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In 2009, the ETC Group estimated that some 70% of the food that people globally consume originates in the ‘peasant food web’. This figure has been both embraced and critiqued, and more recent critiques have focussed on analysing farm productivity to offer some more precise estimates. Several analyses suggest that the proportion of small farms’ contributions to total food production is closer to one-third, arguing that the role of small food producers in food security are grossly exaggerated. We challenge this argument by re-tabulating the available farm productivity data to demonstrate that smaller farms continue to provide a significant proportion of food and are consistently more productive than their larger counterparts. We further posit that even our own interpretation falls short of estimating the full extent of small farms’ contributions, including non-monetary ones, like ecosystem services and community life, many of which run counter to the productivist model that drives large-scale industrial agriculture. We conclude that policies that support small farms are a global necessity for food security, as well as for transitions to more sustainable and more equitable food systems.

Extraction of underground minerals causes subsidence of the ground surface due to gravitational forces. The subsidence rate depends on the type of extracted ore, as well as its shape, thickness, and depth. Additionally, the embedding and overburden rock properties influence the time needed for the deformations to reach the surface. Using the results of geodetic deformation monitoring, which supply the information on pattern and magnitude of surface deformation, the performance of the mine may be evaluated. The monitoring can supply information on the actual rock mass behaviour during the operation and in many cases during the years after the mining operations have ceased. Geodetic methods of deformation monitoring supply information on the absolute and relative displacements (changes in position in a selected coordinate system) from which displacement and strain fields for the monitored object may be derived. Thus, geodetic measurements provide global information on absolute and relative displacements over large areas, either at discrete points or continuous in the space domain. The geodetic methods are affected by errors caused by atmospheric refraction and delay of electromagnetic signal. Since geodetic measurements allow for redundancy and statistical evaluation of the quality of the data, they generally provide reliable results. Usually, the designed accuracy of deformation measurements should allow for the detection of at least one third of the expected maximum deformations over the desired time span at the 95% probability level. In ground subsidence studies in mining areas, 10 mm accuracy at 95% level in both vertical and horizontal displacements is typically required. In the case of salt mines, the process of ground subsidence in viscous rock is slow; therefore, subsidence monitoring surveys may be performed once a year. In subsidence determination, two techniques are commonly used: leveling and satellite positioning. The satellite positioning technique is used to determine the 3D (horizontal coordinates and height) or 2D position of monitored points (only horizontal coordinates). When comparing the heights determined from satellite and leveling surveys, it has to be noted that the leveling heights are referred with respect to the geoid (orthometric heights), while heights determined from satellite surveys are referred with respect to the ellipsoid (ellipsoidal height). In the case of satellite surveys, the accuracy of horizontal position is typically 2–3 times better than vertical. The analysis of the optimal session duration lead to the conclusion that in order to achieve the sub-cm accuracy of horizontal coordinates at 95% confidence level, the satellite positioning session length using Global Positioning System (GPS) should be at least three hours long. In order to achieve the sub-cm accuracy of height coordinate at 95% confidence level in a single observation session, the GPS session length should be at least twelve hours long.

Three typical waste furniture boards (fiberboard, chipboard, and blockboard) were pretreated with phosphoric acid and hydrogen peroxide (PHP). The fractionation process of these feedstocks was attempted in order to harvest the cellulose-rich fraction for enzymatic hydrolysis and bioethanol conversion; further, lignin recovery was also considered in this process. The results indicated that 78.9–91.2% of the cellulose was recovered in the cellulose-rich fraction. The decreased crystallinity, which promoted the water retention capacity and enzyme accessibility, contributed greatly to the excellent hydrolysis performance of the cellulose-rich fraction. Therefore, rather high cellulose–glucose conversions of 83.3–98.0% were achieved by hydrolyzing the pretreated furniture boards, which allowed for harvesting 208–241 g of glucose from 1.0 kg of feedstocks. Correspondingly, 8.1–10.4 g/L of ethanol were obtained after 120 h of simultaneous saccharification and fermentation. The harvested lignin exhibited abundant carboxyl –OH groups (0.61–0.67 mmol g−1). In addition, approximately 15–26 g of harvested oligosaccharides were integrated during PHP pretreatment. It was shown that PHP pretreatment is feasible for these highly recalcitrant biomass board materials, which can diversify the bioproducts used in the integrated biorefinery concept.

