Comparative Analysis of Economic and Environmental Trade-Offs in Alfalfa Production in China: A Case Study

Abstract

Alfalfa (Medicago sativa L.) plays a crucial role in the revitalization of the dairy industry and grassland agriculture in China. However, regional differences in economic and environmental performance have not been adequately specified or quantified. This study compares alfalfa production in Wuhe County (Southern China) and Ar Horqin Banner (Northern China) by integrating cost–benefit analysis (CBA) with life cycle assessment (LCA). Field data from 22 enterprises were analyzed using one ton of alfalfa hay and a net profit of CNY 10,000 as functional units, over a three-year evaluation period (2017–2019). The assessment encompassed four impact categories: primary energy demand (PED), global warming potential (GWP), acidification potential (AP), and water use (WU). The northern case systems exhibited 67.45% higher production costs but 96.99% greater profitability per ton compared to the southern case, alongside 2.13 × 10⁻² greater environmental impact. Conversely, the southern case systems were less profitable and demonstrated an 18.6% higher environmental impact per CNY 10,000 net profit compared to the northern case. Regional environmental hotspots differed: fertilizer use dominated impact in the south, whereas irrigation and electricity consumption drove burdens in the north. To facilitate a sustainable transition, policymakers should implement region-specific support measures, such as ecological incentives and crop rotation schemes for the south, and water-saving technologies along with renewable energy integration for the north. Farmers and enterprises are encouraged to adopt precision input strategies and climate risk management tools, while researchers should focus on advancing adaptive breeding techniques and optimizing resource utilization. The development of a unified system that integrates economic and environmental metrics is crucial for enabling stakeholders to drive the sustainable transformation of alfalfa production.

1. Introduction

China’s dairy industry faces the dual challenge of increasing both production volume and quality standards. High-profile food safety incidents, such as the 2008 Sanlu milk powder scandal and recent contamination reports, have exposed persistent flaws in raw milk quality control [1]. One critical constraint on milk quality is the inadequate availability of high-quality forage, particularly alfalfa (Medicago sativa L.), a protein-rich feed crop widely regarded as the “king of forage” [2,3].

Alfalfa offers significant nutritional and ecological benefits. Its deep root system enhances drought resistance and soil stability, while its nitrogen-fixing ability reduces dependence on synthetic fertilizers. Given these advantages, alfalfa is essential for supporting the rapid growth of China’s animal husbandry sector. However, domestic alfalfa production has failed to keep pace with rising demand, both in terms of yield and quality. As a result, China remains heavily reliant on imports due to persistent limitations in local production capacity. In 2022, China imported 1.79 million tons of alfalfa hay, reflecting a 0.4% increase in volume and a 36.2% rise in value, amounting to USD 926 million [4]. Although the north dominates national production, it struggles with increasing water scarcity, whereas the south, despite its richer water resources, faces frequent pest pressures and lower yield stability.

The China–U.S. trade war has further exacerbated these challenges. Tariffs and trade barriers disrupted supply chains, driving up the costs of essential imports such as alfalfa. Consequently, China’s dependence on foreign sources for critical forage crops has become a strategic concern [5], highlighting vulnerabilities in its agricultural import structure and emphasizing the urgency of developing domestic self-sufficiency in key areas such as alfalfa production.

In response, national strategies such as the “14th Five-Year Plan for the National Forage Industry” [6], “grain-to-feed” reform [7], and dairy revitalization policies [8] advocate for expanding domestic alfalfa production through regionally adapted, sustainable models. This initiative not only addresses feed supply issues but also aligns with China’s broader goals of agricultural modernization and carbon reduction.

Despite growing interest in sustainable alfalfa systems [9,10,11], little research has examined how regional differences in natural resources affect economic benefits and environmental consequences. Comparative evidence on balancing economic efficiency and ecological sustainability across different climate zones remains scarce [12,13,14]. To address this gap, this study focuses on two representative regions, Wuhe County in Southern China and Ar Horqin Banner in Northern China. By integrating cost–benefit analysis (CBA) and life cycle assessment (LCA), we aimed to evaluate region-specific alfalfa systems and propose strategies to enhance forage self-sufficiency while safeguarding environmental sustainability.

The remainder of this paper is organized as follows. Section 2 reviews relevant literature. Section 3 describes the research design and methodology. Section 4 presents the results. Section 5 discusses policy implications. Section 6 concludes with recommendations for future research.

2. Literature Review

2.1. Economic Potential of Alfalfa Production

Alfalfa is a crucial forage crop within China’s livestock supply chain, particularly valuable in arid regions due to its drought tolerance and adaptability to marginal lands [15]. Studies have demonstrated that alfalfa–maize rotations in Northern China can improve both water use efficiency and farm profitability [16]. In Ningxia, subsurface irrigation combined with moderate nitrogen input significantly increased yield and income [17]. Similar benefits have been observed in Northeast China, where intercropping alfalfa with maize enhanced resilience and profitability during drought years [18]. Research from Gansu indicates that ridge mulching and precise fertilization can improve yield and quality in irrigated zones [19]. Under drip irrigation, harvesting at early bloom stages generates the highest economic return, despite a slight yield reduction in favor of better forage quality. These findings suggest that strategic management, rather than intensive resource inputs, is the key to maximizing profitability, particularly in water-limited regions [15]. Cost–benefit analysis (CBA) is commonly used to assess economic feasibility and to identify trade-offs between costs and benefits.

2.2. Environmental Impacts of Alfalfa Production

In addition to economic benefits, alfalfa cultivation also imposes environmental burdens. In arid zones, high water consumption and fuel use during harvesting are major concerns. Studies indicate that mechanization and irrigation are key environmental hotspots, especially when powered by fossil fuels [20,21]. To quantify these impacts, researchers increasingly rely on LCA, which tracks resource use and emissions across the full production chain from raw material acquisition to product disposal. LCA is useful for identifying interventions that can reduce environmental impacts. For example, in France, switching energy sources significantly lowered the carbon footprint of dehydrated alfalfa. In Northern China, environmental pressures are primarily associated with fertilizer production and electricity use for irrigation. Thus, LCA provides a valuable framework for assessing sustainability and guiding improvements in alfalfa production systems across different regions [10,22,23,24,25,26].

