Search

Agricultural subsidy policy can improve the planting enthusiasm of rural households by increasing their income. It is of great significance to assess and summarise the effect of the soybean and cotton target price subsidy policy and to determine future policy direction. Using the national rural fixed-observation point socioeconomic survey data from 2009 to 2017, the study employed the difference-in-differences (DID) method to evaluate the impact of the target price policy (TPP) on rural household income in China. TPP had no significant impact on the total income of rural households. Specifically, TPP increased the farm income of rural households but simultaneously reduced the wage income and had no significant impact on the other income. Moreover, the impact of TPP on rural household income varied with the planting scale and income level; the effect of TPP was strong among the non-poor or scale operation rural households. TPP implementation affected rural household farm and wage income by affecting farmers' allocation of working time and cost input. Therefore, implementing TPP should consider farmers' participation in non-farm employment, further adjust the subsidy intensity and scope, and combine direct subsidies with the poverty reduction effect in poor areas. The contribution of this article is to explore the implementation effect of target price subsidy policies from the perspective of farmers' income, to deconstruct farmers' income, and explore the mechanism of policy action. This paper provides a theoretical basis and policy inspiration for China to improve and adjust the agricultural subsidy policy, mobilise farmers' enthusiasm to cultivate, and ensure national food security. [ABSTRACT FROM AUTHOR]

Geographical indication (GI) represents the specific good quality and reputation of the regional characteristics of agricultural products, which is a positive approach for stabilising the export of agricultural products, realising high quality and high prices for agricultural products and rural revitalisation. Based on the China-EU Geographical Indications Agreement, this paper discusses the differences between China and the European Union (EU) in terms of GI protection from three aspects: the institutional framework, the operational system, and the operational status of GIs. The purpose of the study is to identify the differences between China and the EU in the protection of GIs, China's shortcomings, and gaps, and to propose policy recommendations for China to protect GI products better, exploit the economic impact of GIs and enhance the competitiveness of China's exports. [ABSTRACT FROM AUTHOR]

This work discusses the differences in the removal efficiency of heavy metals in soils along the China-Russia crude oil pipeline in different vegetation backgrounds. In this paper, two representative forest types, birch forest and larch forest, were selected for replicated sampling and experimental study in the soil of disturbed and undisturbed areas along the pipeline, respectively. The results showed that after ten years of vegetation restoration, the amount of heavy metals in the soil of birch and larch forests decreased, the Cu content in the soil under the background of the birch forest was higher than that of the larch forest, while the Zn, Mn and Pb contents were lower than that of the larch forest. The order of decreasing magnitude was Mn, Pb, Zn and Cu, and the overall decreasing rate of heavy metal content in larch forest soil was more obvious. The above conclusions indicate that vegetation restoration is an effective measure to alleviate soil heavy metal pollution. [ABSTRACT FROM AUTHOR]

Rice cropped policy has been constantly changing, affecting the value of irrigated land. This study aims to examine distribution patterns of irrigated land value from a new perspective of uncertainties in single- and double-cropped rice policies in China. The real options approach was employed to calculate irrigated land value under policy uncertainty, and Moran's index was applied to identify the spatial distribution characteristics of irrigated land value at the provincial level. The empirical results were as follows: significantly positive spatial correlations existed between the land value under two cropped rice policies. The northeast region of China had a low-value clustering effect based on geographical characteristics. In contrast, the southern provinces of China had a high-value clustering effect based on the criteria of administrative regions. This study considered policy uncertainty when evaluating the economic effect on irrigated land when revealing spatial correlation in land value. We provide a theoretical and empirical basis for the formulation of cropped rice policies. [ABSTRACT FROM AUTHOR]

Enhancing the resilience of rural households against the impacts of risks and moulding their enduring strength despite modest scale holds paramount contemporary significance for a multitude of developing nations, including China. This study uses the microdata of the China Labor-Force Dynamics Survey (CLDS), systematically measures the rural household resilience index for the first time, analyses the impact of the digital economy on the resilience of rural households, and dissects the group differences and mechanism of action. We found that from 2012 to 2018, the Chinese rural household resilience index had significant differences in time and space, and village market, gentry assistance, economic organisation, and income from collective operation were the most important indicators affecting the rural household resilience index. The improvement of the digital economy index, to some extent, suppressed the improvement of the rural household resilience index. Meanwhile, heterogeneity analysis suggested that depending on family size and housing property rights, the impact of the digital economy on the resilience of rural households will be divided. Moreover, mechanism analysis showed that the digital economy further affected the resilience of rural households through the employment comprehensive effect, income structure effect and member security effect. [ABSTRACT FROM AUTHOR]

The paper utilizes the data envelopment analysis (DEA) method based on the OECD policy classification to evaluate the performance of the agricultural support policy at the provincial and agricultural commodity levels from the respective viewpoints of agricultural input and output. The analysis at the provincial level mainly focuses on the similarities and differences in the performance of the agricultural support policies between the primary grain-producing areas and the secondary grain-producing areas; at the agricultural commodity level, 17 representative Chinese agricultural commodities are selected and their performance compared. The results are then used to proffer suggestions for the future agricultural support policy optimization in China. The paper found that 50% of the provinces were DEA-efficient, in general, during the study period due to the low overall province-level scale efficiency. The performance values of the secondary grain-producing areas were significantly lower than those of the primary grain-producing areas due to the overall low scale and technical efficiency values. These results show that the support policies for agricultural commodities in China altogether require a further improvement, mainly due to the low technical efficiency of agricultural commodities. [ABSTRACT FROM AUTHOR]

Based on panel data from 2010 to 2020 of 151 A-share listed food-related enterprises in China, this research uses a fixed-effect model to analyse the impact of digital transformation on total factor productivity (TFP) in food--related enterprises. Our findings indicated that digital transformation has a positive and significant catalytic effect on TFP improvement in food-related enterprises. The mechanism test revealed that both cost-saving and innovation capacity enhancement effects of digital transformation contributed to the promotion of TFP improvement in these enterprises. Moreover, our heterogeneity analysis suggested that digital transformation is more effective in enhancing TFP in state-owned enterprises (SOEs) in the food-related industry, indicating that SOEs play a representative role in promoting advanced productivity in agricultural development. We also found that capital-intensive and technology- intensitve food-related enterprises were experiencing productivity paradox traps. Our results confirmed that digital transformation brings catch-up effects to labor-intensive food-related enterprises and those located in major grain production regions. Overall, this research can provide valuable insights for policymakers to upgrade the digital- -enabled food industry. [ABSTRACT FROM AUTHOR]

