Current re-vegetation patterns and restoration issues in degraded geological phosphorus-rich mountain areas:A synthetic analysis of Central Yunnan, SW China

China has the largest area of inland geological phosphorus-rich(GPR) mountains in the world, where vegetation restoration is key to safeguarding the environment. We reviewed the published literature and collected new data in order to analyze re-vegetation patterns and the status of plant communities in central Yunnan. The aim of our analysis was to suggest future improvements to restoration strategies in GPR mountain regions. Our results showed that spontaneous recovery was the most widespread type of restoration. N-fixing species such as Coriaria nepalensis and Alnus nepalensis play a vital role in succession. In the past, monoculture tree plantation was the primary method used in afforestation activities in central Yunnan; in recent years however, several different methods of restoration have been introduced including the use of agroforestry systems. For practical restoration, we found that spontaneous recovery was capable of delivering the best results, but that during its early stages, restoration results were affected by several factors including erosion risk, the origin of propagates and environmental variation. In contrast, methods employing human-made communities performed better in their early stages, but were constrained by higher costs and vulnerability to degradation and erosion. The use of N-fixing species such as A. nepalensis and Acacia mearnsii in plantations were unsuccessful in restoring full ecosystem functions. The success of restoration activities in GPR mountain regions could be improved through the following measures:(1) developing a better understanding of the respective advantages and disadvantages of current natural and human-engineered restoration approaches;(2) elucidating the feedback mechanism between phosphorus-rich soil and species selected for restoration, especially N-fixing species;(3) introducing market incentives aimed at encouraging specific restoration activities such as agroforestry, and improving the industry value chain.

Lost in transition： Forest transition and natural forest loss in tropical China

The term forest transition refers to a change in forest cover over a given area from a period of net forest area loss to a period of net gain. Whether transitioning from deforestation to reforestation can lead to improved ecosystem services, depends on the quality and characteristics of the newly established forest cover. Using publicly available data, we examine forest transition in two regions of tropical China: Hainan Island and Xishuangbanna. We found that the overall increase of forest cover in both areas during the1980 s was due to an increase in plantation forests rather than to increases in the area covered by natural forest. We also found a time lag between the increase in overall forest cover and an increase in natural forest. On Hainan Island, natural forest continued to decline beyond the point in time when overall forest cover had started to increase, and only began to recover ten years after the turning point in 1978. In Xishuangbanna, where the transition point occurred ten years later, the decline of natural forest cover is still going on. These divergent trends underlying forest transition are concealed by the continued practice to apply the term "forest" broadly, without distinguishing between natural forests and planted forests.Due to the use of undiscriminating terminology, the loss of natural forest may go unnoticed, increasing the risk of plantation forests displacing natural forests in the course of forest transition. Our findings are important for programs related to forest management and ecosystem services improvement, including reforestation and Payments for Ecosystem Services programs.

Nutrient value of wild fodder species and the implications for improving the diet of mithun (Bos frontalis) in Dulongjiang area, Yunnan Province, China

Wild fodder plants are valuable because they provide an important livestock feed resource globally,especially for smallholder farmers,and have important roles in natural resource management.In-depth knowledge of wild forage plants can motivate local people for feed resource and habitat conservation of threatened herbivores such as Mithun(Bos frontalis).Mithun occur in small patches in the mountains of Dulongjiang,nearby villagers domesticated this animal but left animal to freely graze in the mountains.Many fodder plants occur in these mountains,however,little is known about their nutritional value.We conducted an ethnobotanical survey to document important wild fodder plants consumed by mithun in the Dulongjiang Township.The nutritional content of 21 highly mentioned wild fodder plants in an ethnobotanical survey was examined.Laboratory analysis showed that Fagopyrum dibotrys were the fodder species with the highest crude protein(CP)content(26.89%),followed by Polygonum molle(21.88%)and Hydrangea longipes(21.12%).Synthesis of relative feed value index and grey relational grade,P.molle,H.longipes and Tetrastigma obtectum were ranked the top three nutritional fodders.There was a significant difference between 21 species on their in vitro digestibility and the most highly digestible fodder species was Elatostema hookerianum.Linear model analysis on relationship between frequency of citation of 21 wild forage plants by local farmers and their nutrient composition showed that the frequency was significantly positively correlated with the nutritional value of the feed(R2?0.28,P<0.05).We concluded that these species have high nutritional values to improve mithun production in integrated crop-livestock systems.Fodder species or mixtures of species with useful nutritional characters could be cultivated to improve livestock productivity,habitat conservation including that of mithun and wild forage resource management.

