Natural climate solutions.The way forward

Climate change is a global challenge that threatens global ecological security and sustainable development.Find-ing ways to mitigate their impacts is paramount through engineering carbon storage,low-carbon energy tran-sition,or natural climate solutions(NCS).NCS involve a set of measures(e.g.,afforestation,land restoration,biochar reuse or sustainable land use practices).Implementing NCS increases carbon sequestration and mitigates climate change at the lowest costs and greenest ways.In addition,NCS practices can improve multiple ecosystem services(ES)such as air quality,flood and erosion regulation,pest control,water purification,wild food biomass,recreation or landscape aesthetics.However,unsustainable implementation of NCS,such as over-afforestation of dense mono-forest,can lead to tradeoffs with water supply,wildfire risk,and decreased grasslands and crop-lands.Therefore,to optimise the NCS implementation,reducing the tradeoffs associated and transforming the“expand ecosystem area”to“improve ecosystem management efficiency”is vital.Although NCS can contribute significantly to mitigating climate change,systematic climate actions must be accompanied by a transformation in the global society and investment in new technologies.This will be key to addressing global challenges such as the achievement of Sustainable Development Goals(SDGs),such as SDG 13(Climate Action),SDG 15(Life on Land),SDG 2(Zero Hunger),SDG 3(Good Health and Wellbeing),SDG 6(Clean Water and Sanitation),and SDG 14(Life Bellow Water).

AN IMPROVED MODEL FOR COMPUTING SOLUTION DYNAMICS OF NATURAL PRODUCTS WITH ^(13)C NUCLEAR MAGNETIC RELAXATION

The fully anisotropic molecular overall tumbling model with methyl conformation jumps internal rotation among three equivalent sites is proposed,the overall tumbling rotation rates and the methyl internal rotation rates of ponicidin are computed with this model from ~C relaxation parameters.

EXISTENCE OF NONTRIVIAL SOLUTION OF QUASILINEAR ELLIPTIC EIGENVALUE PROBLEM ON R^n WITH NATURAL GROWTH CONDITIONS

In this paper, we get the existence result of the nontrivial weak solution (λ, u) of the following eigenvalue problem with natural growth conditions.

Effects of leachate infiltration and desiccation cracks on hydraulic conductivity of compacted clay

Both cracks in clay liner and the complex composition of landfill leachate might have effects on the hydraulic conductivity of a compacted clay liner. In this study, the hydraulic conductivities of natural clay and bentonite-modified clay with and without desiccation cracks were measured, respectively, using three types of liquids as permeating liquid： 2 500 mg/L acetic acid solution, 0.5 mol/L CaCl2 solution, and tap water. When tap water was adopted as the permeating liquid, desiccation cracks resulted in increases in the average value of hydraulic conductivity： a 25-fold increase for the natural clay and a 5.7-fold increase for the bentonite-modified clay. It was also found out that the strong selfhealing capability of bentonite helped to reduce the adverse impact of cracks on hydraulic performance. In contrast to tap water, simulated leachates（acetic acid and CaCl2 solutions） show no adverse effect on the hydraulic conductivities of natural and bentonite-modified clays. It is concluded that desiccation cracks and bentonite have more significant effects on hydraulic performance than simulated leachates.

Biodiversity-friendly Agricultural Practices in the Indigenous Agricultural Systems in the Biodiversity Corridor of the Alto Paraná Atlantic Forest (Paraguay)

Agricultural systems result of the coevolution between social and natural systems,where biodiversity and natural resources play an important role,emerging interactions between crops and the natural environment that allow the development of ecological processes which interact with external inputs.This research aims to describe the agricultural practices developed by the Guarani Indigenous people in the agricultural systems located within the biodiversity corridor of the Upper Parana Atlantic Forest.This exploratory study is focused on multiple cases,with a qualitative approach and from data collected during 2017 and 2018 in eleven indigenous communities.The main practices developed for the management of biodiversity are polyculture,rotation,and embroideries;they also practice agroforestry and livestock-raising.The main difficulty they face is the reduction of the surrounding biodiversity,which affects the sustainability of the system.This study shows ways for nature-based solutions and ecosystem-based adaptation according to current needs for greening the economy.

Comparison between lighting performance of a virtual natural lighting solutions prototype and a real window based on computer simulation

This article discusses the measurement and simulation of a first generation prototype of Virtual Natural Lighting Solutions （VNLS）, which are systems that can artificially provide natural lighting as well as a realistic outside view, with properties comparable to those of real windows and skylights. Examples of employing Radiance as a simulation tool to predict the lighting performance of such solutions are shown, for a particular case study of a VNLS prototype displaying variations of a simplified view of overcast, clear, and partly cloudy skies. Measurement and simulation were conducted to evaluate the iUuminance distribution on workptane level. The key point of this study is to show that simulations can be used to compare an actual VNLS prototype with a hypothetical real window under the same sky scenes, which was physically not possible, since the test room was not located at the building＇s facade. It is found that the investigated prototype yields a less rapidly drop iUuminance distribution and a larger average illuminance than the corresponding real window, under the overcast （52 lx compared to 28 lx） and partly cloudy （102 lx compared to 80 lx） sky scenes. Under the clear sky scene, the real window yields a larger averase illuminance （97 lx） compared to the prototype （71 lx）, due to the influence of direct sunlight.

Physical Diffusion and Electron-transfer Dynamics of Electroactive Solutes in Polymer Electrolytes Ⅰ. Effect of the Nature of Electroactive Solutes

The diffusion coefficients(Dapp) and the heterogeneous electron-transfer rate constants(ks)for ferrocene and its seven derivatives in MPEG/LiClO4 electrolyte were determined by using steadystate voltammetry. The two parameters increase with increasing temperature, indicating Arrhenius behavior. The effects of the nature of electroactive solute molecules on Dapp, ks, and the half-wave potentials(E1/2) are discussed.