Plant Adaptation to Flooding Stress under Changing Climate Conditions: Ongoing Breakthroughs and Future Challenges.

Climate-change-induced variations in temperature and rainfall patterns are a serious threat across the globe. Flooding is the foremost challenge to agricultural productivity, and it is believed to become more intense under a changing climate. Flooding is a serious form of stress that significantly reduces crop yields, and future climatic anomalies are predicted to make the problem even worse in many areas of the world. To cope with the prevailing flooding stress, plants have developed different morphological and anatomical adaptations in their roots, aerenchyma cells, and leaves. Therefore, researchers are paying more attention to identifying developed and adopted molecular-based plant mechanisms with the objective of obtaining flooding-resistant cultivars. In this review, we discuss the various physiological, anatomical, and morphological adaptations (aerenchyma cells, ROL barriers (redial O2 loss), and adventitious roots) and the phytohormonal regulation in plants under flooding stress. This review comprises ongoing innovations and strategies to mitigate flooding stress, and it also provides new insights into how this knowledge can be used to improve productivity in the scenario of a rapidly changing climate and increasing flood intensity.

Impact of the second phase of the eastern route of South-to-North water diversion project on distribution of nitrogen and phosphorus in Hongze Lake.

Nitrogen (N) and phosphorus (P) concentrations are the fundamental factors affecting the nutrient status and productivity of lakes, and extrinsic inputs of N and P primarily cause eutrophication of lakes. In this essay, taking Hongze Lake as the study area, a two-dimensional hydrodynamic and water quality mathematical model of Hongze Lake was constructed, and based on calibration and verification of parameters, numerical simulation was performed on the changes in N and P concentrations in this lake after water transfer. The study results exhibited that before and after project construction, the absolute values of rates of changes in the annual average concentrations of ammonia nitrogen (NH4+-N), total phosphorus (TP), total nitrogen (TN), and permanganate index (CODMn) in Hongze Lake were all lower than 20%, which demonstrates marginal changes in the annual average concentrations. By analyzing the seasonal and spatial distribution characteristics of the concentrations of N, P and other pollutants in the lake area before and after the project operation, it is found that the main reasons that affect the water quality change in the lake area after the project operation are the newly added water transfer volume, water transfer location, and water transfer quality.