Analysis Of Climate Risk Rank On Maize Production In Ningxia

The impact of climate change on agriculture has been mainly adverse in recent years. There havebeen lots of climate change risk studies based on meteorological disasters and crop yield, but thequantitative assessment of climate change risk in the future is still insufficient. Considering droughtand waterlogging disasters and crop yield, taking maize in Ningxia province for example, this paperaims to identify and assess risk and its changes in the future so as to provide scientific evidence formaize production and policy decision in Ningxia.Three indicators of average yield reduction rate, lean year occurrence rate and coefficient ofvariance have been used to evaluate vulnerability of crop production based on the per unit area yieldof maize. At the same time, the data from observation stations were used into analyze drought andflooding happened during growth stages of maize. Based on the analysis, the climate change riskindex and risk zoning can be figured out. The same method is applied to assess risks in1961-1990(baseline) and2011-2040(2020s) based on grid data under A2and B2and the per unit area yield ofmaize. Its aim is to find out the difference of risk between baseline and actual situation, between twoscenarios of A2and B2and between baseline and two scenarios. The main conclusions are as follows:1. The result based on observation data and the per unit area yield of maize is consistent with thehistorical document, which proves the methods used in this paper is appropriate for Ningxia. Throughrejecting precipitation data which were less than or equal to0.5mm simulated from PRECIS model,the analysis of drought and waterlogging disasters and the actual situation are almost identical.2. The highest vulnerability of crop production in baseline appears in Ningxia southern mountainregion and the lowest vulnerability appears in Ningxia northern irrigation region. In contrast, thehighest one in2020s shows in Ningxia middle arid area and the lowest one still shows in Ningxianorthern irrigation region. The center of vulnerability of crop production in Ningxia moved fromsouthern mountain region to middle arid area.3. The worst meteorological droughts during baseline and2020s both happened in northernirrigation region during growth of maize. And the situation is better in southern mountain regionhappened in April and May. There were worse water loggings happened in southern mountain regionand middle arid area in August and September. The distribution of drought and waterlogging disastersindex is similar with it of flood. In condition, the number of grid happened drought and flood isincreasing under two scenarios. The worst drought will appear in northern irrigation region and themilder drought will show in southern mountain region. But the situation of flood shows the contrary.Drought and waterlogging disasters index is high in mountain areas and low in irrigation areas. What'smore, the drought will lighten in irrigation region and middle arid area and aggravate in mountainareas. The high value center will move from middle arid area in baseline to southern mountain regionin the future. 4. The conclusion of climate change risk of maize production in Ningxia shows that the risk ishigh in southern mountain region and middle arid area in the past and low in northern irrigationregion. The high risk in both baseline and2020s under two scenarios is in middle arid area and thelow one appears in northern irrigation region. Based on the criteria for risk distinction in baselineunder two scenarios, the risk scale under B2is larger than it under A2.5. The risk index in the future compared with which in baseline showed that, under the A2scenario the extent of risk would be mitigated and the value of risk index would be reduced on moregrids, while average level of risk would be decreased in three regions. Under the B2scenario, theextent of risk would be enhanced and the value of risk index would be increased on more grids, whilelevel of risks would be decreased in irrigation area, but increased in arid zones and mountainous areas.Which means that the climatic conditions in the2020s period under the B2scenario is not conduciveto the maize production in Ningxia, drought and waterlogging disasters, vulnerability and risk wouldbe increased. But the climatic condition under the A2emission scenario is in favor of maizeproduction. At average conditions, changes of the future warming would influence much more tomaize production in the central arid zone, while there would be no significant effects on the northernirrigation area.