中国农业气象
中國農業氣象
중국농업기상
AGRICULTURAL METEOROLOGY
2015年
3期
331-337
,共7页
风险价值%概率分布%优度检验%旱灾风险评估%甘肃省
風險價值%概率分佈%優度檢驗%旱災風險評估%甘肅省
풍험개치%개솔분포%우도검험%한재풍험평고%감숙성
Value at risk%Probability distribution%Goodness of fit test%Risk assessment of drought%Gansu province
利用甘肃省农作物旱灾受灾面积、成灾面积、绝收面积、播种面积及单位面积产量数据,计算农业旱灾损失率,根据优度检验结果拟合旱灾损失率最优概率分布模型,并借鉴经济学风险价值(VaR)方法,强调在统计意义下不同等级旱灾的风险水平,实现对甘肃省农业旱灾风险的有效度量。结果表明：1950－2011年旱灾对甘肃省农业生产的影响相对有限,农业旱灾损失率均在30％以下,平均10％左右,损失率的年际变化呈增长趋势,1995年因旱致灾损失率最大,达26.8％；近62a 甘肃省农业旱灾损失率的最优概率分布模型为广义极值(Gen. Extreme Value,GEV)分布模型；全省面临10a 一遇的旱灾时农业损失率为18.8％,遭遇50a 一遇的旱灾时农业损失率为25.7％,遭遇100a 一遇的极端旱灾时农业损失率高达28.3％,即全省农业产量或粮食产量将面临减少近30％的风险,这将给甘肃省粮食生产带来严峻考验。
利用甘肅省農作物旱災受災麵積、成災麵積、絕收麵積、播種麵積及單位麵積產量數據,計算農業旱災損失率,根據優度檢驗結果擬閤旱災損失率最優概率分佈模型,併藉鑒經濟學風險價值(VaR)方法,彊調在統計意義下不同等級旱災的風險水平,實現對甘肅省農業旱災風險的有效度量。結果錶明：1950－2011年旱災對甘肅省農業生產的影響相對有限,農業旱災損失率均在30％以下,平均10％左右,損失率的年際變化呈增長趨勢,1995年因旱緻災損失率最大,達26.8％；近62a 甘肅省農業旱災損失率的最優概率分佈模型為廣義極值(Gen. Extreme Value,GEV)分佈模型；全省麵臨10a 一遇的旱災時農業損失率為18.8％,遭遇50a 一遇的旱災時農業損失率為25.7％,遭遇100a 一遇的極耑旱災時農業損失率高達28.3％,即全省農業產量或糧食產量將麵臨減少近30％的風險,這將給甘肅省糧食生產帶來嚴峻攷驗。
이용감숙성농작물한재수재면적、성재면적、절수면적、파충면적급단위면적산량수거,계산농업한재손실솔,근거우도검험결과의합한재손실솔최우개솔분포모형,병차감경제학풍험개치(VaR)방법,강조재통계의의하불동등급한재적풍험수평,실현대감숙성농업한재풍험적유효도량。결과표명：1950－2011년한재대감숙성농업생산적영향상대유한,농업한재손실솔균재30％이하,평균10％좌우,손실솔적년제변화정증장추세,1995년인한치재손실솔최대,체26.8％；근62a 감숙성농업한재손실솔적최우개솔분포모형위엄의겁치(Gen. Extreme Value,GEV)분포모형；전성면림10a 일우적한재시농업손실솔위18.8％,조우50a 일우적한재시농업손실솔위25.7％,조우100a 일우적겁단한재시농업손실솔고체28.3％,즉전성농업산량혹양식산량장면림감소근30％적풍험,저장급감숙성양식생산대래엄준고험。
The loss rate of agricultural drought was calculated, based on the data of crops area covered by drought disaster, affected by drought disaster, and no harvest by drought disaster, and crops yield data as well. The best probability model of drought loss rate was established, according to the goodness of fit test result. The agricultural drought disaster risk in Gansu province was assessed referring to value at risk (VaR) from economics and different levels of drought risk. The results showed that the effect of drought on agricultural production in Gansu province from 1950 to 2011 was relative limited, and the loss rate of agricultural drought was no more than 30% , with an average of 10% . The max loss rate occurred in 1995, with the rate of 26. 8% . The best probability model of drought loss rate was generalized extreme value (GEV) model in Gansu province in last 62 years. The agricultural loss rate was 18. 8% if facing drought once of ten years, 25. 7% facing drought once of 50 years, and 28. 3% facing drought once of 100 years.
