Eastern Zambia Research Articles

Holocene paleoenvironmental change in southeastern Africa (Makwe Rockshelter, Zambia): Implications for the spread of pastoralism

Abstract The paleoenvironmental conditions surrounding the origins of pastoralism and the movement of herders from eastern to southern Africa sometime between ∼4000 and 2000 ybp have been much debated. We lack, however, detailed paleoenvironmental data from sites sampling the hunter-to-herder transition in southeastern Africa, the likely corridor from eastern to southern Africa for early pastoralists. Here we report on new paleoenvironmental data from a site in the under-sampled area of eastern Zambia, Makwe Rockshelter, which has two aggregates of archaeological horizons representing the mid-Holocene (∼5700-5000 ybp) and the late Holocene (∼1600-800 ybp). The mid-Holocene sediments at Makwe document a foraging society, whereas the late Holocene sediments include both wild game and domestic livestock. Using stable carbon isotopes (δ13C) of herbivore enamel (n = 107), we show that the shift from mid-Holocene to late Holocene paleoenvironments was characterized by an increase in C4 vegetation. These data are complemented by paleoenvironmental records from Lake Malawi that show that C4 vegetation peaked after ∼2000 ybp and was coincident with the onset of cooler, more arid climates. This combined paleoenvironmental record has implications for the spread of pastoralism across southeastern Africa between ∼3000 and 2000 ybp and potential ‘animal disease barriers’ these early herders may have faced.

English

Small-scale farmers in Zambia are faced with problems of low crop productivity, scarcity of fuel wood and fodder, and subsequently are generally food insecure. Agroforestry can contribute to food and income security, amelioration of the environment and subsequently, to mitigation of climate change effects. However, despite all the potential of agroforestry technologies and the effort to promote them among smallholder farmers, their adoption and diffusion have remained low and so has their impact. Unless farmers adopt some of these technologies as part of their farming system, the potential benefits of agroforestry to food security, livelihoods and the environment will not be realized. This study investigated trialing and adoption levels of agroforestry in eastern Zambia where agroforestry has been researched and promoted for over two decades. A survey was completed of 388 small scale farmers. Data analysis shows that testing of improved fallows and biomass transfer, though low at 44.9 and 21.4% respectively, was higher than that of domestication of indigenous fruits (4.4%), Fodder banks (3.9%) and Woodlots (3.1%). The study however found that adoption rate of agroforestry among farmers that initially tested is high. Factors that affect adoption include lack of seed, limited land size, method of ploughing, lack of interest and access to extension services. Therefore we advocate for intensified promotion and encouragement support so that more farmers can trial these technologies. With high trialing rates, adoption of agroforestry is likely to increase. The key policy implication of this study is the necessity to embark on educating farmers so that they can trial and subsequently experience the impact of agroforestry technologies. Agroforestry will only make meaningful contribution to improving land productivity and farmer livelihoods if it is adopted. Key words: Adoption, agroforestry, biomass transfer, improved tree fallows, logistic regression, smallholder farmers, Zambia.

Evaluation of outpatient therapeutic programme for management of severe acute malnutrition in three districts of the eastern province, Zambia

Severe acute malnutrition (SAM) in children under 5 years of age is a major cause of child mortality during hospital admission worldwide, and is attributed to poor case management. The Outpatient Therapeutic Programme (OTP) is an innovation for treating children with SAM with no medical complications as outpatients within their communities. The aim of the study was to evaluate the improvement in health outcomes and case fatality rate in children aged 6–59 months diagnosed with SAM and admitted in OTP centres, and to document the barriers to a sustainable OTP intervention in the districts of Eastern Zambia. A mixed-methods design was used to assess the health outcomes of OTP intervention. Three districts where OTP centres were operational at the time of study were selected. Records of 390 eligible children admitted with SAM between 2008 and 2010 were reviewed. The health outcomes assessed included recovery and case fatality rates, defaulter rate, and weight gain. Information on the barriers to effective implementation of a sustainable OTP intervention in the districts was collected through semi-structured key-informant interviews with stakeholders. Outcome indicators were compared with the baseline data and recommended minimum standards for therapeutic feeding centres. Of the 390 children admitted into OTP, 312 (80 %) had recovered on discharge, 11 (2.8 %) died, and 67 (17.2 %) had defaulted. Compared to the baseline data and the recommended minimum standard values, case fatality rate for this study was 2.8 % vs. 7.3 % vs. >10 % respectively, and the recovery rate was 80 % vs. 73 % vs. >75 % respectively. Barriers to effective sustainability of the programme included dependence on donor-funds, consistent stock outs of ready-to-use therapeutic food and other supplies, high volunteer dropout, and inadequate monitoring and feedback on defaulters. OTP improved health outcomes of SAM children in the Eastern Zambia when compared with accepted minimum standards and previous data. Dependent on donor funding and the resultant regular stock-out of supplies can, however, hamper sustainability in the long-term.

