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Plastic film waste can cause a variety of environmental impacts and pose a significant challenge for the consumer product industry. Understanding the environmental tradeoffs of various end-of-life strategies for plastic film waste is thus important for developing and deploying appropriate sustainable solutions. In this paper, we use life cycle assessment (LCA) to assess the environmental impacts of various plastic film waste treatment systems. We consider four different waste treatment scenarios for plastic films: landfill disposal of mixed waste; incineration of mixed waste; recycling of mixed waste; and recycling of recyclable waste. The results demonstrate a considerable advantage of recycling over landfill disposal or incineration. The main environmental benefit is from the recycle of plastics that can substitute for the production of plastics from virgin materials. From a sensitivity analysis, five key parameters are identified that affect the aggregate environmental impact including mass fraction of films in the waste, recycling rate, utilization rate, waste-to-energy conversion rate, and the type of energy can be substituted by the recovered energy from incineration.

One of humanity's contemporary challenges is continuously satisfying the need for global food and environmental security. Numerous individual reports have emphasized the importance of soil surface plastic mulch (PM) as an auxiliary means of increasing crop yields, but a comprehensive assessment of yields and environmental benefits on a national scale has not been performed. A meta-analysis was conducted to compare PM and no-mulch (NM) cropping patterns in China, the largest plastic film consumer in the world. Overall, PM positively influenced crop yields, particularly in semi-arid regions with medium and high nitrogen (N) input. The mean yield increased by 18% for wheat and 27% for maize; these changes were explained by the capacity of PM to increase water use efficiency (17% for wheat and 30% for maize). Notably, PM always increased greenhouse gas (GHG) emissions, and the mean yield-scaled GHG emissions increased by 32% for wheat and 10% for maize on a countrywide scale. In detail, compared to NM, PM resulted in a 2–113% increase in yield-scaled GHG emissions, which was lower in semi-arid regions with medium and high N inputs. For PM systems, yield-scaled GHG emissions in medium N input decreased by 19–31% compared to high N input. Importantly, the yield-scaled GHG emissions in maize was always lower than in wheat. In future, in order to achieve global food and environmental security, it may be advisable to adopt PM in semi-arid regions with medium N input, especially for maize production, based on managing the tradeoffs among yield increase, yield-scaled GHG emissions, and increase in yield-scaled GHG emissions.

Dryland wheat (Triticum aestivum L.) usually suffers from amplified drought because of the decline in precipitation, and thus conserving soil moisture through mulching with plastic film or straw is inevitable. We carried out a 3-year field experiment to determine the most suitable mulching period and method for dryland wheat production based on grain yield, soil water storage, nitrate-nitrogen (NO3−-N) leaching, greenhouse gas emission intensity (GHGI) and economic profits. The experiment included two main treatments [summer fallow mulching (SFM) and year-round mulching (YRM)], and three sub-treatments [ridge plastic mulching plus furrow seeding (MP + F), whole-field plastic mulching plus bunch seeding (MP), and crop straw mulching (MS)]. The average grain yields for SFM and YRM were statistically similar. The average grain yields for MP + F, MP and MS were 5501, 5733 and 5690 kg ha−1 under SFM, and 5609, 6488 and 6462 kg ha−1 under YRM, respectively. The MS under YRM achieved the highest economic profit of 1587 US $ ha−1 per season. Both the average and yearly soil water contents before wheat sowing for SFM and YRM were statistically similar. However, MS showed greater potential for soil water storage before sowing, followed by MP and MP + F, under both YRM and SFM. For both SFM and YRM, the NO3− –N accumulation in the 0–200 cm soil profile at sowing time was significantly higher than at harvest, thus suggesting that no NO3− –N leaching occurred during the present study. The MS under YRM had the lowest GHGI of 314 kg CO2 eq Mg−1. Therefore, MS under YRM should be recommended to local farmers in dryland areas of China and other similar areas around the world.

