Multivariate Approach to Characterizing Soil Quality of Gabonese’s Ferralitic Soils

Assessing soil quality is essential for crop management and soil temporal changes. The present study aims to evaluate soil quality in the Ferralitic soils context countrywide. This assessment was done using multivariate soil quality indice (SQI) models, such as additive quality index (AQI), weighted quality indexes (WQIadd and WQIcom) and Nemoro quality index (NQI), applied to two approaches of indicator selection: total data set (TDS) and minimum data set (MDS). Physical and chemical soil indicators were extracted from the ORSTOM’s reports resulting from a sampling campaign in different provinces of Gabon. The TDS approach shows soil quality status according to eleven soil indicators extracted from the analysis of 1,059 samples from arable soil layer (0 - 30 cm depth). The results indicated that 87% of all provinces presented a very low soil quality (Q5) whatever the model. Among soil indicators, exchangeable K+ and Mg2+, bulk density and C/N ratio were retained in MDS, using principal component analysis (PCA). In the MDS approach, 50 to 63% of provinces had low soil quality grades with AQI, WQIadd and NQI, whereas the total was observed with WQIcom. Only 25% of provinces had medium soil quality grades with AQI and NQI models, while 12.5% (NQI) and 25% (AQI) presented high quality grades. Robust statistical analyses confirmed the accuracy and validation (0.80 r P ≤ 0.016) of AQI, WQIadd and NQI into the TDS and MDS approaches. The same sensitivity index value (1.53) was obtained with AQI and WQIadd. However, WQIadd was chosen as the best SQI model, according to its high linear regression value (R2 = 0.82) between TDS and MDS. This study has important implications in decision-making on monitoring, evaluation and sustainable management of Gabonese soils in a pedoclimatic context unfavorable to plant growth.

Do Land Characteristics Affect Farmers' Soil Fertility Management?

Soil fertility management （SFM） has important implications for sustaining agricultural development and food self-sufifciency. Better understanding the determinants of farmers’ SFM can be a great help to the adoption of effective SFM practices. Based on a dataset of 315 plots collected from a typical rice growing area of South China, this study applied statistical method and econometric models to examine the impacts of land characteristics on farmers’ SFM practices at plot scale. Main results showed that in general land characteristics affected SFM behaviors. Securer land tenure arrangements facilitated effective practices of SFM through more diversiifed and more soil-friendly cropping pattern choices. Plot size signiifcantly reduced the intensities of phosphorus and potassium fertilizer application. Given other factors, 1 ha increase in plot size might reduce 3.0 kg ha-1 P2O5 and 1.8 kg ha-1 K2O. Plots far from the homestead were paid less attention in terms of both chemical fertilizers and manure applications. Besides, plots with better quality were put more efforts on management by applying more nitrogen and manure, and by planting green manure crops. Signiifcant differences existed in SFM practices between the surveyed villages with different socio-economic conditions. The ifndings are expected to provide important references to the policy-making incentive for improving soil quality and crop productivity.

Assessment of the Physicochemical Quality of Irrigation Water and Soil for Sustainable Irrigated Rice Cultivation:Case of Irrigated Perimeter of M’Bahiakro(Central-East of Cote d’Ivoire)

This study aims to assess the physico-chemical quality of irrigation water and soil in the irrigated area of M’Bahiakro. Seasonal campaigns to measure in situ the physical parameters (pH, temperature, salinity, electrical conductivity and total dissolved solids) of the N’Zi River were carried out, followed by sampling (water and soil) for chemical analyses. The physico-chemical quality of irrigation water was assessed on the basis of four (4) parameters, namely Dry Residue (SR), Osmotic Pressure (π), Kelly Coefficient (KCR), Sodium Absorption Rate (SAR) and Wilcox Diagram. In terms of soil quality, the parameters (pH, N, P, P, K, MO, CEC and ESP) were determined. Overall, the results show a good physical-chemical quality of the irrigation water and soil. Indeed, the irrigation waters studied show good physico-chemistry and low to medium salinity depending on the seasons of the year. As for the soils, they have a clayey-silt texture, a slightly acidic pH, favourable to rice cultivation and a good organic matter content, which best maintains an active microbial life. In addition, the major elements (nitrogen, phosphorus and potassium) present in irrigation water and soils could be enough to optimize the yield of rice cultivation. These results then lead to the conclusion that the irrigation water from the N’Zi River and the soils of the irrigated perimeter of M’Bahiakro are naturally suitable for agricultural use, particularly for rice cultivation. As a result, an additional supply of fertilizer (NPK) would not necessarily be necessary during the exploitation phase of the rice area.

