Synergistic effects of climatic factors and drought on maize yield in the east of Northwest China against the background of climate change

Based on the hydrological and meteorological data of the upper reaches of Shiyang River basin in Northwest China from 1960 to 2009, this paper analyzed the change in runoff and its related climatic factors, and estimated the contribution of climate change and human activity to runoff change by using the moving T test, cumulative analysis of anomalies and multiple regression analysis. The results showed that temperature revealed a significant increasing trend, and potential evaporation capacity decreased significantly, while precipitation increased insignificantly in the past recent 50 years. Although there were three mutations in 1975, 1990 and 2002 respectively, runoff presented a slight decreasing trend in the whole period. The contributions of climate change and human activity to runoff change during the period of 1976-2009 were 45% and 55% respectively.

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Predicting Lake Quality for the Next Generation: Impacts of Catchment Management and Climatic Factors in a Probabilistic Model Framework

Water ◽

10.3390/w11091767 ◽

2019 ◽

Vol 11 (9) ◽

pp. 1767 ◽

Cited By ~ 5

Author(s):

S. Moe ◽

Raoul-Marie Couture ◽

Sigrid Haande ◽

Anne Lyche Solheim ◽

Leah Jackson-Blake

Keyword(s):

Climate Change ◽

Climatic Factors ◽

Synergistic Effects ◽

Ecological Status ◽

River Basin Management ◽

Catchment Management ◽

Model Framework ◽

Lake Ecosystems ◽

Chl A ◽

Cyanobacteria Blooms

Lake ecosystems across the world are under combined pressures of eutrophication and climate change, which increase the risk of harmful cyanobacteria blooms, reduced ecological status, and degraded ecosystem services. In Europe, the third cycle of river basin management plans (2021–2027) according to the Water Framework Directive must take into account the potential impacts of climate change on water quality, including effects on relevant biological indicators. Here, we applied a Bayesian network as a meta-model for linking future climate and land-use scenarios for the time horizon 2050–2070, via process-based catchment and lake models, to cyanobacteria abundance and ecological status of a eutrophic lake. Building upon previous applications of the model, a new version was developed to include relevant climatic variables such as wind speed. Explorative scenarios showed that the combination of low wind and high temperature gave the most synergistic effects on cyanobacteria under high levels of eutrophication (Chl-a concentration). Considering the management target of good ecological status, however, the climate-related promotion of cyanobacteria blooms contributed most to degrading the ecological status at intermediate levels of eutrophication. Future developments of this model will aim to strengthen the link between climate variables and ecological responses, to make the model also useful for seasonal forecasting.

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Assessing impacts of future climate change on hydrological processes in an urbanizing watershed with a multimodel approach

Journal of Water and Climate Change ◽

10.2166/wcc.2020.142 ◽

2020 ◽

Author(s):

Jian Sha ◽

Yue Zhao ◽

Xue Li ◽

Zhong-liang Wang

Keyword(s):

Climate Change ◽

Synergistic Effects ◽

Northwest China ◽

Hydrological Processes ◽

Future Climate Change ◽

Research Station ◽

Combined Application ◽

Study Results ◽

Urbanizing Watershed ◽

Ashton Research Station

Abstract The sensitivity of hydrological processes to the changed environment is of great concern. The integrated impacts of climate change and urbanization in the future have been assessed in a watershed in Northwest China through a multimodel approach based on the combined application of Generalized Watershed Loading Functions, the Long Ashton Research Station Weather Generator, and the Land Change Modeler. The results showed that both climate change and urbanization would lead to more watershed streamflow, and their combination would have synergistic effects on additional increases. In addition, there would be different seasonal distributions of streamflow with a greater proportion of runoff. These study results are helpful in supporting projects and/or decision-making processes for managers by providing more insights into the regional hydrological changes affected by climate change and urbanization. The proposed methodology of the combined multimodel approach may be applicable in other areas with similar conditions.

