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Challenges of Implementing Participatory Irrigation Management for Food Security in semi-arid areas of Tanzania

Journal of Agricultural Science and Technology(B) 2015年第5期5卷 329-335页

作者： Pilly Joseph Kagosi Tanzania Forestry Research Institute P. O. Box 1854 Morogoro Tanzania

Participatory irrigation management （PIM） is theoretically assumed to reduce poverty significantly, but its practical experience and challenges are yet researched and documented in Tanzania. The study aimed at assessing challenges observed during implementation of PIM approach for food security in semi-arid areas of Tanzania. Data were collected through questionnaire, participatory rapid appraisal （PRA） tools, key informants interview, Focus Group Discussion （FGD）, observation and literature review. Data collected from questionnaire were analyzed using SPSS. Data fi＇om other methods were analyzed using content analysis. The study revealed that PIM approach has contribution in improving food security at household level due to involvement of communities in water management activities and decision making, which enhanced availability of irrigation water and increased crop production. However, there were challenges observed during implementation of the approach, including the minimum participation of beneficiaries in decision making during planning and designing stages, which means that inadequate devolution of power among scheme owners, inadequate and lack of transparency on income expenditure in water utilization associations （WUAs）, water conflict among WUAs members, conflict between farmers and livestock keepers and conflict between WUAs and village government leaders regarding training opportunities and status. The rules and regulation of WUAs were not legally recognized by the national courts and few farmers who planted trees around water sources. However, it was realized that some of the mentioned challenges were rectified by farmers themselves and facilitated by government officials. The study recommends that the identified challenges need to be rectified for farmers to realize more on the importance of PIM approach as it was realized in other Asian countries.

关键词： Challenges ofPIM PIM food security semi-arid areas Tanzania.

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Species composition and diversity,and carbon stock in a dune ecosystem in the Horqin Sandy Land of northern China

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Journal of arid Land 2015年第1期7卷 82-93页

作者： FeiLong HU WenKai SHOU Bo LIU ZhiMin LIU Carlos A BUSSO State Key Laboratory of Forest and Soil Ecology Institute of Applied Ecology Chinese Academy of Sciences University of Chinese Academy of Sciences Agronomy Department National University of the South and CERZOS (CONICET)

In this study, we determined carbon allocation and carbon stocks in the plant-soil system of different dune ecosystems in northeastern China. We quantified the species composition, above and below-ground bio masses, and carbon stocks of three dune types （i.e. active dunes, semi-stabilized dunes and stabilized dunes） and their corresponding inter-dune lowlands （i.e. interdune lowlands of active dunes, interdune lowlands of semi-stabilized dunes and interdune lowlands of stabilized dunes） in the Horqin Sandy Land. The results showed that the succession series on interdune lowlands of the Horqin Sandy Land confirmed differences in species composition of the various dune types. Aboveground carbon （AGC） on the interdune lowlands of semi-stabilized dunes （33.04 g C/m2） was greater （P〈0.05） than that on the interdune lowlands of active dunes （10.73 g C/m2）. At the same time, the different dune types did not show any significant differences （/：〉〉0.05） in belowground plant carbon （BGC）. However, the percentage of plant BGC in interdune lowlands of active dunes （81.5%） was significantly higher （P〈0.05） than that in the interdune lowlands of semi-stabilized dunes （58.9%）. The predominant carbon pool in the study dune ecosystem was in the soil. It accounted for 95% to 99% of total carbon storage. Soil organic carbon （SOC） was at least 55% greater （P〈0.05） in the interdunes than in the dunes. Stabilized dunes showed at least a 37% greater （P〈0.05） SOC content than active dunes up to a 1-m soil depth. Meanwhile, SOC content of interdune lowlands of semi-stabilized dunes was greater （P〈0.05） than that of interdune lowlands of active dunes only up to a 20-cm soil depth. The dune ecosystem showed a great potential to store carbon when interdune lowlands of active dunes were conversed to interdune lowlands of semi-stabilized dunes, which stored up to twice as much carbon per unit volume as interdune lowlands of active dunes.

