乡村振兴背景下农村土地开发困境与路径优化研究 ——基于公共、集体和个人利益比较视角

乡村振兴战略下我国农村土地开发面临 着多元主体利益冲突与协调困境。以四川省3个村 庄作为研究对象,采用多案例对比、多主体分析 的研究思路,分别解析政府主导、市场主导、村 集体主导三种村庄土地开发路径的开发过程与 驱动机制,并总结其在利益分配方面的困境或不 足。研究结果表明,在公共利益、集体利益和个 人利益的博弈中,开发主体及行为动机差异是造 成利益冲突困境的根本原因。其中,政府和市场 主导的村庄土地开发存在较多的利益分配不协调 问题,而村集体主导能够较好地协调公共、集体 和个人利益的关系。在农村土地开发过程中协调 处理好利益主体的相互关系是解决问题的关键, 应当通过开发主体限制、平台构建、利益联结和 协商机制的确立,实现可持续的农村土地开发与 乡村振兴战略的全面推进。     

深圳市建成环境因素对居民通勤效率的影响 ——基于手机信令数据的分析

通勤效率是反映城市生活品质的重要 指标。改革开放以来,经济社会快速发展和城 镇化水平不断提高,城市职住空间关系发生深 刻变化和居民通勤行为变得日趋复杂,影响城市 空间绩效和居民生活品质;且随着多源大数据 可获得性增强,关于职住平衡及其对通勤效率 作用机制的研究愈发广泛而深入,但学者对于 职住平衡度和土地利用混合度等物质空间属性 如何影响居民通勤尚未达成一致的结论。为了 解城市日常生活中不同通勤效率居民的多元需求 和真实的通勤状态,探索提升城市居民通勤效 率的有效途径,推动城市人居环境高质量发展。 以深圳市为例,借助DAAS和ArcGIS平台利用 联通手机信令数据识别居住地和工作地,通过 LINGO软件计算过剩通勤指标,对深圳居民通 勤效率进行评价,并在区分居民工作地和居住地基础上建立多元回归模型,探究多方面因素对居民通勤效率的影响和作用机制。研究发现,区 位、职住平衡度、土地利用混合度、容积率、平均房价、公交可达性、城中村面积、工作岗位数量 和服务设施面积对居民通勤效率有重要的影响。控制其他因素对通勤效率的影响之后,无论是 居住地还是工作地,通勤效率都会随着职住平衡程度的提升而提高,而在中国已有较高密度和 混合度的背景下,通过进一步增容或功能混合以期提高通勤效率的措施则需审慎对待。研究丰富 了基于我国大中城市背景的通勤影响实证案例,为提高城市通勤效率,推动可持续交通提供有益 的政策参考。     

新时期空间规划转向与政策绩效提升路径

公共政策限制或扩展了人的行为, 以此牵引空间需求并塑造城乡形态。而城乡 规划的本质即是人类社会对空间需求的集体 意志,是权衡社会、文化、经济和环境等无 边界因素之后的集体选择。城乡规划在新时 期融入了国土空间规划体系,但由于边界不 明确、作用机制不明朗、效果不直接、责任难 认定等原因,在积极贡献的同时,承受了较多 质疑甚至不实之责。为了更加清晰地认知空 间规划及其政策,可以借鉴西方城市发展和 规划理论探索经验,重新认知和区分规划领 域学理、法理、机理的内涵与差别,同时,探 讨提升空间规划政策绩效的路径,大体包括 推动经验判断转向情景演算、识别实施传导 机制、划定可试错的领域并完善纠错机制以 及促进规划政策全过程的知识积累等方面。     

上海郊野地区规划的创新探索

在“新型城镇化”和“生态文明”的国家战略指导下,上海借助土地综合整治平台积极推动城市的可持续发展。将城乡规划与土地规划结合,在郊野地区①构建土地整治规划体系,并通过集建区内外的管理联动,使郊野地区规划在纵向、横向上实现全覆盖和“三化”管理②,是上海规划和土地工作的一次创新,也是实现城乡统筹目标的途径之一。在阐明当前郊野地区规划编制主要问题和必要性基础上,介绍郊野地区规划体系、区县土地整治规划、郊野单元规划、郊野公园规划4个方面创新性探索成果,并提出“3个转变”的规划思考。     

Increase in energy and land use by a bio-based chemical industry

About 80% of the chemical products are still based on crude oil. Bio-based materials will increasingly gain importance. As the fraction of oxygen is normally higher in biomass than in crude oil as well as in the derived conventional products, this implies a need to develop new synthesis pathways. Depending on the types of new synthesis pathways, the effects of a complete raw-material change on land and exergy use differ. Here, different synthesis pathways starting from glucose and plant oil to different kinds of end products are evaluated utilizing material and exergy balances. These evaluations are carried out under today's and future conditions and constraints, like yield, demand of organic chemicals and world population. The analysis in this paper shows that the land and energy use can be significantly reduced, if the products are adapted to the chemical structure of their bio-based feedstock.     

