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1.
J Environ Manage ; 301: 113818, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34597948

RESUMO

Best management practices that reduce potential phosphorus (P) loss and provide flexibility in P fertilizer management are needed to help producers protect water quality while maintaining crop yield. This study examined the impacts of P fertilizer management (no P, fall broadcast P, and spring injected P) and cover crop use on annual concentrations and loads of sediment, total P, and dissolved reactive P (DRP) in edge-of-field runoff from a no-till corn (Zea mays)-soybean (Glycine max) rotation in the Central Great Plains, USA, from September 2015 through September 2019. The spring injected P fertilizer treatment generally had 19% less total P and 33% less DRP loss compared to the fall broadcast treatment, confirming the importance of P fertilizer management as a practice for reducing P loss. The addition of a cover crop had an inconsistent effect on total P loss, with no effect in 2016 and 2017, increasing loss in 2018 by 56%, and decreasing it in 2019 by 40%. The inconsistent impact of cover crops on total P loss was related to cover crop effects on sediment loss. Although cover crop impacts on total P losses were inconsistent, the addition of a cover crop increased DRP loss in three of four years. Cover crop use consistently reduced sediment loss, with greater sediment reduction when P fertilizer was applied. Results from this study highlight the benefit of cover crops for reducing sediment loss and the continued need for proper fertilizer management to reduce P loss from agricultural fields.


Assuntos
Fertilizantes , Fósforo , Agricultura , Fertilizantes/análise , Fósforo/análise , Soja , Movimentos da Água , Qualidade da Água , Zea mays
2.
J Environ Manage ; 301: 113812, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34601350

RESUMO

Removing vegetation cover from hill-slope land increases risk for soil erosion and delivery of sediment to waterways. In New Zealand's productive landscapes, clear-fell harvesting of forestry blocks and winter forage grazing by agricultural livestock are two significant causes of vegetation removal. Bare ground exposed by these activities varies annually and seasonally in location and spatial extent. Modelling soil erosion therefore requires temporally and spatially explicit mapping of this bare ground. We have developed an automated mapping method using time-series satellite imagery, thereby enabling wide-area coverage and ease of updating. The temporal analysis identifies land use along with the period of vegetation removal. It produces results per land parcel (in vector format) for use in a Geographic Information System. We present a description of our method, national maps and statistics of bare ground extent in New Zealand's hill-country forestry and winter forage grazing land in 2018, and an assessment of accuracy. The attributes of the mapped land parcels are designed for input into a soil erosion estimation model such as the New Zealand Universal Soil Loss Equation.


Assuntos
Agricultura Florestal , Erosão do Solo , Agricultura , Conservação dos Recursos Naturais , Monitoramento Ambiental , Sistemas de Informação Geográfica , Nova Zelândia , Solo
3.
J Environ Manage ; 301: 113813, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34607133

RESUMO

There is a growing interest in including blue carbon ecosystems (i.e., mangroves, tidal marshes and seagrasses) in climate mitigation programs in national and sub-national policies, with restoration and conservation of these ecosystems identified as potential activities to increase carbon accumulation through time. However, there is still a gap on the spatial scales needed to produce carbon offsets comparable with terrestrial or agricultural ecosystems. Here, we used the Coastal Blue Carbon InVEST 3.7.0 model to estimate future net carbon sequestration in blue carbon ecosystems along Australia's Great Barrier Reef (hereafter GBR) catchments, considering different management scenarios (i.e., reintroduction of tidal exchange through the removal of barriers, sea level rise, restoring low lying land) at three different spatial scales: whole GBR coastline, regional (14,000-16,300 ha), and local (335-370 ha) scales. The focus of the restoration (i.e., tidal marshes and/or mangroves) was dependent on data availability for each scenario. Furthermore, we also estimated the monetary value of carbon sequestration under each management scenario and spatial scale assessed in the study. We found that large scale restoration of tidal marshes could potentially sequester an additional ∼800,000 tonnes of CO2e by 2045 (potentially generating AU$12 million based on the average Australia carbon price), with greater opportunities when sea level rise is accounted for in the modelling. Also, we found that regional and local projects would generate up to 23 tonnes CO2e ha-1 by the end of the crediting period. Our results can guide future decisions in the blue carbon market and financing schemes, however, the return on investment is dependent on the carbon price and funding scheme available for project implementation.


