegetation Index (NDVI) values to estimate pre-crop values on a field parcel scale. The NDVI-values were compared to the region specific 90th percentile of each crop and year and thereby, an NDVI-gap was determined. The NDVI-gaps for each subsequent crop in the case of monocultural crop sequencing were compared to that for other previous crops in rotation and thereby, pre-crop values for a high number of previous and subsequent crop combinations were estimated. The pre-crop values ranged from +16% to -16%. Especially grain legumes and rapeseed were valuable as pre-crops, which is well in line with results from field experiments. Such data on pre-crop values can be updated and expanded every year. For the first time, a high number of previous and following crop combinations, originating from farmer's fields, is available to support diversification of currently monocultural crop sequencing patterns in agriculture.

3.
Environ Sci Pollut Res Int ; 24(23): 19313-19321, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28669092

RESUMO

Microplastics are widely spread in the environment, which along with still increasing production have aroused concern of their impacts on environmental health. The objective of this study is to quantify the number and mass of two most common textile fibers discharged from sequential machine washings to sewers. The number and mass of microfibers released from polyester and cotton textiles in the first wash varied in the range 2.1 × 105 to 1.3 × 107 and 0.12 to 0.33% w/w, respectively. Amounts of released microfibers showed a decreasing trend in sequential washes. The annual emission of polyester and cotton microfibers from household washing machines was estimated to be 154,000 (1.0 × 1014) and 411,000 kg (4.9 × 1014) in Finland (population 5.5 × 106). Due to the high emission values and sorption capacities, the polyester and cotton microfibers may play an important role in the transport and fate of chemical pollutants in the aquatic environment.


Assuntos
Fibra de Algodão , Monitoramento Ambiental/estatística & dados numéricos , Lavanderia/estatística & dados numéricos , Poliésteres , Têxteis/análise , Finlândia , Lavanderia/instrumentação , Têxteis/estatística & dados numéricos , Poluentes Químicos da Água/análise
4.
PLoS One ; 11(11): e0166403, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27870865

RESUMO

Diversification of agriculture was one of the strengthened aims of the greening payment of European Agricultural Policy (CAP) as diversification provides numerous ecosystems services compared to cereal-intensive crop rotations. This study focuses on current minor crops in Finland that have potential for expanded production and considers changes in their cropping areas, yield trends, breeding gains, roles in crop rotations and potential for improving resilience. Long-term datasets of Natural Resources Institute Finland and farmers' land use data from the Agency of Rural Affairs were used to analyze the above-mentioned trends and changes. The role of minor crops in rotations declined when early and late CAP periods were compared and that of cereal monocultures strengthened. Genetic yield potentials of minor crops have increased as also genetic improvements in quality traits, although some typical trade-offs with improved yields have also appeared. However, the gap between potential and attained yields has expanded, depending on the minor crop, as national yield trends have either stagnated or declined. When comparing genetic improvements of minor crops to those of the emerging major crop, spring wheat, breeding achievements in minor crops were lower. It was evident that the current agricultural policies in the prevailing market and the price environment have not encouraged cultivation of minor crops but further strengthened the role of cereal monocultures. We suggest optimization of agricultural land use, which is a core element of sustainable intensification, as a future means to couple long-term environmental sustainability with better success in economic profitability and social acceptability. This calls for development of effective policy instruments to support farmer's diversification actions.


Assuntos
Agricultura/métodos , Produtos Agrícolas/crescimento & desenvolvimento , Agricultura/legislação & jurisprudência , Conservação dos Recursos Naturais , Produtos Agrícolas/genética , Ecossistema , Finlândia , Locos de Características Quantitativas , Solo
5.
Ambio ; 44(6): 544-56, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25663562

RESUMO

The Finnish agri-environmental program (AEP) has been in operation for 20 years with >90 % farmer commitment. This study aimed to establish whether reduced nitrogen (N) and phosphorus (P) use has impacted spring cereal yields and quality based on comprehensive follow-up studies and long-term experiments. We found that the gap between genetic yield potential and attained yield has increased after the AEP was imposed. However, many contemporary changes in agricultural practices, driven by changes in prices and farm subsidies, also including the AEP, were likely reasons, together with reduced N, but not phosphorus use. Such overall changes in crop management coincided with stagnation or decline in yields and adverse changes in quality, but yield-removed N increased and residual N decreased. Further studies are needed to assess whether all the changes are environmentally, economically, and socially sustainable, and acceptable, in the long run. The concept of sustainable intensification is worth considering as a means to develop northern European agricultural systems to combine environmental benefits with productivity.


