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1.
Rev Environ Contam Toxicol ; 252: 1-50, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31451946

RESUMO

Microbe-assisted organopollutant removal, or in planta crop decontamination, is based on an interactive system between organopollutant-degrading endophytic bacteria (DEBOP) and crops in alleviating organic toxins in plants. This script focuses on the fast-growing body of literature that has recently bloomed in organopollutant control in agricultural plants. The various facets of DEBOP under study include their colonization, distribution, plant growth-promoting mechanisms, and modes of action in the detoxification process in plants. Also, an assessment of the biotechnological advances, advantages, and bottlenecks in accelerating the implementation of this decontamination strategy will be undertaken. The highlighted key research directions from this review will shape the future of agro-environmental sustainability and preservation of human health.


Assuntos
Bactérias , Produtos Agrícolas/microbiologia , Endófitos , Poluentes do Solo/metabolismo , Agricultura , Produtos Agrícolas/metabolismo , Inativação Metabólica , Desenvolvimento Vegetal
2.
Waste Manag ; 101: 74-82, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31604160

RESUMO

Biosolarization utilizes organic amendments to produce biopesticide compounds in soil that can work in tandem with other stresses to inactivate agricultural pests. The prospect of using by-products from industrial almond processing as amendments for biosolarization was assessed. Soil mesocosms were used to simulate biosolarization using various almond by-products, application rates, and incubation times. Several potentially biopesticidal organic acids were identified and quantified in the soil, and the toxicity of soil extracts was evaluated for the root lesion nematode (Pratylenchus vulnus). It was determined that both almond hulls and a mixture of hulls and shells harbored several acids, the concentration of which was enhanced 1-7 fold via fermentation by native soil microbes. Organic acid concentration in the soil showed a significant linear relationship with the quantity of waste biomass amended. Extracts from soils containing at least 2.5% incorporated biomass by dry weight showed a 84-100% mortality of nematodes, which corresponded to acid concentrations 0.75 mg/g (2.0 g/L) or greater. This study showed that almond processing by-products - hulls and a hull and shell mixture - were suitable amendments for control of P. vulnus and potentially other soil agricultural pests in the context of biosolarization.


Assuntos
Agentes de Controle Biológico , Prunus dulcis , Agricultura , Biomassa , Solo
3.
Waste Manag ; 101: 106-115, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31605925

RESUMO

The development and design of innovative biomass waste to energy conversion processes is a key issue to pursue the implementation of circular economy and to endorse a sustainable management of agricultural land. Assessing the environmental and economic sustainability of such processes is of paramount importance to prevent the trade-off of their impacts. The present study focused on a novel biomass waste to energy conversion process based on thermocatalytic reforming (TCR). Two different agricultural waste substrates (olive wood pruning and digestate) were selected as reference cases for conversion to energy and valuable material fractions. Mass and energy balances allowed the calculation of environmental and economic indexes considering alternative scenarios for the final use of the energy and of the products obtained from the TCR conversion (i.e. syngas, bio-oil and bio-char). A sensitivity analysis was carried out to assess the robustness of results. The overall performances of the TCR process resulted strongly related to the characteristics of the biomass waste and to the possible use of the product fractions obtained in the TCR process. The use of bio-char for soil amendment, allowed by the high quality of bio-char obtained from the TCR, was a key point to improve the expected environmental and economic sustainability of the conversion process.


Assuntos
Agricultura , Madeira , Biomassa
4.
J Environ Manage ; 253: 109705, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31654927

RESUMO

In this paper, we try to understand pesticide input decisions among Vietnamese rice producers by examining the production risk effects of pesticide use, applying both a lottery game and a more traditional production function approach. Production function estimates show that excessive pesticide use makes production riskier. This result is supported by the lottery approach, which signals that more risk averse farmers use less pesticide, implying that pesticide is a risk-increasing input. We also show, that higher uncertainty regarding drought relative to pest is likely driving the increasing risk effect of pesticides. Therefore, we claim that the relative importance of multiple uncertainties on pest and water is relevant to determine the risk property of pesticide.


