维持城市生态系统服务供需平衡是建设宜居城市、提高城市居民福祉的基础,同时对区域经济与可持续发展具有重要意义。以西安市建成区为例,基于2018年遥感数据、统计数据和实地调研等多源数据,构建粮食需求、水资源需求、固碳释氧、空气...维持城市生态系统服务供需平衡是建设宜居城市、提高城市居民福祉的基础,同时对区域经济与可持续发展具有重要意义。以西安市建成区为例,基于2018年遥感数据、统计数据和实地调研等多源数据,构建粮食需求、水资源需求、固碳释氧、空气净化、高温调节、减弱噪声和休闲娱乐服务需求测算模型,并应用ArcGIS等分析工具,对研究区城市绿色基础设施(Urban green infrastructure,UGI)服务供需空间匹配关系进行评估和分析,最后运用最小累积阻力模型识别生态源地和生态廊道,对西安市UGI空间格局进行优化。结果表明:(1)西安市建成区UGI分布不均匀,破碎化程度高,连通性较差。UGI提供的生态系统服务总价值小于居民对服务需求总价值,在空间上表现为显著不匹配性。(2)不同生态系统服务供需匹配状况存在差异,高温调节服务、空气净化服务和休闲娱乐服务供大于求,匹配状况较好;粮食供给、固碳释氧、水源涵养和减弱噪声服务供小于求,供需赤字。(3)研究区生态系统服务供需具有显著空间异质性,随着人口集聚程度的提高,大部分生态系统服务(如高温调节、减弱噪声等)供需的空间匹配程度显著下降,在空间上表现为由城市中心的严重失调向边缘的良好匹配渐变。(4)研究区生态源地斑块面积较小,破碎化程度高,连接度低,UGI网络缺乏主干生态廊道。通过构建由沿渭河、秦岭北麓2个生态走廊,沣河、潏河、灞河等7个生态保育区及沿道路绿化带等组成的UGI网络,可使生态系统服务供需空间关系更趋协调。展开更多
The excessive expansion of urbanized areas has resulted in haphazard land utili- zation, immoderate consumption of superior agricultural land and water resources, significant fragmentation of agricultural landscape, a...The excessive expansion of urbanized areas has resulted in haphazard land utili- zation, immoderate consumption of superior agricultural land and water resources, significant fragmentation of agricultural landscape, and gradual deterioration of the agro-ecological en- vironment. Combined, these factors cause poor land use efficiency. Under these circum- stances, comprehensively assessing land use efficiency for urban agriculture is a key issue in land use research. Currently, evaluation methods for agricultural land use efficiency narrowly concentrate on aspects of economic input and output. However, urban agro-ecosystems can provide diverse economic, social, and ecological services and functions. In particular, the social and ecological services and functions originating from agricultural land, which have a higher value than economic services, play a significant role in ensuring regional social, eco- logical, and environmental security. However, recent research has rarely taken these benefits into consideration. Therefore, land use value has been greatly underestimated, which has resulted in mishandled and poor land use policies. In this study, we apply Landsat imagery and social and economic statistical data for the Xi＇an metropolitan zone （XMZ） to investigate agricultural multi-functionality. We develop an evaluation framework for urban agricultural land use efficiency and identify agro-ecosystem services and functions as important outputs from agricultural land. The land use efficiency of urban agriculture is then evaluated using ecosystem services models, providing a mechanism for assessing spatial-temporal changes in land use efficiency in the XMZ from 1999 to 2015. Four important conclusions are reached from this analysis. First, the rapid urbanization and agricultural transformation from traditional cereal cultivation to modern urban agriculture has resulted in steadily increasing costs, out- puts, and land use efficiency of urban agriculture. The total output value increased 41% and land use efficiency per hectare increased by 33.13% on average. Second, the spatial patterns of comprehensive output and land use efficiency were dominated by economic outputs from agricultural land. Areas near cities, which are dominated by orchard and arable land, provide more economic functions. These areas support and regulate services due to the transforma- tion from extensive cereal production to intensive modern urban agriculture; therefore, they have higher output value and land use efficiency. In contrast, areas distant from cities, towns, and high traffic roads, namely, remote rural areas, provide more support and regulating ser- vices, but have relatively lower economic function due to inaccessibility tO urban markets and slow agricultural transformation. Therefore, these areas have lower output value and land use efficiency. The spatial change in agricultural output and land use efficiency in urban areas is strongly dependent on the degree of urbanization and agricultural transformation. Third, the total output value and land use efficiency of urban agriculture measured with our approach are much higher than evaluations using traditional methods. However, the spatial patterns measured using the two approaches are in agreement. The evaluation framework integrates ecological services and economic and social functions into a comprehensive output from agricultural land. This approach is more methodical and accurate for evaluating the compre- hensive efficiency of land use based on quantities and spatial scale because they are at the pixel scale. Finally, the evaluation results have important implications for enhancing current agricultural subsidies and even implementing ecological payment policies in China. Most importantly, they can be directly applied to agricultural transformation regulations, decision-making, and guidance for rational land utilization.展开更多