Assuntos
Agricultura/métodos , Conservação dos Recursos Naturais , Nitrogênio/análise , Fósforo/análise
6.
Environ Pollut ; 184: 391-6, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24100049

RESUMO

The artificial sweeteners sucralose (SCL), acesulfame (ACS), saccharin (SAC), and cyclamate (CYC) have been detected in environmental waters in Europe and North America. Higher environmental levels are expected in view of the increasing consumption of these food additives. In this study, an isotope-dilution mass spectrometry (IDMS) LC-MS/MS method was developed and validated for quantifying the four artificial sweeteners in boreal lakes (n = 3) and rivers (n = 12). The highest concentrations of ACS, SAC, CYC and SCL were 9,600, 490, 210 and 1000 ng/L, respectively. ACS and SAC were detected in all studied samples, and CYC and SCL in 98% and 56% of the samples. Seasonal trends of ACS and SAC were observed in some rivers. ACS and SCL concentrations in rivers correlated linearly with population equivalents of the wastewater treatment plants in the catchment areas, whereas SAC and CYC concentrations depend more on the source.


Assuntos
Água Doce/química , Edulcorantes/análise , Espectrometria de Massas em Tandem/métodos , Poluentes Químicos da Água/análise , Cromatografia Líquida , Monitoramento Ambiental , Finlândia , Edulcorantes/química , Poluição Química da Água/estatística & dados numéricos
7.
Environ Sci Pollut Res Int ; 20(11): 7979-87, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23512237

RESUMO

The objective of the Control of Hazardous Substances in the Baltic Sea (COHIBA) project is to support the implementation of the HELCOM Baltic Sea Action Plan regarding hazardous substances by developing joint actions to achieve the goal of "a Baltic Sea with life undisturbed by hazardous substances". One aim in the project was to identify the most important sources of 11 hazardous substances of special concern in the Baltic Sea. Among them are perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA). In this study, four perfluorinated alkyl acids (PFAAs) were studied: PFOA, PFOS, perfluorohexanoic acid (PFHxA) and perfluorodecanoic acid (PFDA). The occurrence of PFAAs in municipal and industrial wastewater treatment plant effluents (MWWTP1-3, IWWTP1), target industry effluent, storm water, landfill leachate and sludge was studied. Effluents were analysed six times and storm water, leachate and sludge were analysed twice, once in the warm season and once in the cold, during a 1-year sampling campaign. PFOS prevailed in two municipal effluents (MWWTP1 and 3) and industrial effluent (IWWTP1; 7.8-14, 8.0-640 and 320-1,300 ng/l, respectively). However, in one municipal effluent (MWWTP2) PFOA was, in a majority of sampling occasions, the predominant PFAA (9-15 ng/l) followed by PFOS (3.8-20 ng/l). The highest PFAA loads of the municipal effluents were found in the MWWTP3 receiving the biggest portion of industrial wastewater. In storm water the highest concentration was found for PFHxA (17 ng/l). The highest concentration of PFOS and PFOA were 9.9 and 5.1 ng/l, respectively. PFOS, PFOA and PFHxA were detected in every effluent, storm water and landfill leachate sample, whereas PFDA was detected in most of the samples (77%). In the target industry, PFOS concentrations varied between 1,400 and 18,000 µg/l. In addition, on one sampling occasion PFOA and PFHxA were found (0.027 and 0.009 µg/l, respectively). For effluents, PFAA mass flows into the Baltic Sea were calculated. For municipal wastewater treatment plants average mass flows per day varied for PFOS between 1,073 and 38,880 mg/day, for PFOA 960 and 2,700 mg/day, for PFHxA 408 and 1,269 mg/day and for PFDA 84 and 270 mg/day. In IWWTP mass flows for PFOS, PFOA, PFHxA and PFDA were 495 mg/d, 28 mg/d, 23 mg/d and 0.6 mg/g, respectively.