Molecular, serological and epidemiological observations after a suspected outbreak of plague in Nyimba, eastern Zambia.

Plague is a re-emerging zoonotic disease caused by the bacterium Yersinia pestis. The disease has caused periodic global devastation since the first outbreak in the 6th century. Two months after a suspected plague outbreak in Nyimba district, samples were collected from 94 livestock (goats and pigs), 25 rodents, 6 shrews and 33 fleas. Enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) techniques were used to investigate the presence of Y. pestis, which showed that 16.0% (4/25) of rodents, 16.7% (1/6) of shrews (Crocidura spp) and 6.0% (5/83) of goats were positive for IgG antibodies against Fraction 1 antigen of Y. pestis. Plasminogen activator (Pla) gene (DNA) of Y. pestis was detected in five pools containing 36.4% (12/33) fleas collected from pigs (n = 4), goats (n = 5) and rodents (n = 3). The detection of Pla gene in fleas and IgG antibodies against Fraction1 antigen in rodents, shrews and goats suggest that Y. pestis had been present in the study area in the recent past.

How Can Multifunctional Agriculture Support a Transition to a Green Economy in Africa? Lessons from the COMACO Model in Zambia

This paper examines the link between the green economy and multifunctional agriculture. In particular, the paper uses the case of the Community Markets for Conservation (COMACO) initiative, an agro-based enterprise promoting a multifunctional agriculture model in Eastern Zambia, to examine how the potential of smallholder farmers can be harnessed to support a transition towards the green economy. The empirical data on which the paper is based were collected through questionnaire surveys and in-depth interviews conducted with farmers and other actors in the agricultural sector. The results of the study show that a number of elements underpinning the COMACO model including sustainable land management practices, conservation outreach, community markets, value addition, and conservation dividends have great potential to deliver benefits related to the green economy. However, to truly foster a transition towards a green economy, a number of constraints need to be overcome. These include lack of a supportive policy and institutional framework, technological backwardness, and lack of consumer awareness of environmental information instruments such as eco-labelling.

A retrospective study and predictive modelling of Newcastle Disease trends among rural poultry of eastern Zambia

Newcastle Disease (ND) is a highly infectious disease of poultry that seriously impacts on food security and livelihoods of livestock farmers and communities in tropical regions of the world. ND is a constant problem in the eastern province of Zambia which has more than 740 000 rural poultry. Very few studies give a situational analysis of the disease that can be used for disease control planning in the region. With this background in mind, a retrospective epidemiological study was conducted using Newcastle Disease data submitted to the eastern province headquarters for the period from 1989 to 2014. The study found that Newcastle Disease cases in eastern Zambia followed a seasonal and cyclic pattern with peaks in the hot dry season (Overall Seasonal Index 1.1) as well as cycles every three years with an estimated provincial incidence range of 0.16 to 1.7% per year. Annual trends were compared with major intervention policies implemented by the Zambian government, which often received donor support from the international community during the study period. Aid delivered through government programmes appeared to have no major impact on ND trends between 1989 and 2014 and reasons for this are discussed. There were apparent spatial shifts in districts with outbreaks over time which could be as a result of veterinary interventions chasing outbreaks rather than implementing uniform control. Data was also fitted to a predictive time series model for ND which could be used to plan for future ND control. Time series modelling showed an increasing trend in ND annual incidence over 25 years if existing interventions continue. A different approach to controlling the disease is needed if this trend is to be halted. Conversely, the positive trend may be a function of improved reporting by farmers as a result of more awareness of the disease.