Prioritizing woody species for the rehabilitation of arid lands in western Iran based on soil properties and carbon sequestration

Plants are an important component in many natural ecosystems. They influence soil properties, especially in arid ecosystems. The selection of plant species based on their adaptations to site conditions is essential for rehabilitation of degraded sites and other construction sites such as check-dams. Other factors to be considered in species selection include their effects on soil properties and their abilities to meet other management objectives. The purpose of this study was to assess the effects of native(Populus euphratica Oliv. and Tamarix ramosissima Ledeb.) and introduced(Eucalyptus camaldulensis Dehnh. and Prosopis juliflora(Swartz) DC.) woody species on soil properties and carbon sequestration(CS) in an arid region of Iran. Soil sampling was collected at three soil depths(0–10, 10–20 and 20–30 cm) at the sites located under each woody species canopy and in an open area in 2017. Soil physical-chemical property was analyzed in the laboratory. The presence of a woody species changed soil characteristics and soil CS, compared with the open area. For example, the presence of a woody species caused a decrease in soil bulk density, of which the lowest value was observed under E. camaldulensis(1.38 g/cm^3) compared with the open area(1.59 g/cm^3). Also, all woody species significantly increased the contents of soil organic matter and total nitrogen, and introduced species had more significant effect than native species. The results showed that CS significantly increased under the canopy of all woody species in a decreasing order of P. euphratica(9.08 t/hm^2)>E. camaldulensis(8.37 t/hm^2)>P. juliflora(5.20 t/hm^2)>T. ramosissima(2.93 t/hm^2)>open area(1.33 t/hm^2), thus demonstrating the positive effect of a woody species on CS. Although the plantation of non-native species had some positive effects on soil properties, we recommend increasing species diversity in plantations of native and introduced woody species to provide more diversity for the increased ecosystem services, resilience, health and long-term productivity.

Relationship between Selected Soil Physico-Chemical Characteristics and Mycorrhizal Status under <i>Triumfetta cordifolia</i>in the Cameroon Western Highlands

There is limited information on the pedological requirements of Triumfetta cordifolia. A starting point for establishing such information requires knowledge on the growing environment of the species. The aim of this study was to assess the physicochemical properties and mycorrhizal status in the rhizosphere of Triumeffa cordifolia. Soil and root samples from the rhizosphere of T. cordifolia were collected from three localities (Santchou, Bandjoun, and Balatchi) in the West Region of Cameroon. The results show that the soils are dominated by a loamy texture and have a mean porosity > 50%. Mean bulk density ranges from 0.91 ± 0.02 to 1.26 ± 0.04 g⋅cm−3. The sum of exchangeable cations ranges from medium (6.45 ± 1.02) to high (11.21 ± 1.35) and are evident of the satisfactory soil organic matter (OM) content in the various localities (5.90% ± 0.42% to 10.65% ± 0.73%). Total nitrogen (TN) content of the soils ranged from low (0.10%) to very high (0.41%). Biological activity is low due to very poor OM quality (mean C/N > 20). The average available phosphorus status ranged from medium (18.32 ± 3.91 ppm) to very high (69.39 ± 26.09 ppm). The Cationic Exchange Capacity (CEC) was moderate (19.28 - 29.28 cmol⋅kg−1) and was mainly contributed by soil organic matter. Base saturation ranged from low (28.0%) to medium (48.83%). Assessment of endomycorrhizal colonization showed that the intensity (I), frequency (Fr) and specific density of spores (Ds) were not significantly different among sites. A high level of available P in the Santchou soils appears to be the major cause for the lowest values of Fr, I, and Ds observed. These results reaffirm the link between soil physicochemical properties and endomycorrhizal infection in T. cordifolia. Site characteristics and soil OM quality are factors to be considered in promoting the establishment of mycorrhizal symbiosis for profitable and sustainable cultivation of T. cordifolia.

