Wei Qin

Global crop yields are limited by water and nutrient availability. Soil mulching (with plastic or straw) reduces evaporation, modifies soil temperature and thereby affects crop yields. Reported effects of mulching are sometimes contradictory, likely due to differences in climatic conditions, soil characteristics, crop species, and also water and ni...

A quantitative understanding of yield response to water and nutrients is key to improving the productivity and sustainability of rainfed cropping systems. Here, we quantified the effects of rainfall, fertilization (NPK) and soil organic amendments (with straw and manure) on yields of a rainfed wheat-soybean system in the North China Plain (NCP), us...

Increasing crop yield and water use efficiency (WUE) in dryland farming requires a quantitative understanding of relationships between crop yield and the water balance over many years. Here, we report on a long-term dryland monitoring site at the Loess Plateau, Shanxi, China, where winter wheat was grown for 30 consecutive years and soil water cont...

Deep fertilization (DF) has been introduced to rice production systems in China to improve rice productivity with minimum nitrogen (N) losses, however, the effects of DF on rice yield and ammonia (NH3) emissions were never analyzed systematically. In the present study, we evaluated the impact of DF on rice productivity and NH3 emissions via a meta-...

Purpose Substituting chemical fertilizers with organic manure may alleviate soil acidification in vegetable fields, but the optimum organic manure substitution ratio (SR, the ratio of organic nitrogen (N) rate to total N application rate) may vary due to different climatic conditions (mean annual precipitation (MAP), mean air temperature, and clima...

China is a major producer of wheat, maize and rice, which generates massive greenhouse gas emissions due to the consumption of elevated amounts of energy, land, and water, yet there is actually few knowledge on the spatial heterogeneity of greenhouse gas emissions. Here, we introduce a polyphasic approach to quantify the emissions from the land, en...

Whether or not chlorophyll a (Chla) is limited by nitrogen (N) or phosphorus (P), or both, remains highly debated, in part this is due to the lack of a robust statistical rarely considered using a statistical method in studies of peer-review research of lakes. Individual studies only used the use of the relationship between Chla and nutrients to ju...

Agricultural cereal production plays a crucial role feeding the world’s growing population, particularly pertaining to rice, wheat, and maize. Cereal production requires vast amounts of land and enormous energy and water resources, potentially leading to greenhouse gas (GHG) emissions. However, very little information exists on GHG emissions result...

Subsoil compaction is an increasing problem in modern agriculture, but is not easily recognized in practice, also because of possible within-field spatial variations. This paper addresses the question of how within-field spatial variations in soil bulk density and other soil characteristics relate to within-field spatial variations in crop yield an...

International trade of agricultural products has greatly increased over time, but its impacts on sustainable development are debated. It may contribute to food security in importing countries, increases the dependency between countries, and has been implicated in displacement of environmental pollution and resource depletion. There is also discussi...

Background: The compaction of subsoils in agriculture is a threat to soil functioning. Measures aimed at the prevention, amelioration, and/or impact alleviation of compacted subsoils have been studied for more than a century, but less in smallholder agriculture. Methods: A meta-analysis was conducted to quantitatively examine the effects of the pre...

Potassium (K) is a critical plant nutrient that determines quality in a myriad of crops and increases production yields. However, excessive application of various types of K fertilizers can decrease both the food quality and yields, which translates as economic losses and food safety issues. The objectives of this study were to 1) elucidate the imp...

Summer catch crop planting is commonly adapted to increase soil biodiversity and effectively reduce N leaching in intensively managed vegetable fields with double‐cropping systems (winter‐spring season and autumn‐winter season) in China. However, little has been reported on the combined effects of summer catch crops (i.e., sweet corn [Zea mays L.])...

Microsensors are able to accurately quantify nitrous oxide (N2O) emissions in microenvironments at high spatio-temporal resolution; yet, limited studies have been conducted on agricultural soils due to the inability to obtain electrical signal under conditions of low soil moisture. This study improved the calibration of a microelectrode for measuri...