‘People are Trying to be Modern’: Food Insecurity and the Strategies of the Poor

The failure of rural Africans to heed the message of development projects and improve agricultural practices is widely recognized as a problem in terms of food security and rural development. This study focuses on the situation in one locality of eastern Zambia and adopts a qualitative approach. By looking at local cultural issues a different understanding of the mechanisms of this failure may be attempted. We suggest that food provisioning is constructed in reference to an ideal of modernity in which subsistence production takes a particular (and gendered) relationship to the cash economy. The implication is that subsistence agriculture is conceived as ‘reproduction’ within capitalism rather than as a separate mode of production articulated with capitalism. This ideal of modernity and the associated utopia of food provisioning make it difficult for rural households in Zambia to see sustainable subsistence agriculture as any kind of a way forward.

Use of a Nutrition Behavior Change Counseling Tool: Lessons from a Rapid Qualitative Assessment in Eastern Zambia.

The U.S. Agency for International Development Feed the Future Mawa Project – led by Catholic Relief Services – aims to improve food and economic security for farming households in Zambia’s Eastern Province. Mawa employs social and behavior change (SBC) strategies with households and communities to improve nutrition and reduce stunting among children under two (CU2). To support these strategies, sub-partner University Research Co., LLC employed a participatory process to develop a series of 35 action cards, each illustrating one project-promoted behavior, that are used at household and community group levels. Caregivers of CU2 are given a full set of action cards to promote household dialogue and support for the promoted behaviors. As a final step in the action card tool development process, a qualitative rapid assessment was conducted 1 month after implementation to investigate preliminary ways action cards were being used, and if the methods of using the cards had the potential to impact behavior change. The research team conducted nine key informant interviews and four focus group discussions with Mawa staff and administered 41 qualitative interview questionnaires with project participants in the Chipata and Lundazi districts. Although not based on a representative sampling frame, the assessment produced valuable results for program improvement purposes. It also provided a feedback mechanism for community-based staff and project participants, a crucial step in the participatory tool development process. The assessment found that Mawa staff at every level use action cards combined with at least one other social behavior change tool for each nutrition intervention. Our results suggest that Mawa staff and project participants share a common understanding of the cards’ purpose. Each group noted that the cards provide a visual cue for action and reinforce previous Mawa nutrition messages. Intended uses confirmed by the assessment include encouraging household cooperation, negotiating behavior change, telling stories, and integrating messages with other project sectors. Based on the findings, recommendations for future project activities include aligning efforts against a theory of change to optimize use of all SBC tools; leveraging action card use to strengthen cross-sectoral integration within Mawa; and specific ongoing monitoring of action card use to improve activity implementation.

Identification and Toxigenicity ofAspergillusspp. from Soils Planted to Peanuts in Eastern Zambia

ABSTRACTIt is not known which aflatoxigenic species are present in Zambia. Therefore, soil samples were collected during May to June 2012, at the end of the growing season in Eastern Province, from 399 farmers' fields that had been planted to groundnut (Arachis hypogaea L.) in Nyimba, Petauke, Mambwe, and Chipata Districts. Population densities of Aspergillus spp. were estimated by plating 10−3 soil dilutions on modified dichloran rose Bengal (MDRB) media. To test for toxigenicity, colonies were randomly selected from MDRB dilution plates, single-spored, transferred to vials with yeast extract sucrose (YES) liquid media, and grown for a week at room temperature. Agra Strip ® lateral flow cards were then used to test the filtered extracts, from the YES cultures, for total aflatoxin at 4 and 20 parts per billion (ppb). We identified Aspergillus flavus (small and large sclerotia strains), A. parasiticus, A. niger, A. nomius, A. oryzae, A. tamarii, and A. terreus. 100% of the S-strain A. flavus isolates produced aflatoxin at 4 and 20 ppb, whereas 86% and 56% of the L-strain A. flavus isolates produced aflatoxins at 4 and 20 ppb, respectively. All the A. nomius isolates produced aflatoxins at 4 and 20 ppb. 79% and 64% the A. parasiticus isolates produced aflatoxins at 4 and 20 ppb. To our knowledge, this is the first peer reviewed report from Zambia documenting the population densities of A. flavus across different agroecologies. In addition, it is also the first report on the identification of different Aspergillus spp., such as A. nomius, A. terreus, A. oryzae, and A. tamarii from Zambia. This information, taken together with cropping practices, soil characteristics, agroecological and climatic data, can form a basis for developing holistic pre-harvest aflatoxin mitigation strategies.

