Soil Fertility Indicators Research Articles

Influence of Microalgae Biomasses Retrieved from Phycoremediation of Wastewaters on Yield of Lettuce, Soil Health, and Nitrogen Environmental Fate

The main purpose of this study was to investigate the effects of three microalgae strains, Chlorella vulgaris, Scenedesmus quadricauda, and Klebsormidium sp. K39, on the enhancement of lettuce yield and soil fertility and in mitigation of nitrogen losses in groundwater, focusing on some aspects of the complex soil-plant system. The experimental trials were carried in pots, and involved the application of microalgae cells at two different concentrations (50 and 500 mg kg− 1 of soil), alone or in combination with standard mineral fertilization. The yield, main morpho-biometric parameters, and protein content of lettuce seedlings, as well as the activities of key enzymes involved in the nitrogen pathway (nitrate reductase, glutamine synthase, and glutamate synthetase) at both root and shoot levels, were monitored and the results were compared to not-inoculated control plants. The nitrate leached due to over irrigation was also evaluated. Furthermore, even the effects of microalgae biostimulants on soil biochemical activity were analysed by monitoring fluorescein diacetate hydrolysis, dehydrogenase, acid and alkaline phosphomonoesterase, and urease activities. All treatments significantly improved lettuce growth, especially when combined with mineral fertilization, providing comparable levels to the control plants treated only with microalgae cells. Furthermore, microalgae treatments positively influenced soil biological activities, as evidenced by increased of the potential biochemical index of soil fertility (Mw). In conclusion, microalgae soil treatments may be considered as a viable strategy to assist growers in reducing the use of mineral fertilizers, with a view to improve plant growth as well as soil biological activity.

The effects of thinning on carbon and nutrient fluxes input into forest floor via litterfall in black pine afforestation sites.

As a component of the biogeochemical cycle, litterfall contributes carbon and nutrients to forest ecosystems by transferring organic material to mineral soil. Litterfall therefore serves as an important indicator for soil fertility and ecosystem health. This study aimed to determine the impact of different levels of thinning (light, moderate, and heavy) on litterfall quantity (needles, branches, bark, cones, and miscellaneous parts) and on the amount of carbon and nutrients entering the ecosystem in black pine afforestation areas. Three levels of low thinning, namely light, moderate, and heavy thinning (15%, 25%, and 35% of breast height area, respectively), were applied as treatments. Additionally, a control plot was included in the experiment. Litterfall samples were collected four times per year (once per season) from 12 treatment plots for three years. In the laboratory, dry weight measurements and analyses of carbon and macro-micro nutrient elements (N, P, K, Ca, Mg, S, Na, Fe, Cu, Zn, and Mn) were performed on litterfall samples taken from the field. Differences between treatments in terms of litterfall and the amount of carbon and nutrient elements entering the ecosystem were evaluated through variance analysis and the Duncan test. According to the findings, the quantity of litterfall input into the forest floor was highest in the control treatment, at 6,543kgha-1year-1 and lowest in the heavy treatment, at 4,378kgha-1year-1, showing a significant variation in litterfall quantity. The input of C to the soil ranged between 2,233kgha-1year-1 and 3,347kgha-1year-1 depending on thinning treatment. Although thinning treatment reduced C input to the soil, there was no significant difference among treatments. This also applied to nutrient elements such as N, P, K, Mg, and S. Needles constituted the majority of litterfall components (60%) and had the highest C density among all components, at 51.2%. The weighted carbon ratio for litterfall was calculated at 50.8%. Considering carbon-focused planning, performing moderate thinning interventions in the study area or similar pine-afforested areas may be a suitable option for maintaining the sustainability and health of the forest.