2.3. Integrating Economic Gains with Environmental Sustainability

Although alfalfa brings substantial economic benefits, its production, particularly in arid regions, often relies on intensive irrigation and mechanization, leading to considerable environmental overheads. This highlights the core challenge of balancing profitability with sustainability. The concept of sustainable development, introduced in the 1987 United Nations report Our Common Future, emphasizes the importance of meeting present needs without compromising the ability of future generations to meet theirs [27]. In the agricultural context, this principle demands that yields be increased without degrading soil quality, depleting water resources, or damaging ecosystems. As alfalfa cultivation expands beyond its traditional northern base into the southern regions of China, these environmental challenges are becoming increasingly relevant.

2.4. Research Gaps and Study Contribution

Despite growing interest in alfalfa sustainability, three key research gaps remain. (1) Regional variations in production cost structures and environmental impacts across different climate zones, such as Northern and Southern China, are underexplored. (2) Existing studies often rely on single-objective analyses, limiting the ability to quantify economic and environmental trade-offs. (3) The scalability of region-specific technologies lacks empirical evaluation, reducing their policy relevance.

This study addresses these gaps by integrating CBA with a multi-indicator LCA to compare representative production systems in Northern and Southern China. It aims to identify synergistic strategies under resource constraints, thereby providing a scientific basis for differentiated regional policies. The findings contribute not only to theoretical advancements in cross-regional sustainable forage systems but also offer practical insights for agricultural transitions in dryland regions globally.

Based on the literature review, the following hypotheses are proposed.

Hypothesis 1.

Natural resource endowments determine the cost structure of large-scale alfalfa production. Due to geographic differences, production costs are expected to vary significantly between Northern and Southern China.

Hypothesis 2.

Better environmental endowments are associated with enhanced sustainability, while greater reliance on external inputs reduces environmental performance. Given the south’s comparative advantage in water resources, its alfalfa systems are expected to demonstrate greater sustainability.

3. Materials and Methods

3.1. Study Area and Case Selection

Wuhe County, situated in northeastern Anhui Province along the southern bank of the Huaihe River (Figure 1), lies within China’s transitional climatic zone and is characterized by predominantly alluvial plains. The region experiences a warm, temperate, semi-humid monsoon climate with distinct seasonal variation, an average annual temperature of 14.7 °C, and annual precipitation totaling 896.3 mm. As of 31 December 2022, Wuhe covers 142,860 hectares and supports a registered population of 529,000 residents [28]. Qiushi Grass Industry Corporation initiated a large-scale land consolidation effort by leasing 6666.67 hectares (4.67% of Wuhe County’s total area) across the Zhuding, Toupu, and Xinxiang townships from 17,576 contracted households. This initiative has established the largest alfalfa production base in Southern China, achieving yields comparable to those in the United States and overcoming long-standing cultivation constraints, thus initiating a scalable model for the development of the forage industry.

Ar Horqin Banner, located on the northeastern periphery of Chifeng City in Inner Mongolia (Figure 1), experiences a temperate continental monsoon climate, with a mean annual temperature of 5.5 °C and annual precipitation ranging between 300 and 400 mm. The Banner encompasses 1.43 million hectares and sustains a population of 2.403 million, supported by an agro-pastoral economy and substantial groundwater resources. Land use includes 239,100 hectares of cropland and 561,380 hectares of grassland, producing approximately 500 million kilograms of grain and supporting 2.7 million livestock units annually. A key feature is its 46,700-hectare high-quality forage base, yielding over 650,000 tons of hay annually and forming the largest contiguous alfalfa production system in China. Recognized as the “Grassland Capital of China” in 2013 and designated a “National Alfalfa Planting Standardization Demonstration Zone” in 2017, the region has attracted significant foreign investment. As of 2022, more than 20 multinational agribusinesses, including Simplot (USA), Beijing Green Pasture, and AustAsia Group (Singapore), have established operations, fostering a vertically integrated, ecologically driven agricultural cluster.

This study selects Ar Horqin Banner and Wuhe County as representative case areas for the following reasons.

• Geoclimatic and Production Model Representativeness

Ar Horqin Banner features a dry, cold climate and exemplifies Northern China’s large-scale, irrigation-dependent, and mechanized alfalfa cultivation model. In contrast, Wuhe County, with abundant solar radiation and thermal resources but subject to frequent droughts and floods, represents an emerging southern model of intensive alfalfa cultivation. Anchored by Qiushi Forage Company, Wuhe illustrates the development of a “grain–forage” dual agricultural structure, providing insights into alleviating the structural imbalance of the “north-to-south forage transport” dynamic in China’s forage–livestock system.

2.

Contrasts in Ecological and economic Pressures

Ar Horqin Banner faces ecological challenges such as water scarcity and soil desertification, requiring trade-offs between irrigation intensity and environmental sustainability. Wuhe County, on the other hand, must manage high land prices and the risk of nitrogen loss, balancing food security demands with forage production needs.

In order to provide a comprehensive depiction of alfalfa cultivation practices in both regions, this study adopted an inclusive case-based approach. Data were collected from 21 of the 26 identified enterprises in Ar Horqin Banner, whereas Wuhe County’s analysis is based on its sole enterprise engaged in alfalfa production.

3.2. Methods

Economic benefits were evaluated using the CBA method, based on an analysis of the cost composition of alfalfa production in Ar Horqin Banner and Wuhe County. Specifically, CBA was employed to calculate the production cost and profit margin per ton of alfalfa hay in each case area for comparative analysis. Environmental impacts were assessed using the LCA method. LCA was used to compare the environmental impacts per ton of alfalfa produced in the two case areas, following four key stages: goal and scope definition, inventory analysis, impact assessment, and result interpretation [29].