Determinants of adoption and disadoption of minimum tillage by cotton farmers in eastern Zambia

Conservation agriculture (CA) is heralded as a means to increase yields and reverse land degradation in sub-Saharan Africa, but low adoption levels have led to concerns about its suitability for smallholder farming systems. Combining data from surveys and semi-structured interviews, we examine farmers’ motivations for adopting CA and the determinants of adoption and disadoption of hand-hoe and oxen-drawn minimum tillage (MT), a key component of CA. Farmers generally hold favorable opinions about MT, though not for its benefits to the soil but primarily for how it reduces crop losses from erratic rainfall. MT use rates in communities with the highest adoption rates are relatively low (12% of cotton area and 20% of maize area) and disadoption is common (25% of all farmers). Many farmers are interested in adopting MT but the available MT technologies do not match their resource endowments. Labor constraints limit use of hand-hoe basins while equipment costs limit ox-ripping. These results show that farmers are not stuck in traditional hoeing and plowing but are carefully evaluating the benefits and costs of adopting MT. Widespread adoption of CA will require adapting MT technologies to match a broader range of resource endowments.

Why pigs are free-roaming: Communities’ perceptions, knowledge and practices regarding pig management and taeniosis/cysticercosis in a Taenia solium endemic rural area in Eastern Zambia

Taenia solium cysticercosis is a neglected parasitic zoonosis in many developing countries including Zambia. Studies in Africa have shown that the underuse of sanitary facilities and the widespread occurrence of free-roaming pigs are the major risk factors for porcine cysticercosis. Socio-cultural determinants related to free range pig management and their implications for control of T. solium remain unclear.The study objective was to assess the communities’ perceptions, reported practices and knowledge regarding management of pigs and taeniosis/cysticercosis (including neurocysticercosis) in an endemic rural area in Eastern Zambia, and to identify possible barriers to pig related control measures such as pig confinement. A total of 21 focus group discussions on pig husbandry practices were organized separately with men, women and children, in seven villages from Petauke district.The findings reveal that the perception of pigs and their role in society (financial, agricultural and traditional), the distribution of the management tasks among the family members owning pigs (feeding, building kraal, seeking care) and environmental aspects (feed supply, presence of bush, wood use priorities, rainy season) prevailing in the study area affect pig confinement. People have a fragmented knowledge of the pork tapeworm and its transmission. Even if negative aspects/health risks of free-range pigs keeping are perceived, people are ready to take the risk for socio-economic reasons. Finally, gender plays an important role because women, and also children, seem to have a higher perception of the risks but lack power in terms of economic decision-making compared to men.Currently pig confinement is not seen as an acceptable method to control porcine cysticercosis by many farmers in Eastern Zambia, vaccination and treatment seemed to be more appropriate. Embedded in a One Health approach, disease control programs should therefore ensure a complementary appropriate set of control strategies by engaging new sectors such as agronomy, spatial ecology and finally consider the socio-cultural context, which is likely to enhance the development of control methods that could be accepted by the communities.

'A child is also a teacher': exploring the potential for children as change agents in the context of a school-based WASH intervention in rural Eastern Zambia.