Soil nutrient prediction for paddy cultivation via soil fertility and pH trained hybrid architecture: Recommendations based on nutrient deficiency

Soil testing can assist in determining how much fertilizer is necessary, as it depends on the fertility and crop of the soil. Through soil fertility and pH-trained hybrid architecture, a new soil nutrient prediction model for paddy agriculture is proposed in this work. First, data acquisition takes place, which is the act of gathering soil data, and it is subsequently preprocessed using the Improved Normalization method. A soil information dataset is employed in this work to help with this. Subsequently, the preprocessed data undergoes data augmentation; the correlation method facilitates an enhanced data augmentation procedure. In this case, the data used for the correlation approach is min-max normalization data. The augmented data is used to extract soil properties such as pH level and soil fertility index. Additionally, a hybrid classifier strategy that combines RNN and Modified LSTM is suggested for nutrient prediction. Lastly, this article suggested some fertilizers for nutritional insufficiency based on the projection. The hybrid prediction classifiers that have been suggested perform better in experiments than the classic classifier models, which include LSTM, RNN, SVM, Bi-GRU, and DNN, in terms of sensitivity, accuracy, FPR, MCC, precision, and efficiency in predicting nutrients. Even though the CNN (0.075), Bi-GRU (0.080), LSTM (0.087), DBN (0.078), Enhanced-1DCNN DLM (0.080), RNN (0.085), and RFA (0.052) obtained maximal FPR ratings, the FPR of the Modified LSTM+RNN scheme is 0.052.

Evaluation of the trade-off between water use efficiency and nutrient use efficiency in two semiarid coniferous tree species growing on an organic amended metalliferous mine tailing substrate

We evaluated the ecophysiological responses of two semiarid coniferous tree species, Pinus halepensis and Tetraclinis articulata, growing on a nutrient-poor metalliferous mine tailings substrate to organic amendments (biochar and/or organic municipal waste). The trees were grown in mesocosms under irrigated conditions for 20 months. Then, a comprehensive characterization of soil and plant parameters (including stable isotopes) was carried out. Treatments containing municipal waste showed better soil fertility indicators (approximately 2-fold higher organic carbon and total nitrogen concentrations) and higher plant biomass (up to 5-fold higher) than unamended and only biochar treatments. Trees in most of the treatments exhibited leaf N/P ratios <14 indicating severe N limitation of plant growth. Metal uptake was below phytotoxic levels across all the treatments. Leaf δ13C values correlated positively with δ18O across treatments for both species indicating increasing water use efficiency with tighter stomatal regulation of water flux, and with T. articulata exhibiting tighter stomatal control (higher δ18O values) than P. halepensis. Trees in treatments containing only biochar did not differ in ecophysiological performance from those in the unamended treatments. In contrast, leaf stable isotopes revealed sharply increased of time-integrated photosynthetic activity (favoured by higher leaf N concentrations) combined with lower time-integrated stomatal conductance in the treatments containing municipal waste, indicating greatly enhanced water use efficiency in better nourished plants. Trade-offs between water use efficiency and nutrient (N and P) use efficiency were evident across treatments, with higher leaf nutrient concentrations associated with higher water use efficiency, at the cost of a lower nutrient use efficiency. These trade-offs were not impaired by the high metal concentrations of the tailings substrate, indicating that ecophysiological adjustments in response to changes in plant nutrient status promoted by the addition of organic amendments are critical for the adaptability of native tree species employed in the phytostabilisation of mine tailings.

Восстановление плодородия малопродуктивных дерново-подзолистых почв, вновь вводимых в сельскохозяйственный оборот