The widespread application of Internet technology in rural development has significantly facilitated the modernisation of agriculture and profoundly and positively impacts sustainable rural development. This study empirically investigates the effect of Internet access on farmers' participation in farmer professional cooperatives based on a sample of 3 349 participants from the 2020 China Rural Revitalization Survey (CRRS), using both probit regression and instrumental variable probit (Ivprobit) regression models. The results indicate that, firstly, Internet access significantly enhances farmers' participation in farmer professional cooperatives. Secondly, Internet access influences farmers' decisions to join professional cooperatives differently, with older farmers, those with less education, and non-cadre individuals being more significantly affected in their willingness to participate. The findings deepen the understanding of the relationship between digital technology and organisational participation in rural development and provide empirical evidence for formulating more targeted rural development policies. [ABSTRACT FROM AUTHOR]

Drunken horse grass (Achnatherum inebrians (Hance) Keng) is a toxic perennial bunchgrass native to Northwestern China. Epichloë endophytic fungi infection could enhance the stress tolerance of drunken horse grass. However, there is a scarcity of literature regarding the effects of intraspecific competition. As a result, we anticipated that the intraspecific competitive dynamics between endophyte-infected (EI) and endophyte-free (EF) plants would become more transparent for four years by planted as the proportions of 2: 1, 1: 1, and 1: 2. The results showed the EI plants exhibited more biomass, seed yields, and survival rates than EF plants. Endophyte infection also facilitated a competitive advantage by enhancing photosynthesis and soil nutrition. Our findings constituted the inaugural investigation into the influence of the intraspecific competitive ability of grass infected with Epichloë endophyte fungi. EI plants caused them to become stronger and stronger, while EF became weaker and weaker by timing and planting proportion increasing, and EF drunken horse grass could be replaced by EI. These conclusions were instrumental in elucidating why the endophytic fungal infection rate of drunken horse grass is 100% observed in natural wilderness. Epichloë endophyte could reduce plant diversity and enhance the dominance of EI plants in intraspecific competition; drunken horse grass may be threatening the persistence of native plant species. [ABSTRACT FROM AUTHOR]

Granted that the traditional measure methods in calculating trade openness always trigger results of singleness and twisted outcomes, the aim of the paper is to recalculate the Chinese produce trade openness after 1978, using new measure methods consisting of the trade reliance and shares. After calculation and contrasting, obvious differences have been found between the new and traditional methods. The results of the traditional measure methods turn out to be severely underestimated, whereas the new ones are more specific to reveal the extent of the Chinese produce trade openness, along with demonstrating the function of the Chinese produce in world trade market. Based on the results, utilizing the panel data, the LA/AIDS model and price elasticity, the paper analyses the changes that rural food prices were influenced by the agricultural produce trade openness, and the changes of rural food expenditure and consumption. [ABSTRACT FROM AUTHOR]

To reduce agricultural pollutant emission (APE) and postharvest loss of grain (PHLG), the Chinese government enacted a series of subsidy policies; however, the profit-oriented supply chain members are seriously lacking or reducing APE and PHLG efforts. To address this issue, we considered as the research objective a grain supply chain consisting of a producer, a retailer and the government. We proposed the concept and functional expressions of supply chain members' reduction efforts for APE and PHLG. We then proposed two main variables: the environmental innovation subsidy coefficient and the quantity attenuation factor of grain. According to the actual situation, four investment subsidy models were proposed. The results showed the following: i) supply chain members' equilibrium prices and incomes were negatively correlated with the degree of the producer's APE effort regardless of whether the supply chain members were investing in PHLG technology; ii) when the government subsidises APE and PHLG technology for other supply chain members, the government should stop subsidising the retailer's inputs in reduction loss technology to ensure that the government's own interests are not damaged; iii) the government's income was restricted by the degree of its subsidising of other supply chain members. This study provides a theoretical support for the government to formulate appropriate policies to reduce APE and PHLG, which is important for maintaining national food security. [ABSTRACT FROM AUTHOR]

Coloured rice has pigments deposited in the grain pericarp; red rice is the most common type of coloured rice. Red rice is rich in essential nutrients and has been grown and consumed in China for a long time. In this study, we report the genetic characterisation and preliminary molecular mapping of a mutant gene encoding red pericarp in rice (Oryza sativa L.). To analyse the genetic basis of the red pericarp mutant, a reciprocal cross between GER-3 (red pericarp, indica cv.) and 898 (white pericarp, indica cv.) was made. The genetic analysis results confirmed that there was only one dominant gene, temporarily designated Rp (Red pericarp) controlling the segregation of the red pericarp in the F2 population. For the molecular mapping of Rp, an F2 population derived from an inter-subspecific cross between Gene Engineering Rice-3 (GER-3) and C418 (japonica cv., white pericarp) was constructed. The genotype of the pericarp colour of the F2 individuals in the mapping population was validated by progeny testing of the F2:3 families. Simple sequence repeat (SSR) markers and the bulked segregation analysis (BSA) method were used; Rp was mapped to the short arm of chromosome 7 between the SSR markers RM21182 and RM21268, with a genetic distance of 3.5 and 12.0 cM, respectively. In this paper, the potential origin of the red pericarp mutant gene Rp was also discussed. [ABSTRACT FROM AUTHOR]

The Seriphidium transiliense desert pasture is an important spring-autumn pasture in northern Xinjiang, China, and has been subjected to grazing by livestock at different intensities, thus resulting in widespread deterioration of its biodiversity and ecosystem services. To understand the response mechanism of stoichiometric characteristics of desert vegetation to grazing, the leaf carbon (C), nitrogen (N), phosphorus (P) and C:N:P ratios of S. transiliense were studied under different grazing intensities. The results show that the control S. transiliense leaf C, N and P contents and C:N, C:P and N:P ratios were 458.79 ± 53.5 g/kg, 20.6 ± 7.18 g/kg, 2.83 ± 1.24 g/kg, 25.69 ± 11.08, 190.28 ± 75.65 and 8.21 ± 4.01, respectively. The differences in these characteristics varied with grazing intensity in accordance with sampling time, so both factors need to be considered comprehensively. General linear model (GLM) analysis indicated that grazing intensity had a strong main effect on S. transiliense leaf C, N, and P content, C:N ratio and N:P ratio. As grazing intensity increased, the leaf N content and N:P ratio increased (P < 0.01), and the C:N ratio decreased (P < 0.01). N content was the limiting factor for the growth of S. transiliense, but the grazing intensity, sampling year and growth season each affected the degree of N limitation. Our findings suggest that the remaining moderate stocking rate was essential for sustaining desert stabilisation in Xinjiang, and although S. transiliense could adapt its nutrient content and leaf stoichiometry to the grazing intensity, N was always the limiting element for the growth of S. transiliense. [ABSTRACT FROM AUTHOR]

