岷江上游羌族聚落区土地利用对土壤碳库的影响

发布时间：2018-06-17 08:05

本文选题：土地利用 + GIS　；参考：《西南科技大学》2017年硕士论文

【摘要】：土地利用变化是影响土壤碳库动态的重要因素。本研究选择岷江上游理县2个相邻的羌族聚落——佳山村和九子村,分别位于干旱河谷的阴坡和阳坡,基于3S技术,分析1999～2014年研究区土地利用空间分布格局,利用野外采样分析不同土地利用类型(玉米、林地、草地、车厘子、李子、苹果、核桃、花椒)的土壤有机碳和全氮含量,研究传统作物转变为不同果园地对土壤有机碳库变化的影响,为评估岷江上游的生态服务价值提供科学依据。主要结果和结论包括:(1)1999～2014年羌族聚落土地利用变化显著。佳山聚落总面积为573.90 hm2,1999～2014年耕地减少188.17 hm2,而果园地增加95.03 hm2,林地增加147.50 hm2;九子聚落总面积267.20 hm2,1999～2014年耕地减少100.27 hm2,果园地增加65.40 hm2,林地增加14.95 hm2。羌族聚落土地利用正处于快速调整阶段,传统耕地(以种植玉米、蔬菜为主)大幅度转变为林地(洋槐)和果园地(种植车厘子、李子、苹果等),这种土地利用变化主要是退耕还林政策、比较利益和聚落人口空心化共同驱动作用的结果。(2)不同土地利用土壤有机碳差异明显,阴坡和阳坡同种土地利用土壤有机碳有一定差异,但大小关系不完全相同。佳山不同土地利用类型的土壤有机碳浓度为:车厘子(19.65 g·kg-1)林地(16.77 g·kg-1)苹果(15.77 g·kg-1)李子(15.42 g·kg-1)玉米(11.07 g·kg-1)草地(10.84 g·kg-1);九子不同土地利用土壤有机碳浓度为:车厘子(18.50 g·kg-1)苹果(16.83 g·kg-1)核桃(14.87 g·kg-1)李子(14.3 1 g·kg-1)林地(12.52 g·kg-1)玉米(11.57 g·kg-1)花椒(10.71 g·kg-1)草地(10.47 g·kg-1)。结果表明果园地土壤有机碳浓度明显高于传统耕地,主要归因于种植车厘子、李子和苹果等需要多施用有机肥,而种植玉米等以施用化肥为主。(3)阳坡不同土地利用土壤剖面(0～60 cm)有机碳累积强于阴坡。佳山不同土地利用土壤有机碳密度为:车厘子(9.32 kg m-2)林地(7.91 kg·m-2)苹果(7.48 kg·m-2)李子(6.59 kg·m-2)草地(5.16 kg· m-2)玉米(4.47 kg· m-2);九子不同土地利用土壤有机碳密度为:车厘子(10.78 kg · m-2)核桃(9.81 kg · m-2)苹果(9.01 kg · m-2)李子(8.76 kg·m-2)草地(7.74 kg·m-2)林地(7.33 kg· m-2)玉米(5.3 6 kg· m-2)花椒(4.91 kg · m-2)。这些结果表明种植车厘子、林地(洋槐)、核桃、苹果和李子较有利于土壤有机碳累积,而种植花椒不利于有机碳累积。(4)基于1999～2014年土地利用变化格局和不同土地利用土壤有机碳密度,1999～2014年佳山土壤有机碳储量增加7012.56 t,九子土壤有机碳储量增加2985.97 t,主要原因在于1999～2014年羌族聚落大力发展生态果业和退耕还林,将耕地、草地转变成车厘子、李子、苹果等果园地和洋槐生态林。可见,种植类型转变明显增大了土壤有机碳储量,有效提升了该区的生态服务价值。
[Abstract]:Land use change is an important factor affecting soil carbon pool dynamics. In this study, two adjacent Qiang settlements in Lixian County, Upper Minjiang River, Jiashan Village and Jiuzi Village, located on the shady and sunny slopes of the arid valley, were selected to analyze the spatial distribution pattern of land use in the study area from 1999 to 2014 based on 3s technology. Soil organic carbon (SOC) and total nitrogen (TN) contents of different land use types (maize, woodland, grassland, Cherry, plum, apple, walnut, prickly ash) were analyzed by field sampling. In order to evaluate the ecological service value of the upper reaches of Minjiang River, the effects of the transformation of traditional crops into different orchards on soil organic carbon pool were studied. The main results and conclusions include the significant land use change of Qiang settlement from 1999 to 2014. The total area of settlement in Jiashan from 1999 to 2014 decreased by 188.17 hm2, while the total area of the orchard increased by 95.03 hm2and the total area of forest increased by 147.50 hm2.The total area of the settlement of Jiaozi decreased by 100.27 hm2 from 1999 to 2014, increased by 65.40hm2in orchard, and increased by 14.95hm2.The total area of Jiushan settlement decreased by 100.27 hm2from 1999 to 2014, and the forest land increased by 14.95hm2. The land use of Qiang settlements is in the stage of rapid adjustment. The traditional cultivated land (mainly corn and vegetables) has been transformed into woodland (Robinia pseudoacacia) and orchards (planting