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Impacts of Recent Climate Change on Potato Yields at a Provincial Scale in Northwest China

Agronomy ◽

10.3390/agronomy10030426 ◽

2020 ◽

Vol 10 (3) ◽

pp. 426

Author(s):

Qiang Li ◽

Suiqi Zhang

Keyword(s):

Climate Change ◽

Climatic Factors ◽

Moving Average ◽

Northwest China ◽

Climatic Factor ◽

Potato Yield ◽

Maximum Temperature ◽

Recent Climate ◽

Potato Yields ◽

Provincial Scale

Understanding the effects of climate change on potato yield is vital for food security in northwest China. Based on the long-term data of yields and meteorology, this study analysed the impacts of recent climate change on potato yields at a provincial scale in northwest China. The first difference method was used to disentangle the contributions of climate change from the changes in potato yield in two consecutive years. The moving average method was used to decouple the climate-induced yield of potato. The results showed that the yield and planting area of potato from the period 1982 to 2015 increased markedly, with inter-annual fluctuations. The temperature increased significantly during the potato growing period in northwest China, while other climatic factors did not change significantly. Specifically, the changing trends in climatic factors varied among different provinces. The key meteorological factors limiting potato yield were temperature, precipitation and diurnal temperature range, varying in the different provinces. Potato yields in Gansu, Shaanxi, Ningxia and Xinjiang decreased by 127, 289, 199 and 339 kg ha−1, respectively, for every 1 °C increase in daily maximum temperature. The potato yield in Xinjiang decreased by 583 kg ha−1 for every 1 °C increase in daily minimum temperature. For every 100 mm increase in precipitation, the potato yields in Gansu, Qinghai and Ningxia increased by 250, 375 and 182 kg ha−1, respectively. Combining the first difference method and the moving average method, precipitation was the dominant climatic factor affecting potato yield in rain-fed areas (Gansu, Qinghai and Ningxia). For areas with irrigation (Xinjiang) or relatively high rainfall (Shaanxi), maximum temperature was the deciding climatic factor affecting potato yield. Appropriate adaptation to climate change in the different regions will help to ensure potato production in northwest China.

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Seasonal and Inter-Annual Variability of Groundwater and Their Responses to Climate Change and Human Activities in Arid and Desert Areas: A Case Study in Yaoba Oasis, Northwest China

Water ◽

10.3390/w12010303 ◽

2020 ◽

Vol 12 (1) ◽

pp. 303 ◽

Cited By ~ 4

Author(s):

Huanhuan Li ◽

Yudong Lu ◽

Ce Zheng ◽

Xiaonan Zhang ◽

Bao Zhou ◽

...

Keyword(s):

Climate Change ◽

Groundwater Level ◽

Human Activities ◽

Climatic Factors ◽

Groundwater Resources ◽

Principal Component ◽

Northwest China ◽

Warming Trend ◽

Trend Test ◽

Quantitative Calculation

Climate change and human activities have profound effects on the characteristics of groundwater in arid oases. Analyzing the change of groundwater level and quantifying the contributions of influencing factors are essential for mastering the groundwater dynamic variation and providing scientific guidance for the rational utilization and management of groundwater resources. In this study, the characteristics and causes of groundwater level in an arid oasis of Northwest China were explored using the Mann–Kendall trend test, Morlet wavelet analysis, and principal component analysis. Results showed that the groundwater level every year exhibited tremendous regular characteristics with the seasonal exploitation. Meanwhile, the inter-annual groundwater level dropped continuously from 1982 to 2018, with a cumulative decline depth that exceeded 12 m, thereby causing the cone of depression. In addition, the monthly groundwater level had an evident cyclical variation on the two time scales of 17–35 and 7–15 months, and the main periodicity of monthly level was 12 months. Analysis results of the climatic factors from 1954 to 2018 observed a significant warming trend in temperature, an indistinctive increase in rainfall, an inconspicuous decrease in evaporation, and an insignificant reduction in relative humidity. The human factors such as exploitation amount, irrigated area, and population quantity rose substantially since the development of the oasis in the 1970s. In accordance with the quantitative calculation, human activities were decisive factors on groundwater level reduction, accounting for 87.79%. However, climate change, including rainfall and evaporation, which contributed to 12.21%, still had the driving force to change the groundwater level in the study area. The groundwater level of Yaoba Oasis has been greatly diminished and the ecological environment has deteriorated further due to the combined effect of climate change and human activities.