Assuntos
Carbono , Ecossistema , Agricultura , Sequestro de Carbono , Áreas Alagadas
4.
J Environ Manage ; 301: 113858, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34607139

RESUMO

The agricultural cooperative may significantly impact the adoption of environmentally friendly production technologies, which eventually help the farmers with better living standards and productivity. However, critical evaluation of how and to what extent the cooperative organization's participation leads the farmer's adoption of environmentally friendly technology (EFT) is relatively unclear. Thus, to critically explore the knowledge gap, the study evaluates the effects of cooperative participation towards adopting environmentally friendly production technologies based on the theory of planned behavior (TPB). The key variables used in the study have been extracted from an extensive literature investigation, while the empirical data has been collected from October to December 2020 from 292 kiwi-fruit farmers within the Shaanxi province of China. Simultaneously, the partial least square of structural equation modeling (PLS-SEM) tools has been utilized to craft the final assessment. The factor loadings of all three latent variables have been statistically significant and interrelated for quantifying the proposed model. The statistically proven framework portrayed that cooperative organizations' participation positively impacts and shapes behavioral factors and facilitates the adoption of environmentally friendly production technologies. The study found the social structure like China, the impacts of cooperation could be crucial. As cooperative participation is an ample predictor for facilitating environmentally friendly technologies, the government should broaden the technical supports, and agricultural extension should also provide extended training for a smooth transition of the cooperatives.


Assuntos
Fazendeiros , Frutas , Agricultura , China , Humanos , Tecnologia
5.
J Environ Manage ; 301: 113886, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34619594

RESUMO

The conversion of primary forests to cultivation brings a significant change in soil carbon (C) forms. In the foothills of the Eastern Himalayan Region of India (Manipur), such conversions are prevalent. However, little is known about the response of C forms, particularly in deep soil, to land use conversion in the region. We evaluated changes in soil C forms (total organic, inorganic, and pools) and microbiological properties (up to 1.0 m depth) mediated by C when the 45-year-old forest had been cultivated for 18-25 years. The cultivated land uses were tree-based agroforestry (LAF: legumes, NAF: non-legumes), horticultural fruits (WHF: woody, NHF: non-wood, mainly vegetables), and paddy agriculture system (AUS: upland, ALS: lowlands). Forest conversion significantly (p < 0.05) decreased the total carbon (TC) in the surface soil (0.0-0.15 m) from 4.88 % to 3.04-3.93 % in the tree-based land uses (LAF, NAF, and WHF). TC further declined to 2.05-2.81 % under seasonal crops (NHF, AUS, and ALS). Seasonal crop cultivation also caused a higher decline in microbial biomass carbon, soil enzymes, and carbon pools (active and passive) than the tree-based land use with the soil depth. The vertical distribution of C in the soil profile was inconsistent: organic C (including C pools) decreased, while inorganic C increased. The profile TC stock to a depth of 1.0 m in the forest was 358.8 Mg ha-1, of which 81 % were organic C, and 19 % were inorganic C. In comparison with forest soil, total soil C stocks (organic and inorganic) decreased more (-44.1 to -55.1 %) in seasonal crops than in tree-based (-15.4 to -36.3 %) land uses. The degradation index (DI) also confirmed that seasonal crop cultivation caused a larger decline in surface soil quality (DI: -423 % to -623 %) than tree-based land use (DI: -243 % to -317 %). The topsoil (up to 0.45 m) of seasonal crops was more degraded than that of the subsoil (>0.45 m-1.0 m). Forests converted to seasonal cultivation (upland rice and vegetables) caused higher degradation of soil C forms and overall soil health in the Himalayan foothills of northeastern India. We suggest the promotion of Agroforestry based on legumes (Parkia spp.) and woody fruits (mango/citrus/guava) in the uplands to minimize soil C degradation while ensuring nutritional security in the hill agro-ecosystems of the Indian Himalayas.