Assuntos
Oryza , Praguicidas , Agricultura , Fazendeiros , Humanos , Vietnã
5.
J Environ Manage ; 253: 109717, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31655462

RESUMO

In the present study, the impact of different soil surface mulching, fertilization on phosphorus mineralization and bio-availability of spring maize at various growth stages and soil layers (0-20 and 20-40 cm soil layer) were evaluated. The results indicated that the contents of total P and Olsen-Phosphorus (Olsen-P) in the soils of 0-20 cm soil layer were significantly higher than those in the 20-40 cm soil layer at different stages. The addition of organic fertilizer significantly increased the soil total P and Olsen-P content in the 0-20 cm soil layer. The different surface mulching, no mulching (NM), gravel mulching (GM) and film mulching (FM) were significantly affected by the content of Olsen-P in both soil layers during the critical growth period of spring maize. The Ca10-P contents in both soil layers were the maximum in terms of the inorganic phosphorus content in soils with different surface mulching and different fertilization. Surface mulching significantly affected the transformation of inorganic phosphorus in different soil layers of dry-land farmland, and accelerated the increase of Ca2-P content (first phosphorus source) in 0-20 cm soil layer by GM and FM. In addition, phosphorus combined with inorganic nitrogen fertilizer increased Ca8-P (second Olsen-P source) to a certain extent, and reduced the relative content of Ca2-P (first phosphorus source). Compared with phosphate (P), nitrogen and phosphorus (NP) treatments, manure and nitrogen and phosphorus (MNP) treatments increased the contents of Ca2-P (first phosphorus source) and Ca8-P (second effective phosphorus source), while it reduced the insoluble phosphorus source (O-P) content.


Assuntos
Fertilizantes , Fósforo , Agricultura , China , Fazendas , Esterco , Nitrogênio , Solo
6.
J Environ Manage ; 253: 109687, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31666211

RESUMO

Stream losses are extensively observed due to human activities in the world, and the patterns of stream loss vary in different land use types. However, relationship between stream loss pattern and land use covers is poorly understood. We select the lower Taihu watershed (LTWS) within Yangtze River Delta (YRD), which is dominated by agricultural and urban covers and a typical case of most urbanized watersheds in China. In this study, we measured the stream loss of LTWS from 1960s to 2010s and investigated its relation to different land use covers and impervious area percentage (IAP) in order to figure out the main factor of stream loss in this area. The results show that urban area has tripled with fractional contribution from 10.3% to 33.18% in the form of conversion from agriculture to urban area during 1990-2015. 12.5% of all the streams are lost and 1st-order streams contribute most (91.8%) to the total stream loss. Urban cover contribute most (76%) to total streams loss compared to other land use types. We find that 1st-order streams have highest stream loss intensity, which is mainly caused by urban expansion, but preferred protections are given to highest-order streams. The linear model of correlation of pixel-level streams loss and IAP shows that the streams loss is statistically significant positive with IAP of cells (R2 = 0.91). Tradeoffs between city expansion and river network make small channels sacrifice for the urbanization. Urgent measures including legislation must be taken to protect small streams during urbanization nowadays and in future.


Assuntos
Agricultura , Rios , China , Cidades , Urbanização
7.
J Environ Manage ; 253: 109756, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31677424

RESUMO

Biogas is mainly discussed in the context of renewable energy, digestate is playing a minor role. However, in the upcoming EU Fertilizer Product Regulation digestate as eligible component material is in line with the circular economy action plan. This article discusses the quality of raw digestate based on analysis data from Austrian biogas plants regarding to the current Austrian as well as the European fertilizer regulatory framework. Therefore, a survey among Austrian biogas plant operators for results of digestate analysis and substrate input and energy output is used. The results show, that the legislative framework applies to a minimum of 1.5 million tonnes of digestate. Austrian digestate is of high quality with regards to the nutrient content, required limit values for heavy metals and is also safe with respect to their hygienic parameters. The following European fertilizer product function categories are available for international trade of digestate: "organic soil improver", "growing medium", and "organic, non-microbial plant biostimulant". Establishing legal criteria determining End-of-Waste and subsequently the product status for digestate is another important step in the European circular economy.


Assuntos
Comércio , Fertilizantes , Agricultura , Anaerobiose , Áustria , Biocombustíveis , União Europeia , Internacionalidade
8.
Food Chem ; 302: 125366, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31442705

RESUMO

Sambucus nigra is one of the richest sources of anthocyanins and other polyphenols being used industrially as a source of antioxidants, colorants, and bioactives. Although cultivars can influence elderberry composition, no study has addressed the effect of harvesting year on elderberries composition and bioactivity. The composition of the main Portuguese cultivars, "Sabugueiro", "Sabugueira" and "Bastardeira", were evaluated during three consecutive years. Harvesting year had a stronger influence on the chemical composition than cultivars, including total sugars, anthocyanins, and phenolic compounds, being related to the different climatic conditions, especially water status. "Bastardeira" was the best cultivar concerning total soluble solids, anthocyanins, polyphenols, and antioxidant activity, but containing a lower total free sugar content compared to "Sabugueiro". The results obtained in this study provide novel information from a nutritional perspective and for breeding programs aiming to select cultivars with enhanced levels of health-promoting compounds or for other industrial applications of elderberries.