The purpose of research is to develop agro-reclamation measures to restore the fertility of low-productive sod-podzolic sandy loam soils for the conditions of the southern part of the Non-Chernozem Zone of Russia. Objectives: to conduct a comparative assessment of the impact of granular fertilizer based on turkey droppings and a liquid-phase biological product (LPBP) on increasing soil fertility, phenological characteristics of plants, crop yields and their quality. Six variants of the field experiment were developed: control variant (without fertilizers); granular fertilizer based on turkey droppings at a dose of 15 t/ha; granular fertilizer based on turkey manure at a dose of 15 t/ha together with pre-sowing seed treatment with 1 % LPBP; pre-sowing seed treatment with 1 % LPBP; granular fertilizer based on turkey droppings at a dose of 30 t/ha. The application of organic ameliorant and pre-sowing treatment of seeds with a biological pre¬paration help to improve the agrochemical parameters of the soil, and, as a result, a higher yield of perennial grasses. The best option is option G30, where the yield was 48.3 t/ha of green mass of grass in total for 2 cuttings, which is 33.8 % more than the control option. In the G15 and G15 LPBP options, the harvest was practically not inferior and exceeded the control option by 30.5 and 24.4 %, respectively, soil fertility indicators improved: soil acidity decreased to 4.8–5.0 (pHsol) and 5.4–5.6 (pHwod), an increase in organic matter by 33.9 %, the content of mobile phosphorus and mobile potassium, and the concentration of total nitrogen increased significantly.

The Progress/Status of Ecological Assessment on the Intensive Land Use in Selenge and Darkhan-Uul Province, Mongolia

Abstract. The study area, it includes Darkhan-Uul and Selenge provinces of Mongolia, is included in the most favourable natural-geographical areas, and the migration of people with livestock from the peripheral areas has led to an increase in the population, as well as a sharp increase in the number of grazing animals, resulting in the effects of natural and human activities. give an evaluation, develop the basis for the proper use of the land in the future. In Mongolia, the methods and principles of land evaluation differ depending on the general classification and purpose of land, so considering these characteristics, land evaluation is carried out by (1) the Department of Agriculture, (2) the Department of Urban Development, Industry and Mines, (3) the Department of Roads and Networks, (4) it is divided into types of land with forest reserves (Tserenbaljir, B. Naranchimeg, 2004). In the "instructions for land evaluation" issued by the United Nations Food and Agriculture Organization (FAO) in 1976, in the assessment of land quality, in addition to the main indicators of soil fertility and moisture, climate, land cover and use, chemical pollutions such as an alkaline acidity. In the ecological assessment study, data on land use, soil, vegetation, climate, natural conditions, resources, socio-economic, satellite and field studies were collected in numerical and tabular form. The Ecological assessment in intensive land use is divided into qualitative and quantitative assessment. The Qualitative assessment predicts ecological properties. The Quantitative methods use multi-species numerical methods to record ecological elements and calculate the overall percentage of ecological characteristics.

Response of soil microorganisms to soil fertility in the process of vegetation rehabilitation of degraded Pinus massoniana forest

AbstractThe rehabilitation of diverse and three‐dimensional forest vegetation patterns is crucial for preventing forest degradation and improving soil fertility. However, the relationship between soil microbial community and soil fertility was not clear. To accurately assess the capability of vegetation restoration measures on the real impact on degraded soil ecosystems. We selected three vegetation rehabilitation models of degraded Pinus massoniana forests in typical soil erosion areas in China as the research objects, with untreated bare land as the control. All three vegetation construction patterns increased the abundance and diversity of soil bacteria and fungi, thereby enhancing the stability of the soil ecosystem. Additionally, the vegetation rehabilitation models also altered the community structure of soil bacteria and fungi in the degraded P. massoniana forests. The pH and soil fertility index (IFI) were the main factors leading to variations in the community structure of the soil bacteria and fungi. Among them, the grass‐planting model showed a significantly greater improvement in the soil fertility of degraded P. massoniana forests than the shrub‐planting and arbor‐planting models. Furthermore, Ascomycota, Basidiomycota, and Glomeromycota exhibited the most significant response to IFI, indicating their potential as indicator microorganisms for soil fertility changes. The improvement in soil fertility in degraded P. massoniana forests was influenced primarily by the increase in urease activity (S‐UE) according to the vegetation rehabilitation models (84.20%, p = 0.000). In conclusion, the grass‐planting system effectively improved the soil ecosystem quality of degraded P. massoniana forests in southern erosion‐prone areas of China and was suitable for further application.

