Monitoring land use/land cover change impacts on soils in data scarce environments: a case of south-central Ethiopia

To monitor land-use/land-cover (LULC) change and assess its impact on the soil property, the availability of benchmark data is indispensable, which is hardly available in the intensively cultivated regions of developing countries. Our study attempts to solve this problem by generating a benchmark soil data through the development of modified spatial analogue (MSA) method in the context of the Upper Dijo River catchment, south-central Ethiopia. The magnitude and patterns of LULC changes were extracted from air photos and satellite imageries, along with the acquisition of soil samples from the reference and target sites through ground survey. Analysis of digital image processing shows significant LULC changes in a period that spanned three decades. The impact of LULC change on soil quality was assessed by comparing the soil physico-chemical properties sampled from the reference and target sites. The result shows a decline in total nitrogen, organic matter, available potassium and pH levels in soils collected from target sites, which conforms to results reported by studies conducted in data-rich environment. With careful validation, MSA could be useful for monitoring soil property changes in data-scarce environment and generate soil-related parameters for agro-ecological models.     

Land-use choices: the case of conservation reserve program (CRP) re-enrollment in Kansas,USA

Among the important alternatives for land conservation is the US Conservation Reserve Program (CRP) that celebrated its 30th anniversary in 2015. This paper explores how landowners decide on alternative land-use choices made available by the expiration of CRP contracts in Kansas. The study uses survey data and multinomial Logit models to predict land-use choices. Two models were tested. The first model does not incorporate variables concerning farmer perceptions and attitudes about land-use choices, while the second model does. The results show that CRP re-enrollment depends on factors, such as years of experience in cropping and percent of cropland irrigated. However, when perception variables are added, the models become more robust in explaining other land choice alternatives. The results suggest that as the perception of unfairness of more inflexible environmental policy rises, these farmers may be more likely to re-enroll their marginal land in the CRP program.     

Land-use planning via enhanced multi-objective evolutionary algorithms: optimizing the land value of major Greenfield initiatives

The successful implementation of major development initiatives relies on the sound allocation of land uses against critical design criteria and constraints. The discovery of optimum development plans introduces severe complexities in formulating and solving the underlying multi-objective optimization problem. Moreover, in the presence of conflicting planning criteria decision-makers should be provided with a set of alterative-yet-optimum solutions that uniformly cover the spectrum of feasible maps. The introduction of sophisticated optimization algorithms addresses this challenge by pursuing a complete approximation of the Pareto front containing all prominent spatial allocations. This study demonstrates the effectiveness of a new evolutionary algorithm (UDT-MOEA) against the results of an established multi-objective genetic algorithm (NSGA-II) when applied on a major greenfield initiative against the optimum location(s), size and shape of three new land uses. Each algorithm performs best in different areas of the feasible objective space, providing planning alternatives with distinct characteristics.     

The impacts of warfare and armed conflict on land systems

ABSTRACT

Land-use decisions can change abruptly in response to shocks, and warfare and armed conflicts are among the most drastic and globally frequent shocks. Yet, our understanding of where armed conflict affects land systems, how land-use patterns are impacted, and how far-reaching and persistent these changes are, is partial. We used a spatially detailed dataset on armed conflict and a literature review to explore these questions. A number of key insights emerged from our study: (1) warfare and armed conflict affect land systems mainly in more densely populated areas, regardless of the dominating land use; (2) warfare and armed conflict can impact land systems in major ways, but these effects are diverse and not unidirectional; (3) warfare and armed conflict primarily affects land systems locally, but can forge telecouplings; and (4) although the impact of warfare and armed conflict is often immediate, it can instigate long-lasting land-use legacies.     

