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Comparative environmental impact assessments of green food certified cucumber and conventional cucumber cultivation in China

Published online by Cambridge University Press:  29 May 2017

Fang Wang
Affiliation:
College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
Yuexian Liu*
Affiliation:
College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
Xihui Ouyang
Affiliation:
Beijing Green food office, Beijing Municipal Bureau of Agriculture, Beijing 100029, China
Jianqiang Hao
Affiliation:
Beijing Green food office, Beijing Municipal Bureau of Agriculture, Beijing 100029, China
Xiaosong Yang
Affiliation:
College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
*
*Corresponding author: liuyuexian@ucas.ac.cn
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Abstract

The need to ensure food safety has been recognized in China and the ‘Green Food’ system is used to restrict the use of chemical fertilizers and pesticides in its certified products. There has been limited study of the environmental impacts associated with the production of green food certified (GFC) products in China. In this study, life cycle assessment was used to evaluate environmental impacts of GFC cucumber cultivated under a greenhouse system in the suburbs of Beijing relative to conventional cultivation (CON), with the aim of identifying the key areas of potential environmental burden in cucumber cultivation. Eight environmental impact categories are considered, including global warming potential, energy depletion (ED), water depletion, acidification potential, aquatic eutrophication (AEU), human toxicity (HT), aquatic eco-toxicity (AET) and soil eco-toxicity (SET). Results showed that the environmental index of the GFC cucumber system was higher than that of the CON cucumber system. SET, EU and ED were identified as the main potential environmental impacts in cucumber systems, largely caused by fertilizer use on the farm. The potentials of HT and AET in GFC cucumber were lower than those in the CON system, mainly due to the reduced use of chemical pesticides. The agricultural input of plastics was the main contributor to energy depletion in both cucumber cultivation systems. Potential approaches to mitigate the environmental impacts of cucumber cultivation include increasing the fertilizer use efficiency, avoiding use of animal manure with high heavy metal content and recycling of plastics under the GFC cultivation system.

Type
Research Paper
Copyright
Copyright © Cambridge University Press 2017 

Introduction

With the economic growth and expansion of urban centers, urban consumers have indicated increasing concerns for food quality and safety. In addition, the frequent outbreaks of foodborne illness in China have highlighted the urgent need for food certification systems to enhance food quality and ensure safety (Yu, Reference Yu2012). In China, there are currently three different food certification systems: Safe Food Certification (SFC), Green Food Certification (GFC) and Organic Food Certification (OFC). These systems have been adopted to satisfy the demands of domestic consumers with higher income for higher quality products and to pursue a path toward zero synthetic chemical input (Scott et al., Reference Scott, Si, Schumilas and Chen2014). The definition and certification logos of SFC, GFC and OFC are shown in Fig. 1. Among these, GFC is more stringent than SFC, but less stringent than OFC. The SFC and GFC certifications are unique to China (Liu et al., Reference Liu, Langer, Høgh-Jensen and Egelyng2010) and are managed by governmental agencies under the Ministry of Agriculture.

Figure 1. Food certification system in China (modified from Yu et al., Reference Yu, Gao and Zeng2014).

The GFC system has been implemented in China since the 1980s. During 2011–2015 there were 9579 enterprises and 23,386 products under GFC. The output of GFC produce increased from 6.3 to 101 million tons between 1997 and 2014, and the land area under GFC expanded from 2.14 million hectares in 1997 to 17.3 million hectares in 2015 (Chinese Green Food Development Center, 2015), accounting for 14% of the farmland in China. This suggests that the GFC system has been widely accepted in China, particularly by producers. It is generally believed that the development of GFC products could be driven by multiple motivations such as increased environmental sustainability, reduced food-borne diseases and increased farmer income (Lu, Reference Lu2005; Sanders, Reference Sanders2006; Yu et al., Reference Yu, Gao and Zeng2014).

To date, studies on ‘Green Food’ have mainly focused on economic impacts, such as economic yields and consumers’ willingness to pay (WTP). For example, Yang (Reference Yang2006) found that the yield of GFC tomatoes was significantly higher than that of conventional tomatoes, while that of GFC cucumber was significantly lower. Likewise, the WTP for ‘Green Food’ was investigated by Yu et al. (Reference Yu, Gao and Zeng2014), who found that age and income were important for the WTP. Younger people with high monthly family income preferred ‘Green Food’. There were regional differences in consumer preference for GFC food between large cities and rural areas. Consumers in China, on average, were willing to pay 47% more for GFC vegetables and 40% more for GFC meat than for their conventional counterparts.