Assuntos
Carbono , Solo , Agricultura , Carbono/análise , Ecossistema , Florestas , Índia
6.
J Environ Manage ; 301: 113909, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34624580

RESUMO

To promote international collaboration on environmental pollution management and human health protection, we conducted a global-level study on the management of pesticides for surface freshwater quality. Prior to actions being taken in terms of water treatment or remediation, it is essential that clear and definite regulations be disseminated. In our study, 3094 surface freshwater quality standards for 184 different pesticides were recorded from 53 countries and categorized according to pesticide types and standard types, as well as diverse use of freshwater by humans, and compared water quality standards related to human health. Our results indicate large variations in pesticide regulations, standard types (i.e., long- or short-term water quality standards), and related numerical values. With regard to the protection of human health, the 10 most frequently regulated pesticides account for approximately 47% of the total number of standards across 184 considered pesticides. The average occurrence-weighted variations of standard values (i.e., numerical values provided in a standard in terms of residue limits of a given pesticide in water) for the 20 most regulated persistent organic pollutants (POPs) and other phase-out pesticides (i.e., pesticides not currently-approved for use in agriculture across various countries) are 4.1 and 2.6 orders of magnitude, respectively, with human-exposure related standard values for some pesticides varying with over 3 orders of magnitude (e.g., lindane). In addition, variations in water quality standard values occurred across standard types (e.g., maximum and average), water use types (e.g., unspecified waters and human consumption), and standard values (e.g., pesticide individuals and groups). We conclude that regulatory inconsistencies emphasize the need for international collaboration on domestic water treatment, environmental management as well as specific water quality standards for the wider range of current-use pesticides, thereby improving global harmonization in support of protecting human health.


Assuntos
Praguicidas , Poluentes Químicos da Água , Purificação da Água , Agricultura , Monitoramento Ambiental , Água Doce , Humanos , Praguicidas/análise , Poluentes Químicos da Água/análise
7.
J Environ Manage ; 301: 113880, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34638042

RESUMO

The dairy industry produces vast quantities of dairy processing sludge (DPS), which can be processed further to develop second generation products such as struvite, biochars and ashes (collectively known as STRUBIAS). These bio-based fertilizers have heterogeneous nutrient and metal contents, resulting in a range of possible application rates. To avoid nutrient losses to water or bioaccumulation of metals in soil or crops, it is important that rates applied to land are safe and adhere to the maximum legal application rates similar to inorganic fertilizers. This study collected and analysed nutrient and metal content of all major DPS (n = 84) and DPS-derived STRUBIAS products (n = 10), and created an application calculator in MS Excel™ to provide guidance on maximum legal application rates for ryegrass and spring wheat across plant available phosphorus (P) deficient soil to P-excess soil. The sample analysis showed that raw DPS and DPS-derived STRUBIAS have high P contents ranging from 10.1 to 122 g kg-1. Nitrogen (N) in DPS was high, whereas N concentrations decreased in thermo-chemical STRUBIAS products (chars and ash) due to the high temperatures used in their formation. The heavy metal content of DPS and DPS-derived STRUBIAS was significantly lower than the EU imposed limits. Using the calculator, application rates of DPS and DPS-derived STRUBIAS materials (dry weight) ranged from 0 to 4.0 tonnes ha-1 y-1 for ryegrass and 0-4.5 tonnes ha-1 y-1 for spring wheat. The estimated heavy metal ingestion to soil annually by the application of the DPS and DPS-derived STRUBIAS products was lower than the EU guideline on soil metal accumulation. The calculator is adaptable for any bio-based fertilizer, soil and crop type, and future work should continue to characterise and incorporate new DPS and DPS-derived STRUBIAS products into the database presented in this paper. In addition, safe application rates pertaining to other regulated pollutants or emerging contaminants that may be identified in these products should be included. The fertilizer replacement value of these products, taken from long-term field studies, should be factored into application rates.