Crop production is often affected by multiple agronomic factors. However, little has been reported on the synergistic effects of multiple factors on crop production. Here, we reported the effects of five factors (i.e., variety, planting density, nitrogen application, supplemental irrigation, and plastic mulching) on crop yields, using data from a 5...

The accurate and nondestructive assessment of leaf nitrogen (N) is very important for N management in winter wheat fields. Mobile phones are now being used as an additional N diagnostic tool. To overcome the drawbacks of traditional digital camera diagnostic methods, a histogram-based method was proposed and compared with the traditional methods. H...

Meta-analysis is a statistical analysis of the data obtained from multiple studies and provides a quantitative synthesis of research results. It can be a key tool for facilitating rapid progress in aquaculture by quantifying what is known and identifying what is not yet known. However, due to the complexity of the environment and problems associate...

The performance of fertilizers may differ significantly in different soils. Here, we quantify effects of various phosphorus (P) fertilizers on maize yield and P uptake in soils with different pH values, using a pot experiment. Five P fertilizers were used; monoammonium phosphate (MAP), diammonium phosphate (DAP), calcium superphosphate (CSP), calci...

Liquid biofuels from non-grain energy crops on marginal land could become an important substitute of gasoline in the transport sector, and offer the possibility to reduce competition with food crops for land resources. However, the cultivation of energy crops is facing profound challenges due to changing temperature and precipitation in the future....

A quantitative understanding of nitrogen (N) fate is a key for designing an optimal integrated N management for a sustainable high yielding maize system. In this study, we explored optimal N application rates and split using the data of a 2-year field experiment (2014-2015) with labeled 15 N. The results showed that, plastic film mulch significantl...

Recent development of non-destructive optical techniques, such as spectroscopy and machine vision technologies, have laid a good foundation for real-time monitoring and precise management of crop N status. However, their advantages and disadvantages have not been systematically summarized and evaluated. Here, we reviewed the state-of-the-art of non...

Effective policy measures are required to control environmental problems caused by nitrogen (N) fertilizer use in intensive crop production systems in China. However, simply reducing the use of N fertilizer in allregions may be detrimental to food security. Here we reviewed N management policies and indicators,with a particular focus on European Un...

Plants require 14 nutrient elements in specific amounts for growth and development, in addition to carbon dioxide, water, and photosynthetic active radiation. The most limiting nutrient elements are nitrogen, phosphorus, and potassium. This chapter briefly summarizes the driving forces of nutrient cycling and the changes in global nutrient flows an...

Millions of small farmers rely on maize (Zea mays L.) produced in the Loess Plateau of China. The purpose of this study was to find a fine maize variety in the Check Dam and to reveal the reasons for the effects of white plastic film mulch and maize varieties on crop yield and photosynthetic characteristics. Three maize cultivars (Dafeng 26 [DF], X...

China has an extreme shortage of potassium (K) resources, despite the overuse of fertilizers that has been commonly reported in Chinese intensive cropping systems and has resulted in nutrient imbalance and adverse effects on the environment. Application of fertilizers with manure may increase nutrient recycling and use efficiency, but little is kno...

China has been seriously affected by particulate matter (PM) and gaseous pollutants in the atmosphere. In this study, we systematically analyse the spatio-temporal patterns of PM2.5, PM10, SO2, CO, NO2, and O3 and the associated health risks, using data collected from 1498 national air quality monitoring sites. An analysis of the averaged data from...

Composting is an important technology to treat biowastes and recycle nutrients, but incurs nitrogen (N) losses that lower the value of the final products and cause pollution. Technologies aimed at reducing N losses during composting have inconsistent outcomes. To deepen insight into mitigation options, we conducted a global meta-analysis based on 9...

