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The Impacts and Causes of Land Fragmentation on Farm Productivity: Case Review of East African Countries
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作者 Joseph Mayindo Mayele Jacob B. Kolleh Joel Emmanuel Saburi 《Open Journal of Ecology》 2024年第5期455-482,共28页
This report provides an overall assessment of land fragmentation problems in East Africa. Many parts of East Africa have become highly fragmented, putting development systems and activities in these areas at risk of c... This report provides an overall assessment of land fragmentation problems in East Africa. Many parts of East Africa have become highly fragmented, putting development systems and activities in these areas at risk of complete collapse. Land fragmentation occurs when land gets converted for agriculture, industrialization, or urbanization, invaded by non-local plants, or enclosed for individual use and by subdividing farmlands into subsequent smaller units called parcels with varying average farm sizes. Fragmentation results from inappropriate agricultural development processes and ineffective land use planning that fails to recognize how farmland is used, and the importance of its interconnected areas. Insecurity of tenure and resource rights are key factors in making this possible. Land fragmentation is one of the key reasons why the ability of most resources in East Africa becomes scarcer, and those remaining become “privatized” by more powerful community members—keen to maintain their access to them. Such individualistic attitudes are new and disadvantage the poorest even further by affecting the traditional customary safety nets and agricultural outputs. Neither the government nor customary governance systems effectively protect resource access for the poorest. This review summary report identifies the key causes, measures, and implications, government interventions, and the common remedies to land fragmentation problems in the East African Countries of Kenya, Uganda, Rwanda, and Tanzania including neighboring Ethiopia, and the Sudan. The findings indicated from 2005 to 2015, the population kept increasing for all the named countries in East Africa with Rwanda and Uganda having a substantial increase in population density. The study review further explores the trend in the performance of agriculture by average farm sizes within the intervals of five years by highlighting their strong linkages and found that the average farm size has declined drastically, especially for Kenya. This can only mean that small farms kept becoming smaller and smaller and that there were more small-scale farmers. The results further depicted that the major and commonly cultivated food crops among the East African countries include maize, sorghum, rice, cassava, sweet potatoes, bananas, Irish potatoes, beans, peas, etc., with maize yields (Mt/ha) in 2003 for Uganda being the highest (1.79 Mt/ha) and the lowest in Rwanda (0.77 Mt/ha) respectively. Therefore, from the review results, recommendations are being made as to how the negative impacts of land fragmentation on agricultural productivity can be reduced or mitigated. One way is by community sensitization and awareness about the importance of land consolidation and its proposition on farm productivity. 展开更多
关键词 land fragmentation land Consolidation Farm Productivity INDUSTRIALIZATION Impacts CAUSES Average Farm Size Population East Africa
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Design of a spatial sampling scheme considering the spatial autocorrelation of crop acreage included in the sampling units 被引量:9
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作者 WANG Di ZHOU Qing-bo +1 位作者 YANG Peng CHEN Zhong-xin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第9期2096-2106,共11页
Information on crop acreage is important for formulating national food polices and economic planning. Spatial sampling, a combination of traditional sampling methods and remote sensing and geographic information syst... Information on crop acreage is important for formulating national food polices and economic planning. Spatial sampling, a combination of traditional sampling methods and remote sensing and geographic information system (GIS) technology, provides an efficient way to estimate crop acreage at the regional scale. Traditional sampling methods require that the sampling units should be independent of each other, but in practice there is often spatial autocorrelation among crop acreage contained in the sampling units. In this study, using Dehui County in Jilin Province, China, as the study area, we used a thematic crop map derived from Systeme Probatoire d'Observation de la Terre (SPOT-5) imagery, cultivated land plots and digital elevation model data to explore the spatial autocorrelation characteristics among maize and rice acreage included in sampling units of different sizes, and analyzed the effects of different stratification criteria on the level of spatial autocorrelation of the two crop acreages within the sampling units. Moran's/, a global spatial autocorrelation index, was used to evaluate the spatial autocorrelation among the two crop acreages in this study. The results showed that although the spatial autocorrelation level among maize and rice acreages within the sampling units generally decreased with increasing sampling unit size, there was still a significant spatial autocorrelation among the two crop acreages included in the sampling units (Moran's / varied from 0.49 to 0.89), irrespective of the sampling unit size. When the sampling unit size was less than 3000 m, the stratification design that used crop planting intensity (CPI) as the stratification criterion, with a stratum number of 5 and a stratum interval of 20% decreased the spatial autocorrelation level to almost zero for the maize and rice area included in sampling units within each stratum. Therefore, the traditional sampling methods can be used to estimate the two crop acreages. Compared with CPI, there was still a strong spatial correlation among the two crop acreages included in the sampling units belonging to each stratum when cultivated land fragmentation and ground slope were used as stratification criterion. As far as the selection of stratification criteria and sampling unit size is concerned, this study provides a basis for formulating a reasonable spatial sampling scheme to estimate crop acreage. 展开更多
关键词 crop acreage spatial autocorrelation sampling unit planting intensity cultivated land fragmentation ground slope
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Spatial Structure Adjustment Strategies of the Coal Resource-Based Cities during the Mature Period: A Case Study of Pingdingshan