Changes in Soil Carbon Stocks under Integrated Crop-Livestock-Forest System in the Brazilian Amazon Region

Several studies indicate that the use of integrated production systems, such as integrated crop-livestock-forest systems (ICLF), improves the quality of the soil and consequently the sequestration of organic carbon in the soil. In this way, this work aims to evaluate the carbon stocks in soil under different management systems in the Cerrado/Amazonia transition zone, namely: ICLF, no-tillage, pasture and eucalyptus plantation. For this, two soil samplings were done in 2011 and 2014, in the 0 - 5, 5 - 10 and 10 - 30 cm layers. Soil carbon and nitrogen stocks were analyzed. ICLF system was the treatment that obtained the highest percentage of carbon gain (7.8%) after three years of establishment which represents to an increase of 5.5 Mg·ha-1. Management systems, such as ICLF, with minimal soil disturbance combined with crop rotations that contribute to the quantity and quality of residues input, increase soil organic matter content. Carbon stock data show the potential of ICLF systems to increase soil carbon stocks.

Towards defining soil quality of Mediterranean calcareous agricultural soils:Reference values and potential core indicator set

To avoid soil degradation,adapt to climate change and comply with the Sustainable Development goals 2030(UN General Assembly),establishing the quality/fertility of the agricultural soils of the Mediterranean region and evaluate how these evolve with time is mandatory.This enables adequate management practices to be implemented.The Mediterranean calcareous region has received little attention in this sense,in spite its soil particularities.So,24 different representative calcareous agricultural soils of the Mediterranean region,including the main management strategies of agricultural soils(rainfed and irrigated),were sampled from the island of Mallorca;and their physical,chemical and biological properties determined.The values obtained for most of the soil characteristics allowed to establish an initial approach to the reference values for the type of calcareous agricultural soils considered,and to clearly distinguish the effect of rainfed or irrigation management practices on soils properties and dynamics.Some enzyme activities were not stimulated by the irrigation conditions assayed or they were only in dry conditions,suggesting optimum enzyme activities could be obtained when alternating dry and humid soil conditions.Soil organic carbon,calcium carbonate and active lime revealed of significant importance in the collection of soils.Finally,the results obtained clearly indicate the heterogeneity of the region and its implications on the different soil characteristics.Therefore,this study could serve as a starting point to adequately establish the quality(fertility)for Mediterranean calcareous agricultural soils and their reference values by conducting further research in this region and including more type of soils.

Paving the way toward soil safety and health:current status,challenges,and potential solutions

Soil is a non-renewable resource,providing a majority of the world’s food and fiber while serving as a vital carbon reservoir.However,the health of soil faces global threats from human activities,particularly widespread contamination by industrial chemicals.Existing physical,chemical,and biological remediation approaches encounter challenges in preserving soil structure and function throughout the remediation process,as well as addressing the complexities of soil contamination on a regional scale.Viable solutions encompass monitoring and simulating soil processes,with a focus on utilizing big data to bridge micro-scale and macro-scale processes.Additionally,reducing pollutant emissions to soil is paramount due to the significant challenges associated with removing contaminants once they have entered the soil,coupled with the high economic costs of remediation.Further,it is imperative to implement advanced remediation technologies,such as monitored natural attenuation,and embrace holistic soil management approaches that involve regulatory frameworks,soil health indicators,and soil safety monitoring platforms.Safeguarding the enduring health and resilience of soils necessitates a blend of interdisciplinary research,technological innovation,and collaborative initiatives.

