Search Results (7)

Microrefugia can be critical in mediating biological responses to climate change, but the location and characteristics of these habitats are often poorly understood. Groundwater-dependent ecosystems (GDEs) represent critical microrefugia for species dependent on cool, moist habitats. However, knowledge of the distribution and stability of GDE microrefugia remains limited. This challenge is typified in the Pacific Northwest, where poorly studied cliff-face seeps harbor exceptional biodiversity despite their diminutive size (e.g., ~1–10 m width). To improve knowledge about these microrefugia, we regionally modeled their distribution and stability. We searched for cliff-face seeps across 1608 km of roads, trails, and watercourses in Washington and Idaho, while monitoring water availability plus air and water temperatures at selected sites. We detected 457 seeps through an iterative process of surveying, modeling, ground-truthing, and then remodeling the spatial distribution of seeps using boosted regression trees. Additionally, we used linear and generalized linear models to identify factors linked to seep thermal and hydrologic stability. Seeps were generally most concentrated in steep and low-lying areas (e.g., edges of canyon bottoms), and were also positively associated with glacial drift, basalt or graywacke bedrock types, high average slope within 300 m, and low average vapor pressure deficit. North-facing slopes were the best predictor of stable air and water temperatures and perennial seep discharge; low-lying areas also predicted stable seep water temperatures. These findings improve possibilities to manage seep microrefugia in the Pacific Northwest and safeguard their associated biodiversity under climate change. Lastly, our iterative method adapts techniques commonly used in species distribution modeling to provide an innovative framework for identifying inconspicuous microrefugia. Full article

The urban heat island (UHI) effect has emerged as a growing ecological challenge in compact urban environments. Although urban vegetation plays a vital role in mitigating thermal extremes, its cooling performance varies depending on vegetation type and urban morphological context. This study explores the extent to which compact urban development—quantified using the Mixed-use and Intensive Development (MIXD) index—modulates the cooling responses of different vegetation types in Nanjing, China. A combination of landscape metrics, regression-based interaction models, and XGBoost with SHAP analysis is employed to uncover vegetation-specific and structure-sensitive cooling effects. The results indicate that densely planted trees exhibit reduced cooling effectiveness in compact areas, where spatial clustering and fragmentation tend to intensify UHI effects, particularly during nighttime. In contrast, scattered trees are found to maintain more stable cooling performance across varying degrees of urban compactness, while low-lying vegetation demonstrates limited thermal regulation capacity. Critical thresholds of MIXD (approximately 28 for UHI area and 37 for UHI intensity) are identified, indicating a nonlinear modulation of green space performance. These findings underscore the importance of vegetation structure and spatial configuration in shaping urban microclimates and offer mechanistic insights into plant–environment interactions under conditions of increasing urban density. Full article

Measurement of gas concentrations constitutes basic knowledge for the computation of emissions from livestock buildings. Although it is well known that hot climate conditions increase gas emissions, in the literature the relation between gas concentrations from open barns and animal-related parameters has not been investigated yet. This study aimed at filling this gap by evaluating daily gas concentrations within an open-sided barn in hot Mediterranean climate. The influence of microclimatic parameters (MC) and cow behavior and barn management (CBBM) were evaluated for ammonia (NH₃), methane (CH₄), and carbon dioxide (CO₂) concentrations. Results showed that both MC and CBBM affected concentrations of NH₃ (p < 0.02), CH₄ (p < 0.001), and CO₂ (p < 0.001). Higher values of NH₃ concentration were detected during the cleaning of the floor by a tractor with scraper, whereas the lowest NH₃ concentrations were recorded during animal lying behavior. Measured values of CO₂ and CH₄ were highly correlated (C = 0.87–0.89) due to the same sources of production (i.e., digestion and respiration). The different management of the cooling systems during the two observation periods reduced significantly CH₄ concentrations in the barn when the cooling system in the feeding area was switched off. Based on methodological choices due to the specific barn typology, parameters related to animals can provide information on the variation of gas concentrations in the barn environment in hot climate conditions. Full article

The rearing of piglets is a demanding phase of pig production partly because of the changing temperature requirements of the piglets during rearing. Piglets need high temperatures in the resting area, especially at the beginning, while the optimal temperature is lower toward the end of rearing. To meet the changing temperature demands of the piglets and also to optimize the pen structure, one floor cooling and two heating systems were examined in this study. In two rearing compartments, four pens with 48 piglets each were equipped with a heated cover above a heated/cooled lying area. The lying behavior and performance of 1152 piglets, in addition to the pen fouling, were recorded over six rearing periods. There was no difference between the two heating systems in the lying behavior. However, the acceptance of the lying area was very high in all pens and periods with heating. The cooling had a significant influence on the lying behavior depending on the rearing week. Significantly more piglets lay on the cooled lying area compared with the control pen during the last weeks. The fouling of the pens was not affected by the cooling or heating systems; however, the fouling in all pens was very low. The tested pen structure in combination with a heating and cooling system is a well-functioning way of integrating a solid lying area. Full article