Morphology, Phylogeny and Culture Characteristics of Ganoderma gibbosum Collected from Kunming, Yunnan Province, China

Ganoderma is a genus of medicinally and economically important mushrooms in the family Ganodermataceae.Ganoderma species are popular medicinal mushrooms and their health benefits are well-documented.Ganoderma is a cosmopolitan genus that is widely distributed in both tropical and temperate regions.This genus is characterized by its unique laccate or non-laccate species with double-walled basidiospores.Here,we report on eight collections of G.gibbosum collected during surveys in Kunming,Yunnan Province,China.The specimens are described and illustrated based on macro-and micro-morphological characteristics.Total DNA of the eight G.gibbosum strains were extracted using the Biospin Fungal Extraction Kit following manufacturer protocol.Amplification of the Internal Transcribed Spacer(nrITS)region was carried out using ITS5/ITS4 primers and LROR/LR5 for the nuclear ribosomal large subunit 28S rDNA gene(LSU).Phylogenetic analysis with closely related species to G.gibbosum showed that all eight collections grouped with G.gibbosum with 100%bootstrap support.Phylogenetic similarity and morphological variations within the eight collections of G.gibbosum are discussed.

Global carbon sequestration potential of agroforestry and increased tree cover on agricultural land

Biomass is fundamental to circular agricultural systems.Estimates of above-and below-ground biomass on agricultural land based upon IPCC Tier 1 estimates are compared with an updated carbon density map based on remote sensing,with results indicating the methodology and initial estimations are robust.Two scenarios are evaluated to estimate carbon sequestration potential of increasing tree cover on agricultural land:1)incremental change and 2)a systemic change to agroforestry.Estimates of above-and below ground biomass carbon were combined with a tree cover analysis to estimate the increase in biomass.Global increases(4−6 PgC for incremental change;12−19 PgC for systemic change)highlight substantial mitigation potential.Increasing global tree cover on agricultural land by 10%would sequester more than 18 PgC.South America has the highest potential,followed by Southeast Asia,West and Central Africa,and North America.Brazil,Indonesia,Philippines,India,the United States and China are among the top countries with the highest carbon sequestration potential on agricultural land with increased tree cover.

An Overview of the Problems and Prospects for Circular Agriculture in Sustainable Food Systems in the Anthropocene

In this overview paper,we outline and explore problems and prospects for circular agriculture’s contributions to transformative change toward sustainable food systems in the Anthropocene.We define circular agriculture(CA)and provide historical context on its development.We then discuss how CA can contribute to food system transformations in four key areas:multi-functional landscapes;sustainable intensification(focusing on nitrogen/crop-livestock management and digital agriculture);smallholder farmers;and dietary change.We find that food systems transitions will be challenging due to the depth,scale,and speed of changes necessary for humans to remain within safe planetary boundaries out to 2050.

Deciphering microplastic ecotoxicology:impacts on crops and soil ecosystem functions

Review on microplastic toxicity in agroecosystems is scarce.Thus,we develop a conceptual model(based on literature to date)that describes various microplastic effects using a size-scale.We also classify crops depending on their observed responses,and discuss several conceptual mechanisms of soil functions.The model shows that microplastic effects on crops can be positive,toxic,lethal and no-effect.Predominantly,microfibers in a wide range of sizes can positively affect crops.However,toxic effects of microplastics with/without other pollutants are more common at different sizes.Surprisingly,biodegradable plastic effects are lethal,calling into question their environmental friendliness.No-effect on crops is also possible but less observed.Unlike other crops(e.g.,wheat,maize and bean),only onion seems resistant to microplastics.Crop uptake of micro/nanoplastic demands a clear benchmark to ensure food-safety.Furthermore,mixed effects are observed on soil functions.Alternation in soil enzymes and litter decomposition can affect nutrients and organic matter biogeochemistry.Hydrophobicity can be induced by increasing evaporation.Shifts in microbial community structure and activities are inevitable.

