EVALUATING THE RELATIVE CONTRIBUTION OF CHANGING FARMING METHODS TO HABITAT LOSS IN THE MID-ZAMBEZI VALLEY, ZIMBABWE

Agriculture expansion is a major contributor to wildlife habitat loss in the ecological frontier areas. However, little is known about the contribution of different crops to wildlife habitat loss. In this study we evaluated the relative contribution of changes in farming practices, particularly the introduction of cotton (Gossypium hirsutum L) to the loss of wildlife habitat with specific focus on the African elephant (Loxodonta africana) in the mid- Zambezi Valley, Zimbabwe. First, we developed a remote sensing method based on normalised difference vegetation index (NDVI) derived from 16 day multi-temporal Moderate Resolution Imaging Spectroradiometer (MODIS) remotely sensed data for the 2007 growing period, to test whether cotton (Gossypium hirsutum L) fields can significantly (p < 0.05) be distinguished from maize (Zea mays L) fields, as well as sorghum (Sorghum bicolor) fields. Second, we tested whether woodland fragmentation in the study area was best explained by the areal extent of cotton fields than the areal extent of cereal fields. Finally, we tested whether woodland fragmentation resulting from cotton fields explains elephant distribution better than woodland fragmentation resulting from the extent of cereal fields. Results show that multi-temporal remotely sensed data can be used to distinguish and map cotton and cereal fields. Cotton fields contributed more to woodland fragmentation than cereal fields. Also, we found out that woodland fragmentation from cotton fields significantly explained elephant distribution in the mid- Zambezi Valley. These results indicate that the areal extent of cotton fields explains elephant habitat fragmentation more than the areal extent of cereal fields. Thus, we conclude that the expansion of cotton fields contributes most to elephant habitat loss in the Mid-Zambezi Valley. These results imply that elephant conservation policy needs to address the reduction of the negative impact of cash crops such as cotton on the habitat particularly their threat to wildlife habitat which may eventually lead to loss these wild animals. Thus it is important to strike a balance between wildlife habitat conservation and agricultural production as advocated through the Communal Areas Management Programme For Indigenous Resources (CAMPFIRE) polic

Parareal in time 3D numerical solver for the LWR Benchmark neutron diffusion transient model

We present a parareal in time algorithm for the simulation of neutron diffusion transient model. The method is made efficient by means of a coarse solver defined with large time steps and steady control rods model. Using finite element for the space discretization, our implementation provides a good scalability of the algorithm. Numerical results show the efficiency of the parareal method on large light water reactor transient model corresponding to the Langenbuch-Maurer-Werner (LMW) benchmark [1]

Crop varieties research and implications on closing yield gaps and diversifying incomes—Africa RISING experiences

United States Agency for International Developmen

Quality of life: psychological symptoms-effects of a 2-month healthy diet and nutraceutical intervention; a randomized, open-label intervention trial (RISTOMED)

Depression symptoms and lower health-related quality of life (HRQoL) are associated with inflammation. This multicenter dietary intervention was shown to reduce inflammation in older people. This was the main outcome. Here, we describe the effects on HRQoL, anxiety, and depressive symptoms according to inflammation status. Overall, 125 healthy older subjects (65-80 year) were recruited (Italy, France, and Germany) and randomized into four arms (A, Healthy diet (HD); B, HD plus De Simone Formulation probiotic blend; C, HD plus AISA d-Limonene; D, HD plus Argan oil). The HD was weight maintaining, rich in antioxidant vitamins, polyphenols, polyunsaturated fatty acids (n6: n3 ratio = 3:1), and fiber. Data on inflammatory parameters, mental (MCS) and physical (PCS) component summaries of HRQoL (SF-36), anxiety symptoms (STAI state), and depressive symptoms (CES-D) were collected before and after 56 days of intervention. Body fat mass proportion (BFM) was considered a co-variable. A decrease of CES-D score was seen in the four arms (A: -40.0%, p = 0.001; B: -32.5%, p = 0.023; C: -42.8%, p = 0.004; and D: -33.3%, p = 0.21). Within the subgroups of subjects with medium/high inflammation a similar decrease in CES-D score occurred in all groups (A: -44.8%, p = 0.021; B, -46.7%, p = 0.024; C, -52.2%, p = 0.039; D, -43.8%, p = 0.037). The effect of interventions on CES-D was not related to baseline inflammation. MCS-HRQoL improved in A and C. There was no change in anxiety or PCS-HRQoL. In this trial with no control group, a decrease in depressive symptoms in healthy older volunteers was observed after a 2-month healthy diet intervention, independently of inflammation but with possible limitations due to participation