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Impact of climate change and human activity on the runoff in the upper reaches of the Shiyang River, Northwest China

10.7287/peerj.preprints.187v1 ◽

2014 ◽

Author(s):

Peng Li ◽

Jianhua Xu ◽

Zhongsheng Chen ◽

Benfu Zhao

Keyword(s):

Climate Change ◽

Human Activity ◽

Climatic Factors ◽

Meteorological Data ◽

Northwest China ◽

Potential Evaporation ◽

The Past ◽

Shiyang River Basin ◽

Runoff Change ◽

Increasing Trend

Based on the hydrological and meteorological data of the upper reaches of Shiyang River basin in Northwest China from 1960 to 2009, this paper analyzed the change in runoff and its related climatic factors, and estimated the contribution of climate change and human activity to runoff change by using the moving T test, cumulative analysis of anomalies and multiple regression analysis. The results showed that temperature revealed a significant increasing trend, and potential evaporation capacity decreased significantly, while precipitation increased insignificantly in the past recent 50 years. Although there were three mutations in 1975, 1990 and 2002 respectively, runoff presented a slight decreasing trend in the whole period. The contributions of climate change and human activity to runoff change during the period of 1976-2009 were 45% and 55% respectively.

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Multi-Site Evaluation of Accumulated Temperature and Rainfall for Maize Yield and Disease in Loess Plateau

Agriculture ◽

10.3390/agriculture11040373 ◽

2021 ◽

Vol 11 (4) ◽

pp. 373

Author(s):

Xiaoyue Wang ◽

Xinghua Zhang ◽

Mingxian Yang ◽

Xiaonan Gou ◽

Binbin Liu ◽

...

Keyword(s):

Climate Change ◽

Significant Positive Correlation ◽

Climatic Factors ◽

Meteorological Data ◽

Maize Yield ◽

Future Climate Change ◽

Maize Production ◽

Positive Correlation ◽

Growing Period ◽

Accumulated Temperature

The Guanzhong region is a typical and important grain-producing area in China. The effect of accumulated temperature and rainfall on maize production is important in the face of global warming. Here, we collected meteorological data from six test sites in the Guanzhong region to study climate change from 1972 to 2018 in this area. A two-year study was conducted at multiple experimental sites to analyze the effect of climatic factors on maize yield and disease in the Guanzhong region. In the past 40 years, average temperatures have significantly increased at all sites, except for Hancheng. Rainfall varied significantly between years at each site, except for Huxian, with an overall declining trend. Accumulated temperature had a significant positive effect on yield (R2 = 0.28, p = 0.041 < 0.05), but rainfall did not affect yield (R2 = 0.0971, p = 0.324 > 0.05). During the growing period, total rainfall had a significant positive correlation with northern leaf blight disease in maize, and rainfall before silking had a significant positive correlation with ear length and row grain number. The demand for accumulated temperature by maize differed between sites. It is predicted that maize yield will increase with increasing temperature in the Guanzhong region. Greater attention should be paid to improve agronomic practices, such as adjustment of sowing dates, straw mulching, deep tillage, and pest control to adapt to future climate change.

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Contrasting Evolution Patterns of Endorheic and Exorheic Lakes on the Central Tibetan Plateau and Climate Cause Analysis during 1988–2017

Water ◽

10.3390/w13141962 ◽

2021 ◽

Vol 13 (14) ◽

pp. 1962

Author(s):

Zhilong Zhao ◽

Yue Zhang ◽

Zengzeng Hu ◽

Xuanhua Nie

Keyword(s):

Climate Change ◽

Tibetan Plateau ◽

Climatic Factors ◽

Global Climate ◽

Rapid Expansion ◽

Annual Precipitation ◽

The Tibetan Plateau ◽

Lake Area ◽

Climate Change Research ◽

Mean Temperature

The alpine lakes on the Tibetan Plateau (TP) are indicators of climate change. The assessment of lake dynamics on the TP is an important component of global climate change research. With a focus on lakes in the 33° N zone of the central TP, this study investigates the temporal evolution patterns of the lake areas of different types of lakes, i.e., non-glacier-fed endorheic lakes and non-glacier-fed exorheic lakes, during 1988–2017, and examines their relationship with changes in climatic factors. From 1988 to 2017, two endorheic lakes (Lake Yagenco and Lake Zhamcomaqiong) in the study area expanded significantly, i.e., by more than 50%. Over the same period, two exorheic lakes within the study area also exhibited spatio-temporal variability: Lake Gaeencuonama increased by 5.48%, and the change in Lake Zhamuco was not significant. The 2000s was a period of rapid expansion of both the closed lakes (endorheic lakes) and open lakes (exorheic lakes) in the study area. However, the endorheic lakes maintained the increase in lake area after the period of rapid expansion, while the exorheic lakes decreased after significant expansion. During 1988–2017, the annual mean temperature significantly increased at a rate of 0.04 °C/a, while the annual precipitation slightly increased at a rate of 2.23 mm/a. Furthermore, the annual precipitation significantly increased at a rate of 14.28 mm/a during 1995–2008. The results of this study demonstrate that the change in precipitation was responsible for the observed changes in the lake areas of the two exorheic lakes within the study area, while the changes in the lake areas of the two endorheic lakes were more sensitive to the annual mean temperature between 1988 and 2017. Given the importance of lakes to the TP, these are not trivial issues, and we now need accelerated research based on long-term and continuous remote sensing data.