Microbial communities overwhelm environmental controls in explaining nitrous oxide emission in acidic soils

Intensively fertilized acidic soils are global hotspots of nitrous oxide (N2O) emissions, contributing to net agronomic greenhouse gas outcomes. Identifying the key drivers of soil N2O emissions is hampered by the synergistic or antagonistic effects of multiple factors. Within a framework based on the predominant role of microbial communities producing N2O, the N2O emissions are affected either by proximal regulators: temporary soil property fluctuations affect N2O production transcriptionally, or by distal regulators: persistent genetic rearrangements in local microbial communities. The proximal regulators, individually or together, may spontaneously impact distal regulators. Here, we use acidic soils from tea (Camellia sinensis L.) plantations on a broader geographic scale as a model system. Based on amplicon sequencing and properties of 195 acidic (average pH = 5.0) soils, we determined the importance of proximal and distal regulation to N2O emissions. Microbial phylogenetic diversity as a distal regulator overwhelms mineral N content as a proximal regulator in explaining high N2O emissions. Low-abundance, diverse prokaryotic communities (e.g., Acidothermu) and specialized denitrifying fungal communities (e.g., Fusarium) were associated with high N2O emissions. Revisiting the impact of proximal regulators on distal regulators revealed that soil pH is the sole proximal regulator influencing the prokaryotic rare taxa that correlated with high N2O emissions. When considering proximal regulators together (here soil properties compiled as soil fertility index), the microbial diversity were independent of soil fertility. The microbial assembly was dominated by stochastic processes. Consequently, proximal regulators have a limited impact on distal regulators of N2O emissions from acidic soils. In conclusion, the framework underscored the importance of in situ microbial communities as distal regulators in explaining high N2O emissions from acidic soils.

Influence of primary tillage on some soil fertility indicators and corn yield

Influence of primary tillage on some soil fertility indicators and corn yield

Multifunctional N, Fe dual active site hydrothermal biochar for efficiently degrading paclobutrazol and promoting crop growth

The development of a low-cost, highly catalytic, and soil fertility-improving biochar material is of significant importance for the sustained remediation of organic pollutants in the environment. In this study, multifunctional N, Fe dual active site biochar (NF-BC) was successfully synthesized by hydrothermal method using cotton straw, urea, and FeCl3 as raw materials. Compared to the original biochar, NF-BC exhibits high graphitic-N content and abundant Fe2+, enabling efficient activation of Peroxymonosulfate (PMS) for the removal of Paclobutrazol (PBZ) in water and soil. EPR and quenching experiments confirm that the free radical pathway (•OH) and the non-free radical pathway (1O2) act together in PBZ degradation. The DFT results illustrate the benzene and pyridine rings of PBZ are electron-rich regions, which can be attacked by reactive oxygen species. Then three possible degradation pathways are provided by combining them with the LC/MS test. After remediation by the NF-BC/PMS system, the soil fertility index and plant growth are significantly improved. Compared to CK, the pH value and SOM content of the soil remained unchanged after remediation with the NF-BC/PMS system, while the content of available K and hydrolyzed N increased by 27.18 and 2.27 times, respectively. The pot experiments showed that the NF-BC/PMS system not only alleviates the stress of PBZ on mung bean seedlings, but also promotes an increase in leaf area, accumulation of dry biomass, and root growth. This work provides a new idea for the preparation of low-cost and multifunctional biochar for the efficient removal of pesticides in soil and water environments.

