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81.
Oluyede Clifford Ajayi Festus K. Akinnifesi Gudeta Sileshi Adeola O. Ajayi 《Natural resources forum》2009,33(2):111-122
In most of sub‐Saharan Africa, where the agricultural sector experiences dismal performance and is characterized by a gloomy picture, the cotton sub‐sector in Côte d’Ivoire is often mentioned as a “success story” given the spectacular rise in the quantity of cotton production and the profile of the crop within the farming system. What are the historical and political antecedents of the development of cotton and the factors responsible for the feat accomplished in the midst of general failures in the same continent? To what extent can cotton be regarded as a “success story” and, what lessons can be drawn for agricultural development strategies based on the Ivorian case study? This paper traces the historical and socio‐political background of cotton development in Côte d’Ivoire and identifies key policy and institutional interventions that have influenced the rise of cotton production and its emergence as the dominant crop in the farming systems of the country. Four stages in Ivorian cotton development are identified: planning, take off, crisis and the renaissance phases. The study demonstrates how a combination of good planning, technological advancement and appropriate policy and institutional conditions have contributed significantly to the rise of cotton production and its influence on the agricultural economy of northern Côte d’Ivoire. The study also highlights how the sustainability of agricultural development has been impacted by domestic and international policies and political events over which smallholder farm families have little control, and can at best only respond to. Important questions about cotton development in Côte d'Ivoire are raised that need to be answered before the program can be categorized conclusively as a success story. The study shows that there are no quick fixes to agricultural development in the sub‐region. Rather, good planning and putting the necessary building blocks in place are important prerequisites. It is recommended that agricultural development efforts in the continent take cognizance of the complexity of the sector and address the inter‐relationships that exist among the technical, policy, market and institutional factors that combine individually and collectively to influence African agriculture. 相似文献
82.
Indicators of visual scale as predictors of landscape preference; a comparison between groups 总被引:1,自引:0,他引:1
Tveit MS 《Journal of environmental management》2009,90(9):2882-2888
Landscape change alters the visual scale of agricultural landscapes, as production units get larger and strips of taller vegetation are removed between smaller units. Visual scale, defined as the perceptual units reflecting the experience of landscape rooms, visibility and openness, is considered a key factor shaping landscape preference. The visual expression of landscapes affects people in many ways; aesthetic appreciation, health and well being. In order to understand how landscape changes alter the visual scale of landscapes, and hence its effect on human beings, it is important to establish efficient and practical ways of measuring visual scale and its relation to landscape preferences. This paper presents an empirical test of the ability to predict landscape preference of two photo-based indicators of visual scale; percentage open land in the view and size of landscape rooms. A preference survey was conducted with two groups of respondents; a student group from the Norwegian University of Life Sciences (UMB) and a public group. The student group was chosen to represent future landscape professionals. Photos of landscapes varying in the expression of visual scale were shown to survey respondents, who were asked to give scores according to how much they liked the landscapes. Both indicators were found to be predictors of preference for the student group, but not for the public group. The results demonstrate that student preferences do not reflect the landscape preferences of the wider public. The different appreciation of visual scale in the landscape of future landscape professionals and the public implies that experts wanting to reflect preferences of the wider public should be cautious when evaluating the visual impact of landscape change. 相似文献
83.
Roger B. Hammer Susan I. Stewart Todd J. Hawbaker Volker C. Radeloff 《Journal of environmental management》2009
Rural, forested areas throughout the United States are experiencing strong housing growth with potentially detrimental impacts on the environment. In this paper, we quantify housing growth in Northern Wisconsin over the last sixty years to determine if growth rates were higher near public lands, which may represent an important recreational amenity. We used data from the U.S. Census to produce decadal housing density estimates, “backcasts,” from 1940 to 2000 for northern Wisconsin to examine “rural sprawl” in northern Wisconsin and its relationship to forested areas and public lands. We integrated housing density estimates with the 1992/1993 National Land Cover Dataset to examine the relationship between rural sprawl and land cover, especially forests. Between 1940 and 2000, private land with <2 housing units/km2 decreased from 47% to 21% of the total landscape. Most importantly, housing growth was concentrated along the boundaries of public lands. In 14 of the 19 counties that we studied, housing growth rates within 1 km of a public land boundary exceeded growth rates in the remainder of the county, and three of the five counties that did not exhibit this pattern, were the ones with the least amount of public land. Future growth can be expected in areas with abundant natural amenities, highlighting the critical need for additional research and effective natural resource management and regional planning to address these challenges. 相似文献
84.
绿色发展是乡村振兴的必由之路.通过对南京市D村的实地调查,发现政府主导的转型模式在推动村庄绿色发展的同时,存在村庄内生动力不足、内部利益分化以及产业市场竞争力较弱等风险,制约着村庄可持续发展.基于此提出,政府在开发与建设过程中要充分保障村民主体性的发挥,同时注重提高产业的市场竞争力. 相似文献
85.
The Spatio-Temporal Dynamic Pattern of Rural Residential Land in China in the 1990s Using Landsat TM Images and GIS 总被引:2,自引:0,他引:2
Through interpreting Landsat TM images, this study analyzes the spatial distribution of rural settlements in China in 2000.
It calculates rural residential land percentage for every 1-km2 cell. The entire country is divided into 33 regions to investigate the spatio-temporal dynamic patterns of rural residential
land during the 1990s. According to the remote sensing survey, the rural residential land increased by 7.88 × 105 ha in the 1990s. The increment of rural residential land was 0.55 million ha in 1990–1995 and 0.23 million ha in 1995–2000.
In 1990–1995, rural residential land increased dramatically in the eastern regions such as the Yangtze River Delta, Pearl
River Delta, and North China Plain, accounting for 80.80% of the national growth; the expansion in the western regions was
much more moderate. In 1995–2000, the expansion of rural residential land in eastern regions slowed, accounting for only 58.54%
of the increase at the national level, whereas the expansion in the western regions accelerated. Rapid rural residential development
resulted from increasing home construction and the limited control on rural land. The great regional disparity reflected the
regional economic development and land-use policy change. Our finding shows that nearly 60% of the rural residential area
came from cropland. 相似文献
86.
87.
88.
通过设置三级串联人工生态湿地,对农村生活污水的处理效果进行监测和研究。结果表明,三级串联人工生态湿地对农村生活污水效果较好,出水COD、SS、氨氮、TN、TP平均值分别为12mg/L、13mg/L、1.24mg/L、3.32mg/L、0.43mg/L,平均削减率分别为58.11%、57.13%、82.87%、65.77%、59.92%,出水水质达到《城市污水处理厂污染物排放标准》(GB18918-2002)的二级标准。 相似文献
89.
90.