Interactions of Water Management and Nitrogen Fertilizer on Nitrogen Absorption and Utilization in Rice

The interactions of water management and nitrogen fertilizer on nitrogen absorption and utilization were studied in rice with Wuxiangjing9 (japonica). The results showed that the nitrogen uptake and remaining in straw increased and the percentage of nitrogen translocation (PNT) from vegetative organs, nitrogen dry matter production efficiency (NDMPE) and nitrogen grain production efficiency (NGPE) decreased with nitrogen increasing. The nitrogen uptake and NGPE decreased when severe water stressed. However, rice not only decreased the nitrogen uptake but also increased the PNT from vegetative organs, NDMPE and NGPE when mild water stressed. There were obvious interactions between nitrogen fertilizer and water management, such as with water stress increasing the effect of nitrogen on increasing nitrogen uptake was reduced and that on decreasing NDMPE was intensified.

Possibilities of using silicate rock powder:An overview

This study evaluates the on use of crushed rocks(remineralizers)to increase soil fertility levels and which contributed to increase agricultural productivity,recovery of degraded areas,decontamination of water,and carbon sequestration.The use of these geological materials is part of the assumptions of rock technology and,indirectly,facilitates the achievement of sustainable development goals related to soil management,climate change,and the preservation of water resources.Research over the past 50 years on silicate rocks focused on soil fertility management and agricultural productivity.More recently,the combined use with microorganisms and organic correctives have shown positive results to mitigate soil degradation;to expand carbon sequestration and storage;and to contribute to the adsorption of contaminants from water and soil.In this article we show results obtained in several countries and we show that this technology can contribute to the sustainability of agriculture,as well as to reverse global warming.Although mineral nutrients are released more slowly from these types of inputs,they remain in the soil for a longer time,stimulating the soil biota.In addition,they are a technology to soluble synthetic fertilizers replace,since the few nutrients derived from such inputs not consumed by plants are lost by leaching,contaminating groundwater and water resources.In addition,conventional methods rely heavily on chemical pesticides which cause damage to soil’s microfauna(responsible for the decomposition of organic matter and nutrient cycling)and the loss of organic carbon(in the form of dioxide),which is quickly dispersed in the atmosphere.Silicate rock powders are applied in natura,have long-lasting residual effects and reduce greenhouse gas emissions.

Profitability and Farmer Acceptability of Selected Climate Smart Technologies and Practices for Maize-Beans Production in Drought-Prone Areas, Uganda

Climate change is increasingly affecting farm-level decisions on when to plant and which climate smart agriculture (CSA) options to use. This study was conducted to determine the profitability and farmer acceptability of different CSA options for maize-bean production in drought-prone areas of Uganda. It was conducted on-farm in Rakai and Nakasongola districts during 2020 and 2021. Variables included: planting date (early vs late);varieties (common beans: NABE 4 and NAROBEAN 2, and maize: Longe 5 and Bazooka);intercropping versus pure stand;and fertiliser use (manure, Diammonium phosphate (DAP) or combination). The experimental design was split-split plot, replicated six times. Over two years, early planting caused 16% and up to 46% higher yields of maize and beans, respectively, than late planting, resulting in 14% - 28% and 18% - 43% higher Benefit/Cost (B/C) ratio for maize and beans, respectively. Intercropping reduced maize and beans yield by 16% - 25% and 52% - 57%, respectively. The B/C was highest for sole maize;intercropping was more profitable than sole beans. Fertilizer (DAP) was most profitable when Bazooka was early-planted as sole crop followed by intercrop. For late planted-crop, manure was better. These practices were more beneficial when applied simultaneously for both crops excluding bean variety. Farmers’ lessons stressed the importance of early planting and fertilizer use;however, majority indicated they were to adopt more than two of the practices tested.