化学氧呼吸器的现状与发展趋势

随着人类社会的发展进步,对生产安全和应急救生用呼吸器的需求越来越旺盛,化学氧呼吸器已经成为重要的研究方向。介绍了化学氧呼吸器的工作原理和发展历程以及技术现状,分析比较了化学氧呼吸器的优缺点。在此基础上指出,优化产氧装置、开发高效冷却技术、降低整体体积和重量、制定技术标准和开发检测技术是化学氧呼吸器研究开发重要而又迫切的任务。     

Pollution prevention for sustainable development: the land-use question

The central argument of the paper is that effective pollution prevention can be achieved only by integrated land-use planning which offers the broad framework for co-ordinating technological and non-technological means to achieve sustainable development. The paper first reviews the role of land-use in preventing or contributing to pollution over time, focusing especially on contemporary efforts to promote environmental protection through land-use planning and management. The relationship between land-use, pollution and sustainable development is analysed by examining the most important types of land-use-related problems, discussing their causes and identifying a number of land-use-related constraints to sustainable development. Finally, a land-use planning and policy framework approach to pollution prevention for sustainable development is outlined which emphasizes the need for integrated analysis of pollution problems and adoption of comprehensive approaches to their solution. Scientific, spatial, temporal and policy issues are addressed in the context of the proposed approach.     

Effects of land use on water quality of two high-altitude lakes and catchments in Yunnan Province,China

SUMMARY

Reclaiming farmland from lakes in China in the 1950s damaged the water quality of many lakes. Tremendous efforts have been made since the late 1990s to restore vegetation around the damaged lakes. This paper examines water quality of Fuxian and Qilu Lakes and land-use characteristics within the two catchments in the high-altitude area of Yunnan Province, China. Landsat TM data acquired in 1989, 1994, 1999 and 2005 were used to extract land use and land cover (LULC) information. Measurements of five water quality indices (WQIs), BOD, COD, pH, TN and TP, for the same period of time were examined. The results showed that the area of residential and forest/shrub increased, whereas that of cropland and barren land decreased from 1989 to 2005 in both catchments. Qilu Lake was much more polluted than Fuxian Lake, and pollution worsened over time for both lakes. The differences in water quality between the two lakes were caused by differences in LULC composition and continued degradation in water quality was caused by intensive farming and urban sprawl. Unless the landscape is converted back to its pre-1950 composition and structure, water quality in both lakes cannot be significantly improved and will continue to threaten sustainable development in the region.     

Evaluation of the sustainable land use status of the North China Plain

The North China Plain is one of the most important production areas for wheat and maize in China, and also has the densest agricultural population in China. How to use and develop the limited land resources reasonably, and improve and protect them, have become issues of major concern. This paper is based on sustainability theory, reviewing the fundamental principles of sustainability, and developing an index system with which to evaluate the sustainability status of land use. We also use this method to evaluate the land-use status of the North China Plain and to analyze current factors affecting sustainable land use in this area. In addition, we propose a specific method for evaluating sustainable land use.     

高炉煤粉喷吹站消防水系统设计

介绍了钢铁行业的高炉煤粉喷吹站消防水系统总的设计原则、设计方法,并针对某钢铁联合企业两座1 780 m3高炉合建的煤粉喷吹站消防水系统设计的工程实例,详细论述了高炉煤粉喷吹站消防水系统的选择方法、组成部分、主要参数的确定方法及控制方法。同时结合工程实践,对高炉煤粉喷吹站消防水系统设计中常遇到的一些问题提出了合理建议。     

滑脱流动影响的低渗储层甲烷运移采出规律研究

为了达到低渗储层甲烷抽采过程甲烷采井优化设计和产能准确预测的目的,基于现场测井数据,采用非线性流体数值计算方法,以柳林煤层甲烷试验采区为例,对滑脱流动影响的煤层甲烷采场压力非线性分布和产能预测进行研究。数值计算结果表明:低渗储层甲烷运移采出受气体滑脱流动影响显著,考虑滑脱流动影响时,采场压力衰减区域变大,气体速率变快;对比测井产能历史拟合数据发现,计算所得的滑脱流动影响的产能预测值更加准确。由计算结果验证了单井开采具有采场压力影响范围较小,产能较低等缺点,并得出五采出四压裂的布井方式是既能够准确预测产能又能够更好避免井间干扰效应的最优布井方式。