As part of water, sanitation and hygiene interventions in low-income settings, it is frequently assumed that pupils can disseminate information and catalyze change at home, yet this assumption has not been rigorously assessed. We employed qualitative research methods in two phases to assess the potential for children to be change agents in five schools in rural Zambia. Phase 1 included role-play and focus group discussions among pupils on their percieved ability to serve as change agents. Children were then given 'homework' that included information on health messages and on how to build a handwashing station, and were encouraged to engage their family. In Phase 2, we conducted separate focus group discussions with pupils and mothers on their experiences with the 'homework'. We found that, in general, pupils were enthusiastic about engaging with parents-typically male heads of household-and were successful at constructing handwashing stations. Mothers reported high levels of trust in children to relay health information learned at school. Pupils were able to enact small changes to behavior, but not larger infrastructure changes, such as construction of latrines. Pupils are capable of communicating knowledge and behaviors to family members; however, discrete activities and guidance is required.

Motor skills and verbal fluency in HIV positive older adults in Rural Eastern Zambia

Objectives: To investigate the performance of HIV infected older adults resident in a rural area in Eastern Zambia with low education level on the motor skills and verbal fluency.Materials and Methods: A quantitative and cross sectional study consisting of 28 HIV positive and 22 HIV negative rural resident adults in Chipata with the age range of 40-65years with fewer than five years of education. The present sub study extended the generalisability of the Zambia Neurobehavioral Test Battery (ZNTB) findings with literate, urban adults in the main study to a sample of less formally educated, elderly, rural adults, using tests of motor skill and some verbal fluency tests translated into local language, that were not expected to depend on formal education. The main sample study included 41 participants with the education range of 5-7 years drawn from the main sample in the 6 clinics in Lusaka. Some aspects of the ZNTB were used to measure cognitive functioning. The Finger Tapping Test of the Developmental Neuropsychological Test Battery was also used.Results: Tests of motor skill were less sensitive to HIV infection (F (1, 48) = 1.134, p= .292) than verbal fluency tests-Hopkins Verbal Learning (F (1, 48) = 42.994, p=.000, Hopkins Verbal Learning Test- delay (F (1, 48) = 45.886, p= .000, Animal Naming (F(1, 48) = 14.772, p= .000 and Action Naming (F (1, 48) = 14.227, p= .000). Contrary to hypothesis, performance on the grooved pegboard test of motor skill was significantly higher by participants with full primary education (Z score= -0.90) than by less educated participants (Z score= 1.80).Conclusions: This study has brought to light what was not known about the effect of HIV and education on the performance of the motor tasks and verbal fluency among the low literate adults. It has shown that regardless of the HIV status individuals can perform tasks normally on the motor tasks more especially with the improved treatment of HIV.

How by-laws and collective action influence farmers’ adoption of agroforestry and natural resource management technologies: lessons from Zambia

Customary practices such as bush fires and the browsing by livestock, and the absence of land property rights are important institutional constraints to effective up-scaling of natural resource management (NRM) including agroforestry technologies in southern Africa. Through collective action by communities in eastern Zambia, and supported by-laws enacted by traditional leaders to formalize them, the conflicts arising over resources in the communities and the quest to protect the interests of the different segments of the society were addressed. This paper investigates the process through which the by-laws were formulated and implemented, and evaluates their effectiveness to achieve the desired outcome. It then used a sample of 196 households to assess the impacts of the by-laws on household and social groups in the community. Results show that the by-laws have led to a remarkable reduction in the incidence of fire outbreak and grazing. It also highlights how traditional institutions can provide important entry points for local policy interventions on NRM in rural communities. The by-laws impacted positively on women-headed households and those who practice agroforestry, but children (boys) and livestock owners were disadvantaged. Lessons learnt from the study include: (i) the distribution of the benefits (or costs) associated with natural resource commons among different interest groups in the communities influence the effectiveness of by-laws on such resources; (ii) the dynamics of power structure existing in communities are critical determinants of the effectiveness of local policy interventions on NRM; (iii) privatizing seasonal commons is an important factor for designing policy interventions on NRM in rural communities. It is concluded that in addition to the technological characteristics of NRM interventions, local institutional arrangements and power structures existing in rural communities, and the pattern of distribution of benefits (or costs) of an NRM technology are important factors that influence their widespread adoption by farmers.

