Effects of Droughts and Floods on Crops and Preventions in Puyang City

Hanjin LI,Chong GAO,Wenguo XU,Zhijun GAO

Puyang Meteorological Bureau,Puyang 457000,China

Effects of Droughts and Floods on Crops and Preventions in Puyang City

Hanjin LI*,Chong GAO,Wenguo XU,Zhijun GAO

Puyang Meteorological Bureau,Puyang 457000,China

The research analyzed characters of rice/wheat growth and yield structure in Puyang and explored the effects of droughts and floods on the crops.The results showed that droughts and floods had significant effects on crop growth and yield.In Puyang,the relieving and prevention technology of the disasters is concluded.Specifically,it is recommended to make full use of agricultural climate resources in a rational way and select suitable crop varieties according to climate and disaster characters,followed by timely sowing and scientific crop arrangement. What's more,ploughing should proceed in deeper soil layers and management measures should be optimized to reduce the effects of disasters on crops.In addition to that,disaster index system should be reinforced in terms of establishment, monitoring,warning and prevention to lay scientific foundations and provide references for safe crop production and preventing and reducing disasters.

Droughts and floods;Rice and wheat;Growth and development;Damage influence;Optimization prevention

P uyang City is a core area of crop production in Henan Province,where wheat and rice are staple food[1]in terms of sowing area or yield.Recently,both of crop price and planting area keep growing,and it is of significance for achieving high yields to maintain high and stable yield of rice and wheat.

Puyang City is located in the east of the Yellow River and has a temperate semi-arid continental monsoon climate,with four distinct seasons. Besides,extreme weathers,such as droughts and floods,occur frequently, resulting in destructions on crops in varying degrees and areas yearly. Therefore,it is important for accomplishing stable yield and improving farmer’s incomes to analyze the effects of meteorological disaster on crop growth and yield and explore scientific countermeasures against meteorological disasters to reduce or avoid the adverse effects.

Damages of Droughts and Floods on Crops in Puyang City

Drought

In Puyang City,annual mean precipitation keeps in the range of 500 to 600 mm,which suggests that water resources are relatively lower,and therefore,droughts are prone to occurring throughout the year.What’s worse,the area by manual irrigation is uneven in Puyang(Fig.1)and droughts in some regions can not be relieved on time,leading to insufficient water of soils,which would affect seedling germination and deficiency of water in crops.Consequently,crop growth would be affected,involving few tillers and small plants,and even dead plants,under influence of meteorological disasters,especially for spring, summer and autumn droughts.

Spring droughtAccording to meteorological index of spring drought(total

Summer droughtEarly summer drought mainly affects grain filling of wheat,weight growth of seeds,crop sowing and seedling growth,and droughts during hot summer mainly influences earing,flowering and pollination in autumn.

Autumn droughtAutumn drought mainly occurs in September-December,and the occurring rate reaches 51%according to autumn drought index(total precipitation≤30 mm with rains for 40 successive days).It is notable that autumn drought mainly affects grain filling of seeds and wheat sowing and germination.

Rain floods

Rain flood,caused by rainstorm and continuous rain,is one of major meteorological disasters in Puyang City,which affects harvest of wheat. For example,rain floods would prevent root extending,resulting in poor tillering capacity,weak plant,thin stem,low earing rate,a small number of seed, and lowering of seed weight.As for rice,seedling regeneration would slow down,leaf would turn yellow,root decay and plant die.Besides,the number of tiller would reduce,and growth environment would go poorer;the peak-tillering stage would postpone upon growth term.What’s worse,as grain filling stops,the sterile spikelet rate would grow,and thousand-seed weight would decline.In addition,the longer flooding,the more serious the damages.

RainstormRainstorm is one of the most serious and frequent meteorological disasters in Puyang.It might occur in spring,summer and autumn in varying degrees,with uneven distribution,temporally or spatially(Fig.2).

Continuous rainContinuous raining refers to raining processes with raining for 5 or more successive days and precipitation over 30mm.In Puyang City,continuous rainy days usually occur for 5 or 6 times.Consequently, crop photosynthesis would be prevented and crop quality and yield would be under influence as well.

Optimized Countermeasures and Technologies Against Droughts and Floods for Crops in Puyang

Prevention measures against droughts of winter wheat

The measures of protecting winter wheat from droughts include to select suitable species according to the type of year,to irrigate abundant available soil water at planting,to increase fertilizers,to plough farmlands deeply to increase permeation depth and enhance moisture storage,to irrigate in the period of seedling establishment and jointing stage in a limited way and to spray drought preventing agents.

Prevention measures against droughts of riceThe prevention measures include to select high-tolerance species against droughts according to local conditions,to cultivate seedlings with high resistance to droughts in arid or semi-arid fields,because the seedlings take advantage in rooting,and thick leaf,to dig holes for planting,followed by irrigation(If seedlings ripen and hard to be transplanted,the seedlings can be planted in fields with water in case of seedling aging in jointing stage,followed by growing after rainfalls)and to evenly extend grasses and tree leaves on paddy fields to prevent moisture evaporation.