Farms are key to agricultural advancement and carbon emission reduction. Understanding the influence of farm size on emissions is vital for eco-friendly farming. Our study used an econometric model with instrumental variable adjustments to examine the effect of farm size on greenhouse gas emissions, revealing an inverted U-shaped relationship. The findings revealed that emissions increased with farm size until a peak and then decreased. We identified an optimal farm size range (0.45 km² to 0.58 km²) for lower emissions, where the farm size maintaining the lowest greenhouse gas emissions per unit area was 0.58 km², while the lowest greenhouse gas (GHG) emissions per capita occured at a farm size of 0.69 km². Reducing emissions intensity per unit area is easier than reducing GHG emissions per person. Policymakers should prioritise promoting the expansion to moderately sized farms as a means of achieving emission reduction targets rather than solely increasing the number of farms. Overall, these insights offer policymakers novel approaches for ecological farm planning and the transition toward a low-carbon agriculture sector. [ABSTRACT FROM AUTHOR]

Fujian Province, China was chosen as the study area for estimating the marginal agricultural abatement costs within the province based on data for 2010-2020. The study employed these estimations as a pivotal factor affecting the efficiency of carbon emissions reduction, constructed an index model to gauge the potential of agricultural carbon emissions reduction, and delved into the urban agricultural carbon emissions reduction potential from the perspectives of economic development rights (equity) and carbon emissions reduction difficulty (efficiency). Our findings indicated a marked regional disparity in the marginal abatement costs of agriculture across Fujian Province, with the highest recorded at EUR 1.3771 × 108 per 104 tonnes and the lowest at EUR 0.6526 × 108 per 104 tonnes, albeit demonstrating general upward inter-annual trends. Furthermore, the assessment of agricultural carbon emissions reduction potential, grounded in the principles of equity and efficiency, revealed four distinct developmental tiers. Resource allocation pathways for carbon emissions reduction were subsequently delineated, informed by the stratification of high- and low-carbon emissions reduction potential indices alongside typological characteristics. The outcomes of this study offer strategic guidance to the government of Fujian Province in crafting suitable carbon emissions reduction strategies and in devising targeted action plans aimed at achieving the twin goals of 'carbon peaking' and 'carbon neutrality'. [ABSTRACT FROM AUTHOR]

Concerns for human health and food safety are gaining momentum in emerging and developing nations as well as in food research due to the reputations that products have established over time. Understanding cross-cultural consumers' purchasing behaviour for chicken meat (CM) could provide valuable insights into the global food sector since it is the most consumed meat worldwide. This study examines the effect of buying features (BF), culture factors, behavioural attitudes (BA), subjective norms (SN) and perceived behavioural control (BC) on CM actual purchase behaviour (APB) in China and Sierra Leone. Primary data were sourced from 588 Chinese and 410 Sierra Leonean participants. We adopt structural equation modelling (SEM) to verify the model and test the associations between the variables. The SEM results confirm that BF, BA, SN and BC stimulate customers' intent and actual purchase of CM in both nations. The findings indicate that cultural factors (CF) significantly moderates the association between the independent constructs (BF, BA, SN and BC) and APB in Sierra Leonean markets. This study provides significant insights for chicken industry stakeholders that can help them increase CM sales along the supply chain via a marketing strategy focused on cultural and psychological factors. [ABSTRACT FROM AUTHOR]

Asian sand dust (ASD), also called China dust or yellow dust, mainly occurs in East Asia during spring and autumn. Because ASD enters the body mainly through the respiratory system, it can cause respiratory disorders or worsen underlying diseases. Because of this, it has become an important health concern that threatens the well-being of humans and animals. In this study, we investigated the effects of 15 and 30 mg/kg of Pycnogenol (PYC15 and 30 groups), a pine bark extract, on ASD-induced pulmonary inflammation in mice. We evaluated the inflammatory cell counts, inflammatory cytokines, and matrix-metalloproteinase (MMP)-9 expression in animal models. PYC administration significantly decreased inflammatory cell infiltration into lung tissue; this was accompanied by a reduction in the levels of proinflammatory mediators including interleukin (IL)-1ß (P < 0.01), IL-6 (P < 0.01) and tumour necrosis factor-a (P < 0.01) in bronchoalveolar lavage fluids of ASD-exposed mice (ASD group). Histological analysis revealed that PYC suppressed ASD-induced pulmonary inflammation. Moreover, PYC suppressed the levels of matrix-metalloproteinase (MMP)-9 in the lung tissue of ASD-exposed mice, indicating that PYC reduced ASD-induced pulmonary inflammation by suppressing MMP-9. Together, these results indicate that PYC as the potential to treat ASD-driven pulmonary inflammation. [ABSTRACT FROM AUTHOR]

It is acknowledged that crude oil prices affect agricultural prices through both direct and indirect transmission schemes (i.e. exchange rate). In China, the matter of energy security may be immediately transmitted to the food security, imposing a pressure to China's macro-economy to a certain extent. Th is paper examines the long-run and short-run influence caused by the world crude oil prices and the RMB-dollar exchange rate on the five individual agricultural commodity prices (soybean, maize, wheat, colza oil, and japonica rice) in China. In this paper, the Granger causality approach is applied to test the long-run interrelationships with the weekly data from June 2002 to August 2013. In addition, the impulse-response analysis is utilized to study how the agricultural prices react to the sudden shocks in oil prices and exchange rate in the short term. The results reveal that the impulse response curves demonstrate that agricultural prices are not significantly affected by the abrupt changes in either oil prices or the exchange rate. Consistently, agricultural prices are neutral to the changes in oil prices in the long run while the exchange rate only Granger causes the prices of soybean. Ultimately, we present some sound reasons to explain the statistical results and propose some policy suggestions aimed at the China's food and energy security. [ABSTRACT FROM AUTHOR]