Polaroid,Aperture and Ansel Adams: Rethinking the Industry-Aesthetics Divide

This article takes the history of Polaroid photography as an opportunity to question a presupposition that underpins much thinking on photography: the split between industrial (i.e. useful) applications of photography and its fine art (i.e. aesthetic) manifestations. Critics as ideologically opposed as Peter Bunnell and Abigail Solomon-Godeau steadfastly maintain the existence of this separation of utility and aesthetics in photography, even if they take contrasting views on its meaning and desirability. However, Polaroid, at one time the second largest company in the photo industry, not only enjoyed close relations with those key representatives of fine art photography, Ansel Adams and the magazine Aperture, but it also intermittently asserted the ‘essentially aesthetic’ nature of its commercial and industrial activities in its own internal publications. The divide between industry and aesthetics is untenable, then, but this does not mean that the two poles were reconciled at Polaroid. While Aperture may have underplayed its commercial connections and Polaroid may have retrospectively exaggerated its own contributions to the development of fine art photography, most interesting are the contradictions and tensions that arise when the industrial and the aesthetic come together. The present article draws on original research undertaken at the Polaroid Corporation archives held at the Baker Library, Harvard, as well as with the Ansel Adams correspondence with Polaroid, held at the Polaroid Collections in Concord, Massachusetts.     

Measuring the neighbourhood effect to calibrate land use models

Many spatially explicit land use models include the neighbourhood effect as a driver of land use changes. The neighbourhood effect includes the inertia of land uses over time, the conversion from one land use to another, and the attraction or repulsion of surrounding land uses. The neighbourhood effect is expressed in the neighbourhood rules, but calibration of the neighbourhood rules is not straightforward. This paper aims to characterise the neighbourhood effect of observed land use changes and use this information to improve the calibration of land use models. We measured the over- and underrepresentation of land uses in the neighbourhood of observed land use changes using a modified version of the enrichment factor. Enrichment factors of observed land use changes in Germany between 1990 and 2000 indicate that the neighbourhood effect exists. This suggests that it is appropriate to use neighbourhood rules to simulate urban land use changes. Observed enrichment factors were used to calibrate a land use model for Germany from 1990 to 2000 and the obtained neighbourhood rules were validated independently from 2000 to 2006. The results show that both the allocation accuracy and the pattern accuracy of the land use model improved for the calibration period, as well as for the independent validation period. This indicates that enrichment factors can be used to improve the calibration of the neighbourhood rules in land use models.     

Agronomic and environmental effects of land application of residues in short-rotation tree plantations: A literature review

Land application of residues in short-rotation plantation has a priori the double advantage to meet the nutrient needs of these tree plantations at lower cost while recycling residues. Agronomic and environmental effects of a very wide variety of residues on plants and soils have been studied worldwide. I attempt here to compile and to summarize the results of the studies about the effects of land applications of residues (mostly organic) in plantations or under controlled pot conditions of the three species mostly used for short-rotation coppice: willow, poplar, and eucalyptus. The spreading of most residues causes an enrichment of the soil in nutrients and a subsequent increase in the growth of plants. Manure, compost, sewage sludge, and wastewater seem most effective in stimulating growth. Ashes have less impact on growth. Few negative effects on the plant have been highlighted in response to spreading, except in the case of very rich effluents in salt in response to which growth reduction and leaf loss nevertheless did not lead to plant death. The high transpiration potentials of the fast growing species dedicated to intensive tree plantations allow them to absorb and tolerate, without major damages, nutrients in excess, most heavy metals, and antibiotics. In some cases, heavy metal accumulation in soils following the spreading of residues, but few of them showed leaching or water pollution. Nevertheless, the used doses and the intervals between applications were of primary importance to avoid leakage of undesirable elements in the environment.     

A novel approach to mapping land conversion using Google Earth with an application to East Africa

Effective conservation planning relies on the accurate identification of anthropogenic land cover. However, accessing localized information can be difficult or impossible in developing countries. Additionally, global medium-resolution land use land cover datasets may be insufficient for conservation planning purposes at the scale of a country or smaller. We thus introduce a new tool, GE Grids, to bridge this gap. This tool creates an interactive user-specified binary grid laid over Google Earth's high-resolution imagery. Using GE Grids, we manually identified anthropogenic land conversion across East Africa and compared this against available land cover datasets. Nearly 30% of East Africa is converted to anthropogenic land cover. The two highest-resolution comparative datasets have the greatest agreement with our own at the regional extent, despite having as low as 44% agreement at the country level. We achieved 83% consistency among users. GE Grids is intended to complement existing remote sensing datasets at local scales.     

Hangzhou

Once an ancient capital of China, Hangzhou has transformed to a post-socialist city that faces profound changes and critical challenges in various aspects of urban development such as historical legacies, market-oriented urban economy, expansive urban spatial patterns, population management, land use restructuring, and affordable housing provision. Under the increasingly stronger market power, the city strives to reposition itself to be an important economic center in the Yangtze River Delta Region, through strategic and innovative urban growth agenda. This profile identifies some fundamental issues and processes that underscore Hangzhou’s recent urban development and presents future prospect for a coastal metropolis with regional significance.