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The Cerrado biome is Brazil's breadbasket and a major provider of ecosystem services, though these dual roles are increasingly at odds, in part because there are few mechanisms to protect remaining vegetation from large‐scale agricultural expansion. We assessed Cerrado conversion to soy using over 580,000 property boundaries, covering 77% of the biome that is eligible for commercial land use, and using microwatersheds, to cover 100% of eligible areas. Soy expansion accounted for 22% of conversion during 2003–14. Only 15% of clearing exceeded restrictions on private properties under the Forest Code (FC). However, 51% of soy farms have violated the FC, five times the rate of other farms. As a leading cause of both Cerrado conversion and FC violations, the soy sector has environmental and economic incentives to shift production to already cleared land. We used suitability maps to identify potential pathways for soy expansion across both old and new cropland frontiers.

The depletion of natural resources and the increasing interest in reducing CO2 emissions have heightened the demand for alternative materials in concrete production. A viable approach is to lower the clinker-to-cementitious materials ratio by partially replacing clinker with supplementary cementitious materials (SCMs) and/or alternative materials such as aggregate mineral fillers (AMFs). As the availability of SCMs is expected to decline, AMFs have been increasingly explored, including those derived from aggregate processing and susceptible to alkali-aggregate reaction (AAR). However, the behaviour of AAR-reactive AMFs in concrete remains poorly understood. This paper summarizes the current state of the art and identifies knowledge gaps concerning the use of AAR-reactive AMFs, focusing on the roles of mineralogy, particle size, replacement content, and the test methods used to assess AAR-induced development and associated microscopic and mechanical deterioration. A consistent terminology is also proposed to support future research. Finally, a theoretical foundation to understand the role of AAR-reactive AMFs in mortar and concrete is provided, and the key knowledge gaps are discussed.

Brazil faces an enormous challenge to implement its revised Forest Code. Despite big losses for the environment, the law introduces new mechanisms to facilitate compliance and foster payment for ecosystem services (PES). The most promising of these is a market for trading forest certificates (CRAs) that allows landowners to offset their restoration obligations by paying for maintaining native vegetation elsewhere. We analyzed the economic potential for the emerging CRA market in Brazil and its implications for PES programs. Results indicate a potential market for trading 4.2 Mha of CRAs with a gross value of US$ 9.2±2.4 billion, with main regional markets forming in the states of Mato Grosso and São Paulo. This would be the largest market for trading forests in the world. Overall, the potential supply of CRAs in Brazilian states exceeds demand, creating an opportunity for additional PES programs to use the CRA market. This expanded market could provide not only monetary incentives to conserve native vegetation, but also environmental co-benefits by fostering PES programs focused on biodiversity, water conservation, and climate regulation. Effective implementation of the Forest Code will be vital to the success of this market and this hurdle brings uncertainty into the market. Long-term commitment, both within Brazil and abroad, will be essential to overcome the many challenges ahead.

Lime-pozzolan mortars are often used in restoration of historical buildings. In this paper pastes prepared with hydrated lime and metakaolin from kaolin production wastes were examined in order to verify the performance of this waste as a pozzolanic material in mixes containing hydrated lime. Some specimens were cured in moist air and some in dry air. The compositions and microstructures at curing times up to 180 d were assessed using thermal gravimetric analysis, X-ray diffraction and scanning electron microscopy. The major phases found in the lime-metakaolin pastes were strätlingite (C 2 ASH 8 ), monocarboaluminate (C 4 A C ¯ H 11 ), portlandite (CH) and calcite (C C ¯ ). The phases formed in these pastes were affected by curing conditions. In the moist cured samples the main phase was strätlingite and in the dry cured samples the main phase was monocarboaluminate. The portlandite was consumed by 28 d in moist curing and by 180 d in dry curing. SEM images showed that the morphology of lime-metakaolin pastes was influenced by curing condition and metakaolin content. In the moistured samples the morphologies of the main phases appeared very well formed with sharp edges, whereas in the dry cured samples the morphologies did not appear very well formed. This work shows that pastes using metakaolin made from kaolin production wastes had similar microstructural characteristics as have been reported for pastes made using commercial metakaolin. So this metakaolin is a suitable and environmentally friendly pozzolanic material for use in lime mortars.

The accelerated development of construction has positively boosted the economy but caused environmental pollution. The objective of this article was to propose a model to quantify and identify the causes of environmental aspects in urban infrastructure projects during the pre-construction phase. The methodology included ten environmental aspects and six construction activities, distributed in three phases: quantification, preparation of an inventory and identification of the main causes of environmental aspects. The results of projects A, B and C confirmed five environmental aspects with quantifications of the maximum normalized unitary ratios, namely greenhouse gas emissions with 1.00, 1.00 and 1.00; energy use with 0.99, 0.99 and 1.00; noise pollution with 0.84, 0.89 and 1.00; water use with 0.95, 1.00 and 0.96 and use of resources and raw materials with 1.00, 1.00 and 1.00, caused by the construction methods, machines, materials and environmental conditions of the urban infrastructure project. This proposal was the first initiative to analytically and previously investigate the environmental performance of future infrastructure works, assisting in the strategies of the pre-construction phase and improving the decision-making process regarding environmental issues in constructions. Finally, this initial effort may evolve to create opportunities to avoid, mitigate, reduce or accept the environmental effects in the infrastructure projects in developing countries.