Assuntos
Antocianinas/análise , Frutas/química , Fenóis/análise , Sambucus/química , Agricultura , Antioxidantes/análise , Ácido Oleanólico/análise , Extratos Vegetais/análise , Extratos Vegetais/química , Polifenóis/análise , Portugal , Sambucus nigra/química , Especificidade da Espécie , Triterpenos/análise
9.
Water Res ; 168: 115154, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31630020

RESUMO

Pyrrhotite is often considered as a gangue mineral, and discarded in mine wastes and tailings. Glyphosate and fertilizer, often excessively used in agriculture, flow into water bodies with agriculture runoff, and cause pollution of water bodies. In this study, the pyrrhotite was used as a substrate in a pilot constructed wetland (CW) to remove the glyphosate and nutrients from simulated agriculture runoff. In nearly one year, the pilot pyrrhotite constructed wetland (Pyrr-CW) removed 90.3 ±â€¯6.1% of glyphosate, 88.2 ±â€¯5.1 of total phosphorus (TP) and 60.40 ±â€¯5.60% of total nitrogen (TN) on average, much higher than the control CW. The abundances of sulfur-oxidizing bacteria, such as Sulfurifustis, Sulfuriferula and Thiobacillus, were much higher in the Pyrr-CW than those in the control CW. In the Pyrr-CW goethite was produced by pyrrhotite aerobic oxidation (PAO) and pyrrhotite autotrophic denitrification (PAD) continuously and spontaneously. Higher glyphosate and TP removals were resulted from adsorption on the goethite produced, and higher TN removal was attributed to the PAD. High glyphosate and nutrients removal could keep a long term until the pyrrhotite in the Pyrr-CW was used up. The phosphorus (P) sequestered in the Pyrr-CW existed mainly in organic P, (Fe + Al)P and (Ca + Mg)P, and their order was (Fe + Al)P > organic P > (Ca + Mg)P. No heavy metal ions released from the Pyrr-CW. With higher and lasting removal rate, and lower cost, the Pyrr-CW is a promising technology for simultaneous glyphosate and nutrients removal from agricultural runoff and wastewater.


Assuntos
Nutrientes , Áreas Alagadas , Agricultura , Glicina/análogos & derivados , Nitrogênio , Fósforo , Eliminação de Resíduos Líquidos , Águas Residuárias
10.
An Acad Bras Cienc ; 91(4): e20180695, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31721917

RESUMO

Conventional cotton production in western Bahia, Brazil, involves intensive use of agricultural inputs and mechanization, which may affect arbuscular mycorrhizal fungi (AMF). This work aimed at studying the impact of conventional and organic cotton production in the AMF of western Bahia. Soil samples were obtained from conventional white cotton and colored cotton organic production systems as well as from native Cerrado areas, close to the white cotton fields, and from the subcaducifolia vegetation, close to the organic colored cotton farms. The most frequent species in the conventional farming areas belonged to the genera Acaulospora (10 spp.); Glomus (8 spp.); Dentiscutata (3 spp.); Ambispora, Pacispora and Scutellospora (2 spp. each), as well as Claroideoglomus etunicatum, Diversispora sp., Entrophospora infrequens, Gigaspora sp., Orbispora pernambucana, Paradentiscutata maritima, and Paraglomus occultum. Eighteen species were found in the organic farming areas, with the predominance of Glomus (5 spp.) and Acaulospora (5 spp.), and with Claroideoglomus, Dentiscutata, Gigaspora, Corymbiglomus, Orbispora, Paraglomus, Scutellospora, and Simiglomus (1 spp. each). Paraglomus bolivianum was first reported in Cerrado. In the native vegetation, nine species were found, with the predominance of Glomus and Acaulospora. The highest number of AMF species was found in the organic farming areas, which deserves further investigation.