Plastic film mulching (PM) has been exploited as a beneficial cropping tool to control weeds and to improve soil conditions in temperate-monsoon climate regions. However, the impact of PM on global warming is not clearly understood because it can increase both net primary production (NPP) and soil organic matter decomposition. In particular, the additional greenhouse gas (GHG) emissions from the film manufacturing industry and from waste disposal processes have not been properly considered. To investigate the influence of PM on GHG fluxes in the entire cropping system, PM and no-mulching treatments were installed under organic and chemical fertilization treatments for maize cultivation. The net global warming potential (GWP) was determined by using two GHG (CH4 and N2O) fluxes and soil carbon (C) stock changes with CO2 equivalents within the entire cropping system. PM significantly increased the net GWP by 95 and 35% compared to no-mulching under the organic and chemical fertilization treatments, respectively, whereas most of the net GWP (88–91%) was affected by the GHG flux of the inner cropping boundary. In the cropping process, an average 83 and 91% of the net GWP was influenced by the decrease in the soil C stock in the organic and chemical fertilization treatments, respectively. In contrast, organic fertilization was effective in decreasing the net GWP under the same mulching system due to the reduced soil C stock. PM increased maize grain yield by an average of 52 and 70% compared to no-mulching in the organic and chemical fertilization treatments, respectively, and PM decreased the GHG intensity (GHGI), which implies a net GWP per grain yield of 20 and 30%, respectively, compared to no-mulching. In conclusion, PM can be an effective tool to reduce the GHGI compared to no-mulching; however, PM was more effective in the chemical fertilization treatment than in the organic amendment treatment.

Intercropping is reported to enhance crop production and be a better use of land, thermal radiation and nutrients in many areas around the world. However, intercropping is always yield-advantageous, but consumes more water. Meanwhile, the intercropping advantage is usually attributed to the high inputs of resources, which lead to increased carbon emissions. It is unclear whether developing an improved agricultural production pattern could relieve this situation and enhance farming productivity in water-limited arid areas. A field experiment using an improved system was conducted at an arid oasis region in northwestern China in 2014, 2015, and 2016. No-tillage coupled with two-year plastic film mulching and straw retention measures were integrated into intensified strip intercropping, and the effects on the crop yield, water use, and carbon emissions characteristics were determined. A sustainable evaluation index integrating several key parameters related to yield, water use, and carbon emission was created. We found that a wheat/maize intercropping pattern boosted the grain yield by 12.8 and 131.0% compared to the average yield of maize and wheat monoculture, respectively. The intercropping under no-tillage with straw covering and two-year plastic film mulching treatment (i.e., NTSI2) yielded 17009 kg ha−1, an increase of 14.9%, in the three studied years compared to an intercropping pattern with conventional treatment (i.e., CTI). The wheat-maize intercrops produced 5.9 and 113.7% more energy yield than monoculture maize and wheat, respectively, and NTSI2 had a 6.6% greater energy yield than CTI. NTSI2 improved the water use efficiency based on the grain and energy yields by 15.5 and 7.1%, respectively, over the CTI treatment. The carbon emissions of wheat/maize intercropping pattern were 18.9% lower than maize monoculture, and NTSI2 treatment reduced carbon emissions over CTI by 14.7%. Compared with maize monoculture, the wheat/maize intercrops had a 27.2% lower water use efficiency based on carbon emissions, and the NTSI2 treatment was reduced by 14.4% compared to CTI. However, wheat/maize intercropping had a greater carbon emission efficiency of 39.9% than monoculture maize, and the NTSI2 treatment was increased by 34.7% in the three studied years than that of CTI. The wheat/maize intercropping pattern achieved the highest evaluation index among the three cropping patterns evaluated, and the NTSI2 treatment had the highest sustainable index among the four intercropping treatments assessed. Therefore, wheat/maize intercropping of no-tillage with two-year plastic film mulching and straw covering is the most sustainable and effective cropping production pattern in arid Oasis regions.

Recently there has been an increasing concern about plastic mulch film pollution from agricultural production in China. Given the knowledge of plastic mulch film is information-intensive, the lack of information might be the primary constraint for farmers to adopt recycling practices. Additionally, the potential self-selection bias in the information acquisition process raises an empirical challenge in accurately estimating the impact of information acquisition and information intensity on farmers’ adoption behaviors. To this end, this study first creates a propensity-weighted sample and subsequently employs the multi-valued treatment effects model to analyze how information acquisition influences farmers’ recycling choices, using the sample data from Yunnan province China. The results indicate that information acquisition exerts a positive and significant impact on farmers’ recycling choices, where higher information intensity increases the likelihood of recycling plastic film residues. Understanding the role of information acquisition could assist policymakers in focusing on knowledge diffusion when designing programs to facilitate better management of plastic residues and other sustainable agricultural production practices.