Soil Fertility and Bacterial Community Composition in Response to the Composting of Biochar-Amended Chicken Manure

Amidst the burgeoning expanse of the poultry sector, the escalation of chicken manure production has ensued, potentially exacerbating ecological contamination. However, the application of chicken manure is bound to transmute the habitat of edaphic microorganisms, precipitating an alteration in the soil’s microbial consortium. The composting of biochar-amended chicken manure and wood chips (biochar composting products, BCPs) was used to improve Chinese cabbage (Brassica campestris L.) production and regulate soil properties and bacterial community structure. On the 40th day of Chinese cabbage growth, soil and Chinese cabbage were collected for laboratory analysis. The effects of different proportions of BCPs (0, 1%, 3%, 5% and 7% biochar) on soil fertility, enzyme activity, the microbial community and the growth of Chinese cabbage were studied under facility conditions. The results showed that the growth performance and quality of Chinese cabbage were significantly increased with increasing BCP ratios. Soil fertility indicators including pH, AN, AP, AK and SOM were significantly increased, except for the pH value in the 1% BCP group. The activities of phosphatase, catalase and urease were increased for all groups of BCP treatment. The soil microbial community response was significantly different, and the application of 5% and 7% BCPs reduced the abundance, diversity and evenness of soil bacteria. Chinese cabbage growth performance was positively correlated with an increase in BCP supplemental levels in the range of 3–5%. Also, the abundance, diversity and uniformity of the soil microbial community were improved in the 3% BCP treatment group. Therefore, the dominant bacterial phyla were Bacteroidetes, Actinobacteriota, Gemmatimonadota, Myxococcota, Bdellovibrionota and Firmicutes, especially the Bradyrhizobium of Proteobacteria. BCP treatment reduced the degradation of soil organic matter. In addition, it also improved the relative abundance of sequences associated with improving soil fertility. Collectively, these findings offer insights for the re-evaluation of application management strategies for BCP organic fertilizers.

Development of Regenerative Tea Cultivation Models through Dual Approach of Soil and Plant Health Management towards Crop Sustainability, Soil Quality Development, Pesticide Reduction and Climate Change Mitigation: A Case Study from Lakhipara Tea Estate,

Climate change is a reality and its impact on the tea plantations is apparent in the rise of pest intensity, higher agrochemical use, inconsistent crop yields, declining grand growth period, increased abiotic stress and various other challenges; that threaten long-term sustainability of the Indian tea sector. The urgency to adopt sustainable practices is increasing by the day but to gain time bound results a comprehensive focus encompassing soil and plant health development will be crucial. To deal with climate challenge head-on, the Indian tea industry is making changes at various levels of operations. The sustainable tea initiative at Lakhipara tea estate, was one such attempt by the Goodricke Group Limited in their Dooars tea growing region of West Bengal. The program was initiated in 2014 with an aim to reduce pesticide use, improve soil quality, and produce quality teas while sustaining crop yields, improving renewable energy use and lowering the carbon footprint. Adoption of Inhana Rational Farming (IRF) Technology and taking the essence from ‘Trophobiosis Theory’ of French Scientist F. Chaboussou, the program focused on management of soil and plant health. Three years evaluation of crop yields in respect of the budgeted crop, revealed on an average an excess of 78 kg/ha/year in the project area. In rest of the garden area a contrasting crop loss of 118 kg was recorded per ha during the same period. The higher crop performance positively correlated with the higher nutrient use efficiency which was 17.7 percent higher in the project area (NUENPK : 8.86) as compared to the general garden area (NUENPK : 7.53), which reflected the impact of plant health management towards enhanced nutrient uptake, assimilation and utilization. Assessment of pesticide usage, revealed up to 77% decrease in usage in the project area during 2014-16, as compared to the pre- project year. Comparison with pesticide usage of the Dooars tea growing region during this same period, indicated a 62% lower Crop Pesticide Pollution Index (CPPI) in the project area. The finding indicated a 52 to 77% reduction in the accumulated toxicity potential of the applied pesticides in the project area; thereby accrediting safer tea development under this program, when adjudged in terms of pesticide residue. Assessment of soil quality revealed an overall eight percent increment in Soil Fertility Index (FI) value, with significant improvement in soil microbial activity potential (MAP) values i.e., by almost four times. The finding pointed towards the favourable impact of soil health management primarily through Novcom composting towards enhancement of soil microbial interactions. Post three years of experimentation the overall Soil Quality Iindex (SQI) value increased by 6% in the project area. The finding corroborated a concurrent 6.72% increase in the soil organic carbon stock during the same period. Reduction in use of non- renewable inputs viz. chemical fertilizers and pesticides in the project area was indicated by approximately 40 percent enhancement in energy use efficiency and energy productivity post the assessment period. Carbon assessment in terms of kg CO2 equivalents/ kg made tea (using ACFA version 1.0) indicated approx. 65 to 70 % lower footprint in the project area, primarily due to 20 to 30 % reduction in chemical fertilizers and 60 to 70 % reduction in the use of synthetic pesticides. The results indicated that while integrated soil management is the pre-requisite criteria towards rejuvenation of soil health and for restoration of the habitat for predators, it does not play a direct role in reducing the pest pressure and simultaneously the requirement of pesticides. Physiologically activated plants/ bushes on the other hand; due to their higher nutrient assimilation capacity and efficient protein synthesis are always lesser susceptible to pest attack. Hence, focus on activation of plant physiology can reduce the plant- pest interaction leading to a natural reduction in the requirement for pesticides vis-à-vis the pesticide usage.