3.2.1. Cost–Benefit Analysis Method

The CBA method estimates economic inputs and outputs based on monetary units. The major production costs considered included agricultural material costs, mechanical operation costs, transportation costs, labor costs, and equipment depreciation.

The cost components shared between the northern and southern case studies were as follows. Agricultural material costs comprised expenses for seeds, fertilizers, and pesticides. Mechanical costs included operations such as land plowing, sowing, and harvesting. Transportation costs referred to short-distance field transport to storage facilities. Labor costs covered wages for field operations throughout planting and harvesting. Equipment depreciation was based on a five-year straight-line depreciation method [23]. For Wuhe County, additional costs were incurred for silage wrapping and storage associated with Qiushi Grass Industry’s production system. For Ar Horqin Banner, water usage fees and electricity charges for irrigation were incorporated into the cost structure. These cost data mainly rely on the actual visits and questionnaire surveys.

Net income was calculated as the difference between total revenue and total production costs. The profit margin was determined as the ratio of net income to total production costs, with higher ratios indicating stronger economic performance in alfalfa production.

3.2.2. Life Cycle Assessment Method

In accordance with the ISO 14040 standard [30], LCA environmental impact assessment involved four major stages: goal and scope definition, inventory analysis, impact assessment, and interpretation. Its core function is to assess the potential impact of the entire raw material and the energy consumption and environmental emissions of specific products, processes, or services from raw materials, at each stage of product production to final processing. The technical implementation of LCA was conducted via the eFootprint system in the WebLCA online platform (https://www.weblca.net/home, accessed on 7 May 2023).

• Goal and Scope Definition

The goal of this study was to evaluate the environmental impacts associated with alfalfa production from the generation of agricultural inputs through harvesting and transportation to storage. Two functional units were defined: one ton of dry alfalfa hay and CNY 10,000 of net profit. The ‘per ton of dry weight of alfalfa’ unit was chosen because it provides a standardized basis for quantifying environmental impacts such as greenhouse gas emissions and water consumption. The ‘per CNY 10,000 of net profit’ unit was used to assess the environmental performance relative to economic output.

2.

Life Cycle Inventory Analysis

Life cycle inventory analysis quantifies resource consumption and environmental emissions at each stage of the product life cycle. Data collection is the fundamental task, encompassing inputs such as raw materials, energy, and labor, and outputs including intermediate products, final products, emissions, and wastes. This process covers the entire life cycle from “cradle to grave” and is considered the most detailed and critical stage of the LCA. Primary data on agricultural material consumption and mechanical inputs were collected through field investigations. Upstream production data for agricultural materials, including fertilizers and pesticides, were sourced directly from the Chinese Life Cycle Database (CLCD), available on the WebLCA online platform. The primary environmental emissions considered at each stage included nitrogen oxides (NO_x), carbon dioxide (CO₂), carbon monoxide (CO), particulate matter (PM), and other pollutants. Emission values were calculated using correlation coefficients derived from field data and relevant reference literature (

Table 1. Primary data sources for life cycle inventory.

Inventory Items	Data Sources
Agricultural inputs (seeds, fertilizers, pesticides)	Field survey
Background emission factors for agricultural input production	Pesticide Manufacturing Industry Coefficient Manual [31]; Zheng et al. [32]; CLCD [33]
Mechanical inputs	Field survey
Diesel fuel consumption	Hu et al. [34]
Diesel combustion emission factors	IPCC [35]; Fu et al. [36]; Ge et al. [37]; Shang et al. [38]
Fertilizer runoff and leaching factors	First National Pollution Census—Agricultural Pollution Fertilizer Loss Coefficient Handbook [39]; IPCC [40]; Yang et al. [41]; Yu et al. [42]

).

The primary consumption products in the raw material production stage involve agricultural materials, including seeds, compound fertilizers, and pesticides. The principal environmental emissions originate from the upstream production processes of these agricultural materials. During the planting and harvesting stages, the primary consumption product is diesel fuel used by agricultural machinery such as seeders, plows, harvesters, and rakes; the main environmental emissions arise from diesel combustion. In the transportation stage, the primary consumption product is diesel fuel used by transportation machinery during the short-distance movement of products from the field to storage facilities; the major environmental emissions also result from diesel combustion during field transport. Additionally, the production, consumption, and emissions associated with diesel fuels were derived from the China Life Cycle Core Database (CLCD-China-ECER0.8.1). Data on resource and raw material inputs were collected through field surveys. Pollutant emission coefficients were sourced from published literature and relevant manuals. Supplemented by the background database of the WebLCA online platform, specific pollutant emissions for each stage of alfalfa production per ton of functional unit were calculated (

Table 2. Inventory analysis data for alfalfa production.

	Production Area	Southern Case Area			Northern Case Area
Production Stage		Consumption	Emissions		Consumption	Emissions
Raw material	Compound fertilizer	46.97 kg	N2O	300.608 g	19.739 kg	N2O	12.62 g
			P	14 kg		P	2.71 g
			N	617 g		N	25.9 g
	Seed	1.875 kg	CO2	1.081 kg	4.001 kg	CO2	2.307 kg
	Pesticide	0.157 kg	CO2	6.327 g	2.505 g	CO2	100.515 g
Planting	Tiller and seeder	7.245 kg	HC	47.96 g	5.204 kg	HC	34.45 g
			PM	69.665 g		PM	55.446 g
			CO	116.37 g		CO	93.667 g
			NOx	322.758 g		NOx	260.067 g
			CO2	20.221 kg		CO2	16.293 kg
Harvest	Grass cutting	1.459 kg	HC	17.32 g	4.06 kg	HC	48.192 g
			PM	7.704 g		PM	21.437 g
			NOx	77.443 g		NOx	215.505 g
			CO	44.222 g		CO	123.058 g
			CO2	4.523 kg		CO2	8.321 kg
	Grass raking and processing	0.681 kg	PM	5.137 g	—
			NOx	23.78 g
			CO	8.582 g
			CO2	1.491 kg
			HC	9.721 g
Transport	Transport machinery	0.778 kg	PM	8.309 g	0.762 kg	PM	8.138 g
			NOx	38.495 g		NOx	37.704 g
			CO	13.87 g		CO	13.584 g
			CO2	2.411 kg		CO2	2.362 kg
			HC	1.142 g		HC	9.045 g

Note: N₂O = nitrous oxide; P = phosphorus; N = nitrogen; CO₂ = carbon dioxide; HC = hydrocarbons; PM = particulate matter; CO = carbon monoxide; NO_x = nitrogen oxides.

