KMS XINJIANG INSTITUTE OF ECOLOGY AND GEOGRAPHY，CAS
| 干旱区绿洲农田防护林景观格局及其对作物产量的影响 | |
| 杨书雅 | |
| Subtype | 硕士 |
| Thesis Advisor | 李小玉 |
| 2017-05-01 | |
| Degree Grantor | 中国科学院大学 |
| Place of Conferral | 新疆乌鲁木齐 |
| Degree Discipline | 工程硕士 |
| Keyword | 绿洲 农田防护林 景观格局 防护水平 棉花产量 oasis farmland windbreaks landscape pattern protection level cotton yield |
| Abstract | The windbreak is an agroforestry ecological system integrating economy, ecology andsociety. It plays a key role in reducing the wind speed, improving the microclimate and soilconditions of agricultural and animal husbandry production, maintaining the health offarmland ecosystem, ensuring the stable yield of agriculture and animal husbandry, andrealizing the sustainable development of farmland ecosystem. However, farmlandwindbreaks also have negative effects on crop yield. The evaluation of the protective effectof farmland windbreak is the key to test the rational construction of the windbreak and thescientific planning and design of the future windbreak. It is the link between theconstruction and management of the windbreak. What is the comprehensive benefit of thewindbreak? Does it help to achieve the goal of planning and design? It is the urgent need toanswer the question of windbreak effect. Therefore, this study selects the oasis in theManas River Basin which is a strong representative and typical in the arid area of Xinjiangand uses the remote sensing data and statistical data to carry out the evaluation of theprotective effect of the oasis farmland windbreak in the basin. The landscape pattern offarmland windbreaks in arid oasis and its effect on the main crop yield in the study area arealso studied. The following results were obtained:(1) The analysis of the landscape pattern with the ratio of belt to patch, theconnectivity and the ring degree to the windbreak of Manas County, Shawan County andthe Regimental Farm showed that the relative error of each landscape metric was greaterthan 0.15. The prominent problems include the limited windbreak area, uneven windbreakdistribution, small number of closed grids and poor forming conditions. In order to achievethe sustainability of the farmlands, the missing windbreak needs to be developed and thedensity of windbreak should also be increased.(2) Based on the Landsat8 OLI remote sensing image as the data source and the dataof the cotton space extracted by the object-oriented method, and the light energy utilizationmodel, the CASA model, and the crop biomass-yield model was used to analyze the yield of the main crop. Cotton production was estimated using the data released by the Bureau ofStatistics of the county cotton yield data to verify. The cotton acreage of the Manas RiverBasin accounts for 61.13% of the total area of crop cultivation, and the average yield ofcotton in the basin is 2049.27kg/ha, and the estimation error is less than 4%. It can be seenthat the high yield area of cotton higher than 2400kg/ha is mainly distributed in the centralarea of the oasis in Manas County, Farm 143, Farm 121 and Farm 122. The cotton yield is1800~2400kg/ha. The middle-yielding areas of cotton are mainly distributed in ShawanCounty and Oasis East and West. The low yield area of cotton yield below 1800kg/ha ismainly distributed in Xinhu Farm, Farm 136 West, Farm 135 and other southern edge aswell as near desert areas.