Vegetation cover as an indicator for effective implementation of land use regulations in Sardinia

Land degradation is a worldwide issue which is often closely linked to human activity. In semi-arid environments common degradation processes are due to excessive soil losses, gully formation, surface sealing, and soil moisture depletion. Forest fire is increasingly an additional problem in the dry areas. In the present study, human interactions with land degradation are studied in a case study in Sardinia, Italy. Land degradation risk assessment was carried out using a desertification indicator method, the obtained result of which shows the prominent effect of vegetation cover. In the study area, high land degradation risk (and low vegetation cover) is found mostly in rainfed cultivation, overgrazed areas and those parts covered by olive groves or vineyards. Various strategies have been implemented, both deliberately and as a result of circumstantial effects, to alter vegetation cover over time. In the analysis, time series Normalized Difference Vegetation Index (NDVI) data was used for the period 1972 to 2009. Results show that not all human interactions with the environment are necessarily negative. The improvement of vegetation cover on the island is mainly due to good implementation of land use regulations. Three main factors seem to be responsible for the increase in vegetation cover: (1) government implementation policy on land uses; (2) reforestation in the over-grazed area; (3) the migration of the youngest generation of the population from the country side to the urban areas. The study demonstrates that vegetation cover on the island is improving as compared to the past, decreasing the land degradation risk even though the region is coping with climate change

VISITOR PREFERENCES AND VALUES FOR WATER-BASED RECREATION: A CASE STUDY OF THE OCALA NATIONAL FOREST

We used the open-ended contingent valuation method to elicit willingnes to pay (WTP) for day visitors and extended visitors on the Ocala National Forest (ONF), Florida. A Tobit model specification was applied to account for the issues involved with censored WTP bids. The results reveal that visitors would pay more for improved recreational facilities at the ONF. In particular, our estimates show that visitors would pay $1 million for basic facilities,$1.9 million for moderate improvements, and $2.5 million for more improvements.contingent valuation, Tobit analysis, water-based recreation, Resource /Energy Economics and Policy, Q23, Q26,

Style Transfer to Calvin and Hobbes comics using Stable Diffusion

This project report summarizes our journey to perform stable diffusion fine-tuning on a dataset containing Calvin and Hobbes comics. The purpose is to convert any given input image into the comic style of Calvin and Hobbes, essentially performing style transfer. We train stable-diffusion-v1.5 using Low Rank Adaptation (LoRA) to efficiently speed up the fine-tuning process. The diffusion itself is handled by a Variational Autoencoder (VAE), which is a U-net. Our results were visually appealing for the amount of training time and the quality of input data that went into training.Comment: Project report for ECE 371Q Digital Image Processing at UT Austi

The influence of soils on heterotrophic respiration exerts a strong control on net ecosystem productivity in seasonally dry Amazonian forests

Net ecosystem productivity of carbon (NEP) in seasonally dry forests of the Amazon varies greatly between sites with similar precipitation patterns. Correctly modeling the NEP seasonality with terrestrial ecosystem models has proven difficult. Previous modelling studies have mostly advocated for incorporating processes that act to reduce water stress on gross primary productivity (GPP) during the dry season, such as deep soils and roots, plant-mediated hydraulic redistribution of soil moisture, and increased dry season leaf litter generation which reduces leaf age and thus increases photosynthetic capacity. Recent observations, however, indicate that seasonality in heterotrophic respiration also contributes to the observed seasonal cycle of NEP. Here, we use the dynamic vegetation model CLASS-CTEM (Canadian Land Surface Scheme–Canadian Terrestrial Ecosystem Model) – without deep soils or roots, hydraulic redistribution of soil moisture, or increased dry season litter generation – at two Large-Scale Biosphere–Atmosphere Experiment (LBA) sites (Tapajós km 83 and Jarú Reserve). These LBA sites exhibit opposite seasonal NEP cycles despite reasonably similar meteorological conditions. Our simulations are able to reproduce the observed NEP seasonality at both sites. Simulated GPP, heterotrophic respiration, latent and sensible heat fluxes, litter fall rate, soil moisture and temperature, and basic vegetation state are also compared with available observation-based estimates which provide confidence that overall the model behaves realistically at the two sites. Our results indicate that representing the effect of soil moisture on heterotrophic respiration in terms of soil matric potential and constraining heterotrophic respiration when absolute soil matric potential is both low (wetter soils) and high (drier soils), with optimum conditions in between, allows %appropriately representing the influence of soil texture and depth, %through soil moisture, on seasonal patterns of GPP and, especially, % heterotrophic respiration is important to correctly simulate NEP seasonality