Tropical fruit trees constitute important biological resources in the global agrobiodiversity context. Unlike the tropical fruit trees of American and Asian origin, indigenous fruit trees (IFT) of tropical Africa have...Tropical fruit trees constitute important biological resources in the global agrobiodiversity context. Unlike the tropical fruit trees of American and Asian origin, indigenous fruit trees (IFT) of tropical Africa have scarcely achieved the status of international recognition in commodity markets and research arena outside Africa. This paper presented a critical review of the status of IFT in the Tropical African sub-regions (of West Africa, Central Africa, East Africa, Southern Africa and the Indian Ocean Islands) in relation to the introduced naturalised fruit trees from tropical America and Asia, threats to the diversity and sustainable use of IFT, analysis of the opportunities and challenges of developing IFT, as well as targets for crop improvement of the rich IFT of Tropical Africa. Domestication programme via relevant vegetative propagation techniques for priority IFT of the sub-regions was examined and advocated, in addition to the adoption of complementary conservation strategies, including Field GeneBanks in the management of the continent’s IFT diversity.展开更多
Mathematical models have been widely employed for the simulation of growth dynamics of annual crops,thereby performing yield prediction,but not for fruit tree species such as jujube tree(Zizyphus jujuba).The objective...Mathematical models have been widely employed for the simulation of growth dynamics of annual crops,thereby performing yield prediction,but not for fruit tree species such as jujube tree(Zizyphus jujuba).The objectives of this study were to investigate the potential use of a modified WOFOST model for predicting jujube yield by introducing tree age as a key parameter.The model was established using data collected from dedicated field experiments performed in 2016-2018.Simulated growth dynamics of dry weights of leaves,stems,fruits,total biomass and leaf area index(LAI) agreed well with measured values,showing root mean square error(RMSE) values of 0.143,0.333,0.366,0.624 t ha^-1 and 0.19,and R2 values of 0.947,0.976,0.985,0.986 and 0.95,respectively.Simulated phenological development stages for emergence,anthesis and maturity were 2,3 and 3 days earlier than the observed values,respectively.In addition,in order to predict the yields of trees with different ages,the weight of new organs(initial buds and roots) in each growing season was introduced as the initial total dry weight(TDWI),which was calculated as averaged,fitted and optimized values of trees with the same age.The results showed the evolution of the simulated LAI and yields profiled in response to the changes in TDWI.The modelling performance was significantly improved when it considered TDWI integrated with tree age,showing good global(R2≥0.856,RMSE≤0.68 t ha^-1) and local accuracies(mean R2≥0.43,RMSE≤0.70 t ha^-1).Furthermore,the optimized TDWI exhibited the highest precision,with globally validated R2 of 0.891 and RMSE of 0.591 t ha^-1,and local mean R2 of 0.57 and RMSE of 0.66 t ha^-1,respectively.The proposed model was not only verified with the confidence to accurately predict yields of jujube,but it can also provide a fundamental strategy for simulating the growth of other fruit trees.展开更多
Environmental management intervention benefits have been found to depend on beneficiaries’ unique socioeconomic-environmental factors and understanding these helps generate knowledge guidelines for designing, plannin...Environmental management intervention benefits have been found to depend on beneficiaries’ unique socioeconomic-environmental factors and understanding these helps generate knowledge guidelines for designing, planning and implementation of new interventions. The Ecosystems Alliance (EA) Project in Uganda’s Albertine Rift promoted interventions including, resource access from protected areas, monitoring oil companies’ compliance to set environmental standards, tree planting, lake bank restoration, bee keeping, hay for livestock feeding and cages to shelter communities from crocodiles for four years in Buliisa, Hoima and Kasese district, to, build management capacity of the local communities and institutions to remedy the region’s environment and natural resources which were declining. At the end of the project we interviewed 56 representatives of the project beneficiaries individually and obtained data on benefit level, factors underpinning and perceived livelihoods and environmental impacts of the interventions and used Statistical Package for Social Scientists (SPSS) version 16 (Bryman & Cramer, 2009) to generate percentages (%), correlations with p ≤ 0.05 considered as significant relationship on these. As results, ≥90% of respondents in districts benefited from EA project interventions. Beneficiaries perceived the interventions that enhanced their household incomes and this was especially important for those who were not educated (<em>p</em> = 0.01, for education level);the environment management capacity and this was especially important for women (<em>p</em> = 0.05, for sex) and for households of 4 - 6 members (<em>p</em> = 0.02 with family size);the reduced conflicts with wildlife and this was especially important for households with 4 - 6 members (<em>p</em> = 0.02) and for people who depended on wetlands/wildlife resources (<em>p</em> = 0.00 for both cases) among others. Among constraints to benefit, time of intervention and climatic conditions was especially important among crop farmers (<em>p</em> = 0.04 with occupation) while, intervention not meeting expectation was a factor among beneficiaries in the age group 18 - 31 and 61 - 70 years old (<em>p</em> = 0.01, for age). The respondents recommended future initiatives start with research to determine interventions that match their environment, priority and expectations and these are distributed equitably after prior information/expectation management and technical capacity building.展开更多
文摘Tropical fruit trees constitute important biological resources in the global agrobiodiversity context. Unlike the tropical fruit trees of American and Asian origin, indigenous fruit trees (IFT) of tropical Africa have scarcely achieved the status of international recognition in commodity markets and research arena outside Africa. This paper presented a critical review of the status of IFT in the Tropical African sub-regions (of West Africa, Central Africa, East Africa, Southern Africa and the Indian Ocean Islands) in relation to the introduced naturalised fruit trees from tropical America and Asia, threats to the diversity and sustainable use of IFT, analysis of the opportunities and challenges of developing IFT, as well as targets for crop improvement of the rich IFT of Tropical Africa. Domestication programme via relevant vegetative propagation techniques for priority IFT of the sub-regions was examined and advocated, in addition to the adoption of complementary conservation strategies, including Field GeneBanks in the management of the continent’s IFT diversity.
