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131.
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. 相似文献
132.
Tom Finch Simon Gillings Rhys E. Green Dario Massimino Will J. Peach Andrew Balmford 《Conservation biology》2019,33(5):1045-1055
Empirical evidence from many regions suggests that most species would be least negatively affected if human food demand were met through high-yield agricultural production and conservation of nonfarm ecosystems (land sparing), rather than through wildlife-friendly farming over a larger area (land sharing). However, repeated glaciation and a long history of agriculture may lead to different results in regions such as western Europe. We compared the consequences of land sparing and land sharing on breeding bird species in 2 lowland regions of England, The Fens, with 101 species, and Salisbury Plain, with 83. We derived density–yield responses for each species and then estimated regional population size under regional food production strategies, including land sharing and land sparing, a range of intermediate strategies, and a novel mixed strategy. In both regions, more species achieved maximum regional population size under land sparing than land sharing. In The Fens, the majority of birds were loser species (estimated to have smaller populations under all food production strategies than in the preagricultural baseline scenario), whereas in Salisbury Plain the majority were winners (smaller populations in the preagricultural baseline scenario). Loser species overwhelmingly achieved maximum regional population size under land sparing, whereas winner species achieved maximum regional population size under either land sharing or an intermediate strategy, highlighting the importance of defining which groups of species are the target of conservation. A novel 3-compartment strategy (combining high-yield farming, natural habitat, and low-yield farming) often performed better than either land sharing or land sparing. Our results support intermediate or 3-compartment land-sparing strategies to maximize bird populations across lowland agricultural landscapes. To deliver conservation outcomes, any shift toward land sparing must, however, ensure yield increases are sustainable in the long term, do not entail increased negative effects on surrounding areas, and are linked to allocation of land for nature. 相似文献
133.
S. Kim 《国际发展与全球生态学杂志》2019,26(2):141-153
The impact of large-scale urban development on land resources has long been debated by urban planners and designers. This study investigated the extent to which different urban characteristics are associated with land-cover change. The Yangtze River Delta region in China, forming one of the largest sprawling urban landscapes among the regions around the world, was chosen for the study area. Spatial analysis and multiple regression methods were applied to empirically investigate the pattern of resource sites lost to urban development in the area between the 1950s and 2017. The results showed that contrary to the widespread notion that large-sized cities are predominantly responsible for a region’s environmental degradation, city size was not a significant factor in determining the rate of resource loss. Large-sized cities gained their populations with far lesser impacts on land than small-sized cities and towns if normalized to the same number of populations. One explanation for the diminishing effect of city size on land-cover change relates to the degree of spatial dispersion of urban development and local differences in social valuation of diversified lands by cities. 相似文献
134.
Binoy Sarkar Hong Lim Choi Kun Zhu Asit Mandal Bhabananda Biswas Arumuganainar Suresh 《Chemistry and Ecology》2016,32(5):407-418
Under the intensive agricultural system, direct application of animal slurries to soils can provide a sustainable disposal of these wastes by inducing positive changes in soil quality and fertility. However, how animal wastes quantitatively affect the key nutrients (C, N, P and S) transforming soil enzymes is not clearly known. A greenhouse spinach cultivation study demonstrated that pig slurry, either in raw (RS) or processed (aerobically aged) (PS) form, significantly (p?β-glucosidase (23–39%), urease (59–103%), nitrate reductase (73–103%) and dehydrogenase (27–72%)) and microbial growth in soil as compared to the unamended control. However, it did not significantly (p?>?.05) alter the aryl sulphatase enzyme activity. Slurry applications also significantly improved the macro (N, P and K) and micronutrients (Cu, Mn, Zn and Fe) uptake by spinach plant and hence the yield (2.9–3.38 times higher than control). Similarly, compared to chemical fertilisers the application of pig slurries improved soil biological and biochemical parameters as well as plant nutrients uptake. This study demonstrated the closing of global energy and nutrient cycles through land application of animal wastes without compromising the crop yield. 相似文献
135.
Patrick Meyfroidt 《Journal of Land Use Science》2016,11(5):501-522
Research into land and social-ecological systems science could benefit from improved clarity in the terminology used for causal analysis and a structured way to make causal inferences. Here I identify two aspects of causality, i.e. causal effects and causal mechanisms, and discuss explanation in historical sciences. I then propose definitions for the major terms used for causal relations, including driver, (spatial) determinant, location and contextual factor, proximate and underlying factors. Finally, I discuss the contribution of various operational approaches, including time series and counterfactual approaches for assessing causal effects and process-tracing approaches for establishing causal mechanisms. Having a coherent concept of causality, agreeing on a precise vocabulary and harnessing our tools with the clear purpose of establishing both causal effects and causal mechanisms should strengthen causal explanations for single cases, for drawing policy-relevant lessons and for theoretical development in relation to land and, more broadly, social-ecological systems processes. 相似文献
136.
Olanrewaju Lawal 《Journal of Land Use Science》2016,11(2):222-235
The incorporation of land use (LU) data with socioeconomic data is a main issue in modelling. This is as a result of difference in data model and scale. This study proposed and tested the change–pattern approach, which allows the incorporation of these data sets in modelling LU change. Focusing on LU dynamics for a selected part of the Thames Gateway within the City of London, the approach tested two different methods of input selection for the modelling operations. Variables selected from these two methods serve as inputs into several neural networks tested in order to identify the direction of change for each of the LU types within the study area. The result shows that direction of LU change across the study area could be identified when spatial morphology of the area and socioeconomic variables are considered. Some classes of change could be identified fairly accurately using landscape metrics indicating level of fragmentation, extent of LU patches, shape complexity of LU patches in combination with some socioeconomic variables. 相似文献
137.