Brazil's controversial new Forest Code grants amnesty to illegal deforesters, but creates new mechanisms for forest conservation. Roughly 53% of Brazil's native vegetation occurs on private properties. Native forests and savannahs on these lands store 105 ± 21 GtCO 2 e (billion tons of CO 2 equivalents) and play a vital role in maintaining a broad range of ecosystem services ( 1 ). Sound management of these private landscapes is critical if global efforts to mitigate climate change are to succeed. Recent approval of controversial revisions to Brazil's Forest Code (FC)—the central piece of legislation regulating land use and management on private properties—may therefore have global consequences. Here, we quantify changes resulting from the FC revisions in terms of environmental obligations and rights granted to land-owners. We then discuss conservation opportunities arising from new policy mechanisms in the FC and challenges for its implementation.

Global temperatures have led to an increasing need for air conditioning systems. So, because of this fact, buildings have been improved in terms of their thermal and energy efficiency. Regarding this, the Brazilian standard ABNT NBR 15.575-4/2013 set minimum parameters for the thermal transmittance and thermal capacity of sealing elements, which allow classifying the thermal efficiency of the building. In order to comply with the requirements, the usage and study of lightweight construction materials have been in focus. An example of these materials is vermiculite. The present research reviewed articles about expanded vermiculite. The study involved the examination and comparison of various articles to analyze the properties of vermiculite and the impact of its usage on coating mortars. It was possible to verify that using vermiculite in mortars caused bad workability and a decrease in mechanical strength. However, the porosity and water absorption in mortars increased. Additionally, it reduced the specific weight and the thermal conductivity of the mortars, allowing for a better thermal insulation of the rooms. As an alternative to decreasing the negative effects of vermiculite, it is possible to use chemical admixtures, mineral additions, and mix design with a greater consumption of binder or a combination of particle sizes.

Many works have shown that metakaolin is very good pozzolanic material for using in lime mortars and Portland cement mortars. Alternatively, many studies also have shown that kaolin wastes, after some treatment, can become a high quality pozzolans. Most of these studies have discussed about the microstructural characteristics and hardened properties of pastes, mortars or concretes mixes containing metakaolin or kaolin wastes cured in moist environment. In this work pastes and mortars made of metakaolin and hydrated lime (L-MK), which the metakaolin was obtained from the kaolin production waste, were assessed in their hardened state. Two curing conditions were considered: dry and moist environment; and three ages of curing (28, 90 and 180 days) were studied. Pastes were assessed by XRD and TG/DTG. In pastes according to the XRD and TG/DTG results, the main hydrated products found were strätlingite, in moist curing, and monocarboaluminate, in dry curing. Properties like flexural and compressive strengths, water absorbed capillarity and loss mass variation were studied in mortars. The results showed that mortars in dry curing presented lower strengths than one in moist curing. In moist curing mortars presented compressive strength values around 12 MPa and in dry curing this value reached 6 MPa. This fact indicate that the strätlingite maybe is responsible for the high strengths in mortars in moist curing when compares with the strengths of mortars cured in dry environment. Further the results showed that mortars in dry curing presented higher water absorbed and mass loss variation than mortars in moist curing.

Conserving natural vegetation cover is of critical importance for maintaining the ecological integrity and hydrological properties of large river basins (more than 100 000 km2). Recent estimates indicate that more than 700 000 km2 of Brazilian Amazon have already been deforested, and to reduce further losses and preserve the important natural and cultural resources in this region, large conservation areas have been created by the Brazilian government. The present study analysed land cover and land use change in the major watersheds of the Brazilian Amazon, in order to evaluate the current balance between deforestation and conservation of natural areas in the region. The results show that watersheds draining the southern part of the basin have suffered the highest deforestation rates, with the largest losses (8.3–20% of total basin area) occurring in the Madeira, Tapajós, Xingu, Araguaia and Tocantins river basins. Most large watersheds already have significant deforestation in their headwaters, which can affect hydrological functions and ecological sustainability. The greatest allocation of land for conservation was encountered in the Trombetas, Xingu and Negro watersheds, where conservation areas occupied 92.5, 56.9 and 50.6% of the total basin, respectively. While extensive areas of the Amazon biome have been deforested, on the scale of large watersheds there is a positive balance between conservation areas and deforestation, and on average the area delimited by conservation areas is more than three times larger than the deforested areas. An analysis by subwatersheds, however, indicates that certain regions have achieved more critical levels of deforestation, in some situations affecting more than 80% of the subwatersheds.