Numerous reports are available in the literature on environmental impact assessment for organic food production, such as greenhouse gas emissions from organic dairy farms (Flessa et al., Reference Flessa, Ruser, Dorsch, Kamp, Jimenez, Munch and Beese2002; Olesen et al., Reference Olesen, Schelde, Weiske, Weisbjerg, Asman and Djurhuus2006), energy use efficiency in organic cultivation (Pimentel et al., Reference Pimentel, Berardi and Fase1983; Gündogmus, Reference Gündogmus2006; Hoeppner et al., Reference Hoeppner, Entz, McConkey, Zentner and Nagy2006; Kaltsas et al., Reference Kaltsas, Mamolos, Tsatsarelis, Nanos and Kalburtji2007) and integrated environmental assessment in organic cultivation (Liu et al., Reference Liu, Langer, Høgh-Jensen and Egelyng2010; He et al., Reference He, Qiao, Liu, Dendler, Yin and Martin2016). In many such studies, life cycle assessment (LCA) is used to evaluate the environmental impacts of different production systems because it takes all relevant impacts occurring during the entire life cycle into account (Guinée et al., Reference Guinée, Gorrée, Heijungs, Huppes, Kleijn, de Koning, WegenerSleeswijk, Suh, Udo des Heas, Bruijn, Duin and Huijbregts2002; Baumann and Tillman, Reference Baumann and Tillman2004). It allows quantification and estimation of the environmental impact of food and agricultural products at different scales, such as at the farm gate (Milà i Canals et al., Reference Milà i Canals, Burnip and Cowell2006) and across the whole production chain (Knudsen et al., Reference Knudsen, Yu-Hui, Yan and Halberg2010; Liu et al., Reference Liu, Langer, Høgh-Jensen and Egelyng2010). It also facilitates the identification of approaches to mitigate the environmental impacts associated with different production systems (Cellura et al., Reference Cellura, Longo and Mistretta2012; Torrellas et al., Reference Torrellas, Antón, López, Baeza, Parra, Munoz and Montero2012).

After more than two decades of the development of GFC, very few studies have been conducted on exploring the environmental impacts of GFC products in China, from the perspective of the use of agricultural inputs. The objective of this study was to assess the environmental impacts of the GFC cucumber in China, using LCA. The specific aims were: (1) to analyze the differences on the environmental impacts of GFC cucumber compared with conventional (CON) cucumber cultivated in a Beijing suburb; (2) to identify processes that are major contributors to the environmental burdens of agricultural inputs in greenhouse cucumber cultivation; and (3) to discuss options for mitigating environmental burdens associated with the production systems.

Materials and Methods

Data collection

This study was conducted in greenhouse cucumber farms in the Beijing suburb from 2012 to 2013. The GFC cucumber production in this study included 13 farms distributed in the Shunyi and Miyun

Districts and the CON cucumber production included 30 farms distributed across the following nine districts: Shunyi, Miyun, Fangshan, Haidian, Changping, Yanqing, Daxing, Tongzhou and Pinggu district (Fig. 2)

Figure 2. Distribution of the two types of cucumber cultivation systems within the Beijing suburbs, China.

An inventory of production data, emissions and applied resources was compiled for the cucumber cultivation system. Data on agricultural inputs in both cucumber cultivation systems were obtained via questionnaire-based interviews with farmers (Table 1) and based on farmers’ work schedule (Table 2). These data indicate that the two cucumber production systems differed in types and amounts of pesticides and fertilizers used and in other practices. The materials used to construct the greenhouse were not considered because they were similar between the different cucumber cultivation systems.

Table 1. Agricultural inputs and yield for cucumber cultivated in GFC and CON systems in the Beijing suburbs, China.

Table 2. Field operations in GFC cucumber and CON cucumber cultivated in the Beijing suburbs, China.

Functional units and system boundary

The functional unit for analysis was one metric ton of cucumber for direct human consumption, focusing only on cucumber cultivation. Consequently, the system boundary included in the LCA stages was from the cradle (agricultural input production from raw materials) to the farm gate (Fig. 3).

Figure 3. System boundary of the cucumber cultivation system.

Life cycle inventory (LCI)

The LCI analysis encompasses all the resources and associated emissions and relates them to the defined functional unit of the specified system.

Fertilizers

Based on the survey results, a wide variety of chemical fertilizers and animal manure were used during cucumber cultivation in both CON and GFC system. Direct losses from fertilizer application consisted of ammonia (NH3), nitrous oxide (N2O) and mono-nitrogen oxide (NOx) emissions into air, nitrate (NO3 ) leaching to groundwater and phosphorus (P) loss into surface water. The addition of heavy metals into agricultural soil, surface water and groundwater was also taken into account. The atmospheric N2O emissions were determined based on guidelines proposed by the Intergovernmental Panel on Climate Change (IPCC) (IPCC, 2014). According to these guidelines, the application of 100 kg of nitrogen (N)-based fertilizers emitted 1.25 kg of N2O into the air. The average amounts of NOx and NH3 emitted into air were estimated as 2 and 13.23% of the total N-based fertilizer according to Galloway et al. (Reference Galloway, Schlesinger, Levy, Michaels and Schnoor1995) and Zhang et al. (Reference Zhang, Luan, Chen and Shao2011). It was assumed that 30% of total N-based fertilizers leached into groundwater in the form of NO3  (Erickson et al., Reference Erickson, Cisar, Volin and Snyder2001). The P loss was 0.2% of the inputs from chemical or organic P fertilizers (Wang et al., Reference Wang, Wu, Liu and Bao2007).

Heavy metals including cadmium (Cd), lead (Pb), copper (Cu) and zinc (Zn) from organic manure and chemical fertilizers were added into the soil as a result of fertilization. Estimations of heavy metal contents in the different types of fertilizers applied in the present study are listed in Table 3. Heavy metals contained in organic manure and chemical fertilizers were estimated according to Bai et al. (Reference Bai, Zheng, Li, Pen and Li2010) and Chen et al. (Reference Chen, Ni, Li and Sun2009) and heavy metal residues in cucumber were based on the study of Ru et al. (Reference Ru, Zhang, Sun, Wang and Geng2006).

