Subjects: Geosciences >> Geography submitted time 2024-03-01 Cooperative journals: 《干旱区研究》
Abstract： The construction of mathematical models is one of the important methods to estimate shrub biomass. In this study, two desert shrubs, Reaumuria soongarica and Sympegma regelii, commonly found in the piedmont belt of the northern slopes of the mid Kunlun Mountains, were observed in this study. The whole-plant harvesting method was used, plant height (H), canopy area (S) and plant volume (V) were used as the independent variables, and plant above-ground biomass (W1), below-ground biomass (W2) and whole-plant biomass (W3) were used as the dependent variables, to establish function model. The optimal models for biomass estimation of these two desert shrubs were selected based on the largest determination coefficient (R2), the smallest estimated standard deviation (SEE) and significant level (P<0.001). The results showed that the optimal models for biomass estimation of R. soongarica and S. regelii were quadratic function model, except for the whole plant optimal prediction model of S. regelii was linear function model. For R. soongarica, the highest correlation was observed between plant volume (V) and biomass, with R2 ranged from 0.820 to 0.920. For S. regelii, the highest correlation between canopy area (S) and biomass was observed, with R2 ranged from 0.935 to 0.973. The optimal models for biomass estimation of R. soongarica and S. regelii all passed through significance test (P<0.001), with fit rates ranging from 84.1% to 95.6%, and these models could be used for biomass estimation. The results from this study will be very helpful for studying carbon stocks and evaluating carbon sink potential in desert ecosystem.
Subjects: Geosciences >> Geography submitted time 2022-04-13 Cooperative journals: 《干旱区地理》
Abstract：荒漠化是当今最为严重的生态问题之一，开展荒漠化风险量化评估，有助于荒漠化风险调控，实现区域生态经济可持续发展。通过从气候、下垫面和社会经济等因素选取指标，构建吐鲁番市荒漠化风险评价体系，基于3S技术分析评估其20002018年的荒漠化风险程度，并采用地理探测器进行驱动力分析。结果表明：（1）20002018年吐鲁番市荒漠化风险变化较大，总体呈现出局部变差整体向好的趋势，东部荒漠化风险程度高于西部地区。（2）研究时段内吐鲁番市东部鄯善县的极高风险面积增加；西部托克逊县的极高风险范围得到控制，面积明显缩小；中部高昌区极低风 险面积减少，低度风险分布较为稳定。（3）单因子驱动力：起沙风天数、第一产业GDP、降水量、生境质量指数、牲畜数量、平均气温6个因子对吐鲁番市荒漠化风险影响较大；在两两指标交互作用中，起沙风天数与第一产业GDP、降水量、生境质量指数、平均气温、牲畜数量的相互耦合是影响荒漠化风险的主要因素。
Subjects: Geosciences >> Geography submitted time 2022-01-26 Cooperative journals: 《干旱区研究》
Abstract：生态脆弱性评价是了解区域生态状况的重要途径，科学评估生态脆弱性等级及变化对区域生态保护与建设，实现区域可持续发展具有重要意义。研究利用SRP模型构建新疆生态脆弱性评价指标体系，结合空间主成分分析方法构建生态脆弱性指数评价模型，分析新疆生态脆弱性时空演变特征。结果表明：（1）20002018年，新疆生态敏感性整体为中度敏感，呈现东南高西北低，主要受景观破碎度和土壤侵蚀程度影响；生态恢复力受植被覆盖度影响较大，整体呈西北高、东南低，变化幅度小，恢复力较弱；生态压力大致呈南、北部的山区和中部绿洲区、山区高、东南低，主要影响因子是人均GDP、农业依赖度和人口密度。（2）20002018年新疆生态脆弱性整体处于中度脆弱到重度脆弱。南、北部植被覆盖度低的地区生态脆弱等级较高，中部高海拔林草丰富地区生态脆弱性等级相对较低；20002018年新疆生态脆弱性综合指数呈现先增长后降低趋势。（3）生态脆弱性主要驱动力方面，人为活动因子的农业依赖度、人口密度、土地垦殖率，自然环境因子的生境质量指数、景观破碎度、景观恢复力指数和年均降水量7个指标是新疆20002018年生态脆弱性变化的主要单因子；生境质量指数、景观恢复力指数、景观破碎度指数、植被覆盖率的变化与区域人类活动的相互作用是促使新疆生态脆弱性的主要驱动力。
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