Forty eight and ninety six pigs weaned at 22.6 f 2.6 days, were allocated to two trials to study the effect of feeding post-weaning diets ad libitum, either as dry pellets (DF) or as meal mixed with water in the ratio 2.5 : 1 (LF). The trials, lasting 28 days, differed only in the type of trough used to present the liquid feed to the pigs. In both trials the daily gain of LF pigs over the 4 weeks of the trial was significantly ( P < 0.001) better than that of the D F pigs. Daily gains for the two treatment groups were respectively 428 and 343 15 g day-' in Trial 1 and 454 and 397 k 10 g day-' in Trial 2. The feed conversion ratio (FCR) (corrected to fresh weight of dry feed) of LF pigs was significantly poorer ( P < 0.01) than that of D F pigs in both trials primarily as a result of feed wastage by the LF pigs. FCR for the D F and LF pigs was, respectively, 1.31 and 1.89 & 0-05 in Trial 1. In Trial 2 improvements in the trough design reduced the difference in FCR. FCR for the D F and LF treatments was 1.37 and 1.44 f 0.02 respectively. In Trials 1 and 2 LF pigs used on average 76% and 35% more water than D F pigs. LF pig produced 12% (Trial 1) and 5.7% (Trial 2) more effluent per unit of liveweight gain than D F pigs. Microbiological examination of the liquid feed system demonstrated that the system acted as a fermenter. Lactobacillus spp proliferated rapidly and became the dominant organism within 5 days and the populations remained relatively constant thereafter. The proliferation of lactobacilli reduced the pH of the liquid feed from approximately 6.0 to between 3.5 and 4.0. At the lower levels of pH the number of coliforms in the feed was significantly reduced.

-The choice of cultivation system in arable agriculture exerts a strong influence not only on soil health and crop productivity but also on the wider environment. Conservation tillage using non-inversion methods conserves soil carbon, reduces erosion risk and enhances soil quality. In addition, conservation tillage has been shown to sequester more carbon within the soil than inversion tillage, reducing carbon dioxide losses to the atmosphere. Stable, well structured topsoils that develop following long-term conservation tillage lead to more energy efficient systems due to the reduced power requirements for cultivation. Long-term experiments, e.g. more than 20 years, that confirm the impact of conservation tillage over an extended period are not common. Here we evaluate the impact of different tillage methods and winter wheat straw management, either incorporated or removed, on organic matter turnover and soil quality indicators. No-till, chisel and mouldboard ploughing was carried out for 23 years on a silty clay loam soil in South West England that was not considered suitable for non-inversion tillage due to weak soil structure. In order to assess the effect of contrasting cultivation and straw disposal method on soil carbon dynamics, a range of assays were conducted, including water extractable organic carbon, hot water extractable carbohydrate, microbial biomass carbon, activity of β-glucosidase and acid phosphatase enzymes, C sequestration and the natural abundance of 13 C. Our results show that the soil organic carbon concentration in the topsoil was greater under no-till than mouldboard ploughing, while a reverse trend was observed in the lower depths. A 14-17% increase in soil organic carbon was observed in the topsoil for chisel plough and no-till treatments compared to mouldboard ploughing. Water extractable organic carbon was found to constitute only 1-7% of the microbial biomass carbon. Hot water extractable carbohydrate was one of the most sensitive indicators of soil quality and had a significant a negative correlation with bulk density and positive correlation with soil organic carbon microbial biomass carbon β-glucosidase and acid phosphatase. The choice of cultivation method exerted a major control on microbial and carbon dynamics. No-till and chisel ploughing maintained carbon in the soil surface horizons, which will benefit the stability of this weakly structured soil, but mouldboard ploughing distributed carbon more uniformly throughout the soil profile, particularly when straw was incorporated, hence leading to the retention of more carbon in the soil profile. soil quality / carbon sequestration / tillage / straw management / winter wheat

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Having a healthy built environment becomes increasingly important, especially under the effects of COVID-19. This paper intends to combine sustainable goals based on climate change with passive design principles to achieve a healthy built environment regarding the building performance of residential buildings. The Yuedao Residential Community in the Lingnan area was taken as an example for the research. Based on relevant standards of healthy buildings, the thermal, light, and acoustic environment requirements were determined. The methods of building performance simulation and on-site measurement were used to quantify the research object environments. Then, the outcomes were obtained based on these standards. As observed, the thermal environment’s adaptive thermal comfort level was level III. It was hot indoors, but the light and acoustic environments met the requirements. Building designs based on a built environment optimized by external shading systems aim to solve problems through building performance simulation and qualitative analysis. After optimization, the thermal environment improved. According to the literature review, this research focused on a healthy built environment with a sustainable passive design in terms of building performance. A research workflow was established that could be used for more practical research, with abundant research methods. The problems were solved to varying degrees, and the Lingnan architectural culture was preserved. Moreover, this research filled the gap in interactive research on healthy built environments with sustainable passive design regarding building performance.