Table 3. Heavy metal contents (mg kg−1) of the different types of fertilizers applied in the studied CON and GFC cucumber farms in the current study.

The fossil energy usage and greenhouse gas emissions at input stage were those associated with agricultural inputs to cucumber cultivation including the manufacture, production and transport of synthetic fertilizers, pesticides and agricultural plastics. Estimation of gaseous emissions such as carbon monoxide (CO), carbon dioxide (CO2), NOx, sulfur dioxide (SO2), methane (CH4) and N2O, from the energy consumption during fertilizer production in China were as shown by Liang (Reference Liang2009).

Pesticides

A range of insecticides and fungicides with different active ingredients were used to control pests and diseases in cucumber cultivation. The inventory data for pesticides were taken from the farmers’ typical work schedule (Table 2). The application and toxicity of bio-pesticides were not considered here because of their small dose and fast degradation. In both the CON cucumber and GFC cucumber systems, the emissions of pesticides to the air were calculated as 10% per kilogram of active ingredient applied (Jager and Visser Reference Jager and Visser1994), 1% to freshwater and 43% to soil (Woittiez et al., 1996; Van Calker et al., Reference Van Calker, Berentsen, de Boer, Giesen and Huirne2004).

Irrigation

In the cucumber cultivation greenhouses, around 60% of the cucumber farmers adopted drip irrigation, while the other farmers still used furrow irrigation under mulch because of the lower cost compared with drip irrigation.

Life cycle impact assessment (LCIA)

LCIA is the phase during which the results of the inventory analysis are further processed and interpreted in terms of environmental impacts and societal preferences. The LCIA comprises a number of compulsory and voluntary steps. It is obligatory to translate the results of inventory analysis into some chosen impact categories, such as climate change or acidification (Wang et al., Reference Wang, Wu, Liu and Bao2007). The LCIA aims to categorize emissions and resources for interpretation. The assessment involves three steps: characterization, normalization and weighting.

Characterization provides indicators of the potential contributions of resource input and emissions output to the impact on the environment. In this study, eight different environmental impacts due to agricultural inputs (including pesticides, fertilizers, diesel and plastics) were taken into account: global warming potential (GWP), energy depletion (ED), water depletion (WD), acidification potential (AP), aquatic eutrophication (AEU), human toxicity (HT), aquatic eco-toxicity (AET) and soil eco-toxicity (SET).

GWP was measured by the CO2 equivalent factors. The GWP (with a time span of 100 years) of CO2, CH4 and N2O is 1, 28 and 265, respectively (IPCC, 2014). The SO2-equivalent factor was used to calculate the AP of the acidification gases (Van Calker et al., Reference Van Calker, Berentsen, de Boer, Giesen and Huirne2004). AEU was used as an indicator for nutrient enrichment in surface water, and in this study, AEU was expressed in phosphate (PO4 ) equivalent factors (Hauschild and Wenzel, Reference Hauschild and Wenzel1998). HT, AET and SET were related to the emissions of the applied pesticides. Characterization factors (CF) for eco-toxicity describe the expected eco-toxicological impacts due to environmental emissions of toxic compound, and the CF values were obtained according to the USES-LCA model, which was measured by 1,4-dichlorobenzene (1,4-DCB) equivalent factors (Huijbregts et al., Reference Huijbregts, Thissen, Guinee, Jager, Kalf, Van de Meent, Ragas, Wegener and Reijnders2000). The impact potential for each of the emission inventories was obtained by multiplying the inventories by the CF corresponding to each effect category (Marigni et al., Reference Marigni, Rossier, Crettaz and Jolliet2002). All the factors considered in this study are shown in Table 4.

Table 4. Equivalent coefficient of emissions inventory for environmental impacts.

Each of the environmental impact potentials was divided by the world per-capita environmental impact normalization factor for the year 2000 to normalize environmental impacts and calculate the environmental index of the two cucumber cultivation systems. Normalization aims to put the LCIA indicator results into a broader context and adjust them to common dimensions (Finnveden & Potting, Reference Finnveden and Potting1999). In this study, normalization values were chosen from Huijbregts (Reference Huijbregts2008), with the world average as reference system and emissions for the year 2000 (Table 5).

Table 5. Normalization values and weights for the different impact categories.

In the weighting step, each normalized indicator was multiplied by a weighting factor (Table 5), which denoted the potential of an impact category to deplete resources, impact natural ecosystems and harm human health. The weighting factors were assessed by 18 Chinese experts in the fields of Environmental Sciences and Agricultural Ecology, based on questionnaires related to the environmental impacts of GWP, ED, WD, AP, EU, HT, AET and SET (Wang et al., Reference Wang, Wu, Liu and Bao2007).