Assuntos
Monitoramento Ambiental , Fluorocarbonos/análise , Esgotos/química , Poluentes Químicos da Água/análise , Ácidos Alcanossulfônicos/análise , Drenagem Sanitária , Finlândia , Instalações de Eliminação de Resíduos , Eliminação de Resíduos Líquidos , Poluição Química da Água/estatística & dados numéricos
8.
Anal Bioanal Chem ; 403(7): 1931-8, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22526668

RESUMO

The increasing use and production of nanomaterials have led to growing concern over the release of new pollutants to the environment. Fullerenes have been a subject of intense research, both because of their unique chemistry and because of technological applications. The development of analytical methods to quantify the fullerenes in complex sample matrices is a crucial step in the study of their occurrence and exposure, and thus in risk assessment. This paper reports the development and optimisation of a method combining liquid chromatography with ion-trap mass spectrometry (LC-ITMS) for analysis of the fullerene C(60). Under the optimised chromatogram conditions, a C(18) analytical column had good selectivity for fullerenes C(60) and C(70), with retention times of 3.0 and 4.1 min, respectively. Mass spectrometric detection was tested and optimised using three common ionisation techniques-atmospheric-pressure chemical ionisation (APCI), atmospheric-pressure photoionisation (APPI), and electrospray ionisation (ESI). The molecular ion was most abundant for C (60) (-) (m/z=720) in APCI and APPI, whereas adduct ions were formed with the molecular ion in ESI. Finally, the performance of the three ionisation techniques examined was compared by use of five validation criteria. The instrument detection limit (8 ng mL(-1)), quantification limit (27 ng mL(-1)), detection sensitivity (90.2 ng mL(-1)), linear range (8-1,000 ng mL(-1)), and repeatability (15 %) of APPI make it the most promising ionisation technique for fullerene C(60) analysis.

9.
J Agric Food Chem ; 57(13): 5837-42, 2009 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-19496586

RESUMO

To characterize the range of variation in lignan content and composition caused by genotype and environment, seven dietary lignans, i.e., 7-hydroxymatairesinol, secoisolariciresinol, matairesinol, lariciresinol, pinoresinol, medioresinol, and syringaresinol, were analyzed by high-performance liquid chromatography-tandem mass spectrometry in whole-grain extracts of cereal samples collected at eight locations in Finland. In all, 28 winter rye, 73 spring wheat, and 55 spring oat samples were analyzed, representing 6, 9, and 5 cultivars, respectively. The total lignan content showed huge variations within the same cereal species: the range was 2500-6700 microg/100 g in the rye samples, 340-2270 microg/100 g in the wheat samples, and 820-2550 microg/100 g in the oat samples. The variations seemed to depend largely upon genetic differences. In rye, also environmental conditions affected the lignan content through grain size; smaller grains had significantly lower total lignan, syringaresinol, and lariciresinol content than larger grains. This study shows that varying cereal lignan concentrations reported in different studies may be, besides differences in analytical methods, largely dependent upon natural variations.


Assuntos
Avena/química , Lignanas/análise , Estações do Ano , Secale/química , Triticum/química , Avena/genética , Meio Ambiente , Genótipo , Secale/genética , Sementes/anatomia & histologia , Sementes/química , Triticum/genética
10.
Environ Geochem Health ; 30(2): 101-7, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18259880