Mesoproterozoic UHT metamorphism in the Southern Irumide Belt, Chipata, Zambia: Petrology and in situ monazite dating

The Irumide Belt sensu lato of eastern Zambia situated between the Bangweulu Block and the Zimbabwe Craton is one of the Mesoproterozoic belts in southern Africa, which developed during the formation of the supercontinent Rodinia. Though in several of these belts the orogenic evolution seems to be connected to a long lasting high temperature history (∼200Ma), the duration and geodynamic causes of the metamorphism in this particular belt have not been studied.Here we report the results of an integrated petrological study and texturally controlled in situ monazite dating of spinel–quartz and orthopyroxene–cordierite granulites and associated charnockites and mafic rocks from the Chipata Terrane of the Southern Irumide Belt (SIB), which revealed a single stage high to ultra-high temperature (HT, UHT) metamorphism during the Mesoproterozoic Irumide orogeny. The earliest textural relicts of the prograde evolution are patchy sillimanite aggregates interpreted to represent pseudomorphs after andalusite. Sillimanite inclusions in garnet indicate garnet growth in the sillimanite stability field. During peak metamorphism garnet+sillimanite reacted to form spinel+quartz. In associated garnet–orthopyroxene–cordierite granulites, peak orthopyroxene has high Al2O3 contents of up to 7.9wt%. These peak metamorphic features point to UHT conditions of 900–1000°C (UHT) at ∼5–6kbar, in agreement with the occurrence of inverted pigeonite in associated charnockites. Orthopyroxene+cordierite coronas around prograde garnet in the second assemblage indicates decompression at UHT conditions after peak metamorphism. Subsequent isobaric cooling (IBC) led to reversal of mineral reactions and thus to replacement of spinel+quartz by garnet 2+sillimanite 2+cordierite. The IBC at still high pressures is also indicated by the formation of garnet and clinopyroxene coronas between orthopyroxene and plagioclase in associated mafic rocks. During late-stage retrogression the formation of kyanite+chlorite+quartz±staurolite±magnesite at the expense of cordierite and garnet in garnet–cordierite–sillimanite gneiss indicates prevailing high pressures (>4–5kbar) during cooling below temperatures of ∼550°C.Monazite grains occurring in different textural settings (inclusions in garnet, and in matrix) revealed ages between 1031±4 and 1013±4Ma for the peak HT to UHT metamorphism of the Chipata terrane of the SIB. The metamorphism is almost synchronous with the age of intracrustal melting in the northern Irumide Belt (IB; 1020–950Ma) and slightly younger than the age of continental margin arc magmatism in the SIB (∼1090–1040Ma). The metamorphism therefore most likely occurred as a consequence of subduction related magmatism and the collision between the IB (margin of the Bangweulu block) and the SIB (margin of an unknown southern craton) during the Mesoproterozoic Irumide orogeny.

A Multitemporal Profile-Based Interpolation Method for Gap Filling Nonstationary Data

Missing data in Landsat imagery caused by cloud cover and the scan line corrector error confound analysis, and effective methods for gap filling would greatly improve the usability of these data. Several methods for gap filling Landsat data have been proposed, but they typically assume little change in the images being corrected, which is a weakness in change detection applications. We present a profile-based $k$ -nearest-neighbor method for estimating missing spectral index data that provides accurate gap filling under both gradual and abrupt changes. The profile-based interpolator (PBI) uses a multitemporal image sequence and exploits similarities in land cover temporal profiles and spatial relationships to reliably estimate missing data. PBI uses both complete and incomplete pixel profiles to maximize information for estimation and aligns pixel profiles to the target pixel profile to minimize scale biases. For testing, we used eight-image mid-infrared bispectral index sequences from 2009 and 2014 for a study area in eastern Zambia. For ten stratified random samples $(n=\mathbf{1200})$ , we simulated one to six missing values per pixel profile and estimated the missing values at various $k$ values (5–29). Comparison of estimated with original values found results to be highly correlated ( $R^2$ of 0.95–0.72 for one to six missing values, respectively) and precise (mean absolute percent errors of 4%–8%). PBI provided comparable performance to a dictionary learning image recovery method with much better computational efficiency. PBI provides spatially and temporally consistent outputs, preserving abrupt changes in the imagery due to landscape fires even with large data gaps.