Mapping tree species distribution in support of China's integrated tree-livestock-crop system

The primary challenge of the contemporary world is to meet accelerating requirements for food.Limited land,competition between crop and livestock farming and climate change are major challenges.Agroforestry offer a form of sustainable agriculture through the direct provision of food by raising farmers’incomes and through various ecosystem services.The first essential step in adopting agroforestry is the selection of appropriate tree species that fit local climates.In this paper,we mapped 20 fodder trees and important crops in China using the multi-model ensemble and Ecocrop modelling approach.Relying on the intersectional concept of set theory,the fuzzy logic technique was applied to identify regions where candidate trees could be grown with appropriate crops and livestock.The resulting models provide important insights into the climatic suitability of trees and crops and offer knowledge critical to the proper integration of trees with crops and livestock at specific locations.The results offer support for developing appropriate strategies regarding potential land-use within agroforestry systems in order to maximize ecosystem services and the benefits of sustainable agriculture.Model outputs could easily convert into conventional maps with clearly defined boundaries for site-specific planning for tree-crop-livestock integration.The next step for actualizing an integrated system is to investigate specifically what these different species may contribute to the existing farming systems,quantify the benefits and estimate any possible tradeoffs.

Arbuscular Mycorrhiza and Sustainable Agriculture

Arbuscular mycorrhizal fungi(AMF)provide benefits to most crop species via enhanced nutrient uptake,increased drought and abiotic stress resistance,and reduced effects of pathogens and pests.Much remains unclear regarding the specific mechanisms influencing these processes,and the critical roles of AMF are often overlooked in planning agroecological systems.There is growing consensus,however,around the important roles AMF play in improving plant resilience and crop yield while also enhancing the functioning of soil microbial communities.Heterogeneous practices across all scales complicate the successful integration of AMF in agroecological systems.AMF symbioses with crops are passive,or stimulated by incorporation of crop wastes in soil,soil inoculation with AMF spores,or the planting inoculated of seeds.Here we suggest that AMF can have highest beneficial impacts in areas with low levels of agrochemical inputs.We argue that areas with intensive agrochemical inputs can also be made more sustainable with AMF enhancements.

A New Record of Aspergillus vadensis (Ascomycota) Isolated from Soil in Yunnan Province,China

During a survey of soil fungi in Yunnan Province,several isolates of Aspergillus were obtained.Based on morphology and molecular analyses of internal transcribed spacer regions and intervening 5.8S nrRNA gene(ITS),β-tubulin and calmodulin(CaM)genes sequences,two isolates were identified as Aspergillus vadensis(section Nigri).A phylogenetic tree,detailed descriptions,illustrations and scanned electron microscopy morphology are provided for the new isolates.This is the first record of A.vadensis from China.

A review of bambusicolous Ascomycota in China with an emphasis on species richness in southwest China

Bamboos not only provide socio-economic benefits to communities within the region,but also provide ecosystem services such as soil-water conservation,stabilization of sandy soils and restoration of soil nutrients.Bambusicolous ascomycetes refer to ascomycetous fungi living on any substrate of bamboo.As the largest group of fungi on bamboo,they play a significant ecological value in species composition and the structure of the fungal community,circulation of materials and energy flow of nutritional elements.In an effort to document the bambusicolous Ascomycota found in China,we assessed all major sources of academic literature,journal papers,and the USDA database(https://nt.ars-grin.gov/fungaldatabases/fungushost/fungushost.cfm)for reports of these fungi from China.As a result,we produced a systematic and comprehensive checklist of bambusicolous Ascomycota in China.Current names of fungi,bamboo host name,bamboo substrate,details of collected localities,references and latