Exploring long-term land cover changes in an urban region of southern Europe

This paper addresses two important issues for large Mediterranean city regions: the differential impact of compact urban ‘growth’ and low-density ‘sprawl’ on land cover changes (LCCs), and their final effect on changing land cover relationships (LCRs). The urban expansion of Rome (Italy) during the last 50 years and the related LCCs were investigated as a paradigmatic example of compact versus dispersed urban development. LCCs were assessed over 5 years (1960, 1974, 1990, 2000, 2006) by analysing diachronically the distribution of 12 land cover categories derived from digital land cover maps covering the entire Nuts-3 prefecture of Rome (5353 km²). LCRs were studied using multi-way data analysis. LCCs were found to have relative differences during ‘growth’ (1960–1990) and ‘sprawl’ (1990–2006) phases. Conversion to urban land uses concentrated in the 1960s and 1970s at the urban fringe, while expanding progressively far from the city in the 1990s and 2000s. During the ‘growth’ phase, the land cover classes with the highest probability of being converted to urban uses were arable lands, annual crops, vineyards and pastures. During the ‘sprawl’ phase, olive groves, orchards and forest surfaces also decreased due to the development of low-density built-up areas and infrastructure. Planning suggestions aimed at mitigating the alteration of the rural landscape through sprawl conditions are discussed.     

Climate change,risk management and the end of Nomadic pastoralism

Mobility has been argued to be the single factor explaining why some pastoralists do relatively well during extreme climatic events, while others do not, because mobility works by taking advantage of the spatial and temporal structure of resource failure by moving away from scarcity towards abundance. In spite of this, a common governmental management strategy is to resettle pastoral populations and thereby significantly reduce mobility. By revealing the underlying logic of mobility for Tibetan pastoralists, this paper questions official policy that aims at privatizing communally owned rangelands since it reduces pastoral flexibility and access to key resources. This is especially pertinent in the face of climate change. While little is known as to the specifics of how climate change will affect nomadic pastoralists, environmental variability is likely to increase. Consequently, policies resulting in decreased mobility may exacerbate the negative effects of climate change because of a positive feedback between climate and negative density dependence.     

A case study of flood control schemes for the Kakehashi river and their socio-cultural consequences

SUMMARY

This paper is concerned with a twenty-five year campaign against the relocation of the Komatsu-Tenmangu shrine as a result of the enlargement of the Kakehashi river. The Komatsu-Tenmangu shrine is an important cultural property of Japan, and was constructed by Toshitsune Maeda, the third dynasty of the Kaga clan in 1657. It is suggested that the primary reason why it took so long to settle this issue is a flaw in our social system for managing public works. It is concluded that preservation of cultural property is not always contrary to land development, and that the proposed procedures or something like them must be put into practice for the real expansion of our culture.     

Towards a sustainable future: a holistic inquiry of waste management behaviors of Singapore households

ABSTRACT

In 2018, Singapore produced a 7.7 million tonnes of waste, which is a significant amount of waste for a small nation-state. In line with the Sustainable Development Goal (SDGs) targets 11.6 and 12.5 of the 2030 Agenda, which addresses cities’ waste generation and management impacts, we ask the question of why Singapore households are not more proactively engaged in waste minimization, despite the presence of local waste minimization public campaigns. This study is the first known study to comparatively apply and test three major theories – social psychological, social-structural, and sociocultural theories, to explain household waste management behavior in Singapore. A national survey followed by regression analysis of 303 households was conducted. In our findings, we firstly describe current trends in household waste management behaviors. Secondly, we compared each applied theory’s ability to predict households’: (1) reuse and (2) recycling of a variety of household items; and (3) recycling frequency. We obtained partial evidence supporting the role of future-orientedness and environmental identity on householders’ variety reuse and recycling. Social-structural (age cohort x income, education) and situational variables (the convenience thesis), also predicted various waste minimization behaviors. Finally, householders’ knowledge of what is recyclable affected all forms of waste minimization behaviors. In view of the study’s findings, we propose a need for targeted planning and policy interventions for different segments of the Singapore population, and different short- and longer-term measures to initiate and achieve sustained household waste minimization.     

Benefits and challenges of streamlined life-cycle assessment for SMEs – findings from case studies on climate change impacts

ABSTRACT

Small and medium-sized enterprises (SMEs) have a substantial role in the economy and job creation, but they are a remarkable source of environmental impacts. SMEs often lack skills and resources to compile environmental impact assessments; Streamlined Life Cycle Analysis (LCA) can provide efficient tools for this. An application of streamlined LCA relying heavily on database data, LCA clinic, was developed and tested on 23 SMEs in Finland. The climate change impacts were mainly caused by the production of raw materials, electricity and heating, whereas packaging and transportation were not influential. A significant amount of emissions were indirect, i.e. caused by production of raw materials. Thus, decreasing emissions from raw material production or selecting raw materials with a smaller environmental load could be a more efficient way to decrease emissions than reducing direct emissions such as those from electricity use. Lack of data in the LCA-databases was considered a challenge. An access to regionally customised datasets is important for the implementation of LCA clinics. Company feedback indicated that LCA clinics were useful in climate-friendly product design and increased environmental awareness, but did not lead to immediate actions to reduce emissions because of inadequate investment capabilities. Company managers had limited possibilities to use the results in marketing as comparative assessments would require a full LCA. Many company managers were willing to pay a fee sufficient to cover the costs of an LCA clinic, but some considered that the costs should be covered by external funding sources.     

不同区域气候条件影响下的纳帕海湿地植物叶绿素荧光特性

采用原位移地技术,研究了不同区域气候条件影响下,纳帕海4种常见湿地植物的株高、茎粗、生物量等生长特性,以及叶绿素a、叶绿素b、总叶绿素含量、叶绿素a/b值、光化学量子效率（Fv/Fm）、电子传递速率（ETR）、实际光化学量子效率（Phips2）、光化学猝灭系数（qP）、非光化学猝灭系数（NPQ）等生理生化指标,分析探讨了湿地植物对不同区域气候条件的响应差异和适应策略。研究发现气候条件的改变对湿地植物的生长、叶绿素含量及荧光参数产生重要影响。随着温度的上升,水葱Scirpus tabernaemontani和茭草两种广布种Zizania caduciflora均表现出良好的适应性,生物量、叶绿素含量、Fv/Fm、ETR、Phips2、qP值不同程度升高,生长状况良好。刘氏荸荠Heleocharis liouana也表现出较好的适应性,当气温上升到一定程度后,虽然Fv/Fm、ETR、Phips2、qP值降低,但其通过调节叶绿素含量、热耗散来减轻伤害,气候变化对其生长的影响较小。而北温带分布型的黑三棱Rhizoma scirpi yagarae对气候变化的适应性较差,当温度上升到一定程度后, Fv/Fm、ETR、Phips2、qP、NPQ都出现大幅下降,生长停滞,生物量下降,对温度上升极为敏感。可以推测,随着全球变暖,像黑三棱这样的物种,其生存将面临极大的威胁,而高原湿地生态功也将能受到损害。     

降水变化、氮添加对鼎湖山主要森林土壤有机碳矿化和土壤微生物碳的影响

全球变化对土壤有机碳(SOC)存贮与分解的影响在全球碳(C)循环中具有重要地位.分别通过室内土壤培养法和氯仿熏蒸法,研究了降水变化和氮(N)添加处理对鼎湖山3种不同演替阶段的季风常绿阔叶林、针阔混交林和马尾松针叶林SOC矿化和土壤微生物量碳(SMBC)的影响.结果表明:1)降水量增加能够提高森林演替晚期SOC累积矿化量和矿化速率,而对森林演替早期SOC累积矿化量和矿化速率没有显著影响(P>0.05).2)干旱条件(降水量减少)降低森林SMBC含量,且在鼎湖山季风林表层土壤(0～10 cm)中SMBC的减少达到显著水平(P<0.05).3)N添加处理对鼎湖山3种森林类型SOC累积矿化量、矿化速率以及SMBC都没有显著影响(P>0.05).未来关于SOC矿化对全球变化响应的研究,要综合考虑土壤有机质质量、C/N比例、外源性氮输入等因素的作用.图4表2参37     

土地利用方式对土壤动物多样性的影响

为了解不同利用方式下土壤动物多样性状况及其演变,对广州市东部郊区的水稻田、蔬菜地、果园旱地和林地4种土地利用类型0～5、5～10、10～15、15～20cm土层进行了土壤动物取样调查,共获得土壤动物24683只,分别隶属于4门10纲23类。统计分析结果表明,土壤动物多样性受土地利用方式的影响明显。果园旱地和林地的个体数显著高于蔬菜地和水稻田,但果园旱地与林地、蔬菜地与水稻田之间无显著差异;果园旱地和林地的土壤动物类群数显著高于水稻田,但果园旱地与林地、林地与蔬菜地、蔬菜地与水稻田之间的差异不显著;林地和果园旱地的复杂性指数显著高于蔬菜地,但林地与果园旱地和水稻田、水稻田与蔬菜地之间的差异不显著（P〈O．05）。土壤动物的个体数和类群数量随着土壤深度的增加而明显减少,但不同土地利用方式下各层土壤动物的丰富度及其随土层加深而递减的程度则有明显不同,其中,林地和果园旱地的土壤动物在不同土层中较丰富,垂直变化比较和缓,水稻田和蔬菜地的类群数和个体数则随土层的加深而急剧减少。     

安徽省会经济圈土地利用变化的碳排放效益

土地利用变化是影响碳排放的重要因素。利用1997和2007年土地利用类型数据,采用碳排放评价模型,对安徽省会经济圈碳排放效益进行评价,并估算碳排放生态补偿标准。研究结果显示:①1997-2007年间碳排放总量增加1 049.92×10⁴ t,年均增长14.4%;②2007年经济圈内地均建设用地碳排放强度和地均碳排放强度分别为1997年的2.41倍、 2.18倍,1997和2007年,碳排放强度指数值都是合肥市>巢湖市>六安市;③经济圈内各县(区)地均碳排放强度差异显著,建设用地平均碳排放强度前3位的是合肥市区、 霍山县、 金寨县;④据中国造林成本的价格估算,合肥、 巢湖、 六安3市的碳汇补偿增加量分别为:21.83×10⁸、 4.31×10⁸、 2.48×10⁸元,县域生态补偿额差异显著;⑤土地利用结构、 产业结构与碳排放量存在一定的关系。从碳排放效益和生态补偿的角度,提出减少碳排放的途径。     

Unregulated urban sprawl and spatial distribution of fire events: evidence from Greece

Fire events are an annual phenomenon in Greece with damages and even casualties, making their understanding and management important. In this paper, we present fire events provided by NASA Fire Information for Resource Management System and place them along a number of spatial types defined by relief and land cover classes. Results demonstrate that the occurrence of fire events is related more to some land cover classes than others. The most important in terms of overall frequency in all types of terrain is ‘Agricultural Areas’, as a result of farming practices that involve fire. The second more important type of areas is ‘Artificial Surfaces’, especially in low lying areas. These events are related to urban growth and sprawl and are very often a direct outcome of speculation practices with land properties, encouraged by the absence or poor implementation of spatial planning.