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land-use and land-cover affect inland fish catch in two rivers of Central Africa

Water Biology and Security 2022年第4期1卷 51-60页

作者： Leandro Castello Gifty Anane-Taabeah Attu Anthony Aliebe Nelly Ornelle Onana Ateba Sandrine Jueya Felipe Carvalho Amy Ickowitz Emmanuel A.Frimpong department of Fish&Wildlife Conservation Virginia Polytechnic Institute and State UniversityBlacksburgVAUnited States department of Fisheries and Watershed Management Kwame Nkrumah University of Science and TechnologyKumasiGhana Farmerline Limited KumasiGhana department of Parasitology and Ecology University of Yaounde 1YaoundeCameroon Faculty of Sciences University of NgaoundereNgaoundereCameroon Center for International Forestry Research BogorIndonesia

land-cover change can affect inland fisheries,which underpin food security of millions of people *** of forests from very large floodplains has been found to decrease fish catch via loss of feeding and nursery habitat for ***,it is unknown if similar effects occur in smaller rivers with limited floodplain *** is also known about the mechanisms by which land-cover changes affect inland fish ***,we assessed land-use and land-cover(LULC)effects on fish catch,diet,and condition at sites in two medium-sized rivers of Cameroon,in Central *** found that LULC explained 30%of the variation in fish catch,with the catch of five species being positively,and of two species being negatively,related to floodplain *** niche breadth of fish diets was higher in the river surrounded by forests than in the river surrounded by agricultural ***,contrary to expectations,condition of the fish,as indicated by occurrence of diseases or deformities,eroded fins,lesions or tumors,was not related to *** results support the notions that floodplain forests support fish populations in rivers with limited floodplain areas in ways similar to that of rivers with large floodplains,and that LULC affects fish populations via changes in fish diets and instream habitat features(i.e.,riparian canopy closure,water clarity,substrate heterogeneity,and habitat volume).These effects imply that prevailing changes in LULC threaten the food and livelihood security services provided by inland fisheries,highlighting the importance of policies that maintain native vegetation along riverbanks and in floodplain areas.

关键词： Agriculture Diet Fish traits Food security LULC

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Application of revised universal loss equation model

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Chinese Journal Of Geochemistry 2006年第B8期25卷 210-211页

作者： Samira El Bahi Mohamed El Wartitil Mohamed Yassin department of Geology Faculty of Sciences. Mohammed V University B.P.1014 Rabat Morocco CNRF Avenue Omar Ibn Al Khattab Rabat Morocco

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Analysis of the Fruit Value Chain of Two Priority Food Woody Species of Central Southern Niger, West Africa

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Open Journal of Forestry 2020年第3期10卷 277-292页

作者： Massaoudou Moussa Tougiani Abasse Habou Rabiou Moussa Aboubacar Larwanou Mahamane department of Natural Resources Management National Institute for Agricultural Research (INRAN) Maradi Niger University of Diffa Diffa Niger International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) Niamey Niger

Non-timber forest products provide important socio-economic services to different village and urban communities in West Africa. However, little is known about the links between the different actors and their contribution to the local or national economy. This study was conducted in central southern Niger and aimed to 1) identify and map the main actors in the value chain of Ziziphus mauritiana and Balanites aegyptiaca fruits;and 2) analyse the silvicultural and socio-economic aspects of fruit exploitation of these two species. Socio-economic surveys were conducted in four big villages in two main agroecological zones. Fruit exploitation of these two species affected 3044 people, with estimated 39 tonnes of Z. mauritiana and 27 tonnes of B. aegyptiaca fruit collected in 2017. The surveys revealed that the main actors were women (62.05%), constituting the primary core of the actors of the value chain. Exploitation was mainly conducted in forests (68.6%) or on farms (15.4%) with no restrictions to access. Marketing of Z. mauritiana concerned fresh fruit (68.8%) and fruit processed into biscuits (82.14%), and that of B. aegyptiaca involved fruit (38.5%) and oil extracted from seeds (38.7%);the net margin was estimated at 71.71% ± 21.59% for the first species and 50.31% ± 47.99% for the second. The income was mainly used for the needs of farmers’ households. Links have been identified where consumers and processors supply seeds, after extracting the fruit pulp, to nurserymen for the production of plants for the villages or farms. This study reveals an important potential and opportunity for job creation and improved food and nutritional status of the vulnerable strata of rural communities in Niger. Improving the links between the various actors will establish a more sustainable promotion of the fruits of these two species.