Results and Discussion

Inputs and yields

Agricultural inputs and crop yields in the cultivation systems of GFC cucumber and CON cucumber are shown in Table 1. The yield in the GFC cucumber system (56.3 t ha−1) was 10% lower than that in the CON cucumber system (62.7 t ha−1). However, the amounts of N, P2O5 and K2O applied in the CON system, either in the form of animal manure or synthetic fertilizers, were lower than those in the GFC system (Table 6). We found that cucumber cultivated under the CON system removed more nutrients than the cucumber in the GFC system because of the higher yields (Table 6). Nutrient inputs from manure and synthetic fertilizers far exceeded the vegetable removals indicating that plants do not make use of applied N efficiently. This may be because farmers incur economic loss by applying more N than required to obtain a positive yield response and also because animal manure applied was often free or at a low cost in the Beijing area (Liu et al., Reference Liu, Langer, Høgh-Jensen and Egelyng2010). With excessive fertilization, the yield and quality of cucumber (e.g. the content of vitamin C, soluble protein, soluble sugar etc.) could decrease (Yan et al., Reference Yan, Zou, Dong, Li, Zhang and Wang2009). This seems not to comply with the principle of Green Food production with more safe and nutritious agricultural products (Paull, Reference Paull2008).

Table 6. Types of fertilizers and nitrogen (N) nutrient surplus status in different cucumber production systems.

1 The value of N deposition was 28.0 kg per (ha·year) (Zhang et al., Reference Zhang, Gao, Zhang, Wang, Sui and Zhang2012).

2 N content in mature pear is 0.47% (The National Agricultural Technology Extension Service Center, 1999).

3 NBI (Nutrient Balance Index), equals to N Input/N output in this case sourced from (Lu et al., Reference Lu, Chen, Zhang and Jia2008).

Nutrient balances

Table 6 shows the differences in the types and amounts of N fertilizer applied, and the N nutrient surplus status in the different systems. It is clear that N input through synthetic fertilizers and animal manure was higher in the GFC system than in the CON system. The surplus of N per hectare and the nutrient balance index (NBI) was 18 and 10% higher in GFC compared with CON system, respectively. Consistent with this, Zou et al. (Reference Zou, Yang, Tao and Wang2004) also found that the N input was 8.4 times higher than the uptake in the cucumber cultivated in the greenhouse. Excessive use of N causes these intensive production areas to be particularly sensitive to NO3  leaching (Power and Schepers, Reference Power and Schepers1989; McPharlin et al., Reference McPharlin, Aylmore and Jeffery1995) and could lead to an excessive soil N load and subsequent environmental burden if the use of synthetic fertilizer N exceeded 500 kg ha−1 and the value of the NBI was above 2.5 (Zhang et al., Reference Zhang, Tian, Zhang and Li1995). Zhang et al. (Reference Zhang, Tian, Zhang and Li1996) reported that over fertilization in North China led to high concentrations of NO3  in groundwater and drinking water (average of 68 mg l−1) and lower crop N recovery (less than 40%) in some areas. Multiple vegetable cropping is common in the suburbs of Beijing. Potential annual nutrient accumulation is therefore likely to be higher than shown in Table 1, suggesting that the situation of surplus N and thus environmental burden may be more serious in actual greenhouse cucumber cultivation.

Environmental index of different cucumber systems

The environmental index values for GFC and CON cucumber cultivation were obtained after normalization and weighting. The environmental impact index of 0.39 for GFC cucumber cultivation was 2.2 times higher than that for CON cucumber cultivation (0.17). SET was the main contributor to the environmental impacts, accounting for 49 and 65% in CON and GFC cucumber cultivation systems, respectively (Fig. 4). AEU was the second contributor, accounting for 33% in the CON and 24% in the GFC system, respectively, followed by ED (5% in the GFC and 10% in the CON system, respectively).

Figure 4. Contribution of different potentials (SET, AEU, ED, AP and other potentials which including WD, GWP, HT and AET) to environmental index in GFC and CON system.

Contribution of agricultural inputs to environmental impacts

The environmental impact potential of SET in the GFC system (17.26 kg 1,4-DCB-eq) was two times higher than that in the CON system (5.86 kg 1,4-DCB-eq), which is mainly caused by the input of heavy metals and pesticides. Heavy metal residues (Cu, Zn, Cd, Pb) in the soil had a larger effect on SET, accounting for 97% in the GFC system and 88% in the CON system, respectively (Fig. 5). Heavy metal accumulation in the soil could be due to the large amounts of fertilizers applied in the agricultural soils (Atafar et al., Reference Atafar, Mesdaghinia and Nouri2010; Wang and Li, Reference Wang and Li2014). Animal manure, especially swine and chicken manure, has higher heavy metal content compared with other animal manure (Table 3). The amount of animal manure used in the GFC system was 25% higher than that in the CON system (Table 6). With the increased application of manure, the risks of SET and thus, HT may increase accordingly (Wang and Li, Reference Wang and Li2014). Huang et al. (Reference Huang, Xu, Zhang and Yang2007) found that the total concentrations of Cu and Zn in cucumber-grown greenhouse soils exceeded the second rank of the national farmland soil environmental standard after 10 and 15 years of continuous application of swine manure at 150 m3 per (ha·year), respectively. Pan et al. (Reference Pan, Chen and Bu2012) also found that greenhouse soils had a strong ability to accumulate heavy metals from animal manure, especially Zn and Cd with concentrations of 203 and 1.48 mg kg−1, respectively, in the 0–20 cm soil layer. Among the three kinds of livestock and poultry manures, swine manure caused the most soil pollution.

Figure 5. Contribution of agricultural inputs (manure, fertilizer application, fertilizer production and other inputs including pesticides production, pesticides application, diesel and agriculture film production) to environmental impacts in GFC/CON system.