Effects of Organic Amendments and Mineral Fertilizers on Optimizing Nutrient Cycling in Alkaline Soil

Soil microbial biomass carbon (MBC) and nitrogen (MBN) are indicators of microbial size and soil fertility, representing a vital living nutrient reservoir in the soil. This study aimed to evaluate the impact of various organic sources, such as poultry manure (PM), farmyard manure (FYM), compost (CM), and biochar (BC), along with different levels of mineral fertilizers on soil microbial dynamics and nutrient (N, P) mineralization through laboratory incubation experiments. The organic amendments were applied at rates of 0.25%, 0.5%, and 1.0% of soil carbon (w/w), combined with 75%, 50%, and 25% of recommended doses of NPK (120:90 and 60 kg N, P2O5, and K2O ha-1), respectively. Following the application of amendments, the soil underwent a 16-day incubation period to measure CO2 emissions and a 28-day period for N and P mineralization. The rate of CO2 evolution exhibited a significant increase with higher carbon levels but declined over time. Compost showed the highest CO2 evolution at any given time, followed by PM, FYM, and BC, likely due to a higher readily available fraction of carbon. Compost, particularly at the 1% C level in combination with inorganic fertilizer, led to a significant increase in soil microbial biomass C and N. Nitrogen and phosphorous mineralization increased with the duration of the 28-day incubation period. However, the net release of N and P decreased with higher carbon levels, potentially associated with both immobilization and the fact that higher levels received lower (25%) NPK levels. Nevertheless, soils treated with CM and PM maintained higher levels of N and P, associated with their higher fraction of labile nutrients. These findings suggest that the continuous application of organic sources enhances N and P mineralization, soil microbial biomass, and their activity. Therefore, the regular application of carbon sources emerges as a strategic approach to improving the soil health of less fertile alkaline calcareous soils.

Some Indicators of Soil Fertility in the Central Aran Economic Region of Azerbaijan

Diagnostic indicators of selected soil types in the Central Aran economic region are presented and analyzed based on the soil map of Azerbaijan M: 1:100000 2022. The areas of reclaimed, irrigated, and also possible lands of the Kura-Araz Lowland for agricultural use have been identified. Data on fertile soils are provided. Full descriptions of 11 soil types are given. The main diagnostic indicators are given using the example of gray-brown and meadow-gray soils.

