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China’s agricultural production suffers significant constraints due to low water productivity (WP) and partial factor productivity for nitrogen (PFPN). The pivotal solution to enhance maize yield, WP, and PFPN is through optimizing field management practices. However, previous studies primarily focused on the effects of individual or coupled field management practices on maize yield, WP, or PFPN in an area or land mass, so it is necessary to conduct a comprehensive quantitative analysis of various field management practices on maize yield, WP, and PFPN at the national scale. In this study, we compiled 286 studies encompassing 6959 pairs of experimental data spanning from 1990 to 2023. Meta-analysis was conducted to observe the variations in maize yield, WP, and PFPN across diverse field management practices (straw returning, nitrogen fertilizer application, irrigation practice, and tillage practice) on a national scale. The results showed that nitrogen fertilizer application (215 kg N ha−1) was the most effective in enhancing maize yield and WP by 68.1 % and 54.8 %, respectively. Additionally, irrigation had the most substantial impact on PFPN, enhancing 16.8 %. Straw mulching, application of slow and controlled release fertilizers, drip irrigation, and subsoiling were identified as the most effective practices in increasing maize yield, WP, and PFPN by Random forest model. Maize straw returning could reduce nitrogen fertilizer application by 20 kg ha−1, while increasing WP and PFPN by 4.2 % and 11.6 %, respectively. Moreover, straw returning could reduce water consumption by 23–60 mm, while increasing WP and PFPN by 2.9 % and 6.8 %, respectively. These findings can provide a reference for the formulation of comprehensive management strategies for sustainable maize production in China and globally.

Acetylcholinesterase (AChE) is an essential neurotransmitter hydrolase in nervous systems of animals and its number varies among species. So far, five AChEs have been identified in the natural enemy Pardosa pseudoannulata. Here we found that Ppace1, Ppace2 and Ppace5 were highly expressed in the spider brain, among which the mRNA level of Ppace5, but not Ppace1 and Ppace2, could be up-regulated by organophosphorus insecticides at their sublethal concentrations. In spider brain, the treatment by organophosphorus insecticides at the sublethal concentrations could increase total AChE activity, although high concentrations inhibited the activity. The activity that increased from the sublethal concentration pretreatment could compensate for the activity inhibition due to subsequent application of organophosphorus insecticides at lethal concentrations, and consequently reduce the mortality of spiders. PpAChE1 and PpAChE2 were highly sensitive to organophosphorus insecticides, and their activities would be strongly inhibited by the insecticides. In contrast, PpAChE5 displayed relative insensitivity towards organophosphorus insecticides, but with the highest catalytic efficiency for ACh. That meant the up-regulation of Ppace5 under insecticide exposure was important for maintaining AChE activity in spider brain, when PpAChE1 and PpAChE2 were inhibited by organophosphorus insecticides. The study demonstrated that multiple AChEs in the spider brain worked collaboratively, with part members for maintaining AChE activity and other members responding to organophosphorus inhibition, to provide protection from organophosphorus insecticides. In fields, high concentration insecticides are often applied when ineffective controls of insect pests occur due to relative-low concentration of insecticides in last round application. This application pattern of organophosphorus insecticides provides more chances for P. pseudoannulata to survive and controlling insect pests as a natural enemy.

Ammonia volatilization (NH3) and nitrous oxide (N2O) emission are the main underliers of nitrogen loss in farmlands, which can decrease nitrogen use efficiency and trigger environmental problems regarding greenhouse effects. Previous studies have regional limitations and lack universal guiding significance, as they are primarily based on individual experiments related to the effects of applying nitrogen fertilizer on maize. In this study, we performed a meta-analysis on a regional scale to investigate the overall impact of nitrogen fertilizer application on maize yield, N2O, and NH3 in Northeast China. The database included 85 studies and 1147 pairs of experimental data that were analyzed. The results showed that applying nitrogen fertilizer significantly increased maize yield, N2O emissions, and NH3 volatilization effects, and the growth rates (E) were 50.64%, 64.39%, and 69.25%, respectively. In Northeast China, the average emission factors of N2O and NH3 were 0.72% and 8.21%, respectively. The optimum nitrogen application rate for maize in Northeast China was 205 kg ha−1, resulting in 8.37% nitrogen loss (through N2O and NH3). Soil texture, alkaline nitrogen (AN) content in the soil, mean annual precipitation (MAP), nitrogen application rate, and fertilizer type were the key influential factors affecting changes in maize yield and N loss (N2O and NH3). Yield-scaled N2O and NH3 were found to be the significant emission reduction parameters that ensured maize yield. However, there was a remarkable ‘seesaw effect’ between yield-scaled N2O and NH3 under the same natural conditions (MAP and soil texture). Therefore, human activities such as reducing N surplus in soil, and N fertilizer application rate, along with selecting suitable fertilizer types should be given more attention to reduce yield-scaled N2O and NH3. Moreover, minimizing NH3 and N2O dual emission should be the main objective for green agriculture in Northeast China, rather than over-emphasizing on single emission reduction.

There have been a variety of deadlock control strategies proposed for automated manufacturing systems (AMSs) without taking unreliable resources into account in the framework of Petri nets. However, in addition to deadlocks, resource malfunction problems may also arise to make a system collapse in the real world. This paper develops a new deadlock control method for a generalized system of simple sequential processes with resources (GS3PR), where a class of unreliable GS3PR (U-GS3PR) is considered. Recovery subnets are used to describe an unreliable resource failure and its recovery process in a Petri net model. First, we compute all the strict minimal siphons (SMSs) in a GS3PR net. Second, with the concept of max-controllability of siphons, a monitor is added to each SMS. However, the net loses liveness when unreliable resources are taken into consideration with recovery nets being added for their operation places. Then, by using the concept of constraint set, we add related arcs between the transitions in recovery subnets and original monitors. Finally, a robust deadlock controller is designed for the AMSs according to the max-controllability of siphons.