Assuntos
Gossypium/microbiologia , Micorrizas/classificação , Microbiologia do Solo , Agricultura , Brasil , Gossypium/crescimento & desenvolvimento
11.
Zootaxa ; 4664(1): zootaxa.4664.1.1, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31716686

RESUMO

We surveyed and identified species of lady beetles from the West Bank to document their geographic distribution and understand their ecological significance. This study documents the presence of 35 species of Coccinellidae in 19 genera belonging to 10 tribes and 6 subfamilies. Seven species (mostly very rare), out of the 35 documented, are recorded for the first time in the area studied. These are Nephus (Bipunctatus) bipunctatus, N. crucifer, Scymnus (Scymnus) interruptus, S. (Parapullus) abietis, S. (Neopullus) limbatus, S. nigropictus, and S. (Pullus) suturalis. Nephus peyerimhoffi, introduced to Palestine in 1986 and later considered extirpated, is recorded from three localities in this study. The distribution of many species generally correlates with local biogeographical zones. All species recorded during the study feed on agricultural pests such as aphids and scale insects. Previously published accounts have been very limited, and while more remains to be done, this study is currently the most comprehensive in the West Bank.


Assuntos
Afídeos , Besouros , Agricultura , Animais , Ecologia , Oriente Médio
12.
Zootaxa ; 4688(1): zootaxa.4688.1.7, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31719462

RESUMO

The genus Euschistus Dallas includes 67 species restricted to the New World, and several species are registered on cultivated plants in the Nearctic and Neotropical regions. In South America, most Euschistus species are completely overlooked due to the lack of information to allow accurate identification. Here, we redescribed Euschistus taurulus Berg, including for the first time, characterization of the internal and external genitalia of both sexes. We also report original information on bionomics, review and update information on geographical distribution and host plants records. Additionally, we provide DNA barcoding sequences for E. taurulus and three other morphologically similar key-agriculture pest species in South America: Euschistus heros (Fabricius), Dichelops melacanthus (Dallas), and Dichelops furcatus (Fabricius). We discuss means for correct identification of E. taurulus and its phylogenetic position within Euschistus and other similar stink bugs; the potential economic importance of the E. taurulus is also addressed.


Assuntos
Heterópteros , Agricultura , Animais , Feminino , Masculino , Filogenia , América do Sul
13.
Oecologia ; 191(4): 995-1002, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31691000

RESUMO

The responses of organisms to organic farming depend on the taxonomic group and landscape complexity. Following the intermediate landscape complexity hypothesis, organic farming can compensate for the lack of complexity in simple landscapes. Argentinian farmlands are simple with large fields and scarce linear habitat array, and conventional agriculture is almost the only agriculture practice. We hypothesize that there is an interaction effect of landscape complexity and farming practices on occupancy and species richness of small mammals in farmland of central Argentina. We selected circular landscapes under organic farming and low- and high-intensity conventional farming and quantified heterogeneity in each landscape considering different cover types (crops, resting plots, fallow land, border habitats, grasslands and man-made structures). We used multi-species occupancy models accounting for multiple seasons with a Bayesian approach to make the estimates. Landscapes under organic farms had the highest level of landscape heterogeneity. In simple Argentinian farmlands, organic farming benefited species richness and occupancy of all small mammal species. Some management strategies used in organic farming (wide and vegetated border habitats, diversity in types of production, winter cover crops, natural or semi-natural patches) should be taken into account to increase landscape complexity in conventional farming.


Assuntos
Agricultura , Biodiversidade , Animais , Argentina , Teorema de Bayes , Ecossistema , Fazendas , Mamíferos
14.
Nature ; 575(7781): 98-108, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31695208

RESUMO

Much of the Earth's biosphere has been appropriated for the production of harvestable biomass in the form of food, fuel and fibre. Here we show that the simplification and intensification of these systems and their growing connection to international markets has yielded a global production ecosystem that is homogenous, highly connected and characterized by weakened internal feedbacks. We argue that these features converge to yield high and predictable supplies of biomass in the short term, but create conditions for novel and pervasive risks to emerge and interact in the longer term. Steering the global production ecosystem towards a sustainable trajectory will require the redirection of finance, increased transparency and traceability in supply chains, and the participation of a multitude of players, including integrated 'keystone actors' such as multinational corporations.