Ratoon rice involves the production of a second crop after the previous main crop harvest, originating from the remaining stubble. Plastic film mulching (PM) cultivation is considered a promising technique for improving economic benefits and reducing greenhouse gas intensity (GHGI). However, the effects of the different cultivation practices differences on the GHGI and the net ecosystem economic budget (NEEB) remain unclear. A three-year experiment was performed to measure CH4 and N2O emissions and grain yields, and then comprehensively assess the GHGI and NEEB. Four rice cropping treatments were established in a traditional single rice field: continuously flooded (CF), rainfed (RF), PM, and PM with ratoon rice cultivation (PM + RR). Compared with CF, RF increased N2O emissions by 108% and reduced CH4 emissions and grain yield by 75% and 22%, respectively, resulting in a reduction of NEEB by 1396 CNY ha−1 y−1. Switching from CF to PM, however, decreased annual CH4 emissions by 56% and increased N2O emissions by 358%, resulting in a 51% reduction in GHGI and an 883% increase in NEEB. Under PM, RR further reduced GHGI by 12% and increased NEEB by 18%. Compared with CF, PM + RR not only significantly increased crop yield by 1.32 t ha−1 and NEEB by 4410 CNY ha−1 y−1, but also dramatically decreased GHGI by 57%. These findings indicate that planting ratoon rice under PM can improve NEEB and reduce GHGI, potentially leading to a win-win situation for the environment and growers in water-stressed regions.

In this paper, we comprehensively assess the differences in soil and water conservation tillage technology among different districts: Fenyang and Ji county of Shanxi province, Ansai and Jingbian county of Shaanxi province, and Zhenyuan and Jingchuan county in Gansu province. We use survey data of 1237 rural households of the Loess Plateau on their adoption of the core technology of soil and water conservation tillage (e.g., contour tillage, groove ridge planting, moderate or non-tillage, subsoiling, straw plowing, stubble mulching, plastic film covering). We use the bootstrap test to analyze peasant household horizontal and vertical differentiation directly impacting on soil and water conservation tillage technology adoption. Next, we test risk perception as the mediation role for technology adoption. Finally, we analyze the moderating effect of government subsidies, and government subsidy can compensate for possible risk losses and encourage farmers to adopt soil and water conservation tillage technology. The results are showed the following: (1) The horizontal and vertical differentiation of farmers have a significant positive impact on the adoption of soil and water conservation tillage technology. (2) In the context of horizontal differentiation, risk perception has a positive mediating effect on the adoption of contour tillage, groove ridge planting, moderate or non-tillage, straw plowing, and plastic film covering technology; in the adoption of subsoiling technology, the mediating effect of risk perception differs because of the size of the government subsidies; in the adoption of stubble mulching technology, the mediating effect of risk perception is not significant. In the context of vertical differentiation, risk perception has a positive mediating effect in the adoption of contour tillage, groove ridge planting and straw plowing; and in the adoption of moderate or non-tillage, subsoiling, and stubble mulching, the mediating effect of risk perception is not significant. (3) In the context of horizontal differentiation, the moderating effect of government subsidies is not significant in the adoption of contour tillage, moderate or non-tillage, straw plowing, and plastic film covering; the moderating effect of government subsidies is significant in the adoption of groove ridge planting and subsoiling. In the context of vertical differentiation, the moderating effect of a government subsidies is not significant in the adoption of contour tillage, groove ridge planting, and straw plowing technology; the moderating effect of a government subsidies is significant in the application of plastic film covering technology.

For a long time, nitrogen (N) management for high-yielding maize (Zea mays L.) has been a severe challenge. The N supply must maximize yield while minimizing environmental impact. In response to the above problems, we evaluated different approaches to nitrogen fertilizer management based on grain yield, economic benefits and environmental benefits of spring maize systems from 2017 to 2019 in a semiarid area of northwestern China. The four treatments included solid granular urea with a split application (UR), one-time application of a mixture of controlled release and solid granular urea (CU), straw return with the combination of controlled release and solid granular urea (CUS) and control (CK). From the perspective of agricultural production, compared with the CK, high yields (>15 Mg ha−1) were guaranteed in the other treatments. Considering both the environment and the economy, compared with the UR treatment, the CU treatment not only improved the economic efficiency of maize cultivation (increased by 4.9%–12.1%) but also significantly decreased the net global warming potential (NGWP) and carbon footprint (CF) (decreased by 21.1–21.7% and 17.8–23.1%, respectively). At the same time, the CU treatment optimized the proportions of N2O emissions at different growth stages and reduced the risk of emissions caused by high temperatures and rainfall in the middle and late stages of maize growth. Compared to the CU treatment, although the CUS treatment increased CO2 and N2O emissions (increased by 35% and 51%, respectively), the accumulation of soil organic carbon (SOC) was enhanced by straw return, which offset the negative impact of the increase in greenhouse gas emissions and significantly reduced the NGWP and CF compared to values for the other three treatments (decreased by 51% and 50%, respectively). With a comprehensive consideration of environmental impacts and economic benefits, the combination of solid granular urea (SGU) and controlled release urea (CRU) with the straw return is an environmentally friendly, high-yielding, high-economic benefit and low-emissions production technology for arid and semiarid areas.