). For each ton of alfalfa produced on the irrigated sandy land of Ar Horqin Banner, 14.755 tons of irrigation water and 220.536 kWh of agricultural electricity are required.

3.

Life Cycle Impact Assessment

Life cycle impact assessment involves integrating numerous environmental emissions and resource consumption data into a set of widely recognized indicators through the qualitative classification and quantitative transformation of inventory data. This process enables the identification and comparison of environmental impacts across the product’s entire life cycle, which is critical for visualizing potential environmental consequences. Currently, no globally unified methodology for impact assessment exists. This study adopts the methodological framework established by the International Organization for Standardization (ISO) and the Society of Environmental Toxicology and Chemistry (SETAC), as proposed in 1991 and 1993, respectively. The main procedural steps of this phase are categorized into impact classification, characterization, normalization, and weighting assessment [38].

• Impact Categorization

Impact categorization refers to the classification of environmental outputs based on different types of environmental effects. Within the life cycle impact assessment (LCIA) indicator module of the eFootprint system, this study utilizes characterized indicators aligned with international standards. The selected categories include primary energy demand (PED), water use (WU), global warming potential (GWP), and acidification potential (AP), in accordance with ISO 14040 and the methodology proposed by J.W. Owen [43].

• Characterization

Characterization involves quantifying the contribution of each emission to a specific environmental impact category. A reference impact factor is selected, and all other factors are converted into equivalent units through the application of equivalency coefficients [44]. In this study, GWP and AP are quantified using CO₂ and SO₂ as reference substances, respectively, while PED and WU are calculated using the cumulative method. The calculation formula [45] is presented as follows:

$$EP(j)={\displaystyle \sum EP{(j)}_i={\displaystyle \sum \left[Q{(j)}_i\times EF{(j)}_i\right]}}$$

(1)

where EP(j) is the total potential value of environmental impact category j; EP(j)_i is the individual contribution of the i-th environmental intervention to category j; Q(j)_i denotes the quantity of the i-th emission associated with impact category j; and EF(j)_i is the equivalency factor that converts the emission Q(j)_i into a common unit for category j.

• Standardization

Standardization facilitates the quantitative comparison of environmental impacts by normalizing results against a uniform baseline, enabling the identification of the most significant impact categories. In this study, the global average environmental impact potential in the year 2000 was used as the normalization reference.

$$NEP(j)={\displaystyle \frac{EP(j)}{ER(j)}}$$

(2)

where NEP(j) is the normalized environmental impact potential of category j; EP(j) is the unnormalized potential environmental impact; and ER(j) is the reference or baseline value used for standardization.

• Weighted Evaluation

Standardized values alone are insufficient to comprehensively reflect the relative significance of different environmental impact categories. Therefore, a weighting process is necessary to integrate multiple impact categories into a single aggregated indicator. In this study, the commonly applied ISCP 2009 [46] weighting scheme was adopted. This method is grounded in the distance-to-target (DtT) principle and aligns with China’s national environmental policy objectives. ISCP 2009 employs impact category classifications broadly consistent with the internationally recognized methodology developed by the Centre of Environmental Science at Leiden University (CML). This ensures methodological consistency while incorporating region-specific weighting factors tailored to China’s sustainability objectives [47]. The weighting procedure was implemented using the eFootprint system, enabling the integration of standardized midpoint scores into a unified environmental impact value.

3.3. Field Survey Data Acquisition

In 2020, systematic field investigations were carried out through on-site questionnaires administered to Qiushi Forage Company in Wuhe County (Bengbu City, Anhui Province, Southern China) and contiguous alfalfa production enterprises in Ar Horqin Banner (Chifeng City, Inner Mongolia Autonomous Region, Northern China). Input–output data covering the period from 2017 to 2019 were collected from 22 large-scale alfalfa production enterprises. Three-year moving averages were calculated to reduce the effects of year-to-year variability in agricultural productivity.

4. Results

4.1. Differences in Economic Cost–Benefit of Alfalfa Production Between the North and South

Figure 2 presents a comparative economic cost–benefit analysis of alfalfa production in the northern and southern cases. Figure 2a displays the absolute cost values for each input category in both cases, highlighting significant regional differences. In the southern case, land rent accounts for the highest proportion of production costs. In the northern case, irrigation represents the most substantial expense, reflecting the region’s reliance on electricity-intensive irrigation systems. Input cost categories in both cases include land rent, seeds, fertilizers, pesticides, machinery (such as harvesters, rakers, tractors, and forklifts), labor, and irrigation. Although land rent in the north is significantly lower (approximately one fifth that of the south), the northern case incurs higher expenditures in other categories. Specifically, input costs exceed those of the south by a factor of 5.76 for seeds, 1.85 for fertilizers, 1.42 for pesticides, 2.41 for machinery, and 35.86 for labor. This difference in land rent arises from distinct land-use strategies. In Wuhe County, Qiushi Forage Company leases high-quality farmland through long-term contracts (with a minimum term of five years), which ensures stable, large-scale cultivation. However, this approach limits flexibility in rental adjustments and contributes to persistently high land costs. In contrast, in Ar Horqin Banner, alfalfa is cultivated on reclaimed sandy land of lower quality, which substantially reduces rental expenses.