Assuntos
Agricultura , Metais Pesados , Fertilizantes/análise , Metais Pesados/análise , Fósforo , Esgotos , Solo
8.
Food Chem ; 367: 130667, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34339981

RESUMO

The main purpose of the present study was to investigate the effect of different fertilizers on the physicochemical properties, multi-element and volatile composition of cucumbers. All samples were divided into five groups according to different combinations and amounts of chicken manure, NPK 17-17-17 fertilizer and microbial fertilizer. The co-application of chicken manure (120,000 kg/ha) and NPK 17-17-17 fertilizer (750 kg/ha) achieved the best texture properties, whereas the addition of the microbial fertilizer at 6000 kg/ha significantly improved the color quality of cucumbers. Similarly, the co-application of chicken manure, NPK 17-17-17 fertilizer and microbial fertilizer at 6000 kg/ha enhanced the number and abundance of volatile components detected in the cucumbers. Cucumbers from the control group contained the highest levels of most of the determined elements. Overall, a combination of chicken manure, NPK 17-17-17 fertilizer and 6000 kg/ha microbial fertilizer is recommended as a relatively efficient fertilizer utilization for cucumbers.


Assuntos
Cucumis sativus , Fertilizantes , Agricultura , Fertilizantes/análise , Esterco , Solo
9.
Sci Total Environ ; 803: 149912, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34482134

RESUMO

Agricultural runoff is the main source of water pollution in Central Asia. Excessive nitrogen (N) inputs from overuse of chemical fertilizers are threatening regional water resources. However, the scarcity of quantitative data and simplified empirical models limit the reliability of grey water footprint (GWF), particularly in undeveloped regions. In this study, we developed an Integrated Excess Nitrogen Load Model (IENLM) to calculate excess N load and evaluate its potential water environmental pressure in Central Asia. The model optimized the biological N fixation and atmospheric N deposition modules by involving more environmental variables and human activities. Results showed that N fertilizer application contributed over 60% to total N input and was mainly responsible for 42.9% increase of total GWF from 101.5 to 145.0 billion m3 during 1992 - 2018. Water pollution level (WPL) increased from 0.55 in 1992 to 2.41 in 2018 and the pollution assimilation capacity of water systems has been fully consumed just by N load from agriculture since 2005. GWF intensity and grey water pollution - efficiency types in all Central Asian countries have improved in recent years except for Turkmenistan. N fertilizer application and agricultural economy development were the main driving factors induced N pollution. Results were validated by riverine nitrate concentrations and the estimates from prior studies. In future, combining the N fertilizer reduction with other farm management practices were projected to effectively improve the WPL. The modeling framework is favorable for N pollution research in data-scarce regions and provides a scientific basis for decision-making for agriculture and water resource managements.


Assuntos
Nitrogênio , Água , Agricultura , Humanos , Nitrogênio/análise , Reprodutibilidade dos Testes , Poluição da Água
10.
Sci Total Environ ; 803: 149933, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34482141

RESUMO

To ensure global food security, agriculture must increase productivity while reducing environmental impacts associated with chemical nitrogen (N) fertilisation. This necessitates towards more sustainable practices such as recycling organic waste to substitute chemical fertiliser N inputs. However, hitherto how such strategy controls the succession of microbial communities and their relationship with crop yields and environmental impacts have not been comprehensively investigated. We conducted a field experiment with vegetable production in China examining partial substitution (25-50%) of chemical fertiliser with organic forms (pig manure or municipal sludge compost) considering key sustainability metrics: productivity, soil health, environmental impacts and microbial communities. We demonstrate that partial organic substitution improved crop yields, prevented soil acidification and improved soil fertility. Treatments also reduced detrimental environmental impacts with lower N2O emission, N leaching and runoff, likely due to reduced inorganic nitrogen surplus. Microbial communities, including key genes involved in the N cycle, were dynamic and time-dependent in response to partial organic substitution, and were also important in regulating crop yields and environmental impacts. Partial organic substitution increased bacterial diversity and the relative abundance of several specific microbial groups (e.g. Sphingomonadales, Myxococcales, Planctomycetes, and Rhizobiales) involved in N cycling. Additionally, partial organic substitution reduced the number of bacterial ammonia oxidizers and increased the number of denitrifiers, with the proportion of N2O-reducers being more pronounced, suggesting a mechanism for reducing N2O emissions. Comprehensive economic cost-benefit evaluation showed that partial organic substitution increased economic benefit per unit area by 37-46%, and reduced agricultural inputs and environmental impacts per unit product by 22-44%. Among them, 50% substitution of pig manure was the most profitable strategy. The study is crucial to policy-making as it highlights the potential advantages of shifting towards systems balancing chemical and organic fertilisers with economic benefits for farmers, reduced environmental damage and an efficient way for organic waste disposal.