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作者 YU Yang ZHAO Pan QIAN Yuexi 《Journal of Landscape Research》 2017年第4期22-28,共7页
Coal cities are the main part of the resource-based cities in China, and the benign development of coal cities' spatial structure has a direct impact on these cities' future economic and social development, as... Coal cities are the main part of the resource-based cities in China, and the benign development of coal cities' spatial structure has a direct impact on these cities' future economic and social development, as well as the urban residents' welfare. Land use fragmentation is the most typical morphological characteristic of the coal city's spatial structure development. In this paper, Pingdingshan City of Henan Province in China is taken as an example. Through empirical analysis, the urban spatial structure development processes of a typical coal resource-based city in its mature period are illustrated, and the formation reasons and potential mechanism behind coal city land use fragmentation are explored, and the measurement method of land use fragmentation degree of the coal city is put forward. On the above basis, the appropriate adjustment strategies and methods aimed at the coal city spatial structure are found out and given. This study is a good guideline and reference for the spatial structure planning and land use planning of the coal city during the mature and declining period, which is of great help to the sustainable development and industrial structure transformation of the coal city. It also has certain reference significance for the coal city in the growth period. 展开更多
关键词 Coal city Spatial structure land use fragmentation Transportation infrastructure
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Assessment of multifunctional landscapes dynamics in the mountainous basin of the Mo River (Togo, West Africa) 被引量:1
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作者 DIWEDIGA Badabate AGODZO Sampson +1 位作者 WALA Kperkouma LE Quang Bao 《Journal of Geographical Sciences》 SCIE CSCD 2017年第5期579-605,共27页
In this study, historical landscape dynamics were investigated to(i) map the land use/cover types for the years 1972, 1987, 2000 and 2014;(ii) determine the types and processes of landscape dynamics; and(iii) as... In this study, historical landscape dynamics were investigated to(i) map the land use/cover types for the years 1972, 1987, 2000 and 2014;(ii) determine the types and processes of landscape dynamics; and(iii) assess the landscape fragmentation and habitat loss over time. Supervised classification of multi-temporal Landsat images was used through a pixel-based approach. Post–classification methods included systematic and random change detection, trajectories analysis and landscape fragmentation assessment. The overall accuracies(and Kappa statistics) were of 68.86%(0.63), 91.32%(0.79), 90.66%(0.88) and 91.88%(0.89) for 1972, 1987, 2000 and 2014, respectively. The spatio-temporal analyses indicated that forests, woodlands and savannahs dominated the landscapes during the four dates, though constant areal decreases were observed. The most important dynamic process was the decline of woodlands with an average annual net loss rate of –2%. Meanwhile, the most important land transformation occurred during the transition 2000–2014, due to anthropogenic pressures. Though the most important loss of vegetation greenness occurred in the unprotected areas, the overall analyses of change indicated a declining trend of land cover quality and an increasing landscape fragmentation. Sustainable conservation strategies should be promoted while focusing restoration attention on degraded lands and fragmented ecosystems in order to support rural livelihood and biodiversity conservation. 展开更多
关键词 land cover dynamics spatio-temporal patterns swap change landscape fragmentation protected areas Mo River Basin TOGO
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中国耕地细碎分异对种植业地理集聚格局的影响 被引量:5
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作者 徐伟义 金晓斌 +1 位作者 刘晶 周寅康 《Journal of Geographical Sciences》 SCIE CSCD 2020年第10期1571-1589,共19页
Systematically revealing the impact of cultivated land fragmentation(CLF)on the geographical agglomeration pattern of agricultural specialization(AS)has positive significance for national agricultural production manag... Systematically revealing the impact of cultivated land fragmentation(CLF)on the geographical agglomeration pattern of agricultural specialization(AS)has positive significance for national agricultural production management.Based on the data of the second national land survey and agricultural production,this study has explored the impact of CLF on spatial heterogeneity of agricultural agglomeration in China by comprehensively using the Theil index,ordinary least square model and geographically weighted regression.Results showed that:(1)the regional differentiation of the CLF in China is obvious,and the cultivated land fragmentation index is generally characterized by increasing pattern from northwest to southeast.(2)Spatially,the development level of AS in China has formed three high-value clusters in the Northeast China Plain,the Qinghai-Tibet Plateau,and the middle of the Middle-lower Yangtze Plain;and the low-value contiguous areas centered on the Yunnan-Guizhou Plateau and the Sichuan Basin and surrounding regions,with significant spatial differences.The contribution of grain crops,economic crops,and vegetables and melon to the level of AS was 74.63%,9.09%,and 16.28%,respectively,and the pattern of agricultural geographical aggregation dominated by grain crops has primarily taken in shape.(3)CLF is significantly negatively correlated with AS,and every 1%increase in the degree of CLF will result in a decrease of about 0.2%in AS.However,the impact of CLF on the geographic agglomeration of different crop categories or groups varies significantly.Among them,CLF has a prominent impact on the specialization level of grain crops and vegetables and melon.Each 1%increase in the CLF will reduce the specialization level of grain crops by 0.38%,and increase the level of vegetables and melon by about 0.22%.(4)According to the landscape characteristics of cultivated land,the degree of spatial division and agglomeration of cultivated land patches have a significant impact on the formation of geographical agglomerationpattern of AS,and the intensity and direction of influence show significant regional differentiation,while the patch size has no significant impact. 展开更多
关键词 cultivated land fragmentation agricultural specialization regional differentiation impact
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