Biochar increases soil microbial biomass with changes in extra-and intracellular enzyme activities:a global meta-analysis

Biochar application to soil has been proposed as a potential management strategy to enhance soil carbon(C)sequestration,reduce greenhouse gas emission,improve soil quality,and increase crop productivity.The effects of biochar on soil microbial and enzyme activities are integrally linked to the potential of biochar in achieving these benefits.We conducted a global meta-analysis to assess the effects of biochar on soil microbial biomass C and nitrogen(N)and the activities of 12 enzymes,and identify key factors affecting those soil microbial properties using 964 data points from 72 papers.We found that biochar effects on enzyme activities vary widely with soil type,biochar property and the type of enzyme studied.Biochar significantly increased microbial biomass C(MBC)and urease,alkaline phosphatase and dehydrogenase activities by 21.7%,23.1%,25.4%and 19.8%,respectively,with no significant negative effects on any of the enzymes analyzed in this study.Biochar application was more effective in increasing MBC and enzyme activities in soils with low pH(<6.5),TC(<20 g kg^(−1)),TN(<2 g kg^(−1)),and a fine texture(including clay,clay loam and silt clay).Biochars produced at pyrolysis temperature of 350-550℃ with a high pH(>10)and low C/N ratio(<50)increased MBC and urease and dehydrogenase activities.Biochar increased MBC and N-acquisition enzyme activities in the field but not in lab incubation experiments.Urease was increased in short-term studies(within 100 days of biochar application)while alkaline phosphatase was increased in long-term studies that span more than 1 year.The increase in MBC and activities of some soil enzymes in response to biochar application with no negative effects on any hydrolytic and oxidative enzymes illustrate its potential to enhance soil quality particularly in the degraded soils with low nutrient availability and fertility due to limited soil microbial and enzymatic activities.This study also shows that biochars can be designed to achieve specific properties for enhancing microbial and enzymatic activities for specific soils.

New approaches for evaluation of soil health, sensitivity and resistance to degradation

Assessment of soil health requires complexevaluation of properties and functions responsible for abroad range of ecosystem services. Numerous soil qualityindices (SQI) have been suggested for the evaluation ofspecific groups of soil functions, but comparison of variousSQI is impossible because they are based on a combinationof specific soil properties. To avoid this problem, wesuggest an SQI-area approach based on the comparison ofthe areas on a radar diagram of a combination of chemical,biological and physical properties. The new approach isindependent of the SQI principle and allows rapid andsimple comparison of parameter groups and soils. Anotherapproach analyzing the resistance and sensitivity ofproperties to degradation is suggested for a detailedevaluation of soil health. The resistance and sensitivityof soil properties are determined through comparison withthe decrease of soil organic carbon (SOC) as a universalparameter responsible for many functions. The SQI-areaand resistance/sensitivity approaches were tested based on quences after the ab and on ment of agricultural soils. Both the SQI-area and the resistance/sensitivity approaches areuseful for basic and applied research, and for decisionmakersto evaluate land-use practices and measure thedegree of soil degradation.

Evaluation of soil erosion risk and identification of soil cover and management factor (C) for RUSLE in European vineyards with different soil management

Vineyards show some of the largest erosion rates reported in agricultural areas in Europe.Reported rates vary considerably under the same land use,since erosion processes are highly affected by climate,soil,topography and by the adopted soil management practices.Literature also shows differences in the effect of same conservation practices on reducing soil erosion from conventional,bare soil based,management.The Revised Universal Soil Loss Equation(RUSLE)is commonly adopted to estimate rates of water erosion on cropland under different forms of land use and management,but it requires proper value of soil cover and management(C)factors in order to obtain a reliable evaluation of local soil erosion rates.In this study the ORUSCAL(Orchard RUSle CALibration)is used to identify the best calibration strategy against long-term experimental data.Afterwards,ORUSCAL is used in order to apply the RUSLE technology from farm based information across different European wine-growing regions.The results suggest that the best strategy for calibration should incorporate the soil moisture sub-factor(Sm)to provide better soil loss predictions.The C factor,whose average values ranged from 0.012 to 0.597.presented a large spatial variability due to coupling with local climate and specific local management.The comparison across the five wine-growing regions indicates that for the soil protection management,permanent cover crop is the best measure for accomplishing sustainable erosion rates across the studied areas.Alternate and temporary cover crops,that are used in areas of limited water resources to prevent competition with vines,failed to achieve sustainable erosion rates,that still need to be addressed.This raises the need for a careful use of C values developed under different environmental conditions.

