Science of forests and floods: The quantum leap forward needed, literally and metaphorically

A century of research has generated considerable disagreement on the effect of forests on floods. Here we call for a causal inference framework to advance the science and management of the effect of any forest or its removal on flood severity and frequency. The causes of floods are multiple and chancy and, hence, can only be investigated via a probabilistic approach. We use the stochastic hydrology literature to infer a blueprint framework which could guide future research on the understanding and prediction of the effects of forests on floods in environments where rain is the dominant form of precipitation. Drawing parallels from other disciplines, we show that the introduction of probability in forest hydrology could stimulate a gestalt switch in the science of forests and floods. In light of increasing flood risk caused by climate change, this probabilistic framework can help policymakers develop robust forest and water management plans based on a defensible and clear understanding of floods.

Examining inequities in species loss due to land use in China from an interregional trade perspective

The escalating impact of land use pressures indicates we've exceeded the proposed safe planetary boundary. Economic shifts and increased trade drive China's demand for agricultural and forestry products, land-use changes, and subsequent biodiversity damage often occur far from where they are consumed. Given many species in China are endemic or endangered, neglecting these interconnected economic trends threatens its biodiversity conservation targets. Here, we first quantify species loss due to six land use types embodied in the life cycle at the Chinese sub-national level. Then, a Chinese high-resolution multi-regional input-output (MRIO) model was used to link threatened species to key industrial sectors in the supply chain, tracking the spatiotemporal patterns of land use species loss embodied in Chinese trade from 2007 to 2017. Our results reveal a 6% increase in aggregated species loss in China during the study period. This subtle change in species loss footprints in recent years is partially due to increases in consumption levels being offset by reductions in species loss intensity, though drivers vary by region. Notably, the Northwest and Southwest, known for their high species richness, suffer the greatest inequalities in species loss. The domestic species loss transfer most apparent in the outsourcing from the Eastern Coast to the Southwest. The Southwest registered the highest territory-based species loss, particularly for amphibians, while the highest impacts in the supply chain are associated with Forestry, logging, and related activities. Our analysis underscores the need for enhanced provincial dialogue to systematically value and monitor biodiversity, a key natural capital, and encourage its conservation. Our study effectively monitors the consumption-based species losses across China, which can further improve knowledge and dialogue on ecological challenges associated with trade.

Evaluating impacts of paper and electronic billing and invoicing business systems from an environmental and energy perspective

The environmental and energy impacts of ICT were identified using a comparative life cycle assessment (CompLCA) focused on business invoicing processes comparing online to paper processes. There were net energy benefits from online billing. The potential impact across the economy and society is large, particularly as COVID-19 has forced many businesses and government services to shift to online service provision. For one million bills produced electronically and received by customers instead of a paper bill, 18.9 t CO2e is avoided, which translates to a national saving of 22,680 tCO2e, assuming 1.2 billion annual invoicing transactions. The impacts of CO2 are sensitive, however, to several assumptions. The study's originality was to show the range of invoicing variables that impact energy and the environment and to highlight which ones can be influenced. For example, the number of online bills produced was the most sensitive. However, the results are reversed under commonly occurring customer use situations. The study demonstrates the positive and negative impacts from the digitalisation of businesses. It suggests remedies based on the main drivers identified under company, contractor and customer control that led to energy consumption and environmental and land use impacts.

Impact of potato cultivation and cattle farming on physicochemical parameters and enzymatic activities of Neotropical high Andean Páramo ecosystem soils

The Andean Páramos are high mountain ecosystems whose soils are essential for the management of South American water resources, but research on anthropic impacts to these soils is currently minimal and insufficient. The objective of this study was to evaluate the impacts of potato (Solanum tuberosum) cultivation and livestock on the physicochemical parameters and enzymatic activities that determine the soil quality of the Neotropical high Andean Páramo ecosystem in the Nevados National Natural Park (Nevados NNP) in Colombia. It was hypothesised that sites with potato crops and livestock farming would exhibit significant changes in soil physicochemical parameters and enzymatic activities compared with Páramo sites that have been conserved without agriculture. Samples were collected from soils under potato cultivation, livestock and Páramo (subject to the lowest degree of human intervention possible), on three farms in the El Bosque District at three different altitudes (Buenos Aires, El Edén and La Secreta) during two seasons (dry and rainy). The results showed that none of the physical parameters under study presented statistically significant differences due to the type of use (livestock, potato crop or Páramo), season of sampling (dry or rainy season) or altitude (different farms). The chemical parameters that statistically significantly differed due to land use were organic carbon, cation exchange capacity, calcium, potassium, and ammonium and those that showed statistically significant differences associated with the sampling timing were organic carbon, nitrogen, cation exchange capacity, total carbon, C/N and nitrate. Additionally, there were differences in organic carbon due to the altitude of the farms. With respect to enzymatic activities, those of β-glucosidase, phosphodiesterase and urease significantly decreased in soils under potato cultivation and livestock relative to those of Páramo, but those of acid phosphatase and protease increased significantly under potato cropping and livestock. The activities of β-glucosidase, acid phosphatase, alkaline phosphatase, phosphodiesterase and protease were higher during the dry season than the rainy season, and the activities of β-glucosidase, acid phosphatase and urease decreased statistically in the lower-altitude farm (La Secreta). These decreases in enzymatic activities are attributable to changes in the organic carbon of the soil. This study provides a novel insight on the relationships between land use and the physicochemical parameters and enzymatic activities of Páramo soils (which have been minimally studied to date) at different altitudes and during different seasons. The results suggest that changes in agricultural practices should be implemented to maintain the organic carbon of soil and, therefore, its enzymatic activities.

Accounting for land use in life cycle assessment: The value of NPP as a proxy indicator to assess land use impacts on ecosystems

Terrestrial land and its resources are finite, though, for economic and socio-cultural needs of humans, these natural resources are further exploited. It highlights the need to quantify the impact humans possibly have on the environment due to occupation and transformation of land. As a starting point of this paper (1(st) objective), the land use activities, which may be mainly socio-culturally or economically oriented, are identified in addition to the natural land-based processes and stocks and funds that can be altered due to land use. To quantify the possible impact anthropogenic land use can have on the natural environment, linked to a certain product or service, life cycle assessment (LCA) is a tool commonly used. During the last decades, many indicators are developed within the LCA framework in an attempt to evaluate certain environmental impacts of land use. A second objective of this study is to briefly review these indicators and to categorize them according to whether they assess a change in the asset of natural resources for production and consumption or a disturbance of certain ecosystem processes, i.e. ecosystem health. Based on these findings, two enhanced proxy indicators are proposed (3(rd) objective). Both indicators use net primary production (NPP) loss (potential NPP in the absence of humans minus remaining NPP after land use) as a relevant proxy to primarily assess the impact of land use on ecosystem health. As there are two approaches to account for the natural and productive value of the NPP remaining after land use, namely the Human Appropriation of NPP (HANPP) and hemeroby (or naturalness) concepts, two indicators are introduced and the advantages and limitations compared to state-of-the-art NPP-based land use indicators are discussed. Exergy-based spatially differentiated characterization factors (CFs) are calculated for several types of land use (e.g., pasture land, urban land).