关于玛纳斯河灌区水价改革的几点思考

水是一种特殊商品,有使用价值。然而,福利供水和低水价以及水价改革的滞后,一方面掩盖了水的稀缺性、珍贵性;一方面水利工程无法得到资金补偿。以玛纳斯河灌区为对象,对此问题进行探讨,并提出了水价改革的基本思路。     

南京市观赏型草坪草主要病害发生的特点及防治

报道了南京市常见的草坪草病害如褐斑病、腐霉枯萎病、溶失病等主要症状及发生条件,并探索了草坪草病害防治的有效措施。     

郴州市农产品虚拟水的量化分析

为提供农业结构战略性调整和区域水资源管理的有效措施,以虚拟水计算方法为基础,对2000年湖南郴州市的农产品虚拟水进行了量化分析,并对区域农产品的战略性调整和区域水资源有效配置决策思路进行了探讨．结果表明,每生产1kg大米,需要耗费至少773．8kg的水资源;生产1kg植物油耗费的水量为8286．3kg;生产1kg蔬菜的水量最少,但至少也需要149．9kg的水量．郴州市的农村居民年农产品虚拟水数量远高于城镇居民的,其中大米所消费的虚拟水量就分别达到147．166m^3和41．744m^3．在不降低人均水资源消费需求和不降低人类生活质量的情况下,水资源较丰富的地区可通过农产品虚拟水贸易方式,更好地发挥区域性优势,主动开发和生产有效益的水资源密集型农产品;通过农产品虚拟水战略,在更大区域范围内,可以很好地缓解水资源紧缺地区的压力,并引导人们改变其消费结构和消费模式,创新水资源管理体制。     

重庆市森林资源现状及经营策略

地处我国东西结合部的重庆市,总面积823.7万hm2,属中亚热带湿润季风气候类型、亚热带常绿阔叶林区,植被类型丰富,森林覆盖率为27.15%,活立木总蓄积为1.2亿m3。其树种、林种、林龄结构不合理、林分质量低下。提出了今后应加强森林资源保护、积极培育森林、发展城市林业、调整林种树种结构,加快产业体系建设等方面的经营策略。     

Tree species-rich open oak woodlands within scattered urban landscapes promote biodiversity

It is becoming increasingly evident that cities are important places for biodiversity. Biodiverse urban forests are vital green areas within cities and have favorable impacts on the citizens, including their health. We focused on the effect of the urban forest environment on biodiversity in Prague, the capital of the Czech Republic. We used a multi-taxon approach with five taxa of different ecological demands: butterflies, bees and wasps, vascular plants, mosses, and lichens. We modeled their responses to the various urban forest attributes at four hierarchical levels – plot, permeability, forest, and landscape. Our results revealed that temporally continuous forests dominated by native oaks with open canopies, a high number of admixed and interspersed tree species and shrubs, together with scattered trees in the surrounding landscape, were optimal biodiverse forest environments. The most influential parameter that positively influenced bees and wasps, plants, and lichens at the plot level was canopy openness. We found that the permeability was suitable mainly on 20 m surroundings and increasing coverage of native oaks and tree species richness were the most important parameters. Continuity was the only found parameter that influenced mosses at the forest level. Scattered tree vegetation was the most important landscape parameter and positively drove the species richness of bees and wasps. Forest management methods can relatively easily solve the improvement of the scattered light gap structure within urban forests. Applying traditional forest management (pasture management, controlled burning and/or coppicing) is also an option but requires sensitive communication with the public. The canopy cover has been used as an indicator of urban forest health conditions, now indicating that artificial disturbances could be important issues for urban forest management and planning in the future. Therefore, active forest management is an essential method for biodiversity maintenance. We conclude that urban forests have a high potential for increasing native biodiversity. The response of the studied groups in urban forests was complementary. The resulting biodiverse stages of urban forests are akin to the established idea of the open temperate deciduous woodlands.     

Carbon sinks in urban public green spaces under carbon neutrality: A bibliometric analysis and systematic literature review

Urban green spaces play essential roles in regulating the global carbon cycle and reducing carbon dioxide (CO₂) emissions. However, research on the carbon sequestration efficiency of urban public green spaces, which is closely related to the human settlement environment, has not received enough attention. Thus, we systematically analyzed the existing literature in the Web of Science core database using bibliometrics and network analysis combined with the CiteSpace visualization tool. The aim of this review was to elucidate the focus and development trend of research conducted between 2007 and 2022 on carbon sinks in urban public green spaces. Our results demonstrated that: 1) Numbers of related publications are increasing annually, indicating that the subject is receiving increasing global attention. Related research topics primarily focus on two aspects: carbon sink measurement methods and sustainable carbon sink design for urban public green spaces. 2) Methods for measuring and monitoring carbon sinks in the urban public green spaces include sample plot measurement, the assimilation method, the micrometeorological method, the remote sensing (RS) estimation method, and laboratory work. Most methods follow the forestry system approach and lack the methods and techniques to directly assess the carbon sink effectiveness of urban public green spaces. 3) Key factors affecting the carbon sink capacity of urban public green spaces are: plant species selection, plant community structure, green space characteristics, and maintenance management. 4) Future research should focus on encouraging public participation in the design of sustainable carbon sinks in urban public green spaces, advancing biodiversity research on carbon sinks in urban public green spaces, and enhancing the precision of measurements while addressing regional differences. This study contributes to the integration of research on the effectiveness of carbon sinks in urban public green spaces and provides a theoretical reference and guidance reduces prospective urban emission and achieves climate goals.     

