What impact will the temperature rise have on China's agricultural production?
what impact will climate warming bring to agricultural production? Is it good or bad? The reporter interviewed relevant experts for this purpose. Song Lianchun, director of the Department of Forecasting and Disaster Reduction of China Meteorological Bureau, said that the high temperature in winter will have a double impact on agricultural production. High temperature is conducive to the overwintering of eggs and bacteria, which is easy to lead to the spread of pests and diseases in spring. At the same time, due to the dry winter climate in the northern region, it will also cause soil moisture loss, which may lead to spring drought in some areas. On the other hand, the high temperature is conducive to the accumulation of land heat and has a favorable impact on the growth and development of winter crops such as rape in the south. The analysis of experts from Heilongjiang Biological Control Station also shows that climate warming provides favorable conditions for the survival of germs and the overwintering of pests, which is likely to bring very adverse effects on agricultural production in the spring of 27.
The El Niñ o phenomenon caused by climate warming has a deeper impact on agricultural production. Climate experts said that in the event of El Niñ o, China often suffers from drought in the south and drought in the north, and the probability of high temperature in winter is greater. 1998 is a typical "El Niñ o year". According to the monitoring of the meteorological department of Jiangsu Province, from December last year to January this year, the temperature in this province was obviously high, which was obviously influenced by El Niñ o. Climate experts believe that under the influence of El Niñ o phenomenon, continuous rainy weather is prone to occur in spring, which affects the growth of food crops and even leads to reduced production.
Not long ago, the National Assessment Report on Climate Change issued by the Ministry of Science and Technology, China Meteorological Bureau, China Academy of Sciences and other six departments pointed out that it is likely that the national average temperature will increase by 2 to 3 degrees Celsius in the next 5 to 8 years, and the average precipitation will increase by 7% to 1%, but it will not change the trend of drought, especially in the north. As climate warming increases agricultural water demand, regional differences in water supply will also increase. In order to adapt to changes in production conditions, agricultural costs and investment needs will increase substantially.
Climate experts say that climate change will have a great impact on agricultural production in China. If no measures are taken, the output of major crops in China, such as wheat, rice and corn, will drop by 37% at most by the second half of the 21st century. In animal husbandry, the trend of drought caused by climate change will increase the potential desertification trend in semi-arid areas, the grassland boundary may be expanded, the area of alpine grassland will be reduced, and the distribution pattern of grassland carrying capacity and livestock carrying capacity will change greatly.
according to the forecast of the national climate center, the temperature in most parts of China in February was close to normal or higher, and there was more precipitation in northern and western Xinjiang, central and western Inner Mongolia, central and eastern Gansu, Ningxia, eastern Qinghai, most of the middle and lower reaches of the Yangtze River, central and western Jiangnan and eastern Southwest China. Meteorologists suggest that livestock in northwest and Inner Mongolia pastoral areas should strengthen cold and warmth, prevent snowstorms and other disasters in pastoral areas, and ensure the safety of weak livestock and young livestock in wintering. Since January, there has been less rain and snow in most winter wheat areas in the north, and the moisture content has declined. All localities should prepare for drought as soon as possible to avoid spring drought. "beginning of spring" is approaching, all localities should timely harrow wheat and intertillage to conserve moisture according to the weather changes, and apply organic fertilizer in areas where conditions permit, so as to increase the temperature and conserve moisture and promote the timely growth of winter wheat.
Experts say that the high temperature and warm autumn caused by climate warming last summer affected China's agricultural production
Xinhua News Agency, Beijing, February 2 (Reporter Wang Yu) Global warming caused by human activities is having more and more impacts on agricultural production. Lv Houquan, an expert in ecology and agrometeorology at the National Meteorological Center, said in an interview that the drought and high temperature in Sichuan and Chongqing last year and the high temperature in most autumn and winter crop areas had a great impact on crop growth.
Lv Houquan said that the severe weather that had a great impact on China's agricultural production in 26 was mainly the summer drought and high temperature in Sichuan and Chongqing. The summer drought in Chongqing and Sichuan are the worst years since 1951, respectively, with the characteristics of early occurrence, long duration, wide range, strong disaster intensity and serious harm. The beginning of summer drought appeared in early July, 1 ~ 2 days earlier than normal, and it didn't end until early September.