Assuntos
Biomassa , Ecossistema , Fontes Geradoras de Energia , Retroalimentação , Abastecimento de Alimentos , Atividades Humanas , Desenvolvimento Sustentável , Agricultura/economia , Animais , Comércio/economia , Fontes Geradoras de Energia/economia , Abastecimento de Alimentos/economia , Agricultura Florestal , Água Subterrânea/análise , Atividades Humanas/economia , Humanos , Desenvolvimento Sustentável/economia
15.
Zootaxa ; 4619(3): zootaxa.4619.3.11, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31716297

RESUMO

We describe a specimen of Apostolepis phillipsi Harvey, 1999, from Vila Bela da Santíssima Trindade, Mato Grosso, establishing the first unambiguous record of the species in Brazil. The new locality is ca. 120 km from the type locality, in Bolivia. We present an updated species diagnosis, the first image of a living specimen, and the first description of A. phillipsi coloration in life. Even though the Brazilian range of A. phillipsi lies within a protected area (Parque Estadual Serra Ricardo Franco-PESRF), it is threatened by cattle raising, logging and agriculture. PESRF lacks formal delimitation and a management plan, and the Mato Grosso State Legislature is considering a decree to extinguish PESRF, which could cause the extirpation of the Brazilian range of several endemic species.


Assuntos
Serpentes , Agricultura , Animais , Bolívia , Brasil , Bovinos
16.
Environ Manage ; 64(6): 772-782, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31748948

RESUMO

During the last decade, China's agro-food production has increased rapidly and been accompanied by the challenge of increasing greenhouse gas (GHG) emissions and other environmental pollutants from fertilizers, pesticides, and intensive energy use. Understanding the energy use and environmental impacts of crop production will help identify environmentally damaging hotspots of agro-production, allowing environmental impacts to be assessed and crop management strategies optimized. Conventional farming has been widely employed in wolfberry (Lycium barbarum) cultivation in China, which is an important cash tree crop not only for the rural economy but also from an ecological standpoint. Energy use and global warming potential (GWP) were investigated in a wolfberry production system in the Yellow River irrigated Jingtai region of Gansu. In total, 52 household farms were randomly selected to conduct the investigation using questionnaires. Total energy input and output were 321,800.73 and 166,888.80 MJ ha-1, respectively, in the production system. The highest share of energy inputs was found to be electricity consumption for lifting irrigation water, accounting for 68.52%, followed by chemical fertilizer application (11.37%). Energy use efficiency was 0.52 when considering both fruit and pruned wood. Nonrenewable energy use (88.52%) was far larger than the renewable energy input. The share of GWP of different inputs were 64.52% electricity, 27.72% nitrogen (N) fertilizer, 5.07% phosphate, 2.32% diesel, and 0.37% potassium, respectively. The highest share was related to electricity consumption for irrigation, followed by N fertilizer use. Total GWP in the wolfberry planting system was 26,018.64 kg CO2 eq ha-1 and the share of CO2, N2O, and CH4 were 99.47%, 0.48%, and negligible respectively with CO2 being dominant. Pathways for reducing energy use and GHG emission mitigation include: conversion to low carbon farming to establish a sustainable and cleaner production system with options of raising water use efficiency by adopting a seasonal gradient water pricing system and advanced irrigation techniques; reducing synthetic fertilizer use; and policy support: smallholder farmland transfer (concentration) for scale production, credit (small- and low-interest credit) and tax breaks.


Assuntos
Aquecimento Global , Lycium , Agricultura , Carbono , China , Fertilizantes , Efeito Estufa , Metano , Óxido Nitroso
17.
J Environ Manage ; 251: 109621, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31569021

RESUMO

The application of organic fertilizer by farmers is an important method for promoting the transition of agricultural production from increasing the yield to improving the quality and safety of agricultural products and realizing the green development of agriculture. The behavior of farmers can have a direct impact on organic fertilizer application, and the active participation of farmers can effectively reduce moral hazards and improve governance efficiency. A consensus appears to have been reached regarding the importance of land property rights stability (LPRS) for farmers' organic fertilizer application (FOFA) in China; however, few studies have focused on the conditions under which LPRS exerts an effect or the extent of the effect. Moreover, the grain-growing purpose and farm size are rarely included as driving factors underlying the impact of LPRS on FOFA; thus, biased estimations are easily formed. This study analyzed the influence mechanism of LPRS on FOFA and its dependent conditions using the 2017 China Rural Household Panel Survey from Zhejiang University and conducted an empirical analysis via a logit model. The results showed that LPRS could enable farmers to apply organic fertilizer, although the degree of its impact will vary due to differences in the grain-growing purpose and farm size. Currently, selling products is not conducive to the application of organic fertilizer and will reduce the positive impact of LPRS on the application of organic fertilizer by farmers, whereas expanding the farm size will enhance the positive impact of LPRS. The government should constantly improve the methods and channels for realizing high-quality and high-priced agricultural products and fully acknowledge the role of market demand in guiding farmers' agricultural production, which will increase their enthusiasm for organic fertilizer application. The government should also improve the contract management system for land transfer to strengthen the ability of farmers to expand their farm size to fully demonstrate the role of large-scale farmers.