Assuntos
Agricultura , Fertilizantes , Animais , Fertilizantes/análise , Esterco , Nitrogênio , Solo , Suínos
11.
Sci Total Environ ; 803: 149902, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34482144

RESUMO

Nitrogen (N) use efficiency can be increased by the addition of substances to urea. Magnesium sulfate (MgSO4) and boron were considered as plant nutrients, while zeolite was used as soil conditioner. The addition of these substances may affect soil NH3 and N2O emissions, by increasing N use efficiency. We conducted an 30 days incubation experiment with ryegrass using fertilizer treatments (12 g N m-2) as follows: urea (U); urea + MgSO4 (UM); urea + MgSO4 + borax (UMB); zeolite + urea + MgSO4 (Z-UM); and zeolite + urea + MgSO4 + borax (Z-UMB). We measured NH3 and N2O emissions and the aboveground N uptake of ryegrass. Cumulative NH3 emissions of UM, UMB, Z-UM and Z-UMB were 10%, 53%, 21% and 58% lower than U, respectively, while their N2O emissions were 32%, 133%, 43% and 72% higher than U, respectively. Aboveground N uptake of UM, UMB, Z-UM and Z-UMB were 9%, 6%, 12% and 13% higher than U, respectively. Overall, we suggest that the addition of MgSO4 and borax were effective in reducing NH3 emissions and potentially increase plant N uptake. However, the risk of higher denitrification and N2O emissions also needs to be considered. This study reveals the considerable effect of MgSO4 and borax in soil N cycles. Future research should evaluate how the application of urea + MgSO4 + borax effects gaseous emissions and crop yield of dicotyledons and in drier soil conditions.


Assuntos
Solo , Ureia , Agricultura , Boratos , Fertilizantes/análise , Sulfato de Magnésio , Nitrogênio/análise , Óxido Nitroso/análise , Poaceae
12.
Sci Total Environ ; 803: 149990, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34492488

RESUMO

Increased food demands and ceasing nutrient deposits have resulted in a great shortfall between the food supply and demand and would be worse in the years to come. Higher inputs of synthetic fertilizers on lands have resulted in environmental pollution, persistent changes in the soil ecology, and physicochemical conditions. This has greatly decreased the natural soil fertility thereby hindering agricultural productivity, human health, and hygiene. Bio-based resilient nutrient sources as wastewater-derived algae are promising as a complete nutrient for agriculture and have the potential to be used in soilless cultivations. Innovations in nano-fortification and nano-sizing of minerals and algae have the potential to facilitate nutrients bioavailability and efficacy for a multifold increase in productivity. In this context, various options on minerals nanofertilizer application in agricultural food production besides efficient biofertilizer have been investigated. Algal biofertilizer with the nanoscale application has huge prospects for further agriculture productivities and fosters suitable development.


Assuntos
Agricultura , Fertilizantes , Fertilizantes/análise , Humanos , Minerais , Plantas , Solo
13.
Sci Total Environ ; 803: 149810, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34492489