Lu Houquan said that the unusually high temperature in summer is the main factor leading to the rapid development of drought and the aggravation of its damage. In 26, the number of days with high temperature exceeding 35 degrees Celsius was 3 ~ 55 in most dry areas, and the number of days with high temperature exceeding 4 degrees Celsius in some areas reached more than 1 days, even exceeding 44 degrees Celsius. The degree of less precipitation, duration and intensity of high temperature in eastern Sichuan and most parts of Chongqing from July to mid-August all reached the extreme value of the same period since meteorological records were recorded. The intensity and scope of drought are obviously greater than in previous years, which has spread to 122 counties and cities in Sichuan and 34 districts and counties in Chongqing, covering almost the whole Sichuan basin, and its intensity, scope and duration have exceeded the same period in history. Crops suffer from high temperature and drought, which leads to poor fruiting and filling, and the grain yield is reduced by more than 5 million tons. The yield and quality of cash crops have also declined. At the same time, the agricultural infrastructure is also seriously damaged, which has a great negative impact on the sustainable development of agriculture.
Lv Houquan said that the temperature in most winter crop areas in China in autumn 26 was significantly higher than that in the same period of normal years. The warm autumn made the wheat in the northern winter wheat area grow faster before winter, and some areas showed vigorous growth and poor cold resistance, which may lead to freezing injury in case of strong cooling. Especially in some areas with poor soil moisture, wheat fields can not be sealed tightly, and when there is strong wind to cool down, it is easy to form freezing damage.
The summary of the fourth climate change assessment report released by the United Nations says that global warming is an indisputable fact
Xinhua News Agency, Paris, February 2 (Reporter Lu Suyan) Climate warming is an indisputable fact, and human activities are probably the main cause of climate warming. This is the main conclusion of the fourth climate change assessment report issued by the United Nations Intergovernmental Panel on Climate Change (IPCC) on the 2nd.
The above conclusions provide a theoretical basis for decision makers all over the world to determine effective measures to protect the environment as soon as possible. Experts pointed out in the summary of the report, which is more than 2 pages long, that the observation of the global average atmospheric temperature, the average ocean temperature, the melting of glaciers and snow, and the measurement of global sea level have confirmed that the global climate is warming.
experts predict that from now until 21, the "most likely increase range" of the global average temperature will be 1.8-4 degrees Celsius, and the sea level will rise by 18-59 centimeters, and the reason for this trend is "very likely", that is, at least 9% may be human activities.
According to the summary of the report, since 175, the global contents of carbon dioxide, methane and nitrous oxide have been increasing at an alarming rate, which has far exceeded the level before the industrial revolution. The increase of carbon dioxide is mainly caused by human use of fossil fuels, while the increase of methane and nitrous oxide is mainly due to human agricultural production activities.
Zheng Guoguang, deputy director of the China Meteorological Bureau and co-chairman of the International Earth Observation Organization, said that the synopsis published today integrates the scientific research achievements of scientists all over the world for more than six years, which is more scientific and less uncertain than the third climate change assessment report published in 21.
taking the prediction of sea level rise as an example, he said that when the third assessment report was drafted, the scientific community was based on only a few experiments, but this time it was based on 58 experiments conducted by 11 countries using 14 climate assessment models. In addition, the forecast range of global temperature rise has also been significantly reduced, which shows that the scientific community's scientific understanding of climate change has been greatly improved. In the third assessment report, experts predicted that by 21, the global average temperature would rise by 1.4 to 5.8 degrees Celsius, and the sea level would rise by 9 to 88 centimeters.
From January 29th to February 1st, more than 5 experts from IPCC Working Group I met in Paris to revise the fourth assessment report of the IPCC and draft the outline of the assessment report. Qin Dahe, director of China Meteorological Bureau, presided over the meeting as the co-chairman of IPCC.
during this meeting, many cities, such as Paris, the French capital, turned off their lights and electricity for five minutes on the evening of February 1, in order to declare war on energy waste. The Eiffel Tower turned off all lighting equipment, and buildings such as museums belonging to the city of Paris were also blacked out.
IPCC was founded by the United Nations Environment Programme and the World Meteorological Organization in 1988. It has gathered more than 2,5 experts from all over the world, and the committee is divided into three working groups. So far, IPCC has published three assessment reports on global climate change. The full text of the fourth assessment report will be published in the second half of this year.