水利学报
水利學報
수리학보
2014年
7期
809-814
,共6页
孙可可%陈进%金菊良%郦建强%许继军%费振宇
孫可可%陳進%金菊良%酈建彊%許繼軍%費振宇
손가가%진진%금국량%역건강%허계군%비진우
农业旱灾%损失风险曲线%抗旱能力%干旱频率分析%脆弱性%水稻
農業旱災%損失風險麯線%抗旱能力%榦旱頻率分析%脆弱性%水稻
농업한재%손실풍험곡선%항한능력%간한빈솔분석%취약성%수도
agricultural drought%risk curve of loss%drought resistance%drought frequency analysis%vulner-ability%rice
基于前期研究提出的4种假定灌溉条件下季节性干旱频率-旱灾损失率定量关系曲线,针对不同频率干旱发生时来水条件存在的差异与实际抗旱能力的不同,研究在变化的实际抗旱能力下,农业季节性干旱频率和旱灾损失率之间的定量关系,以此计算出实际抗旱能力下农业旱灾损失风险曲线。首先,以干旱期间供水满足需水的比例作为抗旱能力指标,分别建立抗旱能力指标-来水频率、干旱频率-干旱烈度保证率之间的关系曲线,以干旱烈度保证频率表征来水频率,进而得出各次干旱过程的抗旱能力指标与干旱频率的一一对应关系。然后,利用Copula函数计算干旱频率,通过 EPIC模型模拟水稻产量并计算损失,建立干旱频率-假定灌溉水平-旱灾损失率三者间关系。最后,根据抗旱能力和干旱频率的对应关系,并以抗旱能力指标反映灌溉水平,可推得现状水平年实际抗旱能力下的干旱频率-旱灾损失率曲线。在湖南株洲市水稻旱灾损失风险计算的应用实例表明,实际抗旱能力下双季早稻夏季5-7月干旱频率-旱灾损失率之间,基本呈半对数函数趋势关系。对比历史旱灾损失调查结果,当发生2、5、10年一遇的干旱时,旱灾损失率的实际调查结果与理论计算值的相对差值分别为1.69%、-5.33%和-4.81%。
基于前期研究提齣的4種假定灌溉條件下季節性榦旱頻率-旱災損失率定量關繫麯線,針對不同頻率榦旱髮生時來水條件存在的差異與實際抗旱能力的不同,研究在變化的實際抗旱能力下,農業季節性榦旱頻率和旱災損失率之間的定量關繫,以此計算齣實際抗旱能力下農業旱災損失風險麯線。首先,以榦旱期間供水滿足需水的比例作為抗旱能力指標,分彆建立抗旱能力指標-來水頻率、榦旱頻率-榦旱烈度保證率之間的關繫麯線,以榦旱烈度保證頻率錶徵來水頻率,進而得齣各次榦旱過程的抗旱能力指標與榦旱頻率的一一對應關繫。然後,利用Copula函數計算榦旱頻率,通過 EPIC模型模擬水稻產量併計算損失,建立榦旱頻率-假定灌溉水平-旱災損失率三者間關繫。最後,根據抗旱能力和榦旱頻率的對應關繫,併以抗旱能力指標反映灌溉水平,可推得現狀水平年實際抗旱能力下的榦旱頻率-旱災損失率麯線。在湖南株洲市水稻旱災損失風險計算的應用實例錶明,實際抗旱能力下雙季早稻夏季5-7月榦旱頻率-旱災損失率之間,基本呈半對數函數趨勢關繫。對比歷史旱災損失調查結果,噹髮生2、5、10年一遇的榦旱時,旱災損失率的實際調查結果與理論計算值的相對差值分彆為1.69%、-5.33%和-4.81%。
기우전기연구제출적4충가정관개조건하계절성간한빈솔-한재손실솔정량관계곡선,침대불동빈솔간한발생시래수조건존재적차이여실제항한능력적불동,연구재변화적실제항한능력하,농업계절성간한빈솔화한재손실솔지간적정량관계,이차계산출실제항한능력하농업한재손실풍험곡선。수선,이간한기간공수만족수수적비례작위항한능력지표,분별건립항한능력지표-래수빈솔、간한빈솔-간한열도보증솔지간적관계곡선,이간한열도보증빈솔표정래수빈솔,진이득출각차간한과정적항한능력지표여간한빈솔적일일대응관계。연후,이용Copula함수계산간한빈솔,통과 EPIC모형모의수도산량병계산손실,건립간한빈솔-가정관개수평-한재손실솔삼자간관계。최후,근거항한능력화간한빈솔적대응관계,병이항한능력지표반영관개수평,가추득현상수평년실제항한능력하적간한빈솔-한재손실솔곡선。재호남주주시수도한재손실풍험계산적응용실례표명,실제항한능력하쌍계조도하계5-7월간한빈솔-한재손실솔지간,기본정반대수함수추세관계。대비역사한재손실조사결과,당발생2、5、10년일우적간한시,한재손실솔적실제조사결과여이론계산치적상대차치분별위1.69%、-5.33%화-4.81%。
Based on the relation curve of seasonal drought frequency and drought loss proposed in previous study under four different irrigation levels, the quantitative relationship between seasonal drought frequency and drought loss has been calculated to construct the drought loss risk curve, considering the changes of actual drought resistance ability with drought frequency. First, the ratio of water supply to meet the water demand in periods of drought was defined as drought resistance index. The relation curve between drought resistance index and inflow frequency, and the relation curve between drought frequency and guaranteed rate of drought intensity were established respectively, and then using guaranteed rate of drought intensity to express inflow frequency, the one-to-one relationship between drought resistance index and drought fre-quency of each drought process was obtained. Then,drought frequency can be calculated using Copula func-tion,the crop yield was simulated and yield loss rate under drought was computed using the Environmental Policy Integrated Climate Model, and the relations were set up among drought frequency, irrigation levels and drought loss rate. At last, the drought resistance index can express irrigation levels, the relation curve can be estimated between drought frequency and drought loss rate under the actual drought resistance abili-ty conditions, which can be regarded as agricultural drought loss risk curve. By applying the above calcula-tion method in Zhuzhou City of Hunan Province, the results show that the relation curves of drought fre-quency and drought loss rate of early rice during summer from May to July under the actual drought resis-tance ability conditions basically complies with semi-logarithmic function in line with trends in the relation-ship. In comparing with the history crop yield losses of drought, when 2-year, 5-year and 10-year return droughts take place, the relative errors of the actual survey results and theoretical computation values of drought loss rate are 1.69%,-5.33% and -4.8%,respectively.