Mapping soil nutrients via different covariates combinations:theory and an example from Morocco

Background:Mapping of soil nutrients using different covariates was carried out in northern Morocco.This study was undertaken in response to the region’s urgent requirement for an updated soil map.It aimed to test various covariates combinations for predicting the variability in soil properties using ordinary kriging and kriging with external drift.Methods:A total of 1819 soil samples were collected at a depth of 0–40 cm using the 1-km grid sampling method.Samples were screened for their pH,soil organic matter(SOM),potassium(K_(2)O),and phosphorus(P_(2)O_(5))using standard laboratory protocols.Terrain attributes(T)computed using a 30-m resolution digital elevation model,bioclimatic data(C),and vegetation indices(V)were used as covariates in the study.Each targeted soil property was modeled using covariates separately and then combined(e.g.,pH~T,pH~C,pH~V,and pH~T+C+V).k=tenfold cross-validation was applied to examine the performance of each employed model.The statistical parameter RMSE was used to determine the accuracy of different models.Results:The pH of the area is slightly above the neutral level with a corresponding 7.82%of SOM,290.34 ppm of K_(2)O,and 100.86 ppm of P_(2)O_(5).This was used for all the selected targeted soil properties.As a result,the studied soil properties showed a linear relationship with the selected covariates.pH,SOM,and K 2O presented a moderate spatial autocorrelation,while P2O5 revealed a strong autocorrelation.The cross-validation result revealed that soil pH(RMSE=0.281)and SOM(RMSE=9.505%)were best predicted by climatic variables.P_(2)O_(5)(RMSE=106.511 ppm)produced the best maps with climate,while K_(2)O(RMSE=209.764 ppm)yielded the best map with terrain attributes.Conclusions:The findings suggest that a combination of too many environmental covariates might not provide the actual variability of a targeted soil property.This demonstrates that specific covariates with close relationships with certain soil properties might perform better than the compilation of different environmental covariates,introducing errors due to randomness.In brief,the approach of the present study is new and can be inspiring to decision-makers in the region and other world areas as well.

Soil conservation and sustainable development goals(SDGs)achievement in Europe and central Asia:Which role for the European soil partnership?

Voluntary soil protection measures are not sufficient to achieve sustainable soil management at a global scale.Additionally,binding soil protection legislation at national and international levels has also proved to be insufficient for the effective protection of this almost non-renewable natural resource.The European Soil Partnership(ESP)and its sub-regional partnerships(Eurasian Sub-Regional Soil Partnership,Alpine Soil Partnership)were established in the context of FAO's Global Soil Partnership(GSP)with the mission to facilitate and contribute to the exchange of knowledge and technologies related to soils,to develop dialogue and to raise awareness for the need to establish a binding global agreement for sustainable soil management The ESP has taken a role of an umbrella network covering countries in Europe and Central Asia.It aims to improve the dialogue in the whole region and has encouraged establishing goals that would promote sustainable soil management taking into account various national and local approaches and priorities,as well as cultural specificities.The ESP first regional implementation plan for the 2017—2020 period was adopted and implemented along the five GSP pillars of action.Building on the experience of the last four years,this study demonstrates that establishing sub-regional and national partnerships is an additional step in a concrete sustainable soil management implementation process.It also suggests that a complementary approach between legal instruments and voluntary initiatives linked to the development of efficient communication and strong commitment is the key to success.

The transformation of agriculture in Brazil through development and adoption of Zero Tillage Conservation Agriculture