关键词： Balanites aegyptiaca Ziziphus mauritiana Value Chain Non-Timber Forest Products Food Security Income West Africa

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Sheep Production Systems and Breeding Practices for Selected Zones of Tigray, Northern Ethiopia

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Open Journal of Animal Sciences 2019年第1期9卷 135-150页

作者： Kiflay Welday Mengistu Urge Solomon Abegaz department of Animal and Range Sciences Jigjiga University Jigjiga Ethiopia Schools of Animal and Range Sciences Haramaya University Dire Dawa Ethiopia Ethiopian Institute of Agricultural Research (EIAR) Addis Ababa Ethiopia

A study was undertaken to identify the production system, breeding practices and major production constraints of common Tigray highland sheep in 16 rural kebelles from eight districts of Tigray Regional State. A total of 480 households (30 households for each rural kebelle) were selected purposively to collect data through personal observations and a detailed structured questionnaire. Mixed crop-livestock production system was the dominant farming system in all the study districts. The farmers kept a variety of livestock species including sheep, goats, cattle, chickens horse, donkeys and bee colony. Sheep, principally as source of income, meat for home consumption, production of manure and for socio cultural purposes, are commonly herded with other species in the open grazing fields by young boys in a family. Mating was generally uncontrolled. Body size, growth rate and adaptability were the major traits in selecting rams, whereas ewes were selected based on body size, twining ability and lambing interval. Majority of sheep across all districts are housed in structures known as Gebella which is built from stone and mud wall and tree/corrugated iron sheet roofing separated from the main family house. The major constraints hampering sheep production in the study areas were feed shortage (0.25), lack of capital (0.24), insufficient veterinary services (0.2), limited grazing land (0.2), water scarcity (0.06) and predators (0.05) with index value indicated in parenthesis. In order to improve the productivity of sheep, it is important to involve farmers and other stockholders in addressing these constraints and designing breed improvement interventions, considering the overall farming and breeding practice of smallholders.

关键词： Husbandry Practice Production Constraints Sheep production System

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与市场不一致的土地政策系统导致的中国结构性扭曲之负面影响(英文)

与市场不一致的土地政策系统导致的中国结构性扭曲之负面影响(英...

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北京论坛（2009）文明的和谐与共同繁荣——危机的挑战、反思与和谐发展

作者：文贯中 department of Economics Trinity College The Shanghai University of Finance and Economics

China's current growth model,relying mainly on external demand,will encounter increasing resistance from outside in the *** the purpose of reducing global trade imbalance and the resultant global monetary imbalance,and but for its own smoother growth,China should try harder to raise its internal demand. However,one of the main institutional constraints in lifting its internal demand comes from its existing land system that is seriously incompatible with market *** has caused serious structural distortions in both farming and non- farming sectors,such as aggravating the three agrarian issues,retarding urbanization,delaying service sector,creating pressure for over-revaluation of its currency,slowing absorption of its huge rural surplus labor into urban sector, depriving farmers of financial services,worsening income distribution across regions in general and widening rural-urban disparity in *** addition, this land system,in the name of speeding land takings,creates legal and moral issues. Therefore,if China finds a way to thoroughly reform this outdated land system together with its Hukou system to make labor and land allocation in a more market-compatible way,it can greatly boost its internal demand at a time when the decline in the growth of its external demand is expected to be a long-term trend.