This paper selects four grain crops of rice, wheat, soybean, and corn, analyzes their foreign trade from 2002 to 2020, and estimates the virtual land resource. The research results show that China's grain has always been in the state of net import. China mainly exports rice and imports soybeans, and the market structure has an obvious trend of simplification. The net import of virtual land resources in China's grain has grown significantly and has outstanding contribution ability. The average annual net import is 62.25 million ha, which is almost equivalent to the arable land area of China's one-cropping area. The net import contribution of soybean virtual land resources is about 101 times of its sown area, while corn, rice, and wheat account for about 10.42, 11.69, and 74.66% of its sown area. The net importers of virtual land resources are relatively concentrated, mainly in Brazil, the US, Argentina, Ukraine, and Canada. [ABSTRACT FROM AUTHOR]

The paper examines the co-movements between the agricultural markets of China and the US. First, the empirical findings indicate that long-term equilibrium exists between the China and US soybean futures markets but not in the wheat futures markets. Second, there exists a significant spillover effect from the US to China in the wheat futures market, but the opposite effect is not strong; furthermore, for soybean futures, the spillover effect is bi-directional. Th ird, there is a unidirectional leading effect by the US agricultural futures markets on the Chinese market, particularly for agricultural products weakly controlled by the Chinese government. [ABSTRACT FROM AUTHOR]

Agricultural subsidy has attracted more and more attention. This paper captures the effects of subsidy (including area subsidy and price subsidy) on the total sown areas of crops based on the assumption that subsidy has both stimulating effects and inhibiting effects. Different from the prior studies, this paper considers the impacts of the farmland constraint and demand elasticity and some interesting conclusions are achieved. Firstly, a stimulating effect increases crop sown areas while an inhibiting effect reduces them. Secondly, the output efficiency of farmland as well as the demand elasticity has a major impact on the government subsidy. Besides, the capacity constraint makes thing difference and the government should choose between the areas subsidy and price subsidy under different conditions. Finally, this paper offers an empirical test on the conclusions by adopting the Chinese agricultural statistical data. [ABSTRACT FROM AUTHOR]

Emerging economies often establish commodity futures markets to discover price signals, manage price risks and improve market integration, but establishing a futures market may not be feasible for agricultural perishables. In this study, we evaluated the function of the world's first fresh fruit futures contract for apples. Combining partial cointegration with state-space modelling, we derived time-varying price discovery metrics for the apple futures market. Our findings revealed a limited and time-varying dominance of price discovery by the futures market, while a substantial share of price discovery occurred in the spot market. Moreover, poor convergence of disaggregated spot prices to the futures price suggests that commercial traders in the apple supply chain tended to focus more on the spot market than on the futures market. Thus, emerging economies should be cautious about the new establishment of futures markets for agricultural perishables. Future research using more specific data on the spot market may provide a better insight on the limited function of the futures market. [ABSTRACT FROM AUTHOR]

Land trusteeship involves farmers entrusting the farming and managing of their land to trustees, who manage the land on their behalf in exchange for a commission fee. Land trusteeship has been an important approach to bridging the gap between smallholder farmers and modern agriculture in China. Because of the information asymmetry in land trusteeship, farmers have higher uncertainty and perceived risk, so social trust and institutional constraints are particularly important in promoting farmers' participation in trusteeship. The objective of this study was to examine the impact of trust evolution and institutional constraints on smallholder farmers' decision-making in green prevention and pest control trusteeship. Our research was conducted in Shandong, China, utilising factor analysis and binary regression. The results revealed that trusteeship decision-making combines trust governance and institutional governance, with significant roles played by institutional trust, institutional supervision, institutional regulation, and interpersonal trust. As part-time farming became more prevalent, the importance of institutional trust and institutional supervision increased, indicating a shift in trusteeship governance from social relations to institutional contracts and the maturation of land trusteeship models. In addition, we also tested the interaction effect of social trust and institutional constraints and the heterogeneity effect of different trusteeship contracts. To improve the land trust system, we must enhance farmers' institutional trust and leverage the active role of intermediary supervision organisations such as village collectives. [ABSTRACT FROM AUTHOR]

How to encourage backers to increase investment and obtain more funds is an important issue for both initiators and platforms in reward-based crowdfunding. Based on the trust theory and the elaboration likelihood model (ELM), this study explores the impact of project information disclosure on the investment intensity of backers in agrifood crowdfunding. The results show that the initiator type, trademark registration, number of certificates, number of reward types, number of project updates, and number of comments had significant positive effects on backers’ investment intensity. Meanwhile, the investment threshold and lottery had a significantly negative impact on backers’ investment intensity. The number of backers played a mediating role in the relationship between independent variables and backers’ investment intensity. Based on the research conclusions, practical implications were proposed for initiators, crowdfunding platforms, and regulators. [ABSTRACT FROM AUTHOR]

Agricultural mechanisation is rapidly increasing in China and will have an increasing impact on agricultural total factor productivity (TFP) in the future. This study uses panel data from 27 provinces in China, spanning the years 2001‒2020, to measure agricultural TFP, and estimates the effects of mechanisation on TFP, technical efficiency, and technological progress. The results reveal that the level of agricultural mechanisation can promote TFP. TFP has a cumulative effect in the previous period, which can also significantly affect TFP in the current period. The level of agricultural mechanisation improves technical efficiency and promotes technological progress, but this is not statistically significant. Regional heterogeneity exists in mechanisation’s effect on agricultural TFP, with the largest effect occurring in the group with the lowest TFP. Therefore, efforts to promote the use of agricultural machinery should increase. China’s agricultural machinery subsidy policy must be further adjusted, and agricultural machinery research investments increased, while the government must address the heterogeneity between regions and focus on developing agricultural mechanisation in the central and western regions. [ABSTRACT FROM AUTHOR]