Composting of solid waste can be associated with a loss of the agronomic value (nutrient loss), as well as a source of environmental impact through the emission of the greenhouse gases (GHG) nitrous oxide (N2O) and methane (CH4) and volatilization of ammonia (NH3). Additives have been considered as a useful option to mitigate these environmental em...

Solar greenhouse vegetable fields have been found to be hotspots of nitrous oxide (N2O) emissions in China, mainly due to excessive manure application and irrigation. Pulses of N2O emissions have been commonly reported by field monitoring works conducted in greenhouse fields, though their significance regarding total N2O emissions and the driving m...

The glacial retreat is observed and predicted to increase in intensity especially in high-elevation areas as a result of global warming, which leaves behind a primary succession along soil chronosequences. Although soil microbes have been recognized as main drivers of ecological and evolutionary processes, our understanding of their effects on nutr...

Agricultural nitrogen (N) and phosphorus (P) emissions to water bodies remain largely unknown in China, mainly due to the lack of reliable data sources and quantification tools. In this study, we constructed a grid-based NUFER (NUtrient Flow in food chains, Environment and Resources use) model in order to quantify a high-res- olution agricultural N...

Conventional flooding paddy systems consume large amounts of water and results in water body pollution due to low water (WUE) and nitrogen use efficiencies (NUE). Therefore, rice production systems with water-saving and high resource use efficiencies need to be developed. A two-year field experiment was conducted in Fangxian County of Hubei Provinc...

Over-exploitation of groundwater for irrigation has led to a series of ecological and environmental problems in the North China Plain (NCP). Identifying the water consumption and groundwater level dynamics under different cropping systems can help to develop groundwater neutral system in the NCP. The WHCNS (soil Water, Heat, Carbon and Nitrogen Sim...

Manure management is an important aspect of urban livestock production that has a profound impact on metropolitan living. Data were collected from 28 dairy farms in peri-urban Beijing and analysed to determine farm nitrogen and phosphorus flows and costs associated with various manure management options to reduce nutrient losses. Dairy production i...

Chinese intensive greenhouse vegetable systems are characterized by high input of water and nutrients, which are not sustainable. There is an urgent need to explore smart and practical strategies to convert the “high input-low output” systems to “optimal input-output” ones. This study aimed to evaluate the effects of different catch crops on reduci...

The amount of organic residues and waste in China and their uncertainties have not been quantitatively analysed, due to the lack of reliable data and proper quantification tools. Here we quantified the changes of crop residue and livestock manure in Chinese agriculture from 1978 to 2014, using coefficients collected from literature and a large stat...

Nitrogen (N) leaching is a commonly reported problem in protected vegetable production in China due to poor management. To minimize soil residue N and reduce N leaching, sweet corn is often used as the summer catch crop after the winter-spring growing season. However, the effectiveness of this practice has never been systematically quantified befor...

International trade of food and feed has facilitated the specialization and agglomeration of agricultural production systems in many countries. Confined animals in specialized production systems are increasingly supplied with soybean and maize, imported from other countries. This has increased animal productivity but has also contributed to spatial...

Livestock production in peri-urban areas constitutes an important sub-sector of the agricultural production system in China, and contributes to environmental degradation and local air borne pollution contributing to smog. As a result, local policies are being implemented to safeguard the environment. However, there has been little attempt to quanti...

Excessive water and fertilizer inputs have led to a series of environmental problems in vegetable production areas in China. Identifying the fates of water and nutrients is crucial to develop best management strategies in intensive vegetable production systems. The objectives of this study were to (i) develop a scientific water and nitrogen (N) man...

Water and nutrient availability significantly limits global crop production, especially for dryland agriculture in arid and semi-arid regions. To explore the optimal soil mulching options for the Loess Plateau in China, a 3-year field study was conducted to investigate the effects of various soil mulching practices on soil temperature and the water...