RESUMO

Evidence for on site biodegradation may be difficult to provide at heterogeneous sites without additional experiments in controlled laboratory conditions. In this study, microbial activities measured as CO2 and CH4 production were compared in situ, in intact soil cores and in bottle microcosms containing sieved soils. In addition, biodegradation rates were determined by measuring the decrease in petroleum hydrocarbon concentrations at 7 degrees C in aerobic and anaerobic conditions. Elevated concentrations of CO2 and CH4 in the soil gas phase indicated that both the aerobic and anaerobic microbial activity potentials were high at the contaminated site. Aerobic and anaerobic microbial degradation rates in laboratory experiments of petroleum hydrocarbons were highest in soils from the most contaminated point and degradation in the aerobic and anaerobic microcosms was linear throughout the incubation, indicating mass-transfer-dependent degradation. Different results for microbial activity measurements were obtained in laboratory studies depending on pretreatment and size of the sample, even when the environmental conditions were mimicked. These differences may be related to differences in the gas exchange rates as well as in changes in the bioavailability of the contaminant in different analyses. When predicting by modeling the behavior of an aged contaminant it is relevant to adapt the models in use to correspond to conditions relevant at the contaminated sites. The variables used in the models should be based on data from the site and on experiments performed using the original aged contaminant without any additions.


Assuntos
Hidrocarbonetos/metabolismo , Petróleo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Aerobiose , Anaerobiose , Biodegradação Ambiental , Dióxido de Carbono/metabolismo , Finlândia , Metano/metabolismo , Oxigênio/metabolismo , Eliminação de Resíduos
11.
Planta ; 226(3): 639-46, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17497165

RESUMO

Enterolignans, also called "mammalian" lignans because they are formed in the intestine of mammals after ingestion of plant lignans, were identified for the first time in extracts of four tree species, i.e., in knot heartwood of the hardwood species Fagus sylvatica and in knot or stem heartwood of the softwood species Araucaria angustifolia, Picea smithiana, and Abies cilicia. They were also identified for the first time in grain extracts of cultivated plants, i.e., in 15 cereal species, in 3 nut species, and in sesame and linseeds. Furthermore, some plant lignans and enterolignans were identified in extracts of water from different sources, i.e., in sewage treatment plant influent and effluent and in humic water, and for the first time also in tap and seawater. They were present also in water processed through a water purification system (ultrapure water). As enterolignans seem to be abundant in the aquatic environment, the occurrence of enterolignans in plant sources is most likely due to uptake by the roots from the surrounding water. This uptake was also shown experimentally by treating wheat (Triticum aestivum ssp. vulgare) seeds with purified lignan-free water spiked with enterolactone (EL) during germination and growth. Both the remaining seeds and seedlings contained high EL levels, especially the roots. They also contained metabolites of EL, i.e., 7-hydroxy-EL and 7-oxo-EL.


Assuntos
Lignanas/análise , Mamíferos , Plantas/química , Água/química , Animais , Hidrólise , Lignanas/química , Extratos Vegetais/química
12.
J Agric Food Chem ; 53(18): 7279-87, 2005 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-16131143

RESUMO

Twenty-seven barley (Hordeum vulgare L.) samples collected from growing sites in Scandinavia in 2001 and 2002 were examined to study the effect of endosperm structure on malting behavior. Samples were micromalted, and several malt characteristics were measured. Samples were classified as having a mealier or steelier endosperm on the basis of light transflectance (LTm). Because endosperm structure is greatly dependent on protein content, three barley sample pairs with similar protein contents were chosen for further analysis. During malting, the steelier barley samples produced less root mass, but showed higher respiration losses and higher activities of starch-hydrolyzing enzymes. Malts made from steelier barley had a less friable structure, with more urea-soluble D hordein and more free amino nitrogen and soluble protein. The reason for these differences may lie in the structure or localization of the hordeins as well as the possible effects of endosperm packing on water uptake and movement of enzymes.


Assuntos
Hordeum/anatomia & histologia , Sementes/anatomia & histologia , Parede Celular/ultraestrutura , Fenômenos Químicos , Físico-Química , Glutens , Hordeum/química , Nitrogênio/análise , Proteínas de Plantas/análise , Proteínas de Plantas/química , Sementes/química , Sementes/enzimologia , Solubilidade , Amido/análise
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