关键词：结构性

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Floristic diversity and carbon stocks in the periphery of Deng–Deng National Park,Eastern Cameroon

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Journal of Forestry Research 2020年第3期31卷 989-1003页

作者： Louis Paul Roger Kabelong Banoho Louis Zapfack Robert Bertrand Weladji Cedric Chimi Djomo Melanie Chichi Nyako Yannick Enock Bocko Damien Marie Essono Julliete Mancho Nasang Nade`ge Madountsap Tagnang Charles Innocent Memvi Abessolo Kenneth Roger Mvondo Sakouma Farikou Mamadou Souahibou Florence Jeanne Sarah Palla Tonga Ketchatang Peguy Remi Jiagho Thierry Loic Kenmou Ulrich Arnaud Choumele Kana Jumo Boris Armel Anyam Yi Andjik Roger Bruno Tabue Mbobda department of Plant Biology Faculty of ScienceUniversity of Yaounde IBP 812 YaoundeCameroon IUCN World Commission On Protected Areas Co-Vice Chair Commission Mondiale des Aires Protegees-Afrique Centrale(CMAP-UICN)GlandSwitzerland Organisation pour la Conservation et le Developpement(OCD) BP 33323 YaoundeCameroun department of Biology Concordia University7141 Sherbrooke St.W.MontrealMontrealQC H4B 1R6Canada Institute of Agricultural Research for Development(IRAD) PO.BOX 2123YaoundeCameroon Laboratoire de Botanique et Ecologie Facultedes Sciences et TechniquesUniversiteMarien NgouabiBrazzavilleCongo Ministry of Forestry and Wildlife BP 34430 YaoundeCameroon Programme National de Developpement Participatif(PNDP) YaoundeCameroun Observatoire des Forets du Bassin du Congo(OFAC) BP 20818 YaoundeCameroun Fokabs International PO BOX 14097YaoundeCameroon International Union for Conservation of Nature Programme CamerounBP:5506 YaoundeCameroun Secretariat Technique REDD BP 320 YaoundeCameroun

Carbon is continuously being removed from the atmosphere by photosynthesis and stored in carbon pools(live,dead,and soil carbon)of forest ***,carbon stock in dead wood and of trees with diameters at breast height(dbh)between 5 and 10 cm is often not considered in many studies carried out in the Congo Basin *** relationship between tree diversity,life-forms and carbon stocks has received little *** study was carried out on the outskirts of Deng Deng National Park(DDNP)to determine tree diversity(dominant families,species richness and Shannon index),assess carbon stocks in the five carbon compartments(living tree,understory,fine roots,dead wood and litter)as well as to analyze the relationship between(1)carbon stocks and tree diversity;and,(2)between carbon stock and *** Shannon index of trees≥10 cm dbh ranged from 2.6 in riparian forest to 4.3 in secondary forest;and for the tree between 5 and 10 cm,it ranged to 1.56 in riparian forest to 3.68 in the secondary *** study site housed 16 species,7 genera and 3 families which are only found in trees of dbh between 5 and 10 *** average total carbon stock of the five compartments varied from 200.1 t ha-1 in forest residues to 439.1 t ha-1 in secondary *** wood carbon stock varied from 1.2 t ha-1 in riparian forests to 12.51t ha-1 in *** above ground carbon stocks for trees with diameter between 5 and 10 cm varied from 0.7 t ha-1 in young fallow fields to 5.02 t ha-1 in old secondary *** study reveals a low but positive correlation between species richness and total carbon stocks,as well as a significant positive relationship between life-forms and total carbon *** findings highlight the need for more data concerning carbon content of dead wood,carbon of trees≥5 cmforests

关键词： Deng Deng national park Carbon stocks land cover types Species diversity Dead wood

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Bridging mapping and simulation modelling in the ecosystem service assessments of boreal forests:effects of bioenergy production on carbon dynamics

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Forest Ecosystems 2021年第1期8卷 35-49页

