A Sustainable Agro-ecological Solution to Water Shortage in the North China Plain (Huabei Plain)

Impact of different cropping systems and irrigation schedules on evapotranspiration, grain yield and groundwater level in the North China Plain

Incorporating the WHCNS model to assess water and nitrogen footprint of alternative cropping systems for grain production in the North China Plain

North China Plain (Huabei Plain) is one of the most densely populated regions on earth. Due to excessive underground water extraction, the North China Plain has been experiencing severe ground deformation over the last three decades. Therefore, for the purpose of hazard mitigation, it is necessary to monitor the ground displacement occurred in this region. As an extension of the differential radar interferometry (DInSAR) technique, advanced DInSAR techniques involving multiple images have demonstrated the potential to effectively map ground displacement. Such techniques are able to measure the temporal evolution of ground deformation with millimetre-level accuracy by using a stack of differential interferograms. In this study, the ALOS PALSAR data acquired over the North China Plain, which cover an area of approximately 16,000 km $$^2$$ , were processed based on the concept of advanced DInSAR techniques. Because of the large size of the PALSAR images, a targeted processing strategy was designed. This strategy is able to reduce required disk storage space and I/O operations, leading to the improvement of the computational efficiency. The resulting mean deformation velocity map demonstrates that a large portion of the area covered by the data was affected by various degrees of ground deformation between January 2007 and April 2010. The ground deformation is mostly distributed in rural areas, while the downtown areas are generally stable.

Recent Chinese Agriculture

The North China Plain (NCP) is the food bowl of the country. To feed the growing population, farmers in the area have been using the land very intensively with high inputs to increase food production. The sustainability of such farming practices has attracted the attention of scholars, planners and decision makers. This study analyses the economic and environmental sustainability of the major cropping systems in the NCP, based on selected site-specific indicators. The information necessary for this study was obtained in 2001 through a survey of 270 farm households from four villages in Ningjin county, soil sample analysis, chemical tests for nitrate concentration in groundwater and crop plants, field observations and discussions with key informants, as well as official reports and publications. The findings of the analysis revealed that all cropping systems in the study area were economically sustainable. However, such achievements have been made at a cost to the environment, degradation of natural resources and risk to human health. If these costs are taken into consideration, all cropping systems in the study area cannot be considered sustainable. The study stresses that farming practices that are economically sustainable should not be promoted at the cost of degrading production resources. There is a need for a policy shift from the promotion of agricultural production to sustainable agricultural production. Several policy measures have been outlined for the promotion of sustainable cropping systems in the NCP.

Future climate change impacts on grain yield and groundwater use under different cropping systems in the North China Plain

Improving nitrogen and water use efficiency in a wheat-maize rotation system in the North China Plain using optimized farming practices

Valuing the synergy in the water-energy-food nexus for cropping systems: a case in the North China Plain

Carbon emission of maize-based cropping systems in the North China Plain

Soil properties and crop yields after 11 years of no tillage farming in wheat–maize cropping system in North China Plain

The water-food-energy nexus evaluation and optimization of cropping system in the North China Plain: A case of county scale

Performance of different cropping systems across precipitation gradient in North China Plain

Low carbon footprint agriculture has received increasing attention in the effect of reducing greenhouse gas emissions and mitigating climate change. However, little is known about how crop diversification may affect the system productivity and the carbon footprint. In this study, we analyzed the carbon footprints of four cropping systems: winter wheat (Triticum aestivum L.)–summer maize (Zea mays L.) (WM, grain crop pattern, 1-year cycle); ryegrass (Lolium perenne L.)–sweet sorghum (Sorghum bicolor (L.) Moench) (RS, forage crop pattern, 1-year cycle); ryegrass–sweet sorghum → winter wheat–summer maize (RSWM, grain plus forage crop pattern, 2-year cycle); and switchgrass (Panicum virgatum L.) perennial cropping (SG, energy crop pattern) that have been evaluated in a long-term (2009–2015) field experiment in the North China Plain (NCP). Carbon footprints were expressed using three metrics: CFa (per unit area), CFb (per kg of biomass), and CFe (per unit of economic output). The results showed that switchgrass as a perennial herbaceous crop with one cut per year had the lowest annual carbon footprint at three metrics. The WM cropping system had the highest annual CFa, CFb, and CFe values which were 1.73, 2.23, and 1.78 times higher, respectively, than those of the RSWM cropping system. The RS cropping system had the lower annual CFa, CFb, and CFe values, which accounted for 20.9, 3.4, and 2.9%, respectively, of the WM cropping system. The four cropping systems had annual carbon footprints at per unit area, per kilogram of biomass and per unit of economic output ranked from lowest to highest of SG < RS < RSWM < WM. We conclude that appropriately designed, diversified cropping systems that include grain, forage, and bioenergy crops can effectively reduce the carbon footprint while maintaining or even increasing the systems productivity in the North China Plain.