RESUMO

Two-way feedbacks exist between water-stressed vegetation and agricultural drought. Previous studies have focused mainly on the responses of vegetation to agricultural droughts but rarely on those of agricultural droughts to vegetation. Based on a new drought index (AgDI) that incorporates dynamic climatic and vegetation information, this study evaluated the impacts of climate and vegetation variabilities on agricultural droughts in 20 catchments in southwestern China, a region frequently hit by droughts. Results showed that the drought-stressed vegetation tended to alleviate agricultural droughts, and the drought-alleviating ability of vegetation was affected by vegetation types and the magnitudes of the changes in climate. Compared to other types of vegetation, the natural forest generally has a greater ability to affect agricultural drought. Overall, the relative contribution (mean of 29.9 ± 24.6%) of changes in vegetation to agricultural drought was at least comparable to those of the changes in potential evapotranspiration (mean of 14.4 ± 12.7%). Results also showed that even though vegetation has the ability to alleviate agricultural droughts, the changes in agricultural droughts were still dominated by climate changes, especially precipitation (mean relative contribution of 55.7 ± 24.2%).


Assuntos
Secas , Florestas , Agricultura , Mudança Climática , Água
14.
Sci Total Environ ; 803: 149906, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34492495

RESUMO

Land use and land cover (LULC) scenarios in rural catchment hydrology are crucial to describe the effects of future water dynamics. However, there is a lack of understanding of the effectiveness of including static land covers at the subbasin level to provide inter-annual stability in changing the different water balance components. We developed a step-by-step mapping protocol to extend and enrich the hydrological assessment of future LULC scenarios defined through participatory stakeholder involvement. This novelty included specific allocation of static and dynamic LULC change among the scenarios and then compared the change of water dynamics to the current situation. For this, we quantified the LULC impact on the components of the water balance from three contrasting participatory scenarios implemented with the SWAT model in a rural basin in central Spain. The Land-sharing scenario (LSH) had the highest percentage of permanent grassland and shrubs and no increase of irrigated land compared to baseline. The land-sparing scenario (LSP) intensified agricultural land use close to urban areas, and the land balance scenario (LBA) was intermediate. The LSH increased the aquifer recharge by +1.7% and streamflow by +1.5%, while evapotranspiration and soil water storage decreased by -0.2%. In contrast, the LBA decreased in the riverine flux of -0.5%, an aquifer recharge of -0.6%, a soil water storage of -3.5%, and an evapotranspiration rate of +0.3%. Thus, LSH revealed that the allocation of permanent land cover such as grassland could buffer water dynamics, suggesting that dedicated planning and allocation of permanently vegetated LULC will favour land and water conservation.


Assuntos
Água Subterrânea , Hidrologia , Agricultura , Conservação dos Recursos Naturais , Solo
15.
Sci Total Environ ; 803: 150019, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34500267

RESUMO

Reducing nitrogen (N) losses from cropping systems to aquatic ecosystems is a global priority. In Australia, N losses from sugarcane production in catchments adjacent to the Great Barrier Reef (GBR) are threatening the health of this World Heritage-listed coral reef ecosystem. N losses from sugarcane can be reduced by improving fertiliser management. However, little is known about the contribution of organic sources of N, such as mill mud. We used more than 10 years of data from two of the main Australian sugarcane regions, a high (Wet Tropics) and moderate (Mackay Whitsundays) rainfall area, to calibrate and validate a model to predict dissolved inorganic nitrogen (DIN) losses in runoff from both inorganic and organic fertilisers. DIN losses in runoff were well simulated (RMSE = 0.37 and 2.0 kg N ha-1 for the Wet Tropics and Mackay Whitsunday regions, respectively). Long-term simulations of rate and fertiliser deductions to account for N from organic sources showed that adopting best management practices for organic fertiliser (applying ≤50 wet t ha-1 mill mud) can significantly reduce DIN in runoff losses compared with applications of 150 wet t ha-1. Simulations of typical farmer practices in relation to fallow management (bare fallow vs. legume fallow) and organic fertiliser placement (buried in a fallow but surface applied to a green cane trash blanket in ratoons) showed that inorganic fertiliser rates need to be adjusted to account for N inputs from both mill mud and legume crops. Rates of application of organic N had a larger impact on DIN runoff losses than placement or timing of application. This work presents a DIN in runoff modelling algorithm that can be coupled with nitrogen models readily available in agricultural models to assess the impact of nutrient management on the quality of water leaving agricultural systems.


