Temperature is a key factor that shapes the distribution of organisms. Having knowledge about how species respond to temperature is relevant to devise strategies for addressing the impacts of climate change. Aquatic insects are particularly vulnerable to climate change, yet there is still much to learn about their ecology and distribution. In the Yungas ecoregion of Northwestern Argentina, cold-and warm-adapted species of the orders Ephemeroptera, Plecoptera, and Trichoptera(EPT) are segregated by elevation. We modeled the ecological niche of South American EPT species in this region using available data and projected their potential distribution in geographic space. Species were grouped based on their ecogeographic similarity, and we analyzed their replacement pattern along elevation gradients, focusing on the ecotone where opposing thermal preferences converge. Along this interface, we identified critical points where the combined incidence of cold and warm assemblages maximizes,indicating a significant transition zone. We found that the Montane Cloud Forest holds the interface, with a particularly greater suitability at its lower boundary. The main axis of the interface runs in a N-S direction and falls between 14℃-16℃ mean annual isotherms. The probability of a particular location within a basin being classified as part of the interface increases as Kira's warmth index approaches a score around 150. Understanding the interface is critical for defining the thermal limits of species distribution and designing biomonitoring programs. Changes in the location of thermal constants related to mountainous ecotones may cause vertical displacement of aquatic insects and vegetation communities. We have recognized significant temperature thresholds that serve as indicators of suitability for the interface. As global warming is anticipated to shift these indicators, we suggest using them to monitor the imprints of climate change on mountain ecosystems.

Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa farms using cross-sectional data from areas ranging from 190 to 1021 m above sea level which were classified as low, medium, and high elevation in Davao City, considered as the chocolate capital of the Philippines. Using stochastic frontier analysis, the results showed that the cost of inputs per ha and the number of cocoa trees per ha significantly increase yield. Farms at high elevations were less technically efficient, as this entails lower temperatures and increased rainfall, and cocoa farming in those areas and conditions can be more challenging, especially with changes in farming practices, terrain, and distance to markets. Other significant variables were age of cocoa farms, married farmers, and age of the farmers. Older farms may be more developed, farmers who are married benefit from their spouses being able to readily contribute as farm labor, and lastly, older farmers' inefficiency may likely stem from nonadaptation of newer farming practices. With an average technical efficiency of 0.61, 0.63, and 0.26 in low, medium, and high elevation areas, respectively, farmers therefore have an incentive to improve farm practices and consider topographical variations found in high elevation areas. Recommendations for the improvement of technical efficiency of cocoa farms are better connectivity to markets, enhancing farm practices, and continuation and improvement of government programs on cocoa with an added emphasis on research. For farmers in high elevation areas, mitigating solutions such as sustainable agriculture practices and ecolabelling are key to improving efficiency and minimizing the potential negative impact on upland farming systems. Moreover, such adaptation measures may also contribute to sustainability of cocoa farming in high elevation areas.

The snow cover over the Taurus Mountains affects water supply, agriculture, and hydropower generation in the region. In this study, we analyzed the monthly Snow Cover Extent(SCE) from November to April in the Central Taurus Mountains(Bolkar, Alada?lar, Tahtal? and Binbo?a Mountains) from 1981 to 2021. Linear trends of snow cover season(November to April) over the last 41 years showed decreases in SCE primarily at lower elevations. The downward trend in SCE was found to be more pronounced and statistically significant for only November and March. SCE in the Central Taurus Mountains has declined about-6.3% per decade for 2500-3000 m in November and about-6.0% per decade for 1000-1500 m and 3000+ m in March over the last 41 years. The loss of SCE has become evident since the 2000s, and the lowest negative anomalies in SCE have been observed in 2014, 2001, and 2007 in the last 41 years, which are consistent with an increase in air temperature and decreased precipitation. SCE was correlated with both mean temperature and precipitation, with temperature having a greater relative importance at all elevated gradients. Results showed that there is a strong linear relationship between SCE and the mean air temperature(r =-0.80) and precipitation(r = 0.44) for all elevated gradients during the snow season. The Arctic Oscillation(AO), the North Atlantic Oscillation(NAO), and the Mediterranean Oscillation(MO) winter indices were used to explain the year-to-year variability in SCE over the Central Taurus Mountains. The results showed that the inter-annual variability observed in the winter SCE on the Central Taurus Mountains was positively correlated with the phases of the winter AO, NAO and MO, especially below 2000 m elevation.

Boulder spacing in mountain rivers and near-wake flow zones within the boulder array is very useful for fish habitat and growth of aquatic organisms. The present study aims to investigate how the boulder array and spacing influence the near-bed flow structures in a gravel-bed stream. Boulders are staggered over a gravel-bed stream with three different inter-boulder spacing namely(a) large(b) medium and(c) small spacing. An acoustic Doppler velocimeter was used for flow measurements in a rectangular channel and the results were compared with those acquired from numerical simulation. The time-averaged velocity profiles at the near-wake flow zones of boulders experience maximum flow retardation which is an outcome of the boulder-induced form roughness. The ratio of velocity differences associated to form and skin roughness and its positive magnitude reveals the dominance of form roughness closest to the boulders. Form roughness computed is 1.75 to 2 times higher than the skin roughness at the near-wake flow region. In particular, the collective immobile boulders placed at different inter-boulder spacings developed high and low bed shear stresses closest to the boulders. The low bed shear stresses characterised by a secondary peak developed at the trough location of the boulders is attributed to the skin shear stress. Further, the spatial averaging of time-averaged flow quantities gives additional impetus to present an improved illustration of fluid shear stresses. The formation of form-induced shear stress is estimated to be 17% to 23% of doubleaveraged Reynolds shear stress and partially compensates for the damping of time-averaged Reynolds shear stress in the interfacial sub-layer. The quadrant analysis of spatial velocity fluctuations depicts that the form-induced shear stresses are dominant in the interfacial sub-layer and have no significance above the gravel-bed surface.