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Assessing the Sensitivity of Main Crop Yields to Climate Change Impacts in China

Atmosphere ◽

10.3390/atmos12020172 ◽

2021 ◽

Vol 12 (2) ◽

pp. 172

Author(s):

Yuan Xu ◽

Jieming Chou ◽

Fan Yang ◽

Mingyang Sun ◽

Weixing Zhao ◽

...

Keyword(s):

Climate Change ◽

Crop Yield ◽

Food Production ◽

Crop Yields ◽

Climatic Factors ◽

Climatic Data ◽

The South ◽

The North ◽

Output Elasticity ◽

The Impact

Quantitatively assessing the spatial divergence of the sensitivity of crop yield to climate change is of great significance for reducing the climate change risk to food production. We use socio-economic and climatic data from 1981 to 2015 to examine how climate variability led to variation in yield, as simulated by an economy–climate model (C-D-C). The sensitivity of crop yield to the impact of climate change refers to the change in yield caused by changing climatic factors under the condition of constant non-climatic factors. An ‘output elasticity of comprehensive climate factor (CCF)’ approach determines the sensitivity, using the yields per hectare for grain, rice, wheat and maize in China’s main grain-producing areas as a case study. The results show that the CCF has a negative trend at a rate of −0.84/(10a) in the North region, while a positive trend of 0.79/(10a) is observed for the South region. Climate change promotes the ensemble increase in yields, and the contribution of agricultural labor force and total mechanical power to yields are greater, indicating that the yield in major grain-producing areas mainly depends on labor resources and the level of mechanization. However, the sensitivities to climate change of different crop yields to climate change present obvious regional differences: the sensitivity to climate change of the yield per hectare for maize in the North region was stronger than that in the South region. Therefore, the increase in the yield per hectare for maize in the North region due to the positive impacts of climate change was greater than that in the South region. In contrast, the sensitivity to climate change of the yield per hectare for rice in the South region was stronger than that in the North region. Furthermore, the sensitivity to climate change of maize per hectare yield was stronger than that of rice and wheat in the North region, and that of rice was the highest of the three crop yields in the South region. Finally, the economy–climate sensitivity zones of different crops were determined by the output elasticity of the CCF to help adapt to climate change and prevent food production risks.

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A meta-analysis of the literature on climate change and migration

Journal of Demographic Economics ◽

10.1017/dem.2019.22 ◽

2021 ◽

pp. 1-52

Author(s):

Michel Beine ◽

Lionel Jeusette

Keyword(s):

Climate Change ◽

Climatic Factors ◽

Human Mobility ◽

Meta Analysis ◽

Empirical Studies ◽

Displacement Effect ◽

Methodological Choices ◽

Econometric Methods ◽

And Migration

Abstract Recent surveys of the literature on climate change and migration emphasize the important diversity of outcomes and approaches of the empirical studies. In this paper, we conduct a meta-analysis in order to investigate the role of the methodological choices of these empirical studies in finding some particular results concerning the role of climatic factors as drivers of human mobility. We code 51 papers representative of the literature in terms of methodological approaches. This results in the coding of more than 85 variables capturing the methodology of the main dimensions of the analysis at the regression level. These dimensions include authors' reputation, type of mobility, measures of mobility, type of data, context of the study, econometric methods, and last but not least measures of the climatic factors. We look at the influence of these characteristics on the probability of finding any effect of climate change, a displacement effect, an increase in immobility, and evidence in favor of a direct vs. an indirect effect. Our results highlight the role of some important methodological choices, such as the frequency of the data on mobility, the level of development, the measures of human mobility and of the climatic factors as well as the econometric methodology.

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