Phosphorus (P) deficiency significantly affects crop productivity, especially legume crops. Therefore, it is important to understand the P-acquisition strategies of different leguminous crops. In this study, we undertook a pot experiment with 11 legume crops (soybean, faba bean, pea, cowpea, common bean, lentil, adzuki bean, chickpea, grass pea, red kidney bean and common vetch) to investigate P-acquisition strategies related to root morphology, organic acid and acid phosphatase exudations, and arbuscular mycorrhizal fungi (AMF) colonisation under low (4.4 mg/kg) and optimal (40 mg/kg) P conditions. The results revealed that P deficiency significantly decreased biomass and P accumulation, root length (10.5%), and root surface area (7.9%), increased organic acid exudation (80.2%) and acid phosphatase activity (16.8%), and did not affect root diameter or root AMF colonisation rate. Principal component analysis revealed a positive correlation between organic acid exudation and acid phosphatase activity, while root length and root surface area negatively correlated with organic acid exudation, acid phosphatase activity and root AMF colonisation rate. P accumulation positively correlated with root length, surface area, and diameter but negatively correlated with organic acid exudation, acid phosphatase activity, and AMF colonisation rate. These findings confirmed the following: (1) legume crops use a P-mobilisation strategy related to organic acid exudation and acid phosphatase activity to acquire P under low soil P conditions; (2) organic acid exudation coincided with acid phosphatase activity to mobilise soil inorganic and organic P, improving P accumulation; (3) a trade-off exists between the P-scavenging strategy related to root morphology traits and mobilisation strategy. [ABSTRACT FROM AUTHOR]

Under the background of the Chinese Household Contract Responsibility System (HCRS), farmers have to pay higher transaction costs and encounter a huge trading risk if they engage in agricultural production only through the market transaction. Since the special properties of agricultural production limit the formation and development of agricultural enterprises, farmer cooperative economy organizations with the main functional characteristics of transaction coordination begin to flourish. By building a new classical economics model, this paper demonstrates the theoretical assertion that the generation of a farmer cooperative economy organization is accompanied by the evolution of the division of labour, the improvement of farmers' effectiveness and the development of agricultural specialization. Furthermore, this paper does an empirical analysis with the micro-survey data to verify this theoretical assertion. Therefore, this article effectively explains the generation condition of a farmer cooperative economy organization and the internal mechanism of how it promotes the development of agricultural specialization. So this paper provides a strong theoretical and practical evidence for the development of a farmer cooperative economy organization and agricultural specialization. [ABSTRACT FROM AUTHOR]

Our study comparative analyzed the morphological and physiological performance of Juglans regia L. cv. 'Xiangling' (JRX) grafted onto five rootstock species originated from China. A wide range of coefficient of variation (CV), 1.155--39.848%, was detected for fourteen indexes among the studied seedlings. CV of plant height, total dry biomass, total leaf area, root/shoot ratio, chlorophyll index, and stomatal conductance was higher than 15.00%, suggesting higher variation. Principal component analysis, hierarchical cluster analysis and subordinate function analysis were used to screen engrafted seedlings for their quality. All three methods produced the same result that seedling quality of 'Xiangling' engrafted with the five rootstock species from high to low were -- Juglans regia L. cv. 'Jizhaomian' (JRJ), JRX, Juglans regia L. cv. 'Lvxiang' (JRL), Juglans mandshurica, Maxim., and Juglans hopeiensis Hu.. The evaluation results were highly consistent with the actual growth performance of the engrafted seedlings, it verified the reliability of our results and the evaluation methods. The results demonstrated that JRJ, JRX, and JRL are potential rootstock candidates in the studied walnut planting regions. It would provide important implication for the selection of proper rootstock species for a certain particular walnut variety. [ABSTRACT FROM AUTHOR]

Soil rill erodibility (Kr) and critical shear stress (tc) are important parameters in some physical soil erosion models. In the present study, the temporal variations in Kr and tc by overland flow were investigated using undisturbed topsoil samples collected from three cropped plots (ryegrass, lucerne, and corn) and a fallow plot. In this study, the potential factors leading to these changes were examined from March to September 2022 in western Sichuan Province, China. The results revealed significant seasonal variations in Kr, tc, soil bulk density (SD), soil cohesion (SC), and soil water-stable aggregate (WSA). The Kr values were significantly lower, whereas tc values were slightly higher for cropped plots when compared to that for the fallow plot. The mean Kr values for cropped plots were 4.51~17.26 times lower than that for the fallow plot. In contrast, the mean tc values for the cropped plots were 1.03~1.08 times higher than that for the fallow plots. The results also indicated a negative correlation of Kr with SD, SC, WSA, soil organic matter content (SOC), and root weight density (RWD), while a positive correlation of tc with SD, SC, WSA, and RWD. Furthermore, an exponential decrease in Kr was observed with an increase in SD, SC, WSA, SOC, and RWD. An increase in SD, SC, WSA, and RWD of the experimental plots led to a further increase in tc. [ABSTRACT FROM AUTHOR]

Food security is a critically important issue in China and can be enhanced by implementing subsidy policies. This paper employs a partial equilibrium model which takes into account the impact mechanism of subsidy policies to simulate the impact of current subsidy policies on grain supply and demand and on enhancing grain self-sufficiency in China. The simulation results suggest that subsidies can generally promote grain production, reduce consumption, increase imports, reduce exports and increase ending stocks. Subsidies may also result in increases in grain self-sufficiency rate and stock-to-use ratio, but the increases are relatively small, indicating that the subsidies lack efficiency. Given that subsidies constitutes only a very small share of farmers' total income, and that significant scope remains for increasing subsidy levels in China, employing subsidy policies can help to enhance or at least maintain China's grain self-sufficiency at a high level. Various measures should be implemented to improve the inefficiency of the current subsidy system, such as (1) combining different types of subsidies; (2) providing discriminatory subsidies to poor/rich farmers or developing/developed areas; and (3) increasing subsidy rates for wheat and corn. [ABSTRACT FROM AUTHOR]

Soil erosion resistance is influenced by intrinsic soil properties and multiple external factors. This study investigated the effect of tea planting age on soil resistance to flowing water erosion (reflected by rill erodibility (Kr) and critical shear stress (tc)) in Three Gorges Reservoir Area. One slope farmland (as the control) and five tea plantations cultivated for 3 to 34 years were selected for sampling sites. The results indicated that bulk density (BD), soil cohesion (Coh), water stable aggregate (WSA), mean weight diameter (MWD), soil organic carbon (SOC), litter density (LD), and root mass density (RMD) increased generally with tea planting age. Compared to the control, Kr of tea plantations reduced by 71.1%-85.3%. The temporal variation in soil erosion resistance was controlled greatly by the variations in most near-surface characteristics. Kr decreased with WSA, Coh, LD, RMD, and SOC following a power function (P < 0.01); tc increased with MWD, LD, RMD, and SOC as an exponential function, with BD a power function, and Coh a logarithmic function (P < 0.01). In this study, Kr could be simulated well by WSA and LD with a power function, and tc could be simulated well by MWD and RMD with an exponential function. [ABSTRACT FROM AUTHOR]