Excessive nitrogen (N) and water input, which are threatening the sustainability of conventional agriculture in the North China Plain (NCP), can lead to serious leaching of nitrate-N (NO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;–&lt;/sup&gt;-N). This study evaluates grain yield, N and water consumption, NO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;–&lt;/sup&gt;-N accumulation and leaching in conventional and two optimized winter wheat-summer maize double-cropping systems and an organic alfalfa-winter wheat cropping system. The results showed that compared to the conventional cropping system, the optimized systems could reduce N, water consumption and NO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;–&lt;/sup&gt;-N leaching by 33, 35 and 67–74%, respectively, while producing nearly identical grain yields. In optimized systems, soil NO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;–&lt;/sup&gt;-N accumulation within the root zone was about 80 kg N/ha most of the time. In the organic system, N input, water consumption and NO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;–&lt;/sup&gt;-N leaching was reduced even more (by 71, 43 and 92%, respectively, compared to the conventional system). However, grain yield also declined by 46%. In the organic system, NO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;–&lt;/sup&gt;-N accumulation within the root zone was generally less than 30 kg N/ha. The optimized systems showed a considerable potential to reduce N and water consumption and NO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;–&lt;/sup&gt;-N leaching while maintaining high grain yields, and thus should be considered for sustainable agricultural development in the NCP.

Life in soil is a key driver of important ecosystem processes, such as the recycling of carbon and nutrients. In current intensive agricultural soils, however, richness and abundance of many groups of soil organisms are often reduced, which may threaten soil health and sustainable agriculture in the long run. Therefore, a switch to alternative agricultural practices (e.g., minimal tillage) that are less detrimental or even stimulate soil life has been suggested as a way to increase sustainable food production. Although we understand how some of these practices impact specific species or functional groups in soils, it is necessary to get a more complete overview to understand which practices can be used in agriculture to improve soil biodiversity. Here, we present a systematic literature review identifying which practices are studied as alternatives to current, intensive practices for four soil taxonomic groups encompassing a range of trophic groups and functions in the soil ecosystem: nematodes, earthworms, bacteria and fungi. Further, we review how these alternative practices impact the abundance and diversity of these four taxonomic groups, as well as for the 14 functional groups identified and retrieved from the review. We found that a total of 23 alternative agricultural practices, grouped into 10 groups of practices, were studied for the four target taxonomic groups. Three groups of practices, 'fertilization’, ‘soil cover’ and ‘tillage’ were studied for all taxa. In general, alternative agricultural practices had positive impacts on the species richness in the four taxonomic groups and on the abundance of organisms in the functional groups. However, there were some exceptions. For example, organic fertilizers reduced the abundance of epigeic earthworms, while enhancing the abundance of endogeic and anecic earthworms. There was only one alternative practice, i.e., the use of cover crops, that was neutral to positive for the abundance of all functional groups across all taxa. Our review revealed that there are gaps in the literature, as practices that are commonly studied for aboveground biodiversity, such as field margins or flower strips, are not studied well across taxonomic and functional groups and need to be further studied to improve our understanding of the impact of alternative practices on soil life. We conclude that alternative agricultural practices are promising to enhance soil biodiversity. However, as some practices have specific impacts on taxonomic groups in the soil, we may require careful application and combinations of alternative agricultural practices to stimulate multiple groups.