Optimization and prevention measures at rain-waterlogging

Prevention measures of waterlogging for wheatIt is necessary to conduct drainage project with supporting facilities in order to control water level of inland rivers and guarantee water draining.

The plough layers should be deepened and moisture content of soils be adjusted by rational arrangement of crops and the same crop variety in order to advance root development.

The crop variety with resistance to humidity can be chosen to intensify humidity tolerance of wheat.

The growth regulatory substance should be sprayed to delay senescence and reduce flood damages[5].

Prevention measures of waterlogging for riceIt is recommended to construct flood control projects and drainage of stagnant water should be conducted timely at flooding.

The compactly-growing rice varieties with strong roots and stems,and high regeneration capacity should be chosen.

The farming system and intercropping varieties can be well arranged according to flood degree, supplemented by cultivation management to reduce flood damages to anextreme.

During seedling stage,drainage of stagnant water should be conducted timely in case of death by suffocation of seedlings.

If the flood is so serious on a hot day,it is not recommended to drain water once.Instead,the rice should be guaranteed with a resuming and adaption process in case of withering because of transpiration.After water draining,readily available fertilizers can be supplemented to promote seedling growth.

Finally,the control of floodcaused diseases or pests should be always well-prepared.

Conclusions and Strategies

To strengthen agricultural disaster prevention and mitigation system

Disaster prevention and mitigation system consists of works before,in and after a disaster.It is urgent to establish an overall and prefect agricultural reduction and prevention system of agro-meteorological hazard according to causes and characters of local disasters.

To improve unified releasing system of agro-meteorological early warnings

Considering rural areas are fragile in preventing meteorological disasters, it is necessary to establish an effective coordination and communication system to enhance the prevention capacity and mitigate or prevent disasters.

To conduct afforestation and improve vegetation coverage

Forestlands promote soil taking in water and rich forests effectively reduce surface runoffs,so that rain water directly and rapidly permeate into soils,which decreases water evaporation from farmlands and improve local environment.

To adjust planting structure and intensify field management

It is suggested to take scientific and practical measures to reduce meteorological calamity degree and to avoid the sensitive phases of crops, such as flooding period,depending on drought-resistant cultivations to grow new varieties,in order to avert unneccesary loss based on rational and scientific planting.

[1]ZHENG DW(郑大玮),ZHENG DQ(郑大琼),LIU HC(刘虎城).The technological manual of agricultural disaster reduction(农业减灾实用技术手册)[M]. Hangzhou:Zhejiang Science&Technology Press(杭州:浙江科学技术出版社),2005.

[2]LIU RH(刘荣花),FANG WS(方文松), ZHU ZX(朱自玺),et al.Distribution pattern of availablesoil water at planting for winter wheat in Huanghuai plain(黄淮平原冬小麦底墒水分布规律)[J].Chinese Journal of Ecology(生态学杂志),2008, 27(12):2105-2110.

[3]YU WD(余卫东),ZHAO GQ(赵国强), CHEN HL(陈怀亮).Impacts of climate change on growing stages of main crops in Henan province(气候变化对河南省主要农作物生育期的影响)[J].Chinese Journal of Agrometeorology(中国农业气象),2007,28(1):9-12.

[4]CHENG SH(程式华),LI J(建).China rice at modern times(现代中国水稻)[M]. Beijing:Jindun Press(北京:金盾出版社),2007.

[5]GUO XM(郭宪美),ZHANG JT(张金同), QU TH(曲同华).Analysis of flooding causes and measures of remediation of autumn crops(秋作物洪涝成因分析及灾后补救措施)[J].Journal of Anhui Agricultural Sciences(安徽农业科学),2014, 42(8):2352-2353.

Responsible editor:Xiaoxue WANG

Responsible proofreader:Xiaoyan WU

濮阳旱涝灾害对稻麦类作物的影响及优化防御

李汉浸*，高翀，徐文国，高志军
（河南省濮阳市气象局，河南濮阳457000）

分析了影响濮阳稻麦类作物生长发育和产量结构的旱涝灾害特点，探讨了不同程度灾害对稻麦类作物生长的危害，结果表明，旱涝灾害对稻麦类作物生长和产量危害较大，往往会影响到稻麦类作物产量的丰、欠。濮阳稻麦类作物"旱、涝"灾害的缓解防御技术主要是对灾害的"避、抗、减、补"，要合理利用农业气候资源，根据气候和灾害特点，选适宜品种，适时播种、合理作物布局，加深耕作层，等耕作方式和优化管理措施，从而减少灾害对作物的影响；并有针对性地加强旱涝灾害指标体系建立、监测、预警和防御，为确保粮食生产安全和防灾减灾提供提供科学基础和指导依据。

旱涝灾害；稻麦作物；生长发育；危害影响；优化防御precipitation≤30 mm,with rains for 50 successive days during March-May), spring drought occurred in most years (60%),affecting wheat growth in spring and crop sowing in autumn.

李汉浸（1965-），男，河南滑县人，高级工程师，主要从事农业气象业务科研工作，E-mail：hnpylhq@126.com。*通讯作者。

2015-04-04

修回日期 2015-05-14

*Corresponding author.E-mail:hnpylhq@126.com

Received:April 4,2015 Accepted:May 15,2015