Assuntos
Fazendeiros , Fertilizantes , Agricultura , China , Fazendas , Humanos , Propriedade
18.
Ambio ; 48(11): 1290-1303, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31625049

RESUMO

We use data from a survey of 2439 farmers in 5 countries around the Baltic Sea (Denmark, Estonia, Finland, Poland and Sweden) to investigate their preferences for adopting agricultural practices aimed at reducing nutrient leaching and greenhouse gas emissions. The measures considered are set-aside, catch crops and reduced fertilization. Contracts vary with respect to the area enrolled, contract length, possibility of premature termination, availability of professional advice and compensation. We quantitatively describe farmers' preferences in terms of their willingness-to-accept compensation for specific attributes of these contracts, if implemented. The results vary substantially between farm types (farmers' characteristics) and between the 5 countries, and support differentiation of contract obligations and payments to improve the uptake of Agri-Environmental Schemes. The results can be readily used to improve the design of country-specific nutrient reduction policies, in accordance with the next Common Agricultural Policy.


Assuntos
Fazendeiros , Nutrientes , Agricultura , Países Bálticos , Clima , Dinamarca , Estônia , Finlândia , Humanos , Polônia , Suécia
19.
J Environ Manage ; 252: 109623, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31605907

RESUMO

Climate change scenarios are widely used for exploring future changes in environmental systems. However, many aspects of the uncertainties associated with the use of climate change scenarios in environmental systems modeling have not yet been studied sufficiently. We explore how the way that baseline scenarios are defined and general circulation model (GCM) outputs are used affects climate change impact assessments of agricultural systems. Our study builds on a previously validated agricultural systems model, the Root Zone Water Quality Model (RZWQM), coupled with the Decision Support System for Agrotechnology Transfer (DSSAT), which models a tiled-drained field in central Illinois of the United States and uses nine GCM outputs to investigate the effects. Our model simulations demonstrated the following three results. Firstly, the evaluation of climate change impacts presented a significant difference between the types of baseline used. The baseline scenario should be defined using the bias-corrected retrospective GCM outputs. Secondly, once GCM outputs are bias-corrected, the selective use of GCM outputs did not add significant value over using all available GCM outputs to provide more plausible future descriptions of agricultural systems' responses. Notably, however, selective use may have impacts comparable to carbon dioxide (CO2) emission scenarios in the field-scale agricultural climate change impact assessments. Thirdly, raw GCM outputs should be avoided for the predictions of field-scale agricultural systems' responses to climate change. Our findings can help provide a clearer picture of how GCM outputs should be used in agricultural systems modeling and might enable us to have more plausible descriptions of how future agricultural systems might unfold.


Assuntos
Nitrogênio , Água , Agricultura , Mudança Climática , Illinois , Modelos Teóricos , Estudos Retrospectivos
20.
An Acad Bras Cienc ; 91(3): e20180578, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31596389

RESUMO

The aim of this study was to determine how often rural farmers in a watershed use no-tillage systems combined with crop rotation, contour farming and agricultural terraces. The study area was Paraná Watershed III (PB3) in the western region of Paraná State, and data from the 2006 Agricultural Census of the Brazilian Institute of Geography and Statistics were used. A frequency distribution analysis of farms as a function of the no-tillage (NT) area was conducted in combination with a cluster analysis of soil and water conservation practices (adoption of crop rotation, contour farming and agricultural terrace practices). The results showed that the farms in PB3 adopt adequate soil and water conservation practices, with 73% adopting NT combined with at least 2 other conservation practices; however, agricultural terracing was found to be the most neglected practice in the region. In addition, based on the soil and water conservation practices in the watershed, 5 groups of farms were identified, the worst of which, those located in the municipalities that mainly neglect conservation practices, live in areas with highly erodible soils.


Assuntos
Agricultura/métodos , Conservação dos Recursos Naturais/métodos , Produtos Agrícolas , Solo/química , Brasil , Água/análise , Abastecimento de Água
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