| 摘要: |
| 【目的】对西北针茅（Stipa krylovii）生育期的温度、降水、日照、积温、地温等气象要素进行综合分析，评价各气象要素对牧草产量的影响。【方法】以西北针茅牧草生育期间的逐日气象资料和草原全部牧草的产量为基础资料，运用积分回归的差分形式，计算了影响西北针茅产量的旬平均气温、≥0 ℃积温、5 cm地温、10 cm地温、降水量和日照时数等气象要素的影响系数，构建了影响西北针茅产量的气象要素评价模型，并进一步计算了产量影响指数，用于衡量西北针茅生育期各气候因子对最终产量的影响。【结果】各气象因素中，对高寒草地西北针茅牧草产量影响最大的是降水量,6月中旬、7月上旬和8月中旬降水量对牧草产量的影响指数达1 150.73～1 470.66 kg/hm2，5月中旬至6月上旬、6月下旬、7月中旬至8月上旬降水量对牧草产量的影响指数为491.72～819.01 kg/hm2；其次是日照时数，4月上中旬、5月中下旬、8月各旬日照时数对牧草产量的影响指数为347.90～668.17 kg/hm2；第3是≥0 ℃积温，4月中旬至6月上旬、8月下旬≥0 ℃积温对牧草产量的影响指数达207.32～486.40 kg/hm2；第4是旬平均气温，4月中下旬和7月中旬的旬平均气温可以造成146.22～173.76 kg/hm2的产量波动；第5是地温，5月中旬至6月中旬，5和10 cm地温对牧草产量的影响指数分别为42.46～62.55 kg/hm2和41.46～51.63kg/hm2。【结论】降水量对高寒草地西北针茅产量的影响最大，其次是日照时数，第3是≥0 ℃积温，第4是旬平均气温，5和10 cm地温对西北针茅产量影响较小。 |
| 关键词: 西北针茅 气象要素 积分回归 产草量 影响指数 |
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| 基金项目:青海省科技厅科技促进新农村建设计划项目(2009-N-503) |
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| Effects of climates on primary production of alpine Stipa krylovii grassland |
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| Abstract: |
| 【Objective】 In alpine grassland of Qinghai,Stipa krylovii is a dominant species and important forage.This study aims to disclose relationships between primary production of S.krylovii grassland and climatic factors such as temperature,precipitation,light time,accumulated temperature above 0 ℃,and ground temperature.【Method】 Based on everyday records of the climatic factors and primary production of S.krylovii grassland in growth period,a model is established to evaluate effects of these factors on primary production of S.krylovii grassland.【Result】1) Precipitation is the first important factor.In middle June,early July and middle August,it affects the production by 1 150.73-1 470.66 kg/hm2;in middle May,late May,early June,late June,middle July,late July,early August and middle August,it does by 491.72-819.01 kg/hm2.2) Light time is the second factor.In early April,middle April,middle May,late May,August,it affects the production by 347.90-668.17 kg/hm2.3) Accumulated temperature is the third factor.From middle April to early June,and in late August,it affects the production by 207.32-486.40 kg/hm2.4) Average air temperature of 10 days is the fourth factor.In late April,middle July and middle April,it affects the production by 146.22-173.76 kg/hm2.5) Ground temperature of 10 days is the 5th factor.Mid-May to mid-June,5 and 10 cm ground temperatures to grass crop’s influence index respectively are 42.46-62.55 kg/hm2 and 41.46-51.63 kg/hm2.【Conclusion】 Precipitation is the strongest factor to affect primary production of S.krylovii grassland,light time the second,accumulated temperature the third,average temperature of 10 days the fourth,5 and 10 cm grand temperature the weakest. |
| Key words: Stipa krylovii meteorological element integral regression grass yield effect index |