Figure 2b presents the relative proportion of each cost category as a share of total production costs, further illustrating regional differences. In the southern case, land rent accounts for 56.81% of the total, followed by wrapping, pressing, fertilizer, and machinery (11.90%, 10.43%, and 9.42%, respectively). In the northern case, which relies on a mechanized and irrigated production system on sandy soil, irrigation is the largest cost item (49.08%), followed by machinery (13.56%), fertilizer (11.52%t), and land rent (ranking fourth). The high cost of irrigation is attributed to the arid climate, where early-season irrigation is essential for seedling establishment and overwintering survival under frequent spring sandstorms. Field research indicates that both cases depend heavily on imported seeds and substantial fertilizer use to sustain yields, which contributes to elevated input costs. In addition, large-scale alfalfa production requires the coordinated use of extensive agricultural machinery across large tracts of land (typically exceeding 66.67 hectares). The wide operational scale and high maintenance requirements substantially increase machinery-related expenditures.

Figure 2c compares total cost, revenue, profit, and profit margin between the two cases. The northern case (Ar Horqin Banner) demonstrates a higher profit margin of 26.79%, compared to 13.60% in the southern case (Wuhe County). These findings are consistent with previous studies suggesting that irrigated systems, such as those employed in the north, generally yield higher economic returns than rainfed systems [17,48]. Overall, the north’s cost, profit, and profit margin are 1.67, 3.30, and 1.97 times those of the south, respectively.

4.2. Differences in Environmental Impacts of Alfalfa Production Between Northern and Southern China

This study adopts the LCA methodology to evaluate the environmental impacts of producing one ton of alfalfa hay in Southern and Northern China across four life cycle stages: raw material production, planting, harvesting, and transportation. The assessment includes four environmental impact categories: PED, WU, GWP, and AP, in addition to an comprehensive impact (CI) indicator.

Figure 3 presents the overall CI values for both cases. The CI value for the southern case is 1.11 × 10⁻², while the value for the northern case is 3.24 × 10⁻², indicating that alfalfa production in the north results in an environmental impact 1.92 times higher than that in the south. Figure 3 also illustrates differences across individual environmental indicators. In the northern case, WU and PED are 5.39 and 2.39 times higher than in the southern case, respectively. The northern case also shows elevated values for GWP and AP, at 1.70 and 1.42 times higher than those in the south.

Figure 4 shows the contribution proportions of PED, WU, GWP, and AP across the four production stages in both cases. Figure 4a presents the contribution distribution in the southern case, where raw material production is the primary contributor to all four impact categories. This reflects the southern case’s heavy reliance on upstream resource inputs, particularly in the manufacturing of fertilizers and pesticides. Figure 4b shows the results for the northern case, where the planting stage contributes the most, reflecting intensive irrigation and field operations. Additionally, the northern case exhibits higher impacts than the southern case in the planting, harvesting, and transportation stages, while raw material production remains the only stage with a higher impact in the southern case.

Figure 5 illustrates the characterization values for each environmental indicator. Figure 5a compares the PED values between the two cases, showing that the northern case consumes 2330 MJ more per ton than the southern region. In the southern case, PED is concentrated in raw material production, mainly due to fertilizer manufacturing and diesel consumption in field machinery. This pattern is consistent with previous findings reported by Wang et al. [49]. In the northern case, PED is driven by electricity-dependent irrigation systems powered by motorized wells and large-scale sprinklers, most of which rely on thermal power. The northern case tends to have higher PED across most stages, except raw material production.

Figure 5b compares WU, indicating that the northern case uses 13,700 kg more water per ton than the southern case. Alfalfa production in the south primarily relies on precipitation, with most water use originating from upstream fertilizer and pesticide manufacturing. In contrast, the north depends on groundwater irrigation due to frequent spring and winter droughts, making the planting stage the most water-intensive. WU in the southern region is slightly higher during raw material production but remains negligible in the other stages.

Figure 5c shows the GWP values, with the northern case exceeding the southern case by 147 kg CO₂ equivalent per ton. Emissions in the south are primarily associated with fertilizer production and nitrogen losses. In the north, GWP is dominated by electricity consumption for irrigation, most of which is supplied by thermal power plants. The northern case records higher GWP in most stages, except for raw material production.

Figure 5d compares AP, revealing that the northern case surpasses the southern case by 0.63 kg SO₂ equivalent per ton. In both cases, emissions of nitrogen oxides and ammonia from fertilizer use are the primary contributors. In the northern case, sulfur oxide emissions and airborne particulate matter from electricity use further increase the AP value. Higher AP values are observed in the planting, harvesting, and transportation stages in the north, while the southern region shows higher AP values only in raw material production.

4.3. Differences in Environmental–Economic Impacts of Alfalfa Production Between Northern and Southern China

Using a benchmark net profit of CNY 10,000, Figure 6 shows the comprehensive CI values for the southern and northern cases, which are 0.927 and 0.820, respectively. The CI value in the south is 1.13 times greater than that in the north. With the exception of WU, the southern case exhibits significantly higher environmental impacts across all other categories. Specifically, the AP, GWP, and PED in the south are approximately 2.32, 1.94, and 1.38 times higher than those in the north, respectively.

In contrast, WU in the north is 1.63 times greater, which is consistent with its greater dependence on irrigation. This reversed trend, in which the southern case has higher PED, GWP, and AP values despite lower absolute impacts, is attributed to the north achieving 2.20 times greater net profit per ton of alfalfa. In both cases, environmental impacts are mainly concentrated in the raw material production and planting stages, with consistent patterns observed across categories.

Figure 7 presents the characterization values of PED, WU, GWP, and AP under the CNY 10,000 net profit benchmark. Figure 7a illustrates PED differences, showing that the southern case consumes 38,300 MJ more than the northern case, which reverses the trend observed on a per-ton basis. This difference is primarily due to the significantly higher energy use in raw material production, which is 9.72 times that of the north, as well as slightly higher PED during harvesting. In contrast, PED during planting and transportation is lower in the south. Apart from harvesting, the stage-level differences remain consistent across both benchmarks.

