Multicriteria spatial model to prioritize degraded areas for landscape restoration through agroforestry.

Reconciling the restoration of ecosystem services within agricultural landscapes is an effort that has been advancing within degraded areas restoration through agroforestry systems. However, to contribute to the effectiveness of these initiatives, it is essential to integrate landscape vulnerability and local demands to better highlight in which areas the implementation of agroforestry systems should be prioritized. Thus, we developed a spatial hierarchization methodology as a decision support tool as an active strategy for agroecosystem restoration. The proposed method constitutes a spatial indicator of priority areas to guide agroforestry interventions, including resource allocation and public policies for payment for environmental services. The methodology consists of Multicriteria Decision Analysis implemented in GIS software by combining input datasets based on biophysical conditions, environmental and socioeconomic aspects, that integrated promotes an assessment of the environment fragility, the pressures and responses to land use dynamic; a strategy for landscape restoration and conservation of the natural habitats, and multiple specific scenarios for decision making regarding the agricultural and the local actors demands. The output of the model provides the spatial distribution of areas suitable for the implementation of agroforestry systems, sorted into four priority levels (Low, Medium, High, and Extreme priority). The method is a promising tool proposal for territorial management and governance and subsidizes future research on the flows of ecosystem services.•Assessment of the environment fragility and the pressures and responses to land use dynamic.•Strategy for landscape restoration and conservation of remaining natural habitats.•Multiple specific scenarios for decision making regarding the agricultural and the local actors demands.

Spatial indicator of priority areas for the implementation of agroforestry systems: An optimization strategy for agricultural landscapes restoration.

The ecological functions restoration in agricultural areas is a major challenge on a landscape scale. In the specific case of active restoration through Agroforestry Systems (AFS), the absence of a specific direction hinders ecological restoration processes, especially in regions that prefer intensive agriculture. Thus, this study aims to develop a Spatial Indicator of Priority Areas to guide Agroforestry Systems implementation in agricultural landscapes. A spatial multicriteria decision analysis (MDCA) was carried out based on environmental factors: soil, geology and slope (which determine the natural vulnerability of the land) and anthropogenic factors: land use and land cover, forest fragments, potential land use capacity and legal protected areas in rural properties (which reflects human pressure and land use suitability). Subsequently, four priority levels were classified for agroforestry interventions: (1) Low priority; (2) Average priority; (3) High priority; (4) Extreme priority. A final map was made to identify priority areas for landscape recovery in 9 cities located at the mouth of the Mogi Guaçu River Hydrographic Basin, State of São Paulo, Brazil. Considering the natural vulnerability of the land and the multifunctional aspects of the landscape, the scenarios projection allowed a consensus for forest conservation and agricultural suitability perspectives. A final combination of the explored aspects culminated in the spatial indicator, which model foresees 22,300 ha available for urgent actions for restoration, reforestation and sustainable exploitation through agroforestry systems. We emphasize the challenges in reconciling the socioeconomic and ecological functions in the agroecosystem, however, the metric provides a more inclusive and assertive management strategy for natural resources and advances towards the goal of reforestation and implementation of payment for environmental services (PES) schemes.

A case study of factors controlling water quality in two warm monomictic tropical reservoirs located in contrasting agricultural watersheds.

The integration of internal (e.g., stratification) and external (e.g., pollution) factors on a comprehensive assessment of reservoir water quality determines the success of ecosystem restoration initiatives and aids watershed management. However, integrated analyses are scarcer than studies addressing factors separately. Integration is likely more efficient in studies of small well-characterized (experimental) reservoir watersheds, because the isolation of factor contributions is presumably clearer. But those studies are uncommon. This work describes the water quality of two small 5.5 m-deep reservoirs (MD-Main and VD-Voçoroca dams) located in Pindorama Experimental Center, state of São Paulo, Brazil, considering the interplay between reservoir dimension, seasonal thermal stratification, chemical gradients, erosive rainfall events, presence of natural biofilters, and land uses and landscape patterns around the reservoirs and within the contributing watersheds. The monitoring of agricultural activities and water quality parameters occurred in October 2018-July 2019. A 4 °C thermal stratification occurred in October (difference between surface and bottom water temperature), which decreased until disappearance in January (VD) or April (MD). The longer stratification period of MD was justified by its larger area relative to VD (≈10×). Thermal stratification triggered hypoxia at the bottom of both reservoirs (DO ≈ 1 mg/L), more prolonged and severe in MD. Hypoxia activated Ec and TDS peaks in January likely explained by bottom-sediment nutrient releases, presumably phosphorus. The Ec peak reached 560 µS/cm in MD and 290 µS/cm in VD. The smaller VD peak was probably explained by the action of macrophytes. In March, a 240 NTU turbidity peak occurred in MD, caused by precedent erosive rainfall and the lack of vegetation protection alongside the south border. As expected, the study accomplished clear isolation of factor contributions, verified by Factor and Cluster analyses. Our results can subsidize studies on larger reservoir watersheds requiring restoration, where the isolation of factors is more challenging.

Conflito de uso e indicadores morfométricos para a gestão de política de uso do solo / Land use conflict and morphometric indicators for land use policy management

RESUMO Este trabalho propõe indicadores ambientais de políticas públicas com base na espacialização dos parâmetros morfométricos e de conflito de uso em áreas municipais. As técnicas de geoprocessamento de imagens orbitais em sistemas de informações geográficas foram utilizadas para analisar o banco de dados dos valores de cada parâmetro morfométrico da superfície terrestre - área, perímetro, comprimento da rede de drenagem, densidade de drenagem, número de canais, frequência de rios, declividade e coeficiente de rugosidade - e elaborar os mapas temáticos de uso atual, de uso potencial e de conflito de uso do solo. Os dados foram submetidos à análise estatística descritiva e exploratória multivariada. A espacialização dos valores obtidos da caracterização morfométrica gerou indicadores físicos ambientais que possibilitaram a diferenciação de áreas. O conhecimento do sistema hidrológico dessas regiões reflete o sistema natural de drenagem em seu comprimento. O número de canais e conflito de uso indicam áreas prioritárias para gestão ambiental e políticas de uso do solo. Os parâmetros morfométricos são potenciais indicadores ambientais.

ABSTRACT This study has the main objective to propose environmental indicators for public policies based on spatial distribution of morphometric characteristics and land-use conflicts in municipal areas. The techniques of satellite images in geographic information systems were used to analyze the database of the values of each morphometric parameter of the earth's surface: area, perimeter, length of the drainage system, drainage density, number of channels, river frequency, slope and roughness coefficient and to elaborate thematic maps of current land-use, potential land-use, and land-use conflicts. The data were submitted to descriptive and multivariate exploratory statistical analysis. The spatial distribution of values of morphometric characterization generated environmental physical indicators which enabled the differentiation of areas. The knowledge of the hydrological system in these regions reflects the natural drainage system along its length. The number of channels and the land-use conflicts indicate priority areas for environmental management and land use policies. The morphometric characteristics are potential environmental indicators.