涇河流域自然災(zāi)害風險分析

涇河流域自然災(zāi)害風險分析引言生態(tài)安全（ecologicalsafety）國際應(yīng)用系統(tǒng)分析研究所（IASA）：指在人的生活、健康、資源、適應(yīng)環(huán)境變化的能力等方面不受威脅。生態(tài)安全的理論和研究方法處在發(fā)展階段。生態(tài)風險（ecologicalrisk）從相反的方向刻畫生態(tài)安全（肖篤寧，2002），是在一個特定的生態(tài)系統(tǒng)中所發(fā)生的一個或多個不良事件的概率及其嚴重后果（損失）。對生態(tài)系統(tǒng)進行風險分析是生態(tài)安全定量研究的核心內(nèi)容之一。盡管目前缺少可以借鑒的流域或區(qū)域尺度上的生態(tài)系統(tǒng)風險風險的案例。自然災(zāi)害是涇河流域面臨的重要生態(tài)風險之一,自然災(zāi)害的發(fā)生對涇河流域生態(tài)系統(tǒng)的結(jié)構(gòu)、功能都存在著極大的威脅，一旦發(fā)生對生態(tài)系統(tǒng)造成損害，從而危及流域生態(tài)系統(tǒng)及其內(nèi)部組分的安全和健康。研究思路分析涇河流域存在的主要自然災(zāi)害。進行單因子自然災(zāi)害生態(tài)風險源分析。構(gòu)建自然災(zāi)害生態(tài)風險綜合評價模型對涇河流域自然災(zāi)害生態(tài)風險進行整體評價，從而流域生態(tài)系統(tǒng)管理提出對策。數(shù)據(jù)來源涇河流域慶陽地區(qū)縣域單元的自然災(zāi)害統(tǒng)計數(shù)據(jù)（旱災(zāi)、水災(zāi)、風災(zāi)、雹災(zāi)、霜凍災(zāi)、病蟲災(zāi)）慶陽縣（1950-2001）鎮(zhèn)原縣（1950-2001）合水縣（1950-2001）寧縣（1950-2001）正寧縣（1950-2001）華池縣（1950-2001）環(huán)縣（1950-2001）西峰市（1986-2001）研究方法研究區(qū)概況統(tǒng)計方法1受災(zāi)指數(shù)＝受災(zāi)面積/播種面積（旱災(zāi)指數(shù)、水災(zāi)指數(shù)、風災(zāi)指數(shù)、雹災(zāi)指數(shù)、霜凍災(zāi)指數(shù)、病蟲災(zāi)指數(shù)）2基于隨機變量(受災(zāi)指數(shù))的直方圖頻率分布作為經(jīng)驗分布代替災(zāi)害的概率分布(慶陽縣、鎮(zhèn)原縣、合水縣、寧縣、正寧縣、華池縣、環(huán)縣)3對于西峰市采用基于信息擴散理論的小樣本風險分析方法（李維德，蘭州大學(xué)博士論文，2004）結(jié)果及分析

1流域內(nèi)不同縣域自然災(zāi)害分析西峰市自然災(zāi)害圖00.10.20.30.40.50.60.70.80.91986199119962001旱災(zāi)水災(zāi)風災(zāi)雹災(zāi)霜凍災(zāi)病蟲災(zāi)慶陽縣自然災(zāi)害圖00.10.20.30.40.50.60.70.8195019701990旱災(zāi)水災(zāi)風災(zāi)雹災(zāi)霜凍災(zāi)病蟲災(zāi)鎮(zhèn)原縣自然災(zāi)害圖00.10.20.30.40.50.60.70.8195019601970198019902000旱災(zāi)水災(zāi)風災(zāi)雹災(zāi)霜凍災(zāi)病蟲災(zāi)正寧縣自然災(zāi)害圖00.10.20.30.40.50.60.70.8195019601970198019902000旱災(zāi)水災(zāi)風災(zāi)雹災(zāi)霜凍災(zāi)蟲災(zāi)合水縣自然災(zāi)害圖00.10.20.30.40.50.60.70.8195019601970198019902000旱災(zāi)水災(zāi)風災(zāi)雹災(zāi)霜凍災(zāi)病蟲災(zāi)華池縣自然災(zāi)害圖00.10.20.30.40.50.60.70.8195019601970198019902000旱災(zāi)水災(zāi)風災(zāi)雹災(zāi)霜凍災(zāi)病蟲災(zāi)環(huán)縣自然災(zāi)害圖00.10.20.30.40.50.60.70.80.9195019601970198019902000旱災(zāi)水災(zāi)風災(zāi)雹災(zāi)霜凍災(zāi)病蟲災(zāi)寧縣自然災(zāi)害圖00.20.40.60.81195019601970198019902000旱災(zāi)水災(zāi)風災(zāi)雹災(zāi)霜凍災(zāi)病蟲災(zāi)慶陽地區(qū)旱災(zāi)分布圖00.20.40.60.81195019601970198019902000慶陽西峰鎮(zhèn)原寧縣正寧合水華池環(huán)縣2單因素自然災(zāi)害生態(tài)風險分析