Figure 7b presents the WU comparison, indicating that the northern case uses 166,000 kg more water than the southern case, a result consistent with the per-ton benchmark. At the stage level, the north records higher WU during planting, harvesting, and transportation. This is especially pronounced during planting, where WU is 108.28 times greater in the north. The southern case only shows higher WU during raw material production.

Figure 7c illustrates the GWP values, showing that the southern case exceeds the northern case by 8450 kg of CO₂ equivalent. This result is contrary to the per-ton comparison. Under the net profit benchmark, the southern region emits more during raw material production (7.43 times higher), as well as during harvesting and transportation. In contrast, the northern region shows higher GWP only during the planting stage.

Figure 7d shows the AP values, with the southern case surpassing the northern case by 71.4 kg of SO₂ equivalent, again contrasting with the per-ton results. The south contributes more to AP across all stages except planting. In particular, AP from raw material production in the south is 8.29 times higher than in the north.

4.4. Sensitivity Analysis

Sensitivity analysis evaluates how a 1% variation in inventory parameters influences environmental impact indicators, thereby identifying key areas for potential improvement [50]. In this study, compound fertilizer application, irrigation, and diesel combustion are identified as the primary contributing processes.

$$Sij=(\mathrm{\Delta }{Y}_i/Y_i)/(\mathrm{\Delta }{I}_j/I_j)$$

(3)

In the southern case (

Table 3. Sensitivity of inventory parameters for key contributing processes in alfalfa production in the southern case (PED = primary energy demand; WU = water use; GWP = global warming potential; AP = acidification potential).

	Sensitivity	PED (MJ)	WU (kg)	GWP (kg CO2 eq)	AP (kg SO2 eq)
Key Processes
Compound fertilizer production		57.80%	80.68%	74.57%	68.41%
Nitrogen-containing element emissions in the field		57.80%	80.68%	36.37%	68.41%
Pesticide		13.89%	17.35%	5.38%	3.48%
Diesel combustion		20.48%	1.42%	13.56%	18.68%

), raw material production and fertilizer application exhibit the highest sensitivity. A 1% increase in compound fertilizer production results in changes of 57.80% in PED, 74.57% in GWP, 68.41% in AP, and 80.68% in WU. Similarly, nitrogen-related emissions from fertilized fields cause equal changes in PED and WU (57.80% and 80.68%, respectively), while also exerting substantial influence on GWP and AP. These findings emphasize that compound fertilizer input and its field application represent critical intervention points for reducing environmental burdens in southern alfalfa production.

In the northern case (

Table 4. Sensitivity of inventory parameters for key contributing processes in alfalfa production in the northern case (PED = primary energy demand; WU = water use; GWP = global warming potential; AP = acidification potential).

	Sensitivity	PED (MJ)	WU (kg)	GWP (kg CO2 eq)	AP (kg SO2 eq)
Key Processes
Compound fertilizer production		10.18%	6.27%	18.37%	20.19%
Agricultural electricity		78.49%	4.71%	71.20%	62.74%
irrigation		0.93%	88.70%	0.79%	0.69%
Diesel combustion		4.81%	0.15%	4.46%	7.83%

), processes undertaken during the cultivation stage, particularly agricultural electricity use and irrigation, show the greatest sensitivity. A 1% increase in electricity consumption leads to a 78.49% change in PED, 71.20% in GWP, and 62.74% in AP. Irrigation parameters have the most significant effect on WU, with a 1% change resulting in an 88.70% variation. Therefore, electricity use and irrigation constitute the main environmental pressure points in northern alfalfa production and should be prioritized for optimization.

5. Discussion

Based on field data from Wuhe (south) and Ar Horqin (north), this study reveals that although the northern region incurs 67.45% higher production costs, it achieves 96.99% greater profitability per ton of yield. In terms of environmental performance, the northern region exhibits a higher total impact index. However, the southern region produces 18.6% more environmental impact per CNY 10,000 of net profit. These findings reflect a trade-off between economic return and environmental burden, highlighting shared challenges in resource utilization and sustainability across both regions.

5.1. Drivers of Regional Differences in Alfalfa Production

The observed economic and environmental differences between the northern and southern cases are primarily shaped by two structural factors: land leasing and irrigation systems. In the southern case, Qiushi Forage Company leases high-quality farmland, resulting in land costs accounting for 56.8% of total production expenses. Additional costs stem from silage processing and fertilizer application, which are intensified by frequent flooding and typhoons in Wuhe. These weather events reduce nutrient retention and necessitate higher fertilizer input. Conversely, the northern case benefits from lower land rent but faces severe spring droughts. To ensure crop viability, irrigation constitutes nearly half of total costs in Ar Horqin, reflecting reliance on groundwater and electrically powered sprinkler systems.

Environmental impact patterns also differ significantly. In the southern case, the primary contributors are compound fertilizer production and nitrogen emissions. In the northern case, water use for irrigation and electricity consumption are dominant sources of environmental pressure. The northern case demonstrates a 2.13 × 10⁻² higher impact per ton, reflecting greater challenges such as groundwater overuse, greenhouse gas emissions, and soil degradation. However, the environmental impact per CNY 10,000 of net profit is 18.6% lower in the north, highlighting the trade-off between production efficiency and sustainability. These regional disparities complicate environmental risk management and underline the urgent need to enhance resource efficiency and reduce pollution. Effective environmental governance is essential to balancing productivity and sustainability.

These findings support Hypothesis 1, confirming that natural resource endowments shape cost structures. The north’s low land costs and high irrigation expenses contrast with the south’s high land rent and minimal water input, reflecting the influence of regional resource conditions. Hypothesis 2 is partially revised. Although the south shows lower absolute environmental impacts, its reduced economic efficiency leads to higher environmental intensity per unit of profit. This supports the view of Ren et al. [51] and Kamran et al. [52], who found that small-scale or low-efficiency systems often bear greater environmental burdens.

