重庆旧城改造区土地覆被与景观格局变化——以北碚区为例

以重庆市北碚区为例,以2001、2006和2011年三个时期的土地利用变更调查数据库数据为基础数据,借助GIS技术,对旧城改造区的土地利用/覆被与景观格局进行分析,结果表明:2001—2011年的10年期间,区域始终以农用地为主要覆盖类型,一级农用地变化幅度不大,农用地下的二级地类发生较大转变,其他农用地向林地及园地发生大幅转化,主要原因是北碚规划建设生态型新城区;建设用地不断增加,到2011年达到区域18.03%占有量,建设用地主要由未利用地转化而来;2001—2011年,区域景观破碎度呈现由小破碎度到大破碎度再到小破碎度的趋势,到2011年破碎度达到最小值;区域各地类的分维数呈现增加趋势,说明自然景观受人为因素的影响越来越大。     

Integrating ecosystem services into conservation assessments: A review

A call has been made for conservation planners to include ecosystem services into their assessments of conservation priority areas. The need to develop an integrated approach to meeting different conservation objectives and a shift in focus towards human wellbeing are some of the motivations behind this call. There is currently no widely accepted approach to planning for ecosystem services. This study contributes towards the development of this approach through a review of conservation assessments and the extent to which they include ecosystem services. Of the 476 conservation assessments identified by a set of search terms on the Web of Science, 100 were randomly selected for this review. Of these only seven had included ecosystem services, while another 13 had referred to ecosystem services as a rationale for conservation without including them in the assessment. The majority of assessments were based on biodiversity pattern data while 19 used data on ecological processes. A total of 11 of these 19 assessments used processes, which could be linked to services. Ecosystem services have witnessed an increase in attention received in conservation assessments since the year 2000, however trends were not apparent beyond this date. In order to assess which types of ecosystem services and how they have been accounted for in conservation assessments, we extended our review to include an additional nine conservation assessments which included ecosystem services. The majority included cultural ecosystem services, followed by regulatory, provisioning and supporting services respectively. We conclude with an analysis of the constraints and opportunities for the integration of ecosystem services into conservation assessments and highlight the urgent need for an appropriate framework for planning for ecosystem services.     

黑龙江省典型城市合理用地规模确定的实证研究——以大庆市为例

以黑龙江省典型的资源型城市——大庆市建成区为研究对象,用1990—2004年的数据建立经济数学模型。利用Excel软件分析了城市用地规模与经济发展水平之间的关系,表明两者呈相互关联的非线性变化规律。假定在同一技术条件下,采取成本—效益模型计算出确保城市经济效益最优时的土地面积即为合理用地规模,通过计算城市空间扩展度,得出现有城市用地规模大于合理用地规模的结论,在今后的经济发展中应考虑适当地控制城市用地规模。     

区域耕地保护补偿分区实证研究

由于我国各地自然、经济、社会条件的差异,区域间耕地保护补偿关系必然不同。依据外部性理论,采用人均耕地阈值方法,将全国31个省级行政区划分为耕地赤字区、耕地平衡区以及耕地盈余区,确定了省级层面耕地保护补偿关系。分区结果显示:全国耕地赤字区12个省份,耕地平衡区8个省份,耕地盈余区11个省份,并将补偿分区与我国传统粮食分区进行比较,显示出了我国耕地资源的恶化趋势及补偿的迫切性。分区结果为耕地保护区域横向补偿额度及其流向提供了方向性指导。     

转型期农村土地冲突爆发原因探究

农村土地冲突不仅影响农村土地资源配置及其效率,而且对我国的社会转型、农村社会和经济稳定发展具有重大意义。分析了农村土地冲突的概念和类型,并从土地资源的天然局限性、农村土地制度的设计缺陷、农村土地的社会保障作用和村委会自治权异化的角度探究了转型期农村土地冲突爆发的原因,为进一步化解农村土地冲突提出努力方向。     

快速工业化地区中心镇的土地经营

在快速工业化地区的城镇发展过程中,尤其是经济较发达的中心镇,面临着城镇建设用地迅猛扩张和土地资源有限的重重矛盾。把土地作为资产来经营是中国土地供给制度改革的核心,也是其改革取得成功的关键。为了有效合理地配置快速工业化地区中心镇土地资源,提高土地利用率,在快速工业化地区的中心镇实行土地经营既有可能也有必要。并对中心镇实行土地经营的思路进行探索,包括实行土地经营原则、内容、模式及不同类型的城镇建设用地的经营策略。     

国际上土地利用／土地覆盖变化研究的新进展

进入90年代以来,随着全球人口,资源与环境问题的日益突出,土地利用／土地覆盖变化（LUCC）研究已成为国际上全球变化研究的前沿与热点课题,在研究内容与方法上出现了很多新的趋势,本文将对目前国际上土地利用与土地覆盖变化研究的新进展进行介绍,以为我国开展此方面的研究提供参考。     

Land Allocation between Food and Energy

Many countries are promoting biofuels as a substitute for scarce oil. This paper develops a dynamic model of land allocation between food and energy and shows how the model can be calibrated using standard optimization techniques. Some possible implications of the trade-offs between food and energy are discussed. Specifically, we show that the effect of mandates is mainly felt through increased land conversion, which increases indirect carbon emissions Crude oil prices do not decrease significantly because of leakages.     

青岛德租时期城市园林规划与设计探析

德国租借时期的青岛园林在中国近代园林中独树一帜,是世界范围的造林典范,是从造林到造园的成功探索,城市层面的建设意义突出。以史志、老照片、规划图与建设状况图等史实为依据,结合现场调研,梳理青岛园林规划,揭示其城市设计、科学生态、林业生产以及经济实用的规划思想。考证出公园、绿地以及林荫道布局在城市重要功能区;这些公园绿地既受到德国近代思潮的影响,又在地域环境中追求自然之美与森林化景观效果。希望理清青岛德国租借时期园林建设的状况,对当前我国城乡园林建设有所启发。     

An introduction to rural and agricultural development in the digital age

This special issue contributes to the development economics literature by highlighting the role of information communication and technologies (ICTs) in supporting rural and agricultural development. It is comprised of nine papers. Key findings from this special issue include: (1) internet use increases rural consumption diversity and agricultural productivity; (2) smartphone use empowers rural women in household decision-making and off-farm work participation; (3) smartphone-based agricultural extension services boost rural income growth; (4) a lack of ICT infrastructure and inadequate skills to use digital technologies are two key factors that lead to digital poverty traps for smallholder rural farmers; (5) ICT adoption increases the probability of rural households' access to credit and empowers rural women and farm households in relatively less developed regions to access credit; (6) digital financial inclusion reduces farmers' vulnerability to poverty; and (7) e-commerce adoption increases both sales prices and marketing costs, but the magnitude of increasing the former is higher than the magnitude of increasing the latter, which finally contributes to a higher gross return. This special issue also proposes practical instruments and implications for advancing the application of ICTs in rural areas to accelerate rural and agricultural development in the digital age.