A study of the carbonized seeds from a La Tène D1 rural settlement, “Le Camp du Roi” excavation at Jaux (Oise), France

This paper presents the results of the study of the macroscopic plant remains found in the granary of a La Tène D1 native farm situated on the plateau overlooking the river Oise, near Compiègne, northern France. The composition and the deposition of the harvest in the storage building are discussed. Some evidence of agricultural practices are deduced from the weeds associated with the grain.     

Changes in mangrove vegetation area and character in a war and land use change affected region of Vietnam (Mui Ca Mau) over six decades

Aerial photographs and satellite images have been used to determine land cover changes during the period 1953 to 2011 in the Mui Ca Mau, Vietnam, especially in relation to changes in the mangrove area. The mangrove area declined drastically from approximately 71,345 ha in 1953 to 33,083 ha in 1992, then rose to 46,712 ha in 2011. Loss due to herbicide attacks during the Vietnam War, overexploitation, and conversion into agriculture and aquaculture encouraged by land management policies are being partially counteracted by natural regeneration and replanting, especially a gradual increase in plantations as part of integrated mangrove-shrimp farming systems. The nature of the mangrove vegetation has markedly been transformed over this period. The results are valuable for management planning to understand and improve the contribution of mangrove forests to the provision of ecosystem services and resources, local livelihood and global interest.     

Transparent Cuprous Oxide Photocathode Enabling a Stacked Tandem Cell for Unbiased Water Splitting

Photoelectrochemical water splitting represents an attractive method of capturing and storing the immense energy of sunlight in the form of hydrogen, a clean chemical fuel. Given the large energetic demand of water electrolysis, and the defined spectrum of photons available from incident sunlight, a two absorber tandem device is required to achieve high efficiencies. The two absorbers should be of different and complementary bandgaps, connected in series to achieve the necessary voltage, and arranged in an optical stack configuration to maximize the utilization of sunlight. This latter requirement demands a top device that is responsive to high‐energy photons but also transparent to lower‐energy photons, which pass through to illuminate the bottom absorber. Here, cuprous oxide (Cu₂O) is employed as a top absorber component, and the factors influencing the balance between transparency and efficiency toward operation in a tandem configuration are studied. Photocathodes based on Cu₂O electrodeposited onto conducting glass substrates treated with thin, discontinuous layers of gold achieve reasonable sub‐bandgap transmittance while retaining performances comparable to their opaque counterparts. This new high‐performance transparent photocathode is demonstrated in tandem with a hybrid perovskite photovoltaic cell, resulting in a full device capable of standalone sunlight‐driven water splitting.     

Cultivation of Microalgae in Dairy Farm Wastewater Without Sterilization

The present study investigated the feasibility of cultivating microalgae in dairy farm wastewater. The growth of microalgae and the removal rate of the nutrient from the wastewater were examined. The wastewater was diluted 20, 10 and 5 times before applied to cultivate microalgae. A 5 dilution yielded 0.86 g/L dry weight in 6 days with a relative growth rate of 0.28 d^?1, the 10× dilution gave 0.74 g/L and a relative growth rate of 0.26 d^?1 while the 20× dilution 0.59 g/L and a relative growth rate 0.23 d^?1. The nutrients in the wastewater could be removed effectively in different diluted dairy wastewater. The greatest dilution (20×) showed the removal rates: ammonia, 99.26%; P, 89.92%; COD, 84.18%. A 10× dilution removal% was: ammonia 93; P 91 and COD 88. The 5× dilution removal% was: ammonia 83; P 92; COD 90.     

Managing the transition from purebred to rotational crossbred dairy cattle herds: three technical pathways from a retrospective case-study analysis

The growing interest in rotational crossbreeding in Western countries is due to its potential to improve reproductive and health performances of cows. Although a large amount of research focuses on assessing crossbred cows’ performances, how to manage the transition from purebred to rotational crossbred herds is under-explored. Based on a retrospective analysis of French dairy herd case studies, we aimed to identify and characterise technical pathways to make such a transition. In 2018, we performed semi-directive interviews on 26 commercial dairy farms. Data were collected to describe changes in breeding, replacement and culling management practices from the first crossbred mating with purebred cows to the management of a mainly crossbred herd in 2018. Based on a multivariate analysis, we identified two main guidelines structuring technical pathways to move towards rotational crossbred herds: (i) the depth and scale of change (i.e. farm v. herd) associated with the introduction of rotational crossbreeding in the whole-farm dynamics and (ii) the changes in herd replacement and breeding practices to adapt to the evolution of herd demographics induced by the evolution of the dairy crossbred mating rate over time (high from the beginning v. distributed over time). Hierarchical clustering discriminated three groups of farmers differing in their technical pathway to move towards a rotational crossbred herd. In pathway 1, farmers customised one or several rotational crossbreeding schemes to support whole-farm transition towards an organic or grass-based system. Once the scheme stabilised, they quickly implemented it and had to readjust replacement and culling practices to regulate imbalance in herd demographics induced by the improvement in cow fertility. In pathway 2, farmers also customised one or several rotational crossbreeding schemes to support whole-farm redesign but they implemented it more gradually in the herd, which induced no major imbalance in herd demographics. In pathway 3, farmers predefined a relatively well-known rotational crossbreeding scheme to correct fertility issues of purebred cows without any changes at the farm level. They implemented it quickly from the beginning and had to adapt herd replacement and culling to regulate imbalance in herd demographics induced by the improvement in cow fertility. These first empirical evidences on how dairy farmers manage the transition from a purebred to rotational crossbred herd provide original scientific and operational contributions.     