Compared with the CON system, the potential for AEU was 37% higher in the GFC cultivation system, mainly as a result of the leaching of NO3 , volatilized NH3 during application of synthetic fertilizers and animal manure on farms and leaching of fertilizers off farm. Synthetic fertilizer application on the farms was the main contributor to aquatic eutrophication with the percentage of 50% of CON cucumber and 60% of GFC cultivation system.

The application of animal manure represented 28% of the AEU potential of the GFC system and 40% in the CON system. With regard to the emission level, NH3 and NO3  released from cultivation contributed 47 and 32%, respectively, to the AEU potential in the GFC system. Moreover, NH3 accounted for 48% and NO3  for 33% of AEU in the CON cucumber cultivation. This shows that AEU potential was dominated by NH3 volatilization and NO3  loss during the cultivation stage. Similar results were found in tomato cultivation (He et al., Reference He, Qiao, Liu, Dendler, Yin and Martin2016) and in wheat production in China. The TN and TP in fertilizers were the leading factors for eutrophication and the ratio of TN to TP was significantly positive correlated to eutrophication of water body (Yu et al., Reference Yu, Liu, Zhong and Yao2009). The other factors, such as chemical oxygen demand (COD) and biochemical oxygen demand (BOD), had some effects on the eutrophication.

ED in the GFC system was 10% higher than the CON cucumber cultivation, mainly caused by the production of agricultural inputs. Among these, the production of plastics was the main contributor to energy depletion in the greenhouse cucumber cultivation systems, accounting for nearly 99% both in the GFC system and CON system. The plastics were used in the greenhouse to control weeds and maintain an appropriate soil temperature for seedlings. The second contributor was the production of synthetic fertilizers. The ED from the production of synthetic fertilizers in the GFC system was 47% higher than that in the CON system due to more synthetic fertilizers used in GFC system. Liu et al. (Reference Liu, Langer, Høgh-Jensen and Egelyng2010); He et al. (Reference He, Qiao, Liu, Dendler, Yin and Martin2016), and Duan (Reference Duan2007) also showed that the demand for non-renewable energy resources for the farming system mainly originated from the production of agricultural materials, particularly plastics, fertilizers and pesticides.

Since large amounts of N fertilizers were used in the cucumber cultivation, correspondingly large amounts of N2O were emitted into the air. In this study, N2O contributed 30% of GWP in the GFC system and 35% in the CON system, respectively. Other studies have also shown that N2O emissions dominated the greenhouse effect in wheat production due to the application of N fertilizer, accounting for a significant portion (59%) of the total GHG emissions (Biswas et al., Reference Biswas, Graham, Kerry and John2010). Another main contributor to the GWP was CO2 emissions from the fertilizer production, which accounted for 65% in the GFC cucumber system and 57% in the CON system. This result was in consistent with other reports (Liu et al., Reference Liu, Langer, Høgh-Jensen and Egelyng2010), which showed that GHG emissions from input stages in the pear production systems were mainly due to the GHG emission associated with production of synthetic fertilizers. The total CO2 emission from pesticides and plastic production had a minor contribution to GWP, only accounting for 0.7 and 1% in the GFC system and CON system, respectively. Generally, the GWP in GFC system (204.34 kg CO2-eq) was higher than that in the conventional cucumber system (115.25 kg CO2-eq).

The potentials of HT and AET were dominated by the use of chemical pesticides. In the CON cucumber cultivation system, HT potential and AET potential were 0.0476 kg 1,4-DCB-eq t−1 and 0.095 kg 1,4-DCB-eq t−1, respectively. In contrast, these values were 0.0344 kg 1,4-DCB-eq t−1 and 0.071 kg 1,4-DCB-eq t−1, respectively, in the GFC cucumber system. The potentials of toxicity in the GFC system were lower than in the CON system.

Options for Mitigating Environmental Burdens of Greenhouse Cucumber Cultivation

This LCA study showed that fertilizers represent major environmental burdens in cucumber greenhouse cultivation. The amount of N input from fertilizers in the CON system was lower than that in the GFC system, but we observed higher yields in the CON system. This implies that there are changes to fertilizer management practices that would be valuable for reducing the environmental impacts of greenhouse cucumber production in the Beijing area. Animal manure with high concentrations of heavy metals such as pig/chicken manure should be avoided in the greenhouse vegetable cultivation. Based upon the Green Food-Fertilizer application guideline (Ministry of Agriculture, 2013), synthetic N fertilizer use in the GFC system could be reduced to half that used in CON system without a penalty in yield.

Both research and extension efforts are necessary to help farmers to increase fertilizer use efficiency and thereby reduce environmental burdens associated with the use of fertilizers. Yan et al. (Reference Yan, Zou, Dong, Li, Zhang and Wang2009) found that the optimal fertilization rates for cucumber cultivation in the Beijing area were 487.84 kg N ha−1, 305.47 kg P2O5 ha−1 and 318.02 kg K2O ha−1, which are considerably lower than the rates of the GFC and CON cucumber production systems shown in Table 1. If fertilizer inputs were halved in these two greenhouse cucumber systems by enhancing their use efficiency, the soil eco-toxicity, acidification and aquatic eutrophication potentials would be reduced considerably. Moreover, sustainable agriculture practices, such as crop rotation, use of legumes, mulching, application of green manure and physical trapping, might be adopted to increase fertilizer use efficiency as well as to control soil pests.