Two systemic factors help explain these differences:

The north relies more on mechanization and diesel-powered systems, whereas the south depends on labor-intensive practices and benefits from a climate that reduces fossil energy demand.

• Resource endowment asymmetry: The north faces water scarcity but less land pressure, while the south experiences abundant rainfall but limited land availability.
• Technological path dependency: The north relies more on mechanization and diesel-powered systems, whereas the south depends on labor-intensive practices and benefits from a climate that reduces fossil energy demand.

In addition to regional contrasts, broader influences such as climate, production scale, technological development, and policy frameworks also shape alfalfa production outcomes. Empirical studies indicate that water scarcity increases production costs in the United States [53], whereas the adoption of stress-resistant seed varieties and modern irrigation systems enhances both yield and environmental performance [51,52]. Policy instruments such as the U.S. Farm Bill have facilitated such transitions. In contrast, China’s alfalfa sector faces limitations due to high input costs, low technological uptake, and uneven distribution of subsidies [51].

Policy, regulatory, and socioeconomic disparities significantly affect production costs in Ar Horqin Banner and Wuhe County. Ar Horqin benefits from conditional subsidies, relatively relaxed regulatory oversight, and broader adoption of modern agricultural practices, resulting in higher actual profit margins. Wuhe promotes ecological agriculture, enforces stricter land and environmental regulations, and experiences labor shortages, all of which contribute to elevated costs. Although subsidies are excluded from direct profit calculations due to their conditional nature, enterprises in Ar Horqin often qualify for these supports. By contrast, Wuhe’s high-quality farmland is prioritized for food crops to ensure national food security, rendering alfalfa cultivation ineligible for subsidies and thereby reducing profitability. Labor constraints and differences in land-use efficiency further widen the cost disparity between the two regions.

As climate change accelerates, regional risks are expected to diverge. In the northern region, longer growing seasons may enhance yields, but increased irrigation demands and soil salinization could compromise sustainability. In the southern region, intensified rainfall and humidity are projected to increase nitrogen loss, pest pressure, and forage quality degradation, introducing new environmental and economic challenges.

Influenced by interacting factors, alfalfa production varies significantly across countries. The United States leads the global market through large-scale, technologically advanced operations. Europe prioritizes ecological sustainability within a smaller industry footprint. In contrast, China’s alfalfa sector has experienced rapid growth due to policy support and technological progress. However, it continues to face substantial gaps in germplasm quality, technical capacity, and infrastructure when compared with the United States, Canada, and Europe. Despite these limitations, China retains significant growth potential. Strengthening international cooperation and accelerating the transfer of advanced technologies will be essential to enhancing the competitiveness of China’s alfalfa industry.

5.2. Regional Trade-Offs Between Profitability and Sustainability

Alfalfa production in China exhibits distinct trade-offs between economic efficiency and environmental sustainability across northern and southern regions. In the south, limited land availability and high rental costs constrain profitability. However, favorable climatic conditions and minimal irrigation needs reduce energy consumption and environmental impact per unit, particularly regarding PED and GWP. This positions the southern system closer to ecological agriculture, with higher resource efficiency but lower short-term returns.

In contrast, the north depends on mechanization and intensive irrigation, leading to increased electricity and water use. While this raises environmental pressure and production costs, it supports large-scale operations, high yields, and greater profitability, making the northern system more competitive in industrial forage markets. However, its reliance on resource-intensive inputs exposes it to ecological risks, especially during droughts or energy price fluctuations. It reflects a typical “high-input–high-output–high-impact” development path.

The relationship between economic and environmental performance is shaped by regional characteristics. The south may benefit from diversified planting systems, such as alfalfa–fruit or alfalfa–grain rotations, to improve ecological outcomes. The north should focus on green transformation through water-saving irrigation, stress-resistant varieties, and smart farming technologies.

Region-specific policy support is essential. Ecological farming zones and green subsidies are recommended in the south, while infrastructure investment and clean technology promotion are needed in the north. A unified evaluation framework integrating both environmental and economic indicators should guide producers toward sustainable decision-making.

5.3. Optimizing Alfalfa Production in Northern and Southern China

5.3.1. Southern China

In Wuhe, high land rental costs (56.81%) and fertilizer input (10.43%) are major economic constraints. Compound fertilizer production and nitrogen emissions are identified as key environmental pressures. Sensitivity analysis confirms these as priority intervention points. Two strategies are recommended:

• Intercropping and Integrated Systems: Planting alfalfa alongside wheat or under fruit trees helps distribute costs, enhance nitrogen fixation, and improve soil health. Empirical studies suggest that wheat–alfalfa intercropping enhances microbial activity and boosts yields [54,55,56]. While input costs are reduced through resource sharing, this system requires technical support and policy incentives due to its complexity.
• Seasonal Rotation: Utilizing idle winter farmland (such as post-rice harvest fields) for alfalfa cultivation improves land-use efficiency and reduces fertilizer demand by 20% to 40% [57]. Alfalfa also functions as green manure, enriching soil nutrients and improving rice yields [58]. These practices should be supported by land circulation services, agricultural insurance, and rural credit mechanisms [59].

5.3.2. Northern China

In Ar Horqin, irrigation (49.08%) and machinery use (13.56%) constitute the dominant cost components. Electricity consumption associated with irrigation is the primary environmental pressure. Sensitivity analysis highlights irrigation efficiency and energy use as key leverage points. Two strategies are proposed:

• Smart Irrigation Integration: Develop modular irrigation systems tailored to varied terrain, integrating water, fertilizer, and pesticide delivery. Precision control using internet of things (IoT) technology and subsurface drip systems can enhance input efficiency [60]. Policy support for research, development, and equipment standardization is critical for implementation in fragmented landscapes.
• Climate-Resilient Cultivar Development: Dependence on imported, poorly adapted alfalfa varieties highlights the need for locally bred, drought- and cold-tolerant cultivars [61,62]. Integrating traditional breeding with genome editing, and employing mixed sowing with clover (Trifolium spp.) or timothy (Phleum pratense L.), can stabilize yields and enhance soil resilience [63].