作者： Anu Akujärvi Anna Repo Altti M.Akujärvi Jari Liski Finnish Environment Institute SYKE Biodiversity CentreLatokartanonkaari 11FI-00790 HelsinkiFinland University of Helsinki Department of Geosciences and GeographyP.O.Box 64FI-00014 HelsinkiFinland Natural Resources Institute Finland(Luke) P.O.Box 2FI-00791 HelsinkiFinland VTT Technical Research Centre of Finland LTD P.O.Box 1000FI-02044 VTT EspooFinland Finnish Meteorological Institute Climate System Research UnitP.O.Box 503FI-00101 HelsinkiFinland

Background:Increasing the use of forest harvest residues for bioenergy production reduces greenhouse emissions from the use of fossil ***,it may also reduce carbon stocks and habitats for deadwood dependent ***,simple tools for assessing the trade-offs of alternative management practices on forest dynamics and their services to people are *** objectives of this study were to combine mapping and simulation modelling to investigate the effects of forest management on ecosystem services related to carbon cycle in the case of bioenergy production;and to evaluate the suitability of this approach for assessing ecosystem services at the landscape *** level simulations of forest growth and carbon budget were combined with extensive multi-source forest inventory data across a southern boreal landscape in *** changes in the stand age class distribution over the study region were simulated to mimic variation in management ***:The mapping framework produced reasonable estimates of the effects of forest management on a set of key ecosystem service indicators:the annual carbon stocks and fluxes of forest biomass and soil,timber and energy-wood production and the coarse woody litter production over a simulation period 2012–*** harvesting,affecting the stand age class distribution,was a key driver of the carbon stock changes at a landscape *** forest harvest residues in the final felling caused carbon loss from litter and soil,particularly with combined aboveground residue and stump *** also reduced the annual coarse woody litter production,demonstrating negative impacts on deadwood abundance and,consequently,forest ***:The refined mapping framework was suitable for assessing ecosystem services at the landscape *** procedure contributes to bridging the gap between ecosystem service mapping and detailed simulation modelling in boreal *** allows for v

关键词： Carbon budget Ecosystem services Forest management Forest bioenergy landscape level Mapping Modelling

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Peri-urban Development:Discussion with land Use Zoning,Statutory Provision,and Issues inside Katahari rural Municipality,Nepal

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Journal of Geographical Research 2023年第1期6卷 1-16页

作者： Kedar Dahal Central department of Geography Tribhuvan UniversityKathmandu44618Nepal

The peri-urban area is a transitional zone between the city and its hinterlands characterized by mixed land use and intensive flows of resources,people,goods,and services from and to the city *** zones are generally misguided and haphazardly developed without a proper planning *** peri-urban area at present will be the urban area in the future;therefore,it needs planning intervention in its initial stage of ***,a peri-urban area of Biratnagar metropolitan city,is developing a spontaneous lack of land use ***,the Government of Nepal has encouraged the local government to implement land use plans in the provided framework,policy,and *** study,in this context,attempts to analyze and identify land use issues and potential zones for Katahari rural municipality that also supports planning urban development in the *** study is based on primary and secondary data and information supported by maps and *** is concluded that Katahari has been developed as a multi-function center adjoining the Biratnagar metropolitan city,and future expansion of the city will cover a wide range of rural *** postal highway that passes through it has attracted a wide range of urban ***,residential,commercial,and industrial are the main land use category at present and needs development control through providing land use zoning and related planning instruments through the increasing role of the stakeholder and the government agencies in the decision-making processes and implementation of spatial development frameworks to regulate peri-urban development in the area which will guide the future planning for liability,economic viability,social inclusion,and environmental sustainability in the ***-over development activities of Biratnagar,have increased the number of economic activities,population growth,and mixed-use development.