Potential of Chromolaena odorata, Ipomoea carnea and Eichhornia crassipes as green manures on soil fertility index and rice production on vertisols

Potential of Chromolaena odorata, Ipomoea carnea and Eichhornia crassipes as green manures on soil fertility index and rice production on vertisols

Physical and Chemical Properties of Cocoa Pod Husk Dumpsites in Etung Cocoa Farms Nigeria

Assessment of some physical and chemical properties of cocoa pod husk dumpsites in Etung, Nigeria, was carried out to ascertain the particle size distribution, nutrients, and some soil fertility indices. Five cocoa-growing communities were purposely selected for sampling. Soil samples were collected at 0–25 cm and 25–50 cm in each cocoa farm dumpsite and non-dumpsites in the cocoa plantations. A total of 20 samples were collected, processed, and subjected to standard laboratory analysis. The results obtained indicated that there was no difference in soil textural classes between dumpsites and non-dumpsites on the plantations. pH in dumpsites ranged from 4.2 to 6.0, and plantation soils ranged from 3.9 to 5.6 Electrical conductivity. Surface dumpsite soils ranged from 0.0068 to 0.941 ds/m, and plantation soils ranged from 0.084 to 0.0816 ds/m. Total N in dumpsites ranged from 1.14–1.98% and 0.73–1.08% in plantation soils. P in dumpsites ranged from 9.61 to 13.42 mg/kg and 5.98 to 11.34 mg/kg in plantation soils. Exchange cations were higher in dumpsites than plantation soils. The students T-test (t-0.05) showed significantly higher pH, N, P, organic C, and CEC in dumpsite sites than plantation soils and significantly higher surface than subsurface soil depth. Though nutrient levels were higher in cocoa pod husk dumpsites, the levels were within the sufficiency threshold levels. The higher organic carbon content of cocoa pod husk dumpsites is an indicator of higher soil organic matter content for good sorption and retention of both macro- and micro-cationic nutrients to prevent their excess release that could degrade the soils.

Rescuing local knowledge with regards to soil management and fertility in the Amazon Region of Ecuador

Sustainable soil management methods that consider farmers' needs and soil conservation, require the integration of scientific knowledge and farming practices. Therefore, this study has asked a. How do farmers perceive fertility indicators in relation to their management in agriculture? b. What strategies do small farmers implement to maintain soil health on their farmland? c. Are there correlations between scientific findings and farmers' perceptions of soil management indicators and practices in the Ecuadorian Amazon? A total of 287 surveys were applied with 35 questions that covered the general data of the respondent, visible indicators of soil fertility, soil management and conservation practices, as well as knowledge acquisition. The soil scientific data were obtained from the map made by the MAG and FAO (2018) of the locations where the surveys were conducted. The results show that farmers have an in-depth knowledge with respect to soil fertility, identifying several visible indicators, including some plants that indicate productive soils, while utilizing various practices that degrade the soil and others that contribute to soil conservation at the local level. Although the indicators used by the farmers were mainly based on observation, in many respects they coincided with scientific assessments of fertile or infertile soils. These farmers, with their vast practical experience and knowledge accumulated over generations, developed a deep understanding of the telltale signs of soil fertility. There is not always concordance between the two forms of knowledge, however, the synergy between traditional and scientific knowledge illustrates the importance of integrating different forms of knowledge for effective and sustainable land management.

Do We Listen or Ignore Indigenous Practices? The Machobane Farming System - An Indigenous Farming Practice of Lesotho

Aim: To evaluate the adaptive capacity of the Machobane Farming System, an indigenous practice to improve soil fertility and maize productivity compared to other non-Machobane farming practices. Study design: The study was conducted in four agroecological zones of Lesotho: Mountain, Foothills, low lands and Senqu river valley. Soil samples were collected at random from the non-Machobane farming practicing fields and Machobane farming practicing fields and the soil physicochemical and microbiological analyses were conducted to evaluate the soil quality. Structured and non-structured questionnaires were used to gather information from Focus Group Discussion (FGD) on the type of farming practices used and other demographic data. Results and Discussion: The MfS were found to be less affected and resilient to climate change with multiple benefits such as moisture conservation, slow release of nutrients and cross migration of microorganisms to the intercropping plants in the field unlike other farming practicing fields. An increased number of soil fertility indicator microorganisms such as Bacillus spp and Nitrogen fixing bacteria were seen to have increased the production of food crops (P&gt;0.05) almost all the year round. An intensive relay cropping of one acre would be sufficient to ensure food security for an average family of 5 members. Conclusion: Currently, the Machobane Farming System (MfS) is adopted by many households in Lesotho using biochar and compost.