These region-specific strategies offer a pathway to balance economic and environmental goals under diverse agroecological conditions.

5.4. Policy Implications

5.4.1. Recommendations for Government

Governments should establish green procurement standards to encourage leading dairy companies (such as Yili and Mengniu) to adopt low-carbon alfalfa certified through LCA. Support for silage processing using anaerobic fermentation and biogas recovery should be provided through tax incentives. A national-level reserve mechanism for alfalfa silage is also recommended to stabilize market volatility and enhance industry resilience.

In arid northern regions, subsidies should prioritize water-saving technologies (such as drip or micro-spray irrigation), aligned with the Grassland Ecological Protection Subsidy. Tiered water pricing should be linked to actual usage reductions. In regions with groundwater over-extraction, designated redline zones should mandate rotational cropping or fallow periods. The “photovoltaic plus irrigation” model should be promoted and prioritized within national forage development programs.

In the south, where non-point source pollution is more prominent, ecological compensation should incentivize reductions in nitrogen fertilizer use. Eligible enterprises should be granted access to carbon credit markets. The integration of rice–alfalfa rotations into high-standard farmland subsidy programs, along with promotion of weather index insurance, will improve climate risk management and policy targeting.

5.4.2. Recommendations for Farmers and Enterprises

Farmers and enterprises should enhance traceability systems, adopt green procurement practices, and diversify raw material sourcing. Participation in carbon footprint evaluations and sustainability certifications can improve market competitiveness.

Producers in the north are advised to implement water-efficient irrigation, explore dryland cropping systems, and integrate photovoltaic infrastructure to enhance compound returns. Investment in silage processing facilities can strengthen the value chain and improve market leverage.

Producers in the south should adopt precision fertilization and AI-assisted field management. Crop–livestock integration models, such as orchard intercropping or straw–alfalfa rotation, can improve land-use efficiency. Engagement with carbon markets and weather-based insurance schemes can mitigate environmental and economic risks.

5.4.3. Recommendations for Researchers and Innovators

A National Alfalfa Technology Collaborative Innovation Center is recommended to coordinate breeding, equipment development, ecological management, and policy research. Leveraging IoT and big data for nationwide climate risk monitoring will support adaptive responses.

In the north, priority should be given to breeding drought- and cold-tolerant cultivars such as the Zhongmu series, utilizing gene editing and resistance gene mapping. Integrated water and fertilizer systems, including soil moisture monitoring and variable-rate irrigation, will enhance water-use efficiency.

In the south, digital nutrient management platforms based on remote sensing and AI can improve fertilization accuracy while reducing emissions. Further research should focus on microbial agents, bio-organic fertilizers, and ecological safety solutions in acidic and contaminated soils.

5.5. Uncertainties and Limitations

To improve the validity of this case study, Wuhe County and Ar Horqin Banner were purposefully selected due to their contrasting climatic conditions, production systems, and resource endowments. This contrast offers a meaningful basis for comparative analysis of alfalfa production systems. However, the findings derived from these two cases may not fully reflect the diversity of conditions across all alfalfa-producing regions in China.

To reduce interannual variability, the analysis employed average data from 2017 to 2019. While this approach improves result stability, it may obscure short-term fluctuations in productivity and environmental performance. Enterprise-reported data were cross-validated where feasible, although inconsistencies in local data standards and infrastructure may introduce bias.

This study identified fertilizer production and irrigation as the primary contributors to environmental impacts in alfalfa cultivation. Nevertheless, due to limitations in the available data, particularly with respect to input–output dynamics under alternative management practices, it was not possible to simulate scenarios involving reduced fertilizer use or the implementation of water-saving irrigation technologies.

Future studies should broaden the geographic scope and sample size to include additional provinces, particularly in Central and Western China, and adopt longitudinal designs to evaluate sustainability over time. This would enhance the generalizability and policy relevance of the results. Further investigation into the role of regional policy instruments, including subsidies, technical services, and agricultural insurance, could provide more-nuanced insights for adaptive policy formulation.

Research should also prioritize the development of integrated datasets that capture both environmental and agronomic outcomes under varied management strategies. These strategies include precision fertilization, the use of organic amendments, and advanced irrigation technologies such as drip and sprinkler systems. Incorporating such data into scenario-based LCA models will enable a more robust evaluation of trade-offs and co-benefits, thereby informing more effective and sustainable decision-making in alfalfa production.

6. Conclusions

This study compares the economic and environmental trade-offs associated with alfalfa production in Northern and Southern China, using Wuhe County and Ar Horqin Banner as representative case studies. The key conclusions are as follows:

• Economic Performance: The Northnorthern production system, characterized by lower land costs and mechanized operations, achieves a 96.99% higher profit margin despite incurring greater overall costs. In contrast, the Southsouthern system is constrained by high land rent and limited economies of scale, resulting in lower profitability.
• Environmental Performance: On a per-ton basis, the Northnorthern region exhibits higher environmental impacts due to greater water and energy consumption, whereas the Southsouthern region demonstrates better environmental performance. However, when impacts are normalized by economic return, the Southsouth displays 18.6% higher environmental intensity, indicating a trade-off between ecological performance and economic efficiency.
• Recommendations: In the south, efforts should focus on intercropping, land-use optimization, and precision fertilization. In the north, improvements in irrigation efficiency and the development of resilient cultivars are essential. A dual-track policy framework is recommended to address region-specific needs while promoting circular practices, smart technologies, and climate-resilient strategies among producers and enterprises.

Future research should expand regional coverage, adopt long-term sustainability assessments, and integrate policy, economic, and environmental indicators. Such efforts are critical to building a comprehensive evaluation system that supports scenario-based decision-making for the high-quality and adaptive development of China’s alfalfa industry.