关键词： Peri-urban land use Urban expansion Spill-over development rural municipality Agriculture

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The Public Water Supply Protection Value of forests: A Watershed-Scale Ecosystem services Analysis Based upon Total Organic Carbon

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Open Journal of Ecology 2014年第9期4卷 517-531页

作者： Emile Elias David Laband Mark Dougherty Graeme Lockaby Puneet Srivastava Hugo Rodriguez Biosystems Engineering Auburn University Auburn USA Forestry and Wildlife Science department Auburn University Auburn USA School of Economics Georgia Institute of Technology Atlanta USA Tetra Tech Inc. Atlanta USA USDA-ARS Jornada Experimental Range New Mexico State University Las Cruces USA

We developed a cost-based methodology to assess the value of forested watersheds to improve water quality in public water supplies. The developed methodology is applicable to other source watersheds to determine ecosystem services for water quality. We assess the value of forest land for source water mitigation of total organic carbon (TOC) through the use of linked watershed and reservoir simulation models and cost-based valuation economics. Watershed modeling results indicated that expected urbanization will increase TOC loads to Converse Reservoir (Mobile, AL). Reservoir model results indicated that future median TOC concentrations increased by 1.1 mg·L-1 between 1992 and 2020 at the source water intake. Depending upon dynamic reservoir TOC concentrations, additional drinking water treatment with powdered activated carbon (PAC) often is necessary between May and October to comply with Safe Drinking Water Act regulations. The cost for additional treatment was calculated using minimum and maximum volume treated with simulated TOC concentrations at the source water intake. Daily simulated TOC concentrations for the base scenario using 1992 land cover (3% urban) were compared with simulated TOC concentrations following forest to urban land conversion predicted in the watershed by 2020 (22% urban). The daily cost for additional drinking water treatment with PAC was calculated if simulated TOC concentrations exceeded 2.7 mg·L-1. The mean increase in daily treatment costs between base and future scenarios ranged from $91 to $95 per km2 per day for forest land water purification ecosystem services.

关键词： Ecosystem services Water Quality Drinking Water Treatment Urbanization land Use Change

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Patterns of Changes to Woody Vegetation near Resettlement Sites in Semi-arid Northwestern Ethiopia

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Journal of Resources and Ecology 2018年第3期9卷 317-329页

作者： Mulubrhan Balehegn Kidane Hintsa Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China International Ecosystem Management Partnership United Nations Environment Programme Beijing 100101 China department of Animal Rangeland and Wildlife Sciences Mekelle University Mekelle Post Box 231 Ethiopia

Communal rangelands provide diverse ecosystem services to millions of pastoralists and agro-pastoralists. Resettling destitute communities into hitherto uninhabited communal rangelands and forests, a common practice throughout Sub-Saharan Africa, is a threat to the sustainable use of range and forest land resources. In order to understand the effect of resettlement on a semi-arid woodland in northwestern Ethiopia, satellite imagery of 23 resettlement villages taken over a period of fourteen years, and woody vegetation floristic data for three old resettlements, three new resettlements, two refugee camps and one protected area were analyzed using ANOVA and canonical correspondence analysis（CCA）. The normalized differential vegetation index（NDVI） and canopy cover around all village types decreased with disturbance gradients, while the magnitude of change varied according to the type of settlement. Limited canopy cover was observed in refugee camps and new resettlements, compared to old resettlements and protected areas. Woody vegetation height class showed a J shaped distribution in all sites except refugee camps（RC）, indicating a decline in vegetation. CCA showed that variables like site type, altitude and disturbance gradient significantly affected the diversity of woody species at the different sites. Comparison of individual species responses to disturbances indicated that low fodder value invaders like Dichrostachys cinerea, and many Acacia species were increasing in proportion and coverage at the expense of some multipurpose species including Tamarindus indica, Diospyros mespiliformis, and Pterocarpus lucens. In the absence of regulated vegetation use, resettlements result in a decline in overall vegetation cover and a shift in floristic diversity in favor of invasive species.

关键词： resettlement woody vegetation CCA woodland rangelands NDVl Ethiopia

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