Capacity and Policy Change in Managing Human African Trypanosomiasis in Endemic Rural Districts of Eastern Zambia

Capacity and Policy Change in Managing Human African Trypanosomiasis in Endemic Rural Districts of Eastern Zambia

Determinants of child nutritional status in the eastern province of Zambia: the role of improved maize varieties

Using household survey data from a sample of 810 households, this paper analyses the determinants of children’s nutritional status and evaluates the impacts of improved maize varieties on child malnutrition in eastern Zambia. The paper uses an endogenous switching regression technique, combined with propensity score matching, to assess the determinants of child malnutrition and impacts of improved maize varieties on nutritional status. The study finds that child nutrition worsens with the age of the child and improves with education of household head and female household members, number of adult females in the household, and access to better sanitation. The study also finds a robust and significant impact of improved maize varieties on child malnutrition. The empirical results indicate that adoption of improved maize varieties reduces the probability of stunting by an average of about 26 %.

Unexpected diversity of Anopheles species in Eastern Zambia: implications for evaluating vector behavior and interventions using molecular tools.

The understanding of malaria vector species in association with their bionomic traits is vital for targeting malaria interventions and measuring effectiveness. Many entomological studies rely on morphological identification of mosquitoes, limiting recognition to visually distinct species/species groups. Anopheles species assignments based on ribosomal DNA ITS2 and mitochondrial DNA COI were compared to morphological identifications from Luangwa and Nyimba districts in Zambia. The comparison of morphological and molecular identifications determined that interpretations of species compositions, insecticide resistance assays, host preference studies, trap efficacy, and Plasmodium infections were incorrect when using morphological identification alone. Morphological identifications recognized eight Anopheles species while 18 distinct sequence groups or species were identified from molecular analyses. Of these 18, seven could not be identified through comparison to published sequences. Twelve of 18 molecularly identified species (including unidentifiable species and species not thought to be vectors) were found by PCR to carry Plasmodium sporozoites - compared to four of eight morphological species. Up to 15% of morphologically identified Anopheles funestus mosquitoes in insecticide resistance tests were found to be other species molecularly. The comprehension of primary and secondary malaria vectors and bionomic characteristics that impact malaria transmission and intervention effectiveness are fundamental in achieving malaria elimination.

English

Improved fallows of Sesbania sesban (Sesbania) have been known to improve soil physical and chemical properties and increase crop yield compared to traditional fallows. However, the effects of soil tillage practices after improved fallows on soil properties, weeds, labour and subsequent maize crop has not been assessed in Southern Africa. This study aimed to evaluate how tillage practices affect yield of maize and affect soil properties after two years of fallow and subsequent cropping phase. In this study, done at sites in eastern Zambia, maize yield from a two-year planted Sesbania, natural fallow, continuously fertilized and unfertilized maize were compared under conventional, flat till and zero tillage practices. A split plot experiment, with improved fallow systems in the main plot and the tillage practice in the subplot, was established at the sites. The results showed that the increases in grain yield under conventional tillage over zero tillage practice were 17.8 and 28.2% during 2000/2001 and 2001/2002 seasons, respectively, at Msekera. At Chadiza, the increases in grain yield under conventional tillage over zero tillage were 66.3 and 327.4% during 2000/2001 and 2001/2002 seasons, respectively. Greater maize yields were achieved under Sesbania planted fallows compared to the natural fallow and maize monoculture without fertilizer. Overall, zero tillage practice resulted in lower maize grain yield, higher bulk density, reduced water intake, higher weed infestation and high labour demand during weeding compared to conventional tillage. Key words: Conventional tillage, flat till, grain yield, water intake, weeds, zero tillage.