Cherie, plum, etc.). This land use change is mainly a result of the policy of returning farmland to forest, which is the result of the combined driving effect of comparative benefits and the hollowing of settlement population. (2) the difference of soil organic carbon among different land uses is obvious. There are some differences in the use of soil organic carbon between the shady slope and the sunny slope, but the relationship is not exactly the same. The soil organic carbon concentrations of different land use types in Jiashan were 16.77 g kg-1 of Cegliezitii (19.65 g kg-1) forest land) 15.77 g kg-1 of apple and 15.42 g kg-1 of plums (11.07 g kg-1 of maize), and 10.84 g kg-1 of soil organic carbon of different land use in Jiaozi: 18.50 g kg-1 of Cegliezi (18.50 g kg-1) of apple and 16.83 g of apple. G. kg-1) walnut (14.87 g kg-1) plums (14.31 g kg-1) woodland (12.52 g kg-1) Corn (11.57 g kg-1) Zanthoxylum bungeanum 10.71 g kg-1) Grass (10.47 g kg-1). The results showed that the soil organic carbon concentration in the orchard was significantly higher than that in the traditional cultivated land, which was mainly attributed to the need to apply organic fertilizer more often, such as plums, plums and apples, etc. The accumulation of organic carbon in different land use soil profile of sunny slope was stronger than that in shady slope. The soil organic carbon density of different land use in Jiashan is 7.91 kg m ~ (-2) (P < 0.05), the soil organic carbon density of different land use is 7.91 kg ~ (m ~ (-2) and the density of soil organic carbon in different land use is 7.91 kg ~ (-2) (6.59 kg ~ (-2) m ~ (-2) of Plum (6.59 kg 路m ~ (-2) Maize (4.47 kg m ~ (-2), and the density of soil organic carbon in different land use is 10.78 kg m ~ (-2) in Jiushan. Peach is 9.81 kg m ~ (-2) apple is 9.01 kg m ~ (-2) plum is 8.76 kg m ~ (-2) grassland is 7.74 kg m ~ (-2) forest land is 7.33 kg m ~ (-2) corn is 5.36 kg m ~ (-2) Zanthoxylum bungeanum is 4.91 kg m ~ (-2). These results suggest that planting Che Kuo and woodland (Robinia pseudoacacia, walnut, apple and plum) is better for soil organic carbon accumulation. Planting Zanthoxylum bungeanum L. is not good for the accumulation of organic carbon.) based on the land use change pattern from 1999 to 2014 and the soil organic carbon density of different land use, the soil organic carbon storage of Jiashan Mountain from 1999 to 2014 increased by 7012.56 tons, and the soil organic carbon storage of Jiu sub-soil increased by 7012.56 tons. 2985.97 t, the main reason is that the Qiang settlement from 1999 to 2014 vigorously developed ecological fruit industry and returned farmland to forest. Transform cultivated land and grassland into Cherie, plum, apple and other orchards and locust ecological forest. Therefore, the change of planting type obviously increased the soil organic carbon storage and effectively promoted the ecological service value of the area.
【学位授予单位】：西南科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S153.6;F301.24

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