Site‐specific life cycle assessment of a pilot floating offshore wind farm based on suppliers’ data and geo‐located wind data

Renewable energy systems are essential in coming years to ensure an efficient energy supply while maintaining environmental protection. Despite having low environmental impacts during operation, other phases of the life cycle need to be accounted for. This study presents a geo‐located life cycle assessment of an emerging technology, namely, floating offshore wind farms. It is developed and applied to a pilot project in the Mediterranean Sea. The materials inventory is based on real data from suppliers and coupled to a parameterized model which exploits a geographic information system wind database to estimate electricity production. This multi‐criteria assessment identified the extraction and transformation of materials as the main contributor to environmental impacts such as climate change (70% of the total 22.3 g CO₂ eq/kWh), water use (73% of 6.7 L/kWh), and air quality (76% of 25.2 mg PM2.5/kWh), mainly because of the floater's manufacture. The results corroborate the low environmental impact of this emerging technology compared to other energy sources. The electricity production estimates, based on geo‐located wind data, were found to be a critical component of the model that affects environmental performance. Sensitivity analyses highlighted the importance of the project's lifetime, which was the main parameter responsible for variations in the analyzed categories. Background uncertainties should be analyzed but may be reduced by focusing data collection on significant contributors. Geo‐located modeling proved to be an effective technique to account for geographical variability of renewable energy technologies and contribute to decision‐making processes leading to their development.     

Phosphorus feeding practices,barriers to and motivators for minimising phosphorus feeding to dairy cows in diverse dairy farming systems

Minimising phosphorus (P) feeding to dairy cows can reduce feed costs and minimise water pollution without impairing animal performance. This study aimed to determine current P feeding practices and identify the barriers to and motivators for minimising P feeding on dairy farms, using Great Britain (GB) dairy farming as an example of diverse systems. Farmers (n = 139) and feed advisers (n = 31) were involved simultaneously in independent questionnaire surveys on P feeding in dairy farms. Data on the herd size, milk yield and concentrate fed were analysed using ANOVA to investigate the effect of farm classification, region, and feed professional advice. Chi-square tests were used to investigate associations between farm characteristics and implemented P feeding and management practices. Most farmers (72%) did not know the P concentration in their lactating cow’s diet and did not commonly adopt precision P feeding practices, indicating that cows might have been offered dietary P in excess of recommended P requirement. Farmers’ tendency to feed P in excess of recommendations increased with herd size, but so did their awareness of P pollution issues and likeliness of testing manure P. However, 68% of farmers did not analyse manure P, indicating that mineral P fertiliser application rates were not adjusted accordingly, highlighting the risk of P being applied beyond crops’ requirement. Almost all farmers (96%) were willing to lower dietary P concentration but the uncertainty of P availability in feed ingredients (30%) and concerns over reduced cow fertility (22%) were primary barriers. The willingness to reduce dietary P concentrations was driven by the prospect of reducing environmental damage (28%) and feed costs (27%) and advice from their feed professionals (25%). Most farmers (70%) relied on a feed professional, and these farmers had a higher tendency to analyse their forage P. However, farmers of pasture-based systems relied less on feed professionals. Both farmers (73%) and feed advisers (68%) were unsatisfied with the amount of training on P management available. Therefore, the training on P management needs to be more available and the influence that feed professionals have over P feeding should be better utilised. Study findings demonstrate the importance of considering type of dairy farming systems when developing precision P feeding strategies and highlight the increasing importance of feed professionals in minimising P feeding.     

Dynamic spleen mass in wild and domestic American mink

The immune system is considered to be an energetically expensive component of an individual's life history. Investment in the immune system can depend on the environment that an individual finds itself in. The American mink, Neovison vison, exists in the natural environment and on fur farms. The natural environment and mink farm differ in many ways, such as wild mink being exposed to many parasites that are less prevalent and less abundant in the domestic environment because of veterinary care. We collected free‐ranging mink from commercial trappers and domestic mink from fur farmers in Ontario and Nova Scotia, Canada, and examined relative spleen mass. Wild male mink had larger spleens than domestic mink in Nova Scotia, with a similar trend in Ontario. Female mink that escaped from farms (feral) in Nova Scotia had significantly larger spleens than their domestic counterparts on the farms. Both of these results are consistent with the prediction that the natural environment contains parasites and pathogens that require enhanced investment in the immune system. In Nova Scotia, females had larger spleens than males, whether considering wild or domestic populations. Finally, wild mink showed greater condition dependence of spleen mass than domestic populations. Further investigations should include experimental approaches such as providing veterinary care to wild populations to assess the effects of parasites and pathogens on the immune system. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, 107 , 624–631.