The external fruit colour is an important parameter of the fig fruit quality. Fig anthocyanin content is critical for the peel colour. The peel of mature fruits of the fig cultivar Orphan and its red peel bud mutant Hongyan were separated for a transcriptomic and proteomic analysis. A total of 162 different abundance proteins (DAPs) and 5 015 differentially expressed genes (DEGs) were identified. The correlation analysis revealed that only two and 15 genes were downregulated and upregulated, respectively, at both the transcriptome and proteome levels. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis indicated that the enrichment pathways including Tropane, piperidine and pyridine alkaloid biosynthesis, phenylalanine metabolism and isoquinoline alkaloid biosynthesis for DEGs, and protein processing in the endoplasmic reticulum and flavonoid biosynthesis may contribute to the mutant color phenotype. Our results provide transcriptomic and proteomic information for two fig cultivars and may help to clarify the potential mechanisms of fig colouration. [ABSTRACT FROM AUTHOR]

Plague, a highly infectious disease caused by Yersinia pestis, has killed millions of people in history and is still active in the natural foci of the world nowadays. Understanding the spatiotemporal patterns of plague outbreaks in history is critically important, as it may help facilitate the prevention and control for potential future outbreaks. This study's objective was to estimate the effect of the topography, vegetation, climate, and other environmental factors on the Y. pestis ecological niche. A maximum entropy algorithm spatially modelled plague occurrence data from 2004--2018 and the environmental variables to evaluate the contribution of the variables to the distribution of Y. pestis. Our results found that the average minimum temperature in September (--8 °C to +5 °C) and the sheep population density (250 sheep per km2) were influential in characterising the niche. The rim of Qinghai Lake showed more favourable conditions for Y. pestis presence than other areas within the study area. Identifying various factors will assist any future modelling efforts. Our suitability map identifies hotspots and will help public health officials in resource allocation in their quest to abate future plague outbreaks. [ABSTRACT FROM AUTHOR]

Biochar is considered as a soil amendment for enhancing crop productivity. However, limited information is available on the residual effect of biochar application on rice grain yield and yield attributes. In this study, a fixed field experiment was conducted in a double rice-cropping system from 2017 to 2019. The dynamics of rice grain yield and yield attributes were monitored in the six growing seasons with 0, 20, and 40 t/ha biochar application. The re- sults showed that the averaged grain yields in the first four seasons were increased by 2.56-16.84% and 6.15-10.77% with 20 and 40 t/ha biochar application. The trend of increased grain yield in rice with biochar application during the first seasons was mainly attributable to an increase in total biomass, panicles per m2 and spikelets per panicle. Nonetheless, the grain yields in the sixth season were not influenced by biochar addition due to decreases in panicles per m2 and spikelets per panicle. Thus, it can be seen that the positive effects of biochar application on rice yield and yield attributes depend on the duration of biochar application. [ABSTRACT FROM AUTHOR]

The eastern foot of Helan Mountains in Ningxia belongs to the semiarid area and has been identified as the best wine grape producing area in China. In order to solve the problems of a high sugar content, organic acid falling too fast and severe shortage of acidity in the berries during ripening, which lead to lack of wine harmony, this study took Vitis. vinifera L. cv. 'Cabernet Sauvignon' as the experimental material and expanded nine treatments from setting to harvest. Nine rows were selected and divided into three groups, treated with mild (-0.20 MPa ≥ Ψb ≥ -0.40 MPa), moderate (-0.40 MPa ≥ Ψb ≥ --0.60 MPa), severe (Ψb ≥ -0.60 MPa) water stress from setting to veraison separately. From veraison to harvest, within each group, the mild, moderate, severe water stress were set, forming light-light (CK), light-medium (T1), light-heavy (T2), medium-light (T3), medium-medium (T4), medium-heavy (T5), heavy-light (T6), heavy-medium (T7), heavy-heavy (T8) treatments. The results showed that when the medium treatment was used from setting to veraison and the medium or severe treatment was used during post-veraison to harvest, it would facilitate the transportation and accumulation of sugar and improve the fruit quality. [ABSTRACT FROM AUTHOR]

Several experimental methods have been developed to fractionate soil organic carbon (SOC) into functional sub-pools. However, which fractions had the potential to better reflect the SOC dynamics responding to fertilisation are still under discussion. Thus, we compared different SOC fractions (microbial biomass carbon, MBC; dissolved organic carbon, DOC; permanganate-oxidisable carbon, POXC; particle organic carbon, POC, and aggregation organic carbon fractions) and the soil respiration rate in a wheat-corn rotation field after 40 years of manure and N fertilisation in North China to search for the most sensitive SOC fractions to fertilisation. Manure increased the organic carbon (OC) contents of all the soil fractions (26.5 to 362.8%) and the POC (18.0 to 43.7%) and macro-aggregation percentages (3.0 to 4.4%), which indicated an increasing physical-protected aggregated OC fraction. N fertilisation alone slightly increased the OC contents of all the soil fractions and DOC percentage, but decreased the macro-aggregation OC percentage, which suggests the increasing possibility that the SOC is exposed to microbial communities causing a decreasing aggregation formation. However, when a high level of both the manure and N fertiliser were applied, the excessive N in the soil stimulates the soil microbial activity and decreases the SOC content comparing it to the same level of the manure fertiliser addition. [ABSTRACT FROM AUTHOR]

Biochar-based fertiliser (BF) is beneficial to improve yield and quality, but the effect of BF on open field tomato remains unclear, especially in karst mountainous areas. The objective of this study was to identify the application effect and optimum application rate of BF. A field experiment was carried out in Southwestern China from 2019 to 2020 to study the effects of different application amounts of BF on the yield, quality, nutrients accumulation and fertiliser utilisation of open field tomatoes. The results showed that compared with the traditional fertilisation practice, BF can significantly increase the yield of open field tomato by 5-9% (2019) and 12-23% (2020), and significantly reduce nitrate content and increase vitamin C content of fruits. Meanwhile, nutrient accumulations, agronomic efficiency, and recovery efficiency of BF treatments were all significantly improved. In conclusion, the BF rate of 2 326 kg/ha improves yield and fertiliser utilisation in open-field tomatoes and could be recommended for tomato production in karst mountainous areas. [ABSTRACT FROM AUTHOR]