In these two cucumber cultivation systems, chemical pesticides contributed fewer toxicity potentials in the GFC system than in the CON system. Additionally, ecological measures such as crop rotation, light traps and color plate traps could be used to control pests to reduce pesticide requirements. Furthermore, weed control by farmers would be a more feasible practice instead of plastics, which could deplete the energy during the process of plastics production.

Conclusion

Green food is well recognized in China among consumers with concerns about food safety and environmental pollution. Comparing LCA data of the cultivation of GFC cucumber and CON cucumber, this study showed that there were lower toxicity potentials caused by pesticides under the GFC cultivation. From this perspective, consumers may prefer the GFC cucumbers because of their lower risk of pesticide residues. However, the overuse of fertilizers has caused negative effects from an environmental perspective and this is particularly the case for the GFC system, which uses more fertilizer overall. The application of animal manure has particularly high associated risks and higher amounts of animal manure are applied in the GFC system than the CON system. This indicates that the amounts of animal manure used should be limited in the GFC system, although the use of animal manure is largely a result of the current restrictions on chemical inputs in the cultivation of GFC products. More effort should be made to help farmers to use fertilizers more efficiency and thus reduce fertilizer use overall. In addition, further studies are recommended to take the environmental aspects into account together with economic costs and nutritional aspects to fill the gaps on integrated effects of green food production and consumption in China.