湘江衡阳段河漫滩沉积物粒度特征与历史洪水事件

[目的]分析河漫滩沉积记录的历史时期洪水信息,揭示极端洪水事件和洪水发生规律,为防洪减灾提供指导.[方法]根据湘江河漫滩沉积剖面91个样品的粒度分析,结合AMS 14C精确测年,分析湘江衡阳段河漫滩剖面粒度特征与洪水事件.[结果]①河漫滩沉积物粒度组成以粗粉砂、粗砂、极细砂为主.粒度参数显示,剖面洪水沉积动力较强,分选...     

Investigating the spatial distribution of urban parks from the perspective of equity-efficiency: Evidence from Chengdu,China

Urban parks play a crucial role in urban public green infrastructure, providing recreational places for urban residents while carrying values of aesthetics, ecology, humanities, economy, life, and society. However, achieving an equitable and efficient spatial layout of urban parks is a challenging task due to limited urban space resources, which requires further exploration. This study employed multisource big data and GIS technology to constructed an indicator system for evaluating the equity-efficiency of urban park spatial distribution. We examined the spatial distribution of 85 parks across 62 sub-districts in the main urban area of Chengdu, the largest city in western China and the first Park City of China. The results demonstrated that equity was polarized, with an indicator value ranging from 0 to 0.77 and an average value of 0.32. The sub-district of Sansheng had the highest equity, while Wenjia and Kanghe had the lowest equity. Twenty-one sub-districts had no parks, and the equity of park spatial distribution in these areas was low. The efficiency indicator ranged from 0.20 to 0.62, with an average value of 0.40. The efficiency of the main urban area was high in the southwest and low in the northeast. The sub-district of Huangtianba had the highest efficiency, while Jinguanyi had the lowest efficiency. In the two-dimensional quadrant of equity-efficiency, 24 sub-districts had high equity and high efficiency, 13 sub-districts had high equity and low efficiency, 4 sub-districts had low equity and high efficiency, and 21 sub-districts had low equity and low efficiency. At the district level, only Chenghua District’s park was spatial equitable and efficient, surpassing the average level of the main urban area. Finally, we discussed the findings in the context of planning policies for Chengdu in recent years. We proposed that strengthening the construction of small urban parks and green spaces, improving park facilities to meet the diverse social needs of people, and enhancing the quality and attractiveness of the parks are crucial for the future development of park green spaces in the main urban areas of Chengdu.     

耕地空间保护格局影响因素及整治规划对策——以甘肃省平凉市崆峒区为例

[目的]通过对耕地保护现状空间格局成因及其空间相关性分析,划分科学的耕地整治规划分区,为进一步优化崆峒区耕地布局,提升耕地质量,科学利用、保护耕地提供参考。[方法]以甘肃省平凉市崆峒区为例,采用景观格局指数法、多目标决策法、Spreaman秩相关法、聚类分析法,选取耕地坡度、耕地保护政策、城镇化影响来分析耕地景观格局现状与其在空间上的存在的协同或权衡关系,构建耕地保护格局相关性分析评价指标体系。[结果](1)研究区整体上耕地景观格局指数2010—2022年上升3.55%,耕地集聚程度大部分区域呈现下降趋势,但在整个过程中呈现波动。区域土地利用程度整体上呈上升趋势,各乡镇耕地布局特征及土地利用程度差异明显。(2)耕地保护指数2022年较2010年上升315.30%,2°～6°耕地增加120.96%,15°～25°耕地减少32.64%,>25°耕地减少100%,耕地质量提升明显,与耕地景观格局在空间上高度协同;城镇化影响指数呈上升趋势。2010—2022年城镇化影响指数上升25.17%,城镇化对耕地布局影响加大,与耕地景观格局在空间上存在权衡关系。(3)划分耕地质量提升重点区、耕地质...     

安庆市大气污染现状及防治对策探究

随着经济发展,城市化进程的加快,城市大气环境污染问题受到广泛关注.治理大气污染,改善城市环境空气质量,是建设生态文明城市的关键.以安庆市为例,探究了安庆市大气污染的现状,讨论了污染的特点及成因,并结合实际提出了健全完善的环保立法、优化产业结构、发展城市绿色交通、提高公众环保意识等防治对策,为防治大气污染、提高城市大气环...