The objective of this study is to investigate the impacts of the environmental and socio-economic risks on the fisheries in the Mediterranean region from an economic point of view. A balanced panel of 21 Mediterranean countries for 2001–2018 has been estimated by the GLS method, considering heteroskedasticity and correlation among cross sections. The volume of fish landed and landed values have been considered in two models. The results show that increases in sea bottom and surface temperature, H+ ion concentration and salinity threaten the fisheries in the Mediterranean region for the volume of fish landed and that sea surface temperature and salinity negatively influence landed values. In addition, there is an inverse U-shaped relationship between human population and fisheries. Moreover, the Human Development Index (HDI), an indicator of countries’ adaptive capacity, has a positive impact on fisheries and indicates that countries can safeguard fisheries by improving their adaptive capacity. Finally, our results strongly show the risk of climate change for the fisheries in the Mediterranean region and that fisheries are adversely impacted by climate change as well as worsening socio-economic conditions in the absence of adaptation plans.

The pigment content in leaves has commonly been used to characterize vegetation condition. However, few studies have assessed temporal changes of local biotic and abiotic factors on leaf pigments. Here, we evaluated the effect of local environmental variables and tree structural characteristics, in the chlorophyll-a leaf concentration (Chl-a) associated with temporal change in two mangrove species. Rhizophora mangle (R. mangle) and Avicennia germinans (A. germinans) trees of a fringe mangrove forest (FMF) and lower basin mangrove forest (BMF) were visited over a period of one year, to obtain radiometric readings at leaf level to estimate Chl-a. Measurements on tree characteristics included diameter at breast height (DBH), basal area (BA), and maximum height (H). Environmental variables included soil interstitial water temperature (Ti), salinity (Si), and dissolved oxygen (Oi), flood level (fL), ambient temperature (Tamb), and relative humidity (Hrel). Generalized linear models and covariance analysis showed that the variation of Chl-a is mainly influenced by the species, the interaction between species and mangrove forest type, DBH, seasonality and its influence on the species, soil conditions, and fL. Studies to assess spatial and temporal change on mangrove forests using the spectral characteristics of the trees should also consider the temporal variation of leave chlorophyll-a concentration.

Governance is recognized as a means to promote sustainable outcomes by democratizing the policy process and potentially harmonizing competing policy interests. This is particularly critical for sustainable tourism policy with its multiple sectors and multiple stakeholders at multiple scales. Yet little is known about the kinds of governance processes and instruments that are able to effectively harmonize competing power interests to better balance economic, ecological, and social concerns. This study analyzes the case of Bhutan and its Gross National Happiness (GNH) strategy as it is applied to sustainable tourism policy. Based on semi-structured interviews and focus groups with 57 state and non-state governance actors, it explores whether Bhutan’s unique GNH governance framework successfully harmonizes competing interests in the pursuit of sustainable tourism policy. It argues that the implementation of Bhutanese tourism policy is characterized by diverse and unexpected applications of power by multiple policy stakeholders. These complex power dynamics are not shaped in a meaningful way by the GNH governance instruments. Nor are they rooted in a common understanding of GNH itself. While this situation should subvert sustainable tourism policy, a commitment among state and non-state governance actors to a common set of Buddhist-infused cultural values shapes and constrains policy actions in a manner that promotes sustainable tourism outcomes.

This is a defining moment for the Great Lakes St Lawrence region, with the opportunity to renovate the regime for ecosystem improvement, protection and sustainability. The binational Great Lakes Water Quality Agreement was first signed in 1972. The outcome of a 2007 review of the Agreement by government and citizens, resulted in a broad call for and revisions to the Agreement, so that it can once again serve as a visionary document driving binational cooperation to address long-standing, new and emerging Great Lakes environmental issues in the 21st century. A prescription for renegotiating the Agreement to generate a revitalized and sustainable future mandates that science inform contemporary public policy, third Party Mediation presses for and coordinates a deliberate negotiation, and inclusive discourse and public engagement be integral through the process.