Can soil health in degraded woodlands of a semi-arid environment improve after thirty years?

In natural habitats, especially in arid and semi-arid areas that are fragile ecosystems, vegetation degradation is one of the most important factors affecting the variability of soil health. Studying physicochemical and biological parameters that serve as indicators of soil health offers important information on the potential risk of land degradation and the progression of changes in soil performance and health during recovery periods. This study specifically examines the impact of vegetation degradation on soil health indicators and the duration needed to improve the physical, chemical, and biological parameters in a semi-arid mountainous area site types with the dominance of Quercus macranthera Fisch & C.A. Mey and Carpinus orientalis Miller in northern Iran. In different years (2003, 2013, and 2023), litter and soil samples (at depths of 0–10, 10–20, and 20–30 cm) were collected in different types of degraded sites. Additionally, in 2023, a non-degraded site was chosen as a control and similar samples were collected. A total of 48 litter (12 samples for each of the study site types) and 144 soil (4 study site types × 3 depths × 12 samples) samples were collected. In order to investigate the spatial changes of soil basal respiration (or CO2 emission), which is involved in global warming, from each site type, 50 soil samples were taken along two 250-meter transects. The findings showed that litter P and Mg contents in the non-degraded site were 1.6 times higher than in degraded site types (2003). Following vegetation degradation, soil fertility indicators decreased by 2–4 times. The biota population was lower by about 80 % under the degraded site types (2003) than in the non-degraded site, and the density of fungi and bacteria in the degraded site types was almost half that of the non-degraded site types. Geostatistics showed the high variance (linear model) of CO2 emissions in areas without degradation. In addition, vegetation degradation significantly reduced soil carbon and nitrogen mineralization. Although soil health indicators under the degraded vegetation have improved over time (30 years), results showed that even thirty years is not enough for the full recovery of a degraded ecosystem, and more time is needed for the degraded area to reach the same conditions as the non-degraded site. Considering the time required for natural restoration in degraded site types, it is necessary to prioritize the conservation of vegetation and improve the ecosystem restoration process with adequate interventions.

Main drivers of productivity of Acacia mangium plantations in Vietnam

Acacia mangium is one of the most important hardwood plantation species in the tropics. The question of how to grow Acacia productively and sustainably remains a major issue for the forestry sector in many tropical countries. We analyzed the productivity of A. mangium plantations across five contrasting ecological zones in Vietnam. These covered gradients in rainfall from 1750 mm to 3060 mm and a mean annual temperature range of 22 – 27 0C. Plantation productivity across these zones varied from an MAI of 6 m3 ha y−1 to 31 m3 ha y−1. A comprehensive suite of statistical methods was utilized for variable and model selection to minimize confounding and multicollinearity issues among predictors and identify determinants of plantation productivity using 27 biophysical variables. These variables encompass plantation age, climate parameters, as well as site and soil properties. Results showed that, apart from plantation age, the factors influencing plantation productivity and explaining a majority of variation in mean annual timber increment are soil organic carbon content and the number of foggy days. Soil carbon is probably an index of overall soil fertility and its significance reflects the fact that the plantations have often been established on relatively degraded sites. The lower productivity at sites having a higher frequency of foggy days (up to 57 days per year in some regions) may arise from lower solar radiation and temperature during fog. The results of this study can inform site selection and plantation management tools aimed at maximizing Acacia mangium productivity in Vietnam and other countries with similar ecological conditions. Planting A. mangium in high-intensity fog areas is not recommended. Further studies on the ecophysiological mechanisms of how fog influences the growth of tropical A. mangium plantations are also needed.