关键词： species diversity carbon storage sand dunes interdune lowlands semi-arid areas

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INITIATION AND DEVELOPMENT PROCESSES OF TUNNEL SYSTEMS IN THE HILLY LOESS REGION OF NORTHERN CHINA

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International Journal of Sediment Research 2006年第3期21卷 171-179页

作者： T. X. ZHU1 Dr., Department of Geography, University of Minnesota-Duluth, 10 University Dr., Duluth, MN 55812, U.S.A. Department of Geography University of Minnesota-Duluth MN 55812 United States

Tunnel systems in the hilly loess region of northern China are among the largest and most complicated in the world. Tunnel formation and development processes were investigated in the Yangdaogou catchment over the period of 1989 through 2002. Newly formed tunnels on the roads in the Wangjiagou watershed were also examined in detail during a single storm in 2002. Soil samples were taken from various locations of the tunnel systems in the Yangdaogou catchment for chemical and physical analyses. The controlling factors of tunnel formation are surface drainage conditions and soil materials. Rapid downward mechanical erosion by storm flows seems to be responsible for the original formation of inlets. All tunnels are found in loess and none was found in red Tertiary earth. Underground tunnel paths often develop right above an impeding layer, mainly resulting from mechanical erosion rather than chemical dissolution. New inlets develop in old tunnel systems in two major ways. One is roof collapses of an existing tunnel path and the other is the mechanical scouring action of storm flows. A tunnel system can expand upslope or downslope but the associated processes differ. Upslope expansion often starts with the formation of one or more inlets resulting from surface washes, followed by the development of an underground tunnel path. Downslope development of a tunnel system is characterized by uneven enlargement of tunnel paths. This study suggests that the key to control of tunnel development is reducing surface water entering a tunnel.

关键词： Piping Tunnel erosion semi-arid areas Gully erosion Loess Plateau

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Review of runoff forestry in Shanxi Province and sustainable development tactics of forestry

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Journal of Forestry Research 2000年第2期11卷 135-139页

作者：张新波邝立刚任建茹 Shanxi Academy of Forestry and Northern Research Institute of Forestry of China Taiyuan P. R. China Shanxi Forestry Extension Station Shanxi China

Through more than one month of investigation on runoff forestry in Luliang mountainous areas of Shanxi Province, the runoff forestry techniques were regarded as having a popularized value in arid and semi-arid areas. The development of runoff forestry in Shanxi Province was summarized and the sustainable development tactics was put forward.

关键词： semi-arid areas Runoff forestry Sustainable development Development tactics

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The causes of land landscape changes in semi-arid area of Northwest China: a case study of Yulin city

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Journal of Geographical Sciences 2006年第2期16卷 192-198页

作者： GUO Liying REN Zhiyuan LIU Yansui College of Tourism and Environmental Sciences Shaanxi Normal University Xi＇an 710062 China Institute of Geographic Sciences and Natural Resources Research CAS Beijing 100101 China

Rapid land landscape change has taken place in many arid and semi-arid regions such as the vulnerable ecological area over the last decade. In this paper, we quantified land landscape change of Yulin in this area between 1985 and 2000 using remote sensing and GIS. It was found that fallow landscape decreased by 125,148 hm^2 while grassland and woodland increased by 107,975 hm^2 and 17,157 hm^2, respectively. The major factors responsible for these changes are identified as the change in the government policy on preserving the environment, continued growth in mining, and urbanization. The efforts in restoring the deteriorated ecosystem have reaped certain benefits in reducing the spatial extent of sandy land through replacement by non-irrigated farmland, woodland and grassland. On the other hand, continued expansion of mining industry and urbanization has exerted adverse impacts on the land landscape. At present regional economic development conflicts directly with the protection of the natural environment. Such a conflict has caused the destruction to the land resources and fragmentation of the landscape accompanied by land desertification, the case is even serious in some localities.

关键词： land landscape patterns driving forces semi-arid areas Yulin city

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CONTRIBUTIONS OF TUNNEL EROSION TO SEDIMENT YIELD IN A semi-arid BASIN IN THE LOESS PLATEAU OF CHINA

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International Journal of Sediment Research 2000年第4期 440-444页

作者： T.X. ZHU, Q.G. CAI and S.H.LUK3 Dr., Department of Geography, University of Minnesota-Duluth, Duluth, MN55812, USA. Tel: 218-724-8480. Fax: 218-726-6386. Email: tzhu@d.umn.edu Researcher, Institute of Geography, Chinese Academy of Sciences, Beijing, 100

To evaluate the geomorphic significance of piping and tunnel erosion in basin sediment yield in semiarid areas, we conducted a field monitoring program in Yangdaogou, a subbasin in the hilly loess region in the Loess Plateau of China in 1989 and 1990. Six tunnel systems were monitored through fifteen flow events. Overall, 57% of total basin sediment was routed through tunnel systems and net tunnel erosion accounted for about 25% of total sediment production of the basin. This study suggests that tunnel erosion can be highly significant in basin sediment delivery and hillslope development in send-arid areas.

关键词： Tunnel erosion Loess Plateau semi-arid areas

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