Genetic intensification: Africa RISING science, innovations and technologies with scaling potential from the Ethiopian Highlands

United States Agency for International Developmen

The input reduction principle of agroecology is wrong when it comes to mineral fertilizer use in sub-Saharan Africa

Can farmers in sub-Saharan Africa (SSA) boost crop yields and improve food availability without using more mineral fertilizer? This question has been at the center of lively debates among the civil society, policy-makers, and in academic editorials. Proponents of the “yes” answer have put forward the “input reduction” principle of agroecology, i.e. by relying on agrobiodiversity, recycling and better efficiency, agroecological practices such as the use of legumes and manure can increase crop productivity without the need for more mineral fertilizer. We reviewed decades of scientific literature on nutrient balances in SSA, biological nitrogen fixation of tropical legumes, manure production and use in smallholder farming systems, and the environmental impact of mineral fertilizer. Our analyses show that more mineral fertilizer is needed in SSA for five reasons: (i) the starting point in SSA is that agricultural production is “agroecological” by default, that is, very low mineral fertilizer use, widespread mixed crop-livestock systems and large crop diversity including legumes, but leading to poor soil fertility as a result of widespread soil nutrient mining, (ii) the nitrogen needs of crops cannot be adequately met solely through biological nitrogen fixation by legumes and recycling of animal manure, (iii) other nutrients like phosphorus and potassium need to be replaced continuously, (iv) mineral fertilizers, if used appropriately, cause little harm to the environment, and (v) reducing the use of mineral fertilizers would hamper productivity gains and contribute indirectly to agricultural expansion and to deforestation. Yet, the agroecological principles directly related to soil fertility—recycling, efficiency, diversity—remain key in improving soil health and nutrient-use efficiency, and are critical to sustaining crop productivity in the long run. We argue for a nuanced position that acknowledges the critical need for more mineral fertilizers in SSA, in combination with the use of agroecological practices and adequate policy support

People, Patches, and Parasites: The Case of Trypanosomiasis in Zimbabwe

Understanding the socio-ecology of disease requires careful attention to the role of patches within disease landscapes. Such patches, and the interfaces between different socio-epidemiological systems, we argue, have important implications for disease control.We conducted an interdisciplinary study over three years to investigate the spatial dynamics of human and animal trypanosomiasis in the Zambezi valley, Zimbabwe. We used a habitat niche model to identify changes in suitable habitat for tsetse fly vectors over time, and this is related to local villagers’ understandings of where flies are found. Fly trapping and blood DNA analysis of livestock highlighted the patchy distribution of both flies and trypanosome parasites. Through livelihoods analysis we explored who makes use of what areas of the landscape and when, identifying the social groups most at risk. We conclude with a discussion of the practical implications, including the need for an integrated ‘One Health’ approach involving targeted approaches to both vector control and surveillance

On the Adaptive Security of MACs and PRFs

We consider the security of two of the most commonly used cryptographic primitives—message authentication codes (MACs) and pseudorandom functions (PRFs)—in a multi-user setting with adaptive corruption. Whereas is it well known that any secure MAC or PRF is also multi-user secure under adaptive corruption, the trivial reduction induces a security loss that is linear in the number of users. Our main result shows that black-box reductions from “standard” assumptions cannot be used to provide a tight, or even a linear-preserving, security reduction for adaptive multi-user secure deterministic stateless MACs and thus also PRFs. In other words, a security loss that grows with the number of users is necessary for any such black-box reduction

Marine fish traits follow fast-slow continuum across oceans

A fundamental challenge in ecology is to understand why species are found where they are and predict where they are likely to occur in the future. Trait-based approaches may provide such understanding, because it is the traits and adaptations of species that determine which environments they can inhabit. It is therefore important to identify key traits that determine species distributions and investigate how these traits relate to the environment. Based on scientific bottom-trawl surveys of marine fish abundances and traits of >1,200 species, we investigate trait-environment relationships and project the trait composition of marine fish communities across the continental shelf seas of the Northern hemisphere. We show that traits related to growth, maturation and lifespan respond most strongly to the environment. This is reflected by a pronounced “fast-slow continuum” of fish life-histories, revealing that traits vary with temperature at large spatial scales, but also with depth and seasonality at more local scales. Our findings provide insight into the structure of marine fish communities and suggest that global warming will favour an expansion of fast-living species. Knowledge of the global and local drivers of trait distributions can thus be used to predict future responses of fish communities to environmental change.Postprint2,92