Simulation models based on cellular automata (CA) are widely used for understanding and simulating complex urban expansion process. Among these models, logistic CA (LCA) is commonly adopted. However, the performance of LCA models is often limited because the fixed coefficients obtained from binary logistic regression do not reflect the spatiotempor...

China has become the largest mineral phosphorus (P) fertilizer consumer in the world, but current use is not sustainable. Here, we report on a quantitative analysis of the P use and losses in the food production–consumption chain and of their relationships with socio-economic indicators for the years 1950–2010. Pathways to a more sustainable P use...

Intensive livestock production expands rapidly around cities to meet the food demand and the improvement of people's living standard in developing countries, such as China. However, little is known about the environmental costs and socio-economic performances of these systems. Here, the performance of peri-urban pig farms in Beijing was assessed, u...

China's livestock and poultry productions have changed significantly in the last three decades, from mainly traditional and small-scale systems in early 1980s towards more intensive and industrialized ones in recent years, due to the booming economy and the changes in people' diet. There is an urgent need to increase the understanding of the change...

Global crop production is significantly limited by water and nitrogen (N) input. However, these two limiting factors were often studied separately. There is limited information about water and N interactions and the simultaneous optimization strategies in crop systems, as function of climate, soils, crops and field management. Hence, I explore opti...

China has successfully achieved food self-sufficiency over the past 50 years, however, with large inputs and losses. To meet the challenge of feeding a growing population with limited resources, many studies have explored options for improving productivity and efficiency of the food production. However, there have been few studies into the potentia...

China's pig production has increased manifold in the past 50 years, and this has greatly affected the nitrogen (N) and phosphorus (P) use and losses in the pig production sector. However, the magnitude of these changes are not well-known. Here, we provide an in-depth account of the changes in pig production, and N and P use, and total N and P losse...

The usual perception of consumers regarding water consumption is that their bills do not match their actual water consumption. However, this mismatch has been insufficiently studied; particularly for cases related to specific water-use patterns, water conservation practices, and user socio-demographics. In this study, a total of 776 households in 1...

Background and aims Sufficient soil phosphorus (P) is important for achieving optimal crop production, but excessive soil P levels may create a risk of P losses and associated eutrophication of surface waters. The aim of this study was to determine critical soil P levels for achieving optimal crop yields and minimal P losses in common soil types an...

Background and aims Sufficient soil phosphorus (P) is important for achieving optimal crop production, but excessive soil P levels may create a risk of P losses and associated eutrophication of surface waters. The aim of this study was to determine critical soil P levels for achieving optimal crop yields and minimal P losses in common soil types an...

The Nitrogen (N) and phosphorus (P) costs of food production have increased greatly in China during the last 30 years, leading to eutrophication of surface waters, nitrate leaching to ground water, and greenhouse gas emissions. Here, we present the results of scenario analyses in which possible changes in food production - consumption in China for...

Crop and animal production in China has increased significantly during the last decades, but at the cost of large increases in nitrogen (N) and phosphorus (P) losses, which contribute to ecosystem degradation and human health effects. This information is largely based on scattered field experiments, surveys and national statistics. As a consequence...

Urbanization and agriculture are highly coupled. However, the impacts of urbanization(e.g. transformation in urban and rural population and change in diet) on water and nitrogen (N) use remain poorly understood. The objectives of this study are to quantify water flows in the food chain of China, to analyze the complex relationship between urbanizat...

Increasing nitrogen (N) and phosphorus (P) inputs have greatly contributed to the increasing food production in China during the last decades, but have also increased N and P losses to the environment. The pathways and magnitude of these losses are not well quantified. Here, we report on N and P use efficiencies and losses at a national scale in 20...

Urbanization develops rapidly especially in the developing countries. As a consequence, an increasing amount of food, especially animal-derived food, has to be produced on a decreasing area of agricultural land. However, the impacts of these changes on water and nitrogen use efficiencies remain poorly understood. Here, we analyze the complex relati...