After entry into the WTO, China's domestic agricultural market is more and more closely integrated into the world market. Recently, a significant price fluctuation of agricultural commodities in the global market has increased concerns over its impact on the economic stability in those developing countries such as China, which has a large import and export of agricultural commodities every year. This paper attempts to study the short-term impact from price fluctuations of the world agricultural commodities upon the China's domestic agricultural market by investigating the dynamic correlation between the price change in the world and Chinese market in the copula framework. Our findings suggest a weak but strengthening short-run impact with an asymmetric nature. At the same time, diversified short-run impacts are observed in four main agricultural commodity markets. Empirical results show that the world price fluctuation has a volatile but decreasing influence on the China's rice market. This volatility of price impact is also observed in the wheat market but it has an escalating trend. The corn market experiences an intensified price shock with a distinct stage characteristic and the soybean market is under the strongest influence from the international price fluctuation. [ABSTRACT FROM AUTHOR]

As a new rebuilding agricultural soil on the North China plains, the salt-affected soil had a short soil-forming process of about 30 years. This paper describes the effect of different fertilization systems on phosphorus (P) dynamics in saline-alkali uncultivated land, in the reserved natural salt-vegetation back zone, and in different phases of fertilization for 24 years on the North China plains. The treatments included control (or check, CK), N1, N2, P1, P2, N1P1, N1P2, N2P1, N2P2. The contents of total phosphorus (TP) showed a significantly decreasing trend from 1.32-1.38 g P/kg to 0.40-0.96 g P/kg. The contents of rapidly available P (RP) were low in the no-P fertilizer treatments and the RP concentrations increased with P fertilizer applications. Corn was the crop that used the most P, especially in the no-P and P fertilizer-only treatments. The treatment with 270 kg N/ha/year and 59 kg P/ha/year represents the most economical fertilizer rates for these salt-affected soils on the North China plains. [ABSTRACT FROM AUTHOR]

Peatlands, as important global nitrogen (N) pools, are potential sources of nitrous oxide (N2O) emissions. We measured N2O flux dynamics in Hani peatland in a growing season with simulating warming and N addition for 12 years in the Changbai Mountains, Northeastern China, by using static chamber-gas chromatography. We hypothesised that warming and N addition would accelerate N2O emissions from the peatland. In a growing season, the peatland under natural conditions showed near-zero N2O fluxes and warming increased N2O emissions but N addition greatly increased N2O absorption compared with control. There was no interaction between warming and N addition on N2O fluxes. Pearson correlation analysis showed that water table depth was one of the main environmental factors affecting N2O fluxes and a positive relationship between them was observed. Our study suggests that the N2O source function in natural temperate peatlands maybe not be so significant as we expected before; warming can increase N2O emissions, but a high dose of N input may turn temperate peatlands to be strong sinks of N2O, and global change including warming and nitrogen deposition can alter N2O fluxes via its indirect effect on hydrology and vegetation in peatlands. [ABSTRACT FROM AUTHOR]

Since the reform and opening-up, the disparity between Chinese rural economy and the overall national economic development has already become the key constraint for further development of the national economy. In order to increase the farmers' income and to promote rural economic development, the efforts of China's budgetary and financial policies to support agriculture have been strengthened year by year. However, it lacks an accurate and effective assessment to evaluate the effects of China's fiscal and financial policies supports for agriculture. This paper proposes to estimate and measure the effects of China's fiscal and financial supports for agriculture utilizing the Chinese provincial panel data on the basis of the latest spatial panel econometric method. The results show that since China intensified the fiscal and financial support in 2004, the direct effects of fiscal and financial supports for agriculture have improved, but the spatial spillover effects have turned from positive to negative. [ABSTRACT FROM AUTHOR]

Farmer differentiation has important implications for the efficiency of farmland use. Applying the model of DEA and Tobit, using the household survey data, this paper investigates the effects of the farmer stratum differentiation on the efficiency of farmland use. The empirical results showed that the type of farmer differentiation was positive and statistically significant at 5% level. The regression coefficient is 0.295; this result implies that if this variable improves one percentage, the efficiency of farmland use will increase by 29.5%. The farmer horizontal differentiation and farmer vertical differentiation pass the significance test at the 1% and 5% level, respectively. This indicates that they all have a significant positive impact on the farmland use efficiency. We conclude that corresponding measures should be implemented to further facilitate the farmer differentiation. Another implication of our results is that the policies matched with the farmer differentiation and transfer should be gradually perfected, and then they will provide a better environment of the society and economy for free migration of farmers. [ABSTRACT FROM AUTHOR]

The purpose of this study is to empirically examine the impact of health on the off-farm income of China's migrant workers by the Heckman model. The dataset collected from the Research Center for Rural Economy, the Ministry of Agriculture of China between 2003 and 2007 was used in this paper. The results of both qualitative and quantitative analysis show that the health of flowing workers significantly influences their off-farm income. Flowing workers associated with a poor health condition earn less than those who are of good health, and the off-farm income gap due to the health condition widens year by year. In addition, poor health negatively impacts the off-farm participant decision for the China's rural residents. Therefore, more attention should be given to the health investment of migrant workers so as to improve their health and increase their off-farm income. [ABSTRACT FROM AUTHOR]

Farmland soil samples from the northern and southern banks of the Wangbeng section of the Huaihe River Basin, China, were collected and treated with three different low-molecular-weight organic acids (LMWOAs) (malic acid, citric acid, oxalic acid). This study aimed to determine how these acids affect soil phosphorus activation. The results showed that the average activation rate of total phosphorus, inorganic phosphorus, Fe/Al-P and Ca-P in soil samples from the southern bank treated with malic and citric acid was above 162%, except for organic phosphorus, with the highest at 192.04%. The three organic acids displayed significantly greater phosphorus activation in the northern bank soil samples than those of the southern bank. However, the overall average activation rate in the northern bank soils was lower than that of the southern bank. The four factors of phosphorus species, acid species, acid concentration, and treatment time had significant effects on phosphorus activation in the soils from both banks. This study showed that the three organic acids significantly activated inert phosphorus in the soil. Among them, malic acid and citric acid had a stronger effect on activating soil phosphorus and increased the available soil phosphorus utilisation rate. [ABSTRACT FROM AUTHOR]