文摘维持城市生态系统服务供需平衡是建设宜居城市、提高城市居民福祉的基础,同时对区域经济与可持续发展具有重要意义。以西安市建成区为例,基于2018年遥感数据、统计数据和实地调研等多源数据,构建粮食需求、水资源需求、固碳释氧、空气净化、高温调节、减弱噪声和休闲娱乐服务需求测算模型,并应用ArcGIS等分析工具,对研究区城市绿色基础设施(Urban green infrastructure,UGI)服务供需空间匹配关系进行评估和分析,最后运用最小累积阻力模型识别生态源地和生态廊道,对西安市UGI空间格局进行优化。结果表明:(1)西安市建成区UGI分布不均匀,破碎化程度高,连通性较差。UGI提供的生态系统服务总价值小于居民对服务需求总价值,在空间上表现为显著不匹配性。(2)不同生态系统服务供需匹配状况存在差异,高温调节服务、空气净化服务和休闲娱乐服务供大于求,匹配状况较好;粮食供给、固碳释氧、水源涵养和减弱噪声服务供小于求,供需赤字。(3)研究区生态系统服务供需具有显著空间异质性,随着人口集聚程度的提高,大部分生态系统服务(如高温调节、减弱噪声等)供需的空间匹配程度显著下降,在空间上表现为由城市中心的严重失调向边缘的良好匹配渐变。(4)研究区生态源地斑块面积较小,破碎化程度高,连接度低,UGI网络缺乏主干生态廊道。通过构建由沿渭河、秦岭北麓2个生态走廊,沣河、潏河、灞河等7个生态保育区及沿道路绿化带等组成的UGI网络,可使生态系统服务供需空间关系更趋协调。
基金National Natural Science Foundation of China, No.41271550 Humanities and Social Sciences Project of Ministry of Education in the West and the Frontier Areas, No. 12XJC790003
文摘The excessive expansion of urbanized areas has resulted in haphazard land utili- zation, immoderate consumption of superior agricultural land and water resources, significant fragmentation of agricultural landscape, and gradual deterioration of the agro-ecological en- vironment. Combined, these factors cause poor land use efficiency. Under these circum- stances, comprehensively assessing land use efficiency for urban agriculture is a key issue in land use research. Currently, evaluation methods for agricultural land use efficiency narrowly concentrate on aspects of economic input and output. However, urban agro-ecosystems can provide diverse economic, social, and ecological services and functions. In particular, the social and ecological services and functions originating from agricultural land, which have a higher value than economic services, play a significant role in ensuring regional social, eco- logical, and environmental security. However, recent research has rarely taken these benefits into consideration. Therefore, land use value has been greatly underestimated, which has resulted in mishandled and poor land use policies. In this study, we apply Landsat imagery and social and economic statistical data for the Xi＇an metropolitan zone （XMZ） to investigate agricultural multi-functionality. We develop an evaluation framework for urban agricultural land use efficiency and identify agro-ecosystem services and functions as important outputs from agricultural land. The land use efficiency of urban agriculture is then evaluated using ecosystem services models, providing a mechanism for assessing spatial-temporal changes in land use efficiency in the XMZ from 1999 to 2015. Four important conclusions are reached from this analysis. First, the rapid urbanization and agricultural transformation from traditional cereal cultivation to modern urban agriculture has resulted in steadily increasing costs, out- puts, and land use efficiency of urban agriculture. The total output value increased 41% and land use efficiency per hectare increased by 33.13% on average. Second, the spatial patterns of comprehensive output and land use efficiency were dominated by economic outputs from agricultural land. Areas near cities, which are dominated by orchard and arable land, provide more economic functions. These areas support and regulate services due to the transforma- tion from extensive cereal production to intensive modern urban agriculture; therefore, they have higher output value and land use efficiency. In contrast, areas distant from cities, towns, and high traffic roads, namely, remote rural areas, provide more support and regulating ser- vices, but have relatively lower economic function due to inaccessibility tO urban markets and slow agricultural transformation. Therefore, these areas have lower output value and land use efficiency. The spatial change in agricultural output and land use efficiency in urban areas is strongly dependent on the degree of urbanization and agricultural transformation. Third, the total output value and land use efficiency of urban agriculture measured with our approach are much higher than evaluations using traditional methods. However, the spatial patterns measured using the two approaches are in agreement. The evaluation framework integrates ecological services and economic and social functions into a comprehensive output from agricultural land. This approach is more methodical and accurate for evaluating the compre- hensive efficiency of land use based on quantities and spatial scale because they are at the pixel scale. Finally, the evaluation results have important implications for enhancing current agricultural subsidies and even implementing ecological payment policies in China. Most importantly, they can be directly applied to agricultural transformation regulations, decision-making, and guidance for rational land utilization.