Plastic film mulching can deplete soil organic carbon (SOC) stock but increase GHG emissions. But, few research works have focused on combined effect of cultivation techniques and nitrogen applications on the greenhouse gas intensity (GHGI), net ecosystem carbon budget (NECB) and corn production. Therefore, a two years field study was conducted in 2017–2018, using the following six treatments: RP0: plastic film mulching on ridges with 0 kg N ha−1; RP120: plastic film mulching on ridges with 120 kg N ha−1; RP240: plastic film mulching on ridges with 240 kg N ha−1; CT0: conventional flat planting with 0 kg N ha−1; CT120: conventional flat planting with 120 kg N ha−1; CT240: conventional flat planting with 240 kg N ha−1. Finding of our results showed that plastic film mulching considerable reduced (41.3%) GHGI and improved the maize production. The RP240 treatment improved the soil water storage, thus significantly increased carbon breathing loss, NECB, GWP, N2O, and CH4 emissions. In the RP240 treatment increased (21.9%) the net GWP over CT0 treatment, but decreased GHGI, due to increased (40.8%) biomass production. However, under the RP240 treatment the higher WUE (69.5%), biomass and grain yields obtained which may balance the negative ecological impacts associated with climate change. Therefore, the RP240 treatment may be an efficient water-saving agricultural strategy to improve WUE, maize production and reduce the impact of global warming.

As the demand for cereals increases with the growth of the global population, wheat (Triticum aestivum L.) yield needs to be improved, and the environmental impacts of wheat production need to be lessened. Plastic film mulching (PFM) is becoming recognized as a strategy that guarantees the sustainability of water resources and food production. To date, insufficient attention has been paid to examining the carbon (C) footprint of the PFM practice. A six–year field experiment was conducted to identify the effects of PFM with supplementary irrigation and nitrogen (N) fertilizer application on grain yield, greenhouse gas (GHG) emissions and the C footprint of winter wheat production. In comparison with conventional flat planting without mulch (CFP), the PFM strategy increased grain yield by 31.7% (P

For complying with the recently set higher EU recycling targets, the quality parameters of polyolefin recyclates need improvements to enter new sales markets. Consequently, the plastics recycling sector is increasingly confronted with higher demands on the sensory properties of recycled plastics from post-consumer packaging material. The objective of this study was to examine the sensory properties of two different post-consumer film fractions along a conventional recycling process by a combined sensory-analytical approach. Accordingly, sensory evaluations of two post-consumer film fractions, the associated washing water, a washed waste fraction and conventional recycled pellets thereof were performed by an expert panel, followed by the characterization of the underlying odorants by means of gas chromatography-olfactometry and (two-dimensional) gas chromatography-mass spectrometry/olfactometry. Using this targeted approach, in sum, more than 50 odorants were successfully identified along the processing chain. Most dominant was an array of typical metabolites formed by microorganisms such as cheesy smelling short chain carboxylic acids as well as sulphur or nitrogen containing odorants exhibiting, amongst others, garlic-like or fecal smells. Furthermore, two post-consumer film fractions sorted according to a defined geometry showed great similarities in the odor profiles as well as in the odorant composition. The negligible effect of the applied washing and the still high odor pollution of the recycled pellets demonstrate the urgent need for odor removal strategies in this field. Thereby, the chemical structures of the odorants obtained within this study provide key information on potential sources and formation pathways of odorants supporting the development of targeted deodorization methods.

Nitrogen (N) fertilizer application is an essential way to keep the high yielding crop production, but nitrate-N residue in agricultural soils has attracted wide attentions due to its various environmental effects. Understanding the yield formation and its relation to the N uptake and requirement are urgently needed to reduce the nitrate-N residue for plastic mulched wheat production in drylands. A three-year location-fixed field experiment with five N rates was carried out to test the grain yield formation and N use characteristics of wheat and soil nitrate-N response to no mulch (NM) and plastic film mulch (PM) cultivations. Obtained results showed that the PM promoted the wheat growth and had higher maximum grain yield and biomass at the similar N rate, compared to the NM. Although wheat took up much more N from the soils under the PM, its N requirement for 1000 kg grain formation (NR) showed no significant difference from that of the NM, and for management of N fertilization, the same NR can be used for both cultivations in dryland. Nitrate-N content in 0–20 cm top soil (SNC) was found lower under NM than that under PM, but nitrate-N residue in 0–100 cm soil (SNR) showed no significant difference between these two cultivations. The SNR was significantly and linearly correlated with the SNC under both cultivations, and thus the SNC is able to be used to predict the SNR. Therefore, the present work provides a feasible way or an idea to use the top soil nitrate content, wheat grain yield and its N requirement to optimize the N application rates and N fertilizer recommendation for wheat production and soil nitrate-N residue control in dryland.