The Zhuguangshan complex hosts the main uranium production area in South China. We report (U-Th)/He and fission track thermochronological data from Triassic–Jurassic mineralized and non-mineralized granites and overlying Cambrian and Cretaceous sandstone units from the Lujing uranium ore field (LUOF) to constrain the upper crustal tectono-thermal evolution of the central Zhuguangshan complex. Two Cambrian sandstones yield reproducible zircon (U-Th)/He (ZHe) ages of 133–106 Ma and low effective uranium (eU) content (270–776 ppm). One Upper Cretaceous sandstone and seven Mesozoic granites are characterized by significant variability in ZHe ages (154–83 Ma and 167–36 Ma, respectively), which show a negative relationship with eU content (244–1098 ppm and 402–4615 ppm), suggesting that the observed age dispersion can be attributed to the effect of radiation damage accumulation on ⁴He diffusion. Correspondence between ZHe ages from sandstones and granites indicates that surrounding sedimentary rocks and igneous intrusions supplied sediment to the Cretaceous–Paleogene Fengzhou Basin lying adjacent to the LUOF. The concordance of apatite fission track (AFT) central ages (61–54 Ma) and unimodal distributions of confined track lengths of five samples from different rock units suggest that both sandstone and granite samples experienced a similar cooling history throughout the entire apatite partial annealing zone (~110–60 °C). Apatite (U-Th-Sm)/He (AHe) ages from six non-mineralized samples range from 67 to 19 Ma, with no apparent correlation to eU content (2–78 ppm). Thermal history modeling of data suggests that the LUOF experienced relatively rapid Early Cretaceous cooling. In most samples, this was followed by the latest Early Cretaceous–Late Cretaceous reheating and subsequent latest Late Cretaceous–Recent cooling to surface temperatures. This history is considered as a response to the transmission of far-field stresses, involving alternating periods of regional compression and extension, related to paleo-Pacific plate subduction and subsequent rollback followed by Late Paleogene–Recent India–Asia collision and associated uplift and eastward extrusion of the Tibetan Plateau. Thermal history models are consistent with the Fengzhou Basin having been significantly more extensive in the Late Cretaceous–Early Paleogene, covering much of the LUOF. Uranium ore bodies which may have formed prior to the Late Cretaceous may have been eroded by as much as ~1.2 to 4.8 km during the latest Late Cretaceous–Recent denudation. Full article

Increasing demands on animal welfare and the higher temperatures in summer due to climate change make it necessary to adapt conventional pig husbandry systems. A cooled, solid lying area has the potential to increase lying comfort and reduce the heat stress, which improves animal welfare. In the present study, the effect of a cooled, solid lying area on lying and elimination behavior was investigated. In two fattening compartments, eight pens with 28 pigs each were rebuilt. Two pen designs, different in feeder place and type, were tested. The floor was cooled from 24.5 to 20 °C by cool water in half of the pens. A total of 672 fattening pigs were tested over three fattening periods. The lying behavior was recorded by video analysis three times per week and three times per day. In the pens with a cooled lying area, 14% (SED 2.9; p = 0.002), respectively 12% (SED 0.9; p = 0.0382) more pigs were lying on the solid lying area. Additionally, the fouling of the animals was reduced by the cooling in one pen design; the results were derived from weekly scores (0.42 vs. 0.67; SED 0.058 p = 0.0006). The fouling of the pen was not affected by the floor cooling, however, the fouling in all pens was very low. Full article

Landsat images from 1979, 1988, 1999, 2008, and 2013 were used to analyze the landscape area change of salt pans lying on the coast of Tianjin. While initially (1979–1988), the area of Tianjin’s salt pan increased, later (1988–2013) it declined dramatically. In the first phase (1979–1988) of the studied period the primary roll-in landscape of the salt pan wasbarren land with an area of 60.0 km². By 1988, the area of Tianjin’s salt pan rose to 457.8 km². The main roll-out landscape of the salt pan during 1988–2013 was urban, barren land, village/town, harbor, and road whose area amounted to 69.8, 35.9, 27.3, 25.5 and 18.4 km² respectively. The roll-out barren land will be transformed to construction land ultimately. By 2013, the total loss reached 167.3 km², which was 36.5% of the salt pan area of Tianjin in 1988. With the development of coastal economy, the salterns with a lower economic value were transformed to and replaced by land use types with a higher economic value. This trend would influence the production of sea salt and the development of sodium hydroxide and sodium carbonate industries. Seawater desalination provides an opportunity for the restoration and compensation of salt production capacity. Based on the theory of circular economy and industrial symbiosis, in this article an industrial symbiosis model for sea salt production and sea water desalination is explored: “mariculture–power plant cooling–seawater desalination–Artemia culture–bromide extraction–sea salt production–salt chemical industry”. Through the application of this process sustainable development of the sea salt production in Tianjin could be achieved. Full article