土壤饱和导水率（Ks）是土壤水文循环中的关键参数,然而当前对毛乌素沙地Ks的特征及影响因素还认识不足。通过测定毛乌素沙地4种土地利用方式下（农田、乔木、灌木和草地）0—100 cm土层的Ks和土壤基本理化性质（有机质、容重及颗粒组成）,分析Ks的垂向变异性及其影响因素、建立估算Ks的传递函数。研究表明：农田、乔木和灌木地的Ks随着土层深度增加而逐渐增大,草地无明显变化。4种土地利用方式下的Ks均为中等程度的垂向变异性,平均值排序为草地（1.38 mm·min−1）＜乔木（1.76 mm·min−1）＜农田（1.82 mm·min−1）＜灌木（3.30 mm·min−1）,其中灌木地的Ks显著高于其他土地利用方式（P＜0.05）。Ks与有机质、容重、土壤颗粒组成存在显著相关性,通过提取Ks的主导因素,用逐步多元回归方法建立了估算Ks的传递函数。相关研究有助于毛乌素沙地Ks参数的获取和预测。 相似文献
138.
梳理了河湖库清淤底泥农用地利用相关概念及其主要方式,分析了清淤底泥农用地利用相关法律法规以及国家标准、行业标准和地方标准.河湖库清淤底泥农用地利用以土壤改良剂、土料或以两者相结合的利用方式,可用于农田土壤改良、土壤肥力提升、耕地复垦以及矿坑修复、宕口治理、湿地修复、低洼地改造等.清淤底泥农用地利用是消纳大宗清淤底泥的重要途径,可实现生态效益、社会效益和经济效益互促共赢.我国已初步建立起以《中华人民共和国土壤污染防治法》为核心的农用地土壤污染防治法律法规体系,《土壤环境质量农用地土壤污染风险管控土壤标准(试行)》(GB 15618-2018)是生产可食用农产品的农用地土壤污染风险管控主要标准.清淤底泥农用地利用风险管控的核心要求是\"禁止使用可能造成土壤污染的清淤底泥\".目前缺乏清淤底泥应用于农用地中其它类型土地的污染物控制国家标准,建议加快研制清淤底泥应用于其它类型农用地标准.现阶段建议根据保护目标确定土壤污染物含量控制标准,并遵循\"清淤底泥产物中污染物含量应不高于施用地土壤中相应的含量\"的原则.清淤底泥经处理后作为GB 15618-2018未规定的农用地土壤或农用地下层土壤填充物料时,应重点管控污染物生态风险及其随水分运移对表层土壤、地下水产生的环境风险,必要时应评估对农产品质量安全可能存在的影响和风险.《土壤质量决策单元-多点增量采样法》(GB/T 42489-2023)可用于淤泥理化性质和污染物含量测定的采样方法,在确保数据准确性和结论可靠性的基础上,合理控制样品数量,降低监测检测费用. 相似文献
139.
Inspired by the phenomenon of heavy reduction in the area of cultivated land following the entry of Korea and Japan to the WTO,countries with a large population and inadequate amount of cultivated land similar to China,this paper raises the problem of the potential effects on cultivated land in China following its entry to the WTO.The paper attempts analysis,using economic principles,of the effects of Chinese WTO membership on cultivated land from four aspects;tariff concessions,quota increment,comparative advantage,and the substitution principle.And the conclusion is mat China's entry to WTO may lead to a reduction in cultivated land.Finally,some countermeasures are proposed to resolve the problem. 相似文献
140.
“结构—行为—绩效”框架下农地整理的管护绩效研究 总被引：1，自引：0，他引：1
在分析农地整理建后管护基本内涵的基础上开发了农民满意度绩效量表,引入新制度经济学领域"结构—行为—绩效"(SCP)范式,构建农地整理建后管护的"组织结构—管护行为—管护绩效"的分析框架。以湖北省赤壁市黄盖湖农场和嘉鱼县潘家湾镇为研究区域开展实证研究,通过比率标度法和熵权法生成绩效测度的组合权重并得到满意度绩效,运用调查数据检验建后管护的组织结构和管护行为对管护绩效的影响机理,分析组织结构的工作职能、成长机制以及管护行为中的集体行为和个体行为的影响程度。研究结果显示:受访农民对农地整理的管护绩效评价接近于"一般",企业管护模式下黄盖湖农场和集体管护模式下潘家湾镇的管护绩效存在显著的地区差异;表征管护组织持续发展状态、内部结构完善程度的组织结构类变量以及表征管护资金投入、受益农民群体参与程度的管护行为类变量是显著影响管护绩效的解释变量;黄盖湖农场企业化经营的组织结构、潘家湾镇的综合治理改革以及受到县级财政专项支持等外部要素是造成农地整理管护绩效差异的主要原因。研究结论验证了农地整理建后管护SCP分析框架的有效性,为提升农地整理管护绩效提供了理论依据。 相似文献