基金supported by the National Natural Science Foundation of China(41561088 and 61501314)the Science&Technology Nova Program of Xinjiang Production and Construction Corps,China(2018CB020)
文摘Mathematical models have been widely employed for the simulation of growth dynamics of annual crops,thereby performing yield prediction,but not for fruit tree species such as jujube tree(Zizyphus jujuba).The objectives of this study were to investigate the potential use of a modified WOFOST model for predicting jujube yield by introducing tree age as a key parameter.The model was established using data collected from dedicated field experiments performed in 2016-2018.Simulated growth dynamics of dry weights of leaves,stems,fruits,total biomass and leaf area index(LAI) agreed well with measured values,showing root mean square error(RMSE) values of 0.143,0.333,0.366,0.624 t ha^-1 and 0.19,and R2 values of 0.947,0.976,0.985,0.986 and 0.95,respectively.Simulated phenological development stages for emergence,anthesis and maturity were 2,3 and 3 days earlier than the observed values,respectively.In addition,in order to predict the yields of trees with different ages,the weight of new organs(initial buds and roots) in each growing season was introduced as the initial total dry weight(TDWI),which was calculated as averaged,fitted and optimized values of trees with the same age.The results showed the evolution of the simulated LAI and yields profiled in response to the changes in TDWI.The modelling performance was significantly improved when it considered TDWI integrated with tree age,showing good global(R2≥0.856,RMSE≤0.68 t ha^-1) and local accuracies(mean R2≥0.43,RMSE≤0.70 t ha^-1).Furthermore,the optimized TDWI exhibited the highest precision,with globally validated R2 of 0.891 and RMSE of 0.591 t ha^-1,and local mean R2 of 0.57 and RMSE of 0.66 t ha^-1,respectively.The proposed model was not only verified with the confidence to accurately predict yields of jujube,but it can also provide a fundamental strategy for simulating the growth of other fruit trees.
文摘Environmental management intervention benefits have been found to depend on beneficiaries’ unique socioeconomic-environmental factors and understanding these helps generate knowledge guidelines for designing, planning and implementation of new interventions. The Ecosystems Alliance (EA) Project in Uganda’s Albertine Rift promoted interventions including, resource access from protected areas, monitoring oil companies’ compliance to set environmental standards, tree planting, lake bank restoration, bee keeping, hay for livestock feeding and cages to shelter communities from crocodiles for four years in Buliisa, Hoima and Kasese district, to, build management capacity of the local communities and institutions to remedy the region’s environment and natural resources which were declining. At the end of the project we interviewed 56 representatives of the project beneficiaries individually and obtained data on benefit level, factors underpinning and perceived livelihoods and environmental impacts of the interventions and used Statistical Package for Social Scientists (SPSS) version 16 (Bryman & Cramer, 2009) to generate percentages (%), correlations with p ≤ 0.05 considered as significant relationship on these. As results, ≥90% of respondents in districts benefited from EA project interventions. Beneficiaries perceived the interventions that enhanced their household incomes and this was especially important for those who were not educated (<em>p</em> = 0.01, for education level);the environment management capacity and this was especially important for women (<em>p</em> = 0.05, for sex) and for households of 4 - 6 members (<em>p</em> = 0.02 with family size);the reduced conflicts with wildlife and this was especially important for households with 4 - 6 members (<em>p</em> = 0.02) and for people who depended on wetlands/wildlife resources (<em>p</em> = 0.00 for both cases) among others. Among constraints to benefit, time of intervention and climatic conditions was especially important among crop farmers (<em>p</em> = 0.04 with occupation) while, intervention not meeting expectation was a factor among beneficiaries in the age group 18 - 31 and 61 - 70 years old (<em>p</em> = 0.01, for age). The respondents recommended future initiatives start with research to determine interventions that match their environment, priority and expectations and these are distributed equitably after prior information/expectation management and technical capacity building.