The soil conservation movement in Brazil has been a major driving force in the continuing search for agricultural farming systems that are more sustainable than what we have today,particularly in tropical and subtropical areas.The development and adoption of Zero Tillage Conservation Agriculture(ZT/CA)was the key to the success of this movement,generating agricultural,environmental,and societal benefits.Adoption of the ZT/CA philosophy and technologies is currently practiced on more than 50%of the annual crop area.This is due to the work and innovations of pioneering farmers,agronomists,researchers,and consultants that were and are involved in these efforts.This extensive adoption of ZT/CA occurred after many unsuccessful efforts to mitigate against the devastating effects of soil erosion that were threatening the entire agricultural industry in Brazil.Technicians and farmers realized that erosion control required continual cover of the soil to guard against the torrential rain storms common to these regions.This triggered the efforts of soil conservation pioneers at different points in time and regions of Brazil.In southern Brazil,Herbert Bartz,watched his topsoil eroding away in torrents of runoff.This set him thinking and searching for alternatives,resulting in his adoption of ZT/CA farming in 1972.Ten years later in Brazil’s centre-western savannah(Cerrado biome),farmers,researchers,crop consultants and agro-industry initiated efforts to expand cultivation into the very difficult production region of the Cerrados.This was successfully achieved through the pioneering work of agronomist John Landers,bringing experience from the ZT/CA farmer association networks in the south.These were the turning points in the sustainable development of annual crop farming in Brazil.Today,society recognizes the role of these pioneers as key to achieving social,economic and environmental sustainability.ZT/CA reversed the historically accelerating degradation of soil organic matter and soil structure by abandoning conventional tillage,thus improving soil physical and chemical characteristics.This was achieved by promoting cover cropping and permanent soil cover with crop residues,crop rotations,and complementary,environmentally suitable soil management technologies.

HARNESSING ECOLOGICAL PRINCIPLES AND PHYSIOLOGIC MECHANISMS IN DIVERSIFYING AGRICULTURAL SYSTEMS FOR SUSTAINABILITY:EXPERIENCE FROM STUDIES DEPLOYING NATUR-EBASED SOLUTIONS IN SCOTLAND

To achieve the triple challenge of food security,reversing biodiversity declines plus mitigating and adapting to climate change,there is a drive to embed ecological principles into agricultural,value-chain practices and decisionmaking.By diversifying cropping systems at several scales there is potential to decrease reliance on inputs,provide resilience to abiotic and biotic stress,enhance plant,microbe and animal biodiversity,and mitigate against climate change.In this review we highlight the research performed in Scotland over the past 5 years into the impact of the use of ecological principles in agriculture on sustainability,resilience and provision of ecosystem functions.We demonstrate that diversification of the system can enhance ecosystem functions.Soil and plant management interventions,including nature-based solutions,can also enhance soil quality and utilization of legacy nutrients.Additionally,this is facilitated by greater reliance on soil biological processes and trophic interactions.We highlight the example of intercropping with legumes to deliver sustainability through ecological principles and use legumes as an exemplar of the innovation.We conclude that there are many effective interventions that can be made to deliver resilient,sustainable,and diverse agroecosystems for crop and food production,and these may be applicable in any agroecosystem.

New approach for obtaining the C-factor of RUSLE considering the seasonal effect of rainfalls on vegetation cover

We present a new approach for calculating the C-factor of RUSLE considering the effect of low-reflectance vegetation cover areas on the reduction of the effects on erosion caused by rainfall seasonality.For this,we propose the coefficients Cr2(rescaled 2)and C-PC(Precipitation Correction),which represent the Cfactor,and an adaptation in NDVI calculation,according to the seasonality of precipitation(NDVI-PC).The Cr2 factor is used when there is no seasonal effect of rainfall on vegetation,while the C-PC factor is calculated for localities under the influence of seasonality,from NDVI-PC.The proposed approaches were tested using different satellites images in the Palmares-Ribeir~ao do Saco watershed,Rio de Janeiro,Brazil.The values of Cr2 and C-PC factors were compared to the Cr factor(rescaled)and to mean values from the literature for different land covers.Our results indicated that the Cr2 factor represents an improvement in accuracy in relation to Cr by considering specific values of the studied area to normalize the data without generalizations.Furthermore,the C-PC factor is able to simulate the effect of seasonality,providing more realistics values of soil loss by the RUSLE as a function of the proportion of area affected by the rainfall seasonality obtained from NDVI-PC.We conclude that both Cr2 and C-PC factors generate values similar of the C-factor observed in the literature,and therefore are able to provide better soil loss estimation than that using the Cr factor.