In this study, 22 mung bean varieties from different producing areas in China were used as materials to provide a theoretical basis for the breeding and utilisation of special mung bean sprout varieties. Principal component analysis and cluster analysis were used to comprehensively evaluate the overall quality. Finally, 22 germinated mung bean varieties were divided into 3 edible quality grades according to their quality scores. The results showed that Lvfeng 2 and Ankang mung bean sprouts with better comprehensive characters were varieties with higher scores, which could be developed and utilised as characteristic mung bean sprouts. The content of protein, total phenol and antioxidant capacity of edible parts of Lvfeng 2 and Ankang mung bean after germination are higher than those of other varieties, so they are suitable for research and development as functional mung bean sprouts. [ABSTRACT FROM AUTHOR]

This study aims to test the overshooting effect of agricultural prices and the absorber hypothesis of exchange rates by extending the existing overshooting model. Using a combination of modern time series methods and monthly aggregate data from China, we demonstrate that overshooting of agricultural prices does indeed occur since the impact of monetary expansion on flexible agricultural prices is significantly larger than on relatively sticky industrial prices. Granger causality tests confirm that monetary expansion is a possible determinant of the movements of both agricultural and industrial prices, thus providing a solid empirical foundation for the overshooting hypothesis. Our findings also confirm the absorber hypothesis, in that the overshooting effect of agricultural prices under a fixed exchange rate regime (ERR) is shown to be greater than that under a floating ERR. The main policy implication is that policymakers should pay attention to the spillover effect of monetary expansion on agricultural prices when adjusting macroeconomic policies, especially under a fixed ERR. [ABSTRACT FROM AUTHOR]

Leaf rust caused by Puccinia triticina Eriks. (Pt) is one of the most devastating fungal pathogens affecting wheat (Triticum aestivum L.) production worldwide. Deployment of resistant cultivars is the most environmentally friendly approach to control the disease. In this study, thirty-seven wheat lines from the Hubei and Shaanxi provinces in China were evaluated for seedling resistance in the greenhouse using eighteen Pt races. These lines were also tested for slow rusting resistance in the field in the 2014 to 2018 growing seasons. Eleven molecular markers closely associated with known Lr genes were used as part of the postulation process. Seven known Lr genes, 1, 13, 18, 14a, 26, 34 and 46 either singly or in combination were postulated in twenty-five cultivars. Lr1 and Lr26 were the most commonly identified genes detected in thirteen and ten cultivars, respectively. Lr13 and Lr46 were each found in four and five cultivars. Lr34 was present in three cultivars. Lr18 and Lr14a were identified in cultivar Xi'nong 538. Six cultivars displayed slow rusting resistance in the field tests. The resistant cultivars identified in the present study can be used as resistance parents in crosses aimed at pyramiding and the deployment of leaf rust resistance genes in China. [ABSTRACT FROM AUTHOR]

To provide reference for scientific management of nitrogen (N) fertiliser on tartary buckwheat, the effects of the mixed application of controlled-release N fertiliser (a kind of thermoplastic polymer-coated urea types that are characterised by a semi-permeable membrane) and common urea was studied in the main tartary buckwheat production area in China. In 2018 and 2019, a two-year field experiment was conducted a randomised block design with five treatments: (1) no nitrogen fertilisation (CK); (2) 100% N from common urea (T1); (3) 15% N from controlled-released urea fertiliser (plastic coated) + 85% N from common urea (T2); (4) 30% N from controlled-released fertiliser + 70% N from urea (T3); (5) 45% N from controlled-released fertiliser + 55% N of urea (T4). The N fertilisation rate was 90 kg N/ha in all fertilisation treatments. The results showed: (1) the mixed application of controlled-release N fertiliser and common urea was conductive to enhance the yield, dry mass, N uptake and apparent N fertiliser efficiency (NFE), compared with a single application of common urea. In two seasons, NFE was 38.6% (T1), 48.6% (T2), 53.6% (T3) and 53% (T4), separately; (2) the mixed application of controlled-release N fertiliser and common urea could significantly increase the soil inorganic N content in the soil surface layer and decreased the leaching loss of N; (3) with the increasing ration of controlled-release N fertiliser, the tendency of increasing N content of crop uptake and soil residual and decreasing rate of N loss and N surplus was visible. Overall, considered the indicators of grain yield, input cost, N utilisation and N balance, the suitable N fertilisation mode for tartary buckwheat production is the mixed application of 30% controlled-release N fertiliser and 70% common urea when 90 kg N/ha is applied. [ABSTRACT FROM AUTHOR]

Soils that contain rock fragments (particles > 2 mm in diameter) are distributed all over the world. The presence of these small rock fragments can have a great impact on soil water retention properties, as well as on the soil-water infiltration and vegetation restoration in semi-arid regions. To quantitatively describe the transport of water in stony soils, repacked soil cores were used to determine the infiltration rates for different rock fragment contents (0%, 10%, 20%, 30%, and 40%) and rock fragment sizes (2-5, 5-8, 8-11, and 2-11 mm). The results showed that both the content and size of the rock fragments and their interaction significantly affected the infiltration process. The infiltration rates over time and the saturated hydraulic conductivity (Ks) decreased with an increasing rock fragment content to an observed minimum value for a 40% rock fragment content. The soil-water infiltration processes were accurately described by the Kostiakov model. The measured and calculated Ks values decreased with an increasing rock fragment content, which was in accordance with the published data and in accordance with the Ks obtained by five empirical methods. The variations in the measured Ks were likely due to the variations in the soil properties caused by the soil sample repacking. The results of this study may improve the understanding of the effects of the rock fragment content and size on the infiltration processes in arid and semi-arid desert steppes. [ABSTRACT FROM AUTHOR]

The present study used various amounts of P-arsanilic acid (AsA) in pot experiments to evaluate the effects of AsA on arsenic (As) accumulation, speciation and meanwhile using the in vitro digestion/Caco-2 cell model to evaluate the bioavailability of As in rice. The results indicated a linear relationship between As in rice and As in soil, and at 75 mg AsA/kg of soil, As content in rice exceeded the statutory permissible limit of 0.2 mg As/kg dry weight in China. Speciation studies indicated that inorganic As (Asi), dimethylarsinic acid (DMA), and monomethylarsonic acid (MMA) were the main As species in rice. Bioavailability of As experiment indicated that As uptake and transport amount by Caco-2 cells increased with increasing As accumulation in rice. In general, the content of AsA in soil reached or exceeded 75 mg/kg, which is not suitable for growing rice. [ABSTRACT FROM AUTHOR]