References

Atafar, Z., Mesdaghinia, A., and Nouri, J. 2010. Effect of fertilizer application on soil heavy metal concentration. Environmental Monitoring and Assessment 160:8389.Google Scholar
Bai, L.Y., Zheng, X.B., Li, L.F., Pen, C., and Li, S.H. 2010. Effects of land use on heavy metal accumulation in soils and source analysis. Scientia Agriculture Sinica 43(1):96104.Google Scholar
Baumann, H. and Tillman, A.M. 2004. The Hitch Hiker's guide to LCA. In: An Orientation in Life Cycle Assessment Methodology and Application. Studentlitteratur, Lund, 543 p. ISBN 9144023642.Google Scholar
Biswas, W.K., Graham, J., Kerry, K., and John, M.B. 2010. Global warming contributions from wheat, sheep meat and wool production in Victoria, Australia—a life cycle assessment. Journal of Cleaner Production 18(14):13861392.Google Scholar
Cellura, M., Longo, S. and Mistretta, M. 2012. Life Cycle Assessment (LCA) of protected crops: An Italian case study. Journal of Cleaner Production 28, 5662.Google Scholar
Chen, L.H., Ni, W.Z., Li, X.L., and Sun, J.B. 2009. Investigation of heavy metal concentrations in commercial fertilizers commonly-used. Journal of Zhejiang Sci-Tech University 26(2): 2630.Google Scholar
Chinese Green Food Development Center, CGFDC 2015. The status of Green food certified products development in China. Available at Web site http://www.greenfood.org.cn/zl/tjnb/lssptjnb/201610/t20161012_5302734.htmGoogle Scholar
Duan, N. 2007. Fertilizer Enterprise Cleaner Production Audit Guidelines. Xinhua Press, Beijing, p. 3340.Google Scholar
Erickson, J.E., Cisar, J.L., Volin, J.C., and Snyder, G.H. 2001. Comparing nitrogen runoff and leaching between newly established St. Augustinegrass Turf and an alternative residential landscape. Crop Science 41:18891895.Google Scholar
Finnveden, G. and Potting, J. 1999. Eutrophication as an impact category. International Journal of Life Cycle Assessment 4(6):311.Google Scholar
Flessa, H., Ruser, R., Dorsch, P., Kamp, T., Jimenez, M.A., Munch, J.C., and Beese, F. 2002. Integrated evaluation of GHG emissions (CO2, CH4, and N2O) from two farming systems in southern Germany. Agriculture, Ecosystems and Environment 91, 175189.Google Scholar
Galloway, J.N., Schlesinger, W.H., Levy, H.I., Michaels, A., and Schnoor, J.L. 1995. Nitrogen fixation: Anthropogenic enhancement environmental response. Glob. Bio-geochem. Cycles 9:235252.Google Scholar
Guinée, J.B., Gorrée, M., Heijungs, R., Huppes, G., Kleijn, R., de Koning, A., WegenerSleeswijk, A., Suh, S., Udo des Heas, H., Bruijn, H., Duin, R.V., and Huijbregts, M.A.J. 2002. Handbook on the Life Cycle Assessment. Operational Guide to the IsoStandards. Book Series: Eco-efficiency in Industry and Science, Vol. 7. KluwerAcademic Publishers, Dordrecht, the Netherlands.Google Scholar
Gündogmus, E. 2006. Energy use on organic farming: A comparative analysis on organic versus conventional apricot production on small holdings in Turkey. Energy Conversion and Management 47(18–19), 33513359.Google Scholar
Hauschild, M. and Wenzel, H. 1998. Environmental assessment of products. In: M. Hauschild and H. Wenzel (eds). Scientific Background. Vol. 2. Chapman and Hall, London, p. 565.Google Scholar
He, X.Q., Qiao, Y.H., Liu, Y.X., Dendler, L., Yin, C., and Martin, F. 2016. Environmental Impact Assessment of Organic and Conventional Tomato Production in Urban Greenhouses of Beijing City, China. Journal of Cleaner Production, In Press.Google Scholar
Hoeppner, J.W., Entz, M.H., McConkey, B.G., Zentner, R.P., and Nagy, C.N. 2006. Energy use and efficiency in two Canadian organic and conventional crop production systems. Renewable Agriculture and Food Systems 21, 6067.Google Scholar
Huang, Z.P., Xu, B., Zhang, K.Q., and Yang, X.C. 2007. Accumulation of heavy metals in the f our years ‘continual swine manure-applied greenhouse soils. Transactions of the CSAE 23(11):239244. (in Chinese with English abstract)Google Scholar
Huijbregts, M.A.J. 2008. Normalisation in product life cycle assessment: An LCA of the global and European economic systems in the year 2000. Science of the Total Environment 390:227240.Google Scholar
Huijbregts, M.A.J., Thissen, U., Guinee, J.B., Jager, T., Kalf, D., Van de Meent, D., Ragas, A.M.J., Wegener, S.A., and Reijnders, L. 2000. Priority assessment of toxic substances in life cycle assessment. Part I: Calculation of toxicity potentials for 181 substances with the nested multi-media fate, exposure and effects model USESLCA. Chemosphere 41:541573.Google Scholar
Jager, D.T. and Visser, C.J.M. 1994. Uniform System for the Evaluation of Substances (USES). Version 1.0. Ministry of Housing, The Hague.Google Scholar
Kaltsas, A.M., Mamolos, A.P., Tsatsarelis, C.A., Nanos, G.D., and Kalburtji, K.L. 2007. Energy budget in organic and conventional olive groves. Agriculture, Ecosystems and Environment 122(2):243251.Google Scholar
Knudsen, M.T., Yu-Hui, Q., Yan, L., and Halberg, N. 2010. Environmental assessment of organic soybean (Glycine max.) imported from China to Denmark: A case study. Journal of Cleaner Production 18:14311439.Google Scholar
IPCC 2014. Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, UK.Google Scholar
Liang, L. 2009. Environmental Impact Assessment of Circular Agriculture Based on Life Cycle Assessment: Methods and Case Studies. China Agricultural University Press, Beijing, p. 1639.Google Scholar
Liu, Y., Langer, V., Høgh-Jensen, H., and Egelyng, H. 2010. Energy use in organic, green and conventional pear producing systems– Cases from China. Journal of Sustainable Agriculture 34(6):630646.Google Scholar
Lu, W. 2005. Trade and Environment Dimensions in the Food and Food Processing Industries in Asia and the Pacific, A Country Case Study of China. Department of Agricultural Economics, Zhejiang University, Hangzhou.Google Scholar
Lu, S.C., Chen, Q., Zhang, F.S., and Jia, W.Z. 2008. Analysis of nitrogen input and soil nitrogen load in orchards of Hebei province. Plant Nutrition and Fertilizer Science 14(5):858865.Google Scholar
Marigni, M., Rossier, D., Crettaz, P., and Jolliet, O. 2002. Life cycle impact assessment of pesticides on human health and ecosystems. Agriculture, Ecosystems and Environment 93:379392.Google Scholar
McPharlin, I.R., Aylmore, P.M., and Jeffery, R.C. 1995. Nitrogen requirements of lettuce under sprinkler irrigation and trickle fertigation on a Spear wood sand. Journal of Plant Nutrition 18:219241.Google Scholar
Milà i Canals, L., Burnip, G.M., and Cowell, S.J. 2006. Evaluation of the environmental impacts of apple production using Life Cycle Assessment (LCA): Case study inNew Zealand. Agriculture, Ecosystems & Environment 114:226238.Google Scholar
Ministry of Agriculture 2013. Green Food-Fertilizer application guideline. (NY/T 394-2013), China Standards Press, Beijing.Google Scholar
Olesen, J.E., Schelde, K., Weiske, A., Weisbjerg, M.R., Asman, W.A.H., and Djurhuus, J. 2006. Modelling greenhouse gas emissions from European conventional and organic dairy farms. Agriculture, Ecosystems and Environment 112:200220.Google Scholar
Pan, X., Chen, L.K., Bu, Y.Q., et al. 2012. Effects of livestock manure on distribution of heavy metals and antibiotics in soil profiles of typical vegetable fields and orchards. Journal of Ecology and Rural Environment 28(5):518525.Google Scholar
Paull, J. 2008. The greening of China's food-Green Food, Organic Food, and Eco-labelling. Sustainable Consumption and Alternative Agri-Food Systems Conference. Liege University, Arlon, Belgium, p. 114.Google Scholar
Pimentel, D., Berardi, G., and Fase, S. 1983. Energy efficiency of farming systems: Organic and conventional agriculture. Agriculture, Ecosystems and Environment 9(4):359372.Google Scholar
Power, J.F. and Schepers, J.S. 1989. Nitrate contamination of groundwater in North America. Agriculture, Ecosystems & Environment 26(3–4):165187.Google Scholar
Ru, S.H., Zhang, G.Y., Sun, S.Y., Wang, L., and Geng, N. 2006. Characteristics and regularity of heavy metals Cu, Zn, Pb, Cd accumulation in different vegetables [J]. Acta Agriculturae Boreali-Sinica, 14691473.Google Scholar
Sanders, R. 2006. Organic agriculture in China: Do property rights matter? Journal of Comtemporary China 15(46):113132.Google Scholar
Scott, S., Si, Z., Schumilas, T., and Chen, A. 2014. Contradictions in state- and civil society-driven developments in China's ecological agriculture sector. Food Policy 45:158166.Google Scholar
The National Agricultural Technology Extension Service Center 1999. China organic fertilizer nutrients [M]. Agricultural Press, Beijing, China. p. 24200.Google Scholar
Torrellas, M., Antón, A., López, J.C., Baeza, E.J., Parra, J.P., Munoz, P., and Montero, J.I. 2012. LCA of a tomato crop in a multi-tunnel greenhouse in Almeria. International Journal of Life Cycle Assessment 17:863875.Google Scholar
Van Calker, K.J., Berentsen, P.B.M., de Boer, I.M.J., Giesen, G.W.J., and Huirne, R.B.M. 2004. An LP-model to analyze economic and ecological sustainability on Dutch dairy farms: Model presentation and application for experimental farm “de Marke”. Agricultural Systems 82:139160.Google Scholar
Wang, M. and Li, S.T. 2014. Heavy metals in fertilizers and effect of the fertilization on heavy metal accumulation in soils and crops. Plant Nutrition and Fertilizer Science (2):466480.Google Scholar
Wang, M.X., Wu, W.L., Liu, W.N., and Bao, Y.H. 2007. Life cycle assessment of the winter wheat-summer maize production system on the North China Plain. International Journal of Sustainable World 14:400407.Google Scholar
Yan, F., Zou, Z.R., Dong, J., Li, J., Zhang, Z.X., and Wang, Y. 2009. Effects of different fertilization treatment on yield and quality of cucumber in plastics greenhouse. Acta Agriculture Boreali-occidentalis Sinica 18(5):272275, 289.Google Scholar
Yang, J.S. 2006. Economic Studies on the Production and Consumption of Safe Vegetables. China Agricultural Press, Beijing (in Chinese, An Quan Shu Cai Sheng Chan Yu Xiao Fei De Jing Ji Xue Yang Jiu).Google Scholar
Yu, X. 2012. Productivity, efficiency and structural problems in Chinese dairy farmers. China Agriculture Economic Review 4(2):168175.Google Scholar
Yu, J.X., Liu, Y.F., Zhong, X.L., and Yao, J. 2009. Evaluation method of eutrophication in Poyang Lake and its leading factors. Acta Agriculture Jiangxi 21(4):25128.Google Scholar
Yu, X.H., Gao, Z.F., and Zeng, Y.C. 2014. Willing to pay for the “Green Food” in China. Food Policy 45:8087.Google Scholar
Zhang, W.L., Tian, Z.X., Zhang, N., and Li, X.Q. 1995. Investigation of nitrate pollution in ground water due to nitrogen fertilization in agricultural in North China. Plant Nutrition and Fertilizer Science 1(2):8087.Google Scholar
Zhang, W.L., Tian, Z.X., Zhang, N., and Li, X.Q. 1996. Nitrate pollution of groundwater in northern China. Agriculture Ecosystems & Environment 59:223.Google Scholar
Zhang, Y.S., Luan, S.J., Chen, L.L., and Shao, M. 2011. Estimating the volatilization of ammonia from synthetic nitrogenous fertilizers used in China. Journal of Environmental Management 92(2011):480493.Google Scholar
Zhang, L.D., Gao, L.H., Zhang, L.X., Wang, S.Z., Sui, X.L., and Zhang, Z.X. 2012. Alternate furrow irrigation and nitrogen level effects on migration of water and nitrate-nitrogen in soil and root growth of cucumber in solar-greenhouse. Scientia Horticulture 138:4349.Google Scholar
Zou, G.Y., Yang, Z.Y., Tao, A.Z., and Wang, M.J. 2004. Study on nutrient uptake by different vegetable crops with high input of organic fertilizer. Southwest China Journal of Agricultural Sciences 17:227229.Google Scholar
Figure 0