Assuntos
Nitrogênio , Saccharum , Agricultura , Algoritmos , Austrália , Ecossistema , Monitoramento Ambiental , Nitrogênio/análise , Nutrientes , Fósforo/análise
16.
Sci Total Environ ; 803: 150035, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34500275

RESUMO

The Loess Plateau is China's primary apple-growing area, and the orchard is a significant source of greenhouse gases (GHGs) emissions due to high nitrogen fertilizer input. Thus, a two-year field study was carried out to investigate the effects of apple wood derived biochar on GHGs emissions during apple orchard production, including soil organic carbon sequestration (SOCSR) and net global warming potential (NGWP) assessments. There are four treatments in this study: 20 t ha-1 biochar in a non-fertilized plot (B); no biochar in a fertilized plot (F); 20 t ha-1 biochar in a fertilized plot (FB); no biochar in a non-fertilized plot (CK). Results showed that the combined application of biochar and fertilizer stimulated CO2 emissions by 9.25% and 8.39% than either biochar or fertilizer alone. Meanwhile, biochar in fertilized plot increased annual N2O emissions by 32.6% as compared to fertilized plot without biochar amendment. Compared with CK, biochar had no significant effect on GHG emissions in unfertilized plot. The N2O emission factor of FB and F were 0.91% and 0.45% respectively in 2017-2018 and they were both 0.34% in 2018-2019. Moreover, compared with CK, the FB and B treatments increased the SOCSR by 316.52% and 354.78%, while, decreased the NGWP by 368.93% and 480.91%, respectively. Thus, biochar application may help reduce the impact of apple production on climate change by sequestering more soil organic carbon and decreasing the NGWP.


Assuntos
Malus , Solo , Agricultura , Carbono , Dióxido de Carbono/análise , Sequestro de Carbono , Carvão Vegetal , China , Aquecimento Global , Metano/análise , Óxido Nitroso/análise
17.
J Environ Manage ; 301: 113776, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34619587

RESUMO

Agricultural landscapes are the leading edge in the advancement of sustainability and climate change adaptation. The purpose of this study is to endogenize culture as shaped by natural-cultural feedback into individuals' decision-making processes on sustainability policy support. We present an agent-based model in which an adaptive cultural decision-rule quantifies the probability of an agent deciding to support a wildlife area policy for the Smoky Hill River Watershed (SHRW) in Kansas, USA. By using an ABM to examine the watershed as a coupled natural and human system, we learned that agents would adopt a new behavior, voting for the policy, if the cultural conditions were right, with high levels of beliefs and norms for freshwater and its biota. Our results indicate that individuals in the SHRW are not engaged in caring for fish, plants, and bird richness in their rivers and playas with few individuals supporting the policy in the naïve cultural setting (8.9 % of simulated population). However, enough agents would support the policy under a lower cultural threshold (40.7 % of simulated population). Our results show that sustainability policies need to account for the local culture to gain support, and if a policy is culturally meaningful, it does not need to be cheap. For an agricultural landscape, such as those commonly found in the Central Great Plains, this study presents new levers for policymakers on the conditions needed to help assemble popular support for sustainability policies.


Assuntos
Agricultura , Mudança Climática , Conservação dos Recursos Naturais , Animais , Água Doce , Humanos , Políticas , Rios
18.
Food Chem ; 370: 131315, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34788958

RESUMO

Currently, agricultural production generates large amounts of organic waste, both from the maintenance of farms and crops (agricultural wastes) and from the industrialization of the product (food industry waste). In the case of Actinidia cultivation, agricultural waste groups together leaves, flowers, stems and roots while food industry by-products are represented by discarded fruits, skin and seeds. All these matrices are now underexploited and so, they can be revalued as a natural source of ingredients to be applied in food, cosmetic or pharmaceutical industries. Kiwifruit composition (phenolic compounds, volatile compounds, vitamins, minerals, dietary fiber, etc.) is an outstanding basis, especially for its high content in vitamin C and phenolic compounds. These compounds possess antioxidant, anti-inflammatory or antimicrobial activities, among other beneficial properties for health, but stand out for their digestive enhancement and prebiotic role. Although the biological properties of kiwi fruit have been analyzed, few studies show the high content of compounds with biological functions present in these by-products. Therefore, agricultural and food industry wastes derived from processing kiwi are regarded as useful matrices for the development of innovative applications in the food (pectins, softeners, milk coagulants, and colorants), cosmetic (ecological pigments) and pharmaceutical industry (fortified, functional, nutraceutical, or prebiotic foods). This strategy will provide economic and environmental benefits, turning this industry into a sustainable and environmentally friendly production system, promoting a circular and sustainable economy.