鎮(zhèn)原縣風險指數(shù)：受災(zāi)指數(shù)的大小。風險估計值：表示大于該風險指數(shù)的概率旱災(zāi)風險指數(shù)5.0010.0015.0020.0025.0030.0035.0040.0045.0050.0055.0060.0070.00旱災(zāi)風險估計值0.700.560.480.440.380.320.280.200.180.100.060.040.02雹災(zāi)風險指數(shù)1.002.003.004.005.0010.0020.00雹災(zāi)估計值0.710.630.490.450.370.080.02霜凍災(zāi)風險指數(shù)1.002.003.004.005.0010.0020.00霜凍災(zāi)風險估計值0.630.530.430.390.290.140.042單因素自然災(zāi)害生態(tài)風險分析

慶陽縣旱災(zāi)風險指數(shù)5.0010.0015.0020.0025.0030.0035.0040.0045.0050.0055.0060.0065.00旱災(zāi)風險估計值0.680.600.560.500.440.380.320.260.220.200.180.120.02雹災(zāi)風險指數(shù)1.002.003.004.005.0010.00雹災(zāi)估計值0.520.360.240.200.120.04霜凍災(zāi)風險指數(shù)1.002.003.004.005.0010.0015.0020.00霜凍災(zāi)風險估計值0.520.460.320.300.260.100.040.022單因素自然災(zāi)害生態(tài)風險分析

環(huán)縣旱災(zāi)風險指數(shù)51015202530.0035.0040.0045.0050.0055.0060.0070.0080.00旱災(zāi)風險估計值0.860.730.590.550.450.430.410.330.240.160.120.080.040.02雹災(zāi)風險指數(shù)1.002.003.004.005.0010.00雹災(zāi)估計值0.650.510.470.370.240.16霜凍災(zāi)風險指數(shù)1.002.003.004.005.0010.0020.0040.00霜凍災(zāi)風險估計值0.650.530.350.310.330.120.060.022單因素自然災(zāi)害生態(tài)風險分析

華池旱災(zāi)風險指數(shù)5.0010.0015.0020.0025.0030.0035.0040.0045.0050.0055.00旱災(zāi)風險估計值0.650.530.470.370.310.270.220.200.160.080.02雹災(zāi)風險指數(shù)1.002.003.004.005.0010.00雹災(zāi)估計值0.650.510.470.270.240.10霜凍災(zāi)風險指數(shù)1.002.003.004.005.0010.0020.0030.00霜凍災(zāi)風險估計值0.630.550.470.390.330.100.060.022單因素自然災(zāi)害生態(tài)風險分析

合水旱災(zāi)風險指數(shù)5.0010.0015.0020.0025.0030.0035.0040.0045.0050.0055.0060.0065.0070.00旱災(zāi)風險估計值0.630.550.510.430.350.290.270.250.240.220.180.160.140.08雹災(zāi)風險指數(shù)1.002.003.004.005.0010.00雹災(zāi)估計值0.450.350.290.160.120.02霜凍災(zāi)風險指數(shù)1.002.003.004.005.0010.0020.0030.00霜凍災(zāi)風險估計值0.610.550.450.310.290.100.060.042單因素自然災(zāi)害生態(tài)風險分析

正寧旱災(zāi)風險指數(shù)5.0010.0015.0020.0025.0030.0035.0040.0045.0050.0055.0060.0065.00旱災(zāi)風險估計值0.710.530.410.370.290.250.180.160.140.080.060.040.02雹災(zāi)風險指數(shù)1.002.003.004.005.0010.0020.0025.00雹災(zāi)估計值0.490.310.270.250.120.04霜凍災(zāi)風險指數(shù)1.002.003.004.005.0010.0020.0030.00霜凍災(zāi)風險估計值0.570.480.370.330.290.140.022單因素自然災(zāi)害生態(tài)風險分析

寧縣旱災(zāi)風險指數(shù)5.0010.0015.0020.0025.0030.0035.0040.0045.0050.0055.0060.0065.0080.0090.00旱災(zāi)風險估計值0.590.530.470.390.350.270.250.200.180.160.140.100.060.040.02雹災(zāi)風險指數(shù)1.002.003.004.005.0010.0020.0025.00雹災(zāi)估計值0.550.350.240.180.14霜凍災(zāi)風險指數(shù)1.002.003.004.005.0010.0020.0030.00霜凍災(zāi)風險估計值0.510.430.390.350.310.180.060.042單因素自然災(zāi)害生態(tài)風險分析

西峰市旱災(zāi)風險指數(shù)5.0010.0015.0020.0025.0030.0035.0040.0045.0050.0055.0060.0065.00旱災(zāi)風險估計值0.670.620.560.540.390.380.350.260.210.200.150.090.01雹災(zāi)風險指數(shù)1.002.003.004.005.0010.00雹災(zāi)估計值0.540.390.260.190.110.03霜凍災(zāi)風險指數(shù)1.002.003.004.005.0010.0015.0020.00霜凍災(zāi)風險估計值0.560.450.330.290.280.130.050.033不同旱害風險指數(shù)空間分布比較旱災(zāi)風險指數(shù)為5％、10％、15％時不同地區(qū)的旱災(zāi)風險估計值3不同旱害風險指數(shù)空間分布比較雹災(zāi)風險指數(shù)為5％、10％、15％時不同地區(qū)的雹災(zāi)風險估計值3不同旱害風險指數(shù)空間分布比較