Figure 1. Food certification system in China (modified from Yu et al., 2014).

Figure 1

Figure 2. Distribution of the two types of cucumber cultivation systems within the Beijing suburbs, China.

Figure 2

Table 1. Agricultural inputs and yield for cucumber cultivated in GFC and CON systems in the Beijing suburbs, China.

Figure 3

Table 2. Field operations in GFC cucumber and CON cucumber cultivated in the Beijing suburbs, China.

Figure 4

Figure 3. System boundary of the cucumber cultivation system.

Figure 5

Table 3. Heavy metal contents (mg kg−1) of the different types of fertilizers applied in the studied CON and GFC cucumber farms in the current study.

Figure 6

Table 4. Equivalent coefficient of emissions inventory for environmental impacts.

Figure 7

Table 5. Normalization values and weights for the different impact categories.

Figure 8

Table 6. Types of fertilizers and nitrogen (N) nutrient surplus status in different cucumber production systems.

Figure 9

Figure 4. Contribution of different potentials (SET, AEU, ED, AP and other potentials which including WD, GWP, HT and AET) to environmental index in GFC and CON system.

Figure 10

Figure 5. Contribution of agricultural inputs (manure, fertilizer application, fertilizer production and other inputs including pesticides production, pesticides application, diesel and agriculture film production) to environmental impacts in GFC/CON system.