Assuntos
Aditivos Alimentares , Frutas , Agricultura , Antioxidantes , Indústria Alimentícia , Sementes
19.
Chemosphere ; 286(Pt 1): 131665, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34315076

RESUMO

Legacy phosphorus (P) has accelerated the subsurface transport of colloidal P (CP) in intensively managed agricultural soils in the Midwestern U.S. Because of its high P sorption capacity and mobility, understanding the depth sequence distribution of mobile CP and its speciation in the soil profile is critical in assessing total P (TP) loss to protect the water quality of adjacent water bodies. In this study, physicochemical properties of water-extractable colloids (WECs) from the soil profile at 0-180 cm were characterized using conventional wet chemical analysis. Solution P-31 nuclear magnetic resonance spectroscopy (NMR), P and Fe K-edge X-ray absorption spectroscopy, and transmission electron microscopy were also used to understand P speciation and mineralogy of CP. Percent recovery of WECs per bulk soil increased more than three times with increasing depth. Considering mildly alkaline pH of pore water and negative zeta potential (-21 ± 4 mV) of WECs (size: 1.65 ± 0.45 µm), the transport of P rich WECs (TP: approximately 210-700 mg kg-1) were facilitated from surface to subsoils. Generally, TP in WEC decreased with increasing depth. Interestingly, WECs in subsoil contain organic P (OP) as much as 60 mg kg-1. NMR analysis clearly showed the presence of OP monoesters, OP diesters, and orthophosphate in these particles. Both orthophosphate and OP species interacted with iron oxyhydroxides, calcite, and aluminol functional groups of gibbsite and or phyllosilicates. The study showed the availability of WECs from surface to subsoils that carry orthophosphate as well as OP in legacy P impacted agricultural soils in the Midwestern U.S.


Assuntos
Fósforo , Solo , Agricultura , Fósforo/análise , Qualidade da Água , Espectroscopia por Absorção de Raios X
20.
Chemosphere ; 286(Pt 1): 131594, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34346321

RESUMO

The situation of imbalance application of nitrogenous fertilizers in maize production is a serious issue in China, and excessive nitrogen (N) application is hazardous to sustainable agricultural production and environment. In this experiment, two biochar levels (C0: 0, C1: 2 %), three different N rates (N1: 50, N2: 100, and N3: 200 mg kg-1), and two fertilization methods (T: traditional N fertilizer application mode and D: deep N fertilizer placement mode) were set up to study the response of different treatments on maize yield, N uptake, and N use efficiency. Herein, we found that fresh and dry biomasses were increased by 292 % and 283 % under C1N3 treatment with the deep application of N fertilizer compared to the control treatment (without nitrogen fertilizers and biochar). According to structural equation modeling (SEM), soil physical and chemical properties, N component and C component in different soil layers were associated with biochar and N fertilizer treatment, especially at 20-40 depth. The combination of N fertilizer and biochar application promoted the effects of biochar on the improving NUE of plants. The biochar alleviated the loss of soil nitrogen (from 52.00 to 25.94 %) under traditional N fertilizer application. Overall, excessive input of N fertilizer not only promotes the growth of crops but also causes a waste of resources and environmental pollution. We suggest that combined application of biochar and N fertilizer could significantly reduce N loss, and improve root growth and N uptake, resulting in improving NUE by improving soil environment (pH, SOM, EC) and adjusting soil C/N component.


Assuntos
Fertilizantes , Solo , Agricultura , Carvão Vegetal , Fertilizantes/análise , Nitrogênio/análise
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