(3) Based on the multi-period Landsat series of image data, the spatial distributioninformation of windbreak in different age groups was extracted. The quality coefficient ofwindbreaks was calculated by the normalized vegetation index of the windbreaks.Windbreak evaluation system was established to analyze the effect of different protectionlevels on cotton yield according to the tree height and the maximum protection distance ofdifferent age groups. The results showed that the cotton yield was in a stable state when theprotection level of Manas County and Shawan County was 70%. Compared with theprotection level of 0%, the cotton yield increased by 136 kg/ha and 175 kg/ha. When theprotection level of Regimental Farm is 90%, the cotton yield is in a basically stable state.Compared with the protection level of 0%, the cotton yield increased by 214kg/ha.Compared to Manas County and Shawan County landscape pattern, the Regimental Farmcoverage and continuity is poor, showing that the construction of the windbreak in theRegimental Farm needs to be further strengthened and improved. |
| Other Abstract | 防护林是集经济、生态、社会三大效益为一体的农林复合生态体系，对于降低风速，改善农牧业生产的微气候及土壤条件，维持农田生态系统的健康，确保农牧业稳产高产，实现农田生态系统的可持续发展发挥着关键性的作用，但同时农田防护林对林带边缘作物产量也产生一定的负效应。农田防护林防护效应评价是检验防护林营建合理与否和未来防护林科学规划设计的关键，是联系防护林构建与经营的纽带。防护林构建后综合效益如何？是否达到规划设计的目标？是防护林效应评价中亟需回答的问题。因此，本研究选择在干旱区具有较强代表性和典型性的新疆天山北坡玛纳斯河流域绿洲为研究区，利用遥感数据及统计资料数据，开展流域内绿洲农田防护林的防护效应评价，分析干旱区绿洲农田防护林网的景观格局及其对研究区内主要作物产量的影响。得到如下研究结果：（1）通过对玛纳斯县、沙湾县和团场的防护林网带斑比、连接度和环度值等景观格局指标的分析表明，各景观指标的相对误差均大于 0.15，说明玛纳斯河流域绿洲农田防护林网尚且达不到优质标准，存在林带面积不足、林网分布不均匀、闭合网格较少，成型状况较差等问题，建议在防护林的建设和管理中，加强缺失林带的补齐工作，并增加林带密度，通过科学合理的防护林网空间配置实现绿洲农田的可持续发展。（2）以 Landsat8 OLI 遥感影像为数据源，在利用面向对象法提取棉花空间信息的基础上，基于光能利用率模型和 CASA 模型，通过作物生物量—产量模式对研究区最主要的作物类型棉花的产量进行了估算，利用统计局公布的县市棉花单产数据进行验证。玛纳斯河流域棉花种植面积占作物种植总面积的 61.13%，流域内棉花平均产量为 2049.27kg/ha，估算误差小于 4%。通过估算的棉花产量空间分布图可以看出，棉花单产高于 2400kg/ha 的高产区主要分布在玛纳斯县、143 团、121 团、122 团等绿洲中部区域；棉花单产为 1800~2400kg/ha 的中产区主要分布在沙湾县和绿洲东、西部的边缘团场；而棉花单产低于 1800kg/ha 的低产区主要分布在新湖农场、136 团西部、135 团等绿洲南部边缘以及临近荒漠区域。（3）基于多期 Landsat 系列影像数据，提取不同年龄组防护林的空间分布信息，通过防护林带的归一化植被指数计算防护林质量系数，结合不同年龄组的树高和最大防护距离，建立防护林评价体系，分析不同防护水平对棉花产量的影响。结果表明：玛纳斯县和沙湾县防护林防护水平为 70%时，棉花单产处于基本稳定状态，相较于防护水平为 0%时，棉花单产在两个县分别增加了 136kg/ha 和 175kg/ha；团场防护林防护水平为 90%时，棉花单产处于基本稳定状态，相较于防护水平为 0%时，棉花单产增加了 214kg/ha。兵团农场的防护林网景观格局和玛纳斯县及沙湾县的相比，其覆盖度和连续性较差表明，团场防护林建设还需进一步加强和完善。 |
| Subject Area | 测绘工程 |
| Language | 中文 |
| Document Type | 学位论文 |
| Identifier | http://ir.xjlas.org/handle/365004/14910 |
| Collection | 研究系统_荒漠环境研究室 |
| Affiliation | 中国科学院新疆生态与地理研究所 |
| First Author Affilication | 中国科学院新疆生态与地理研究所 |
| Recommended Citation GB/T 7714 | 杨书雅. 干旱区绿洲农田防护林景观格局及其对作物产量的影响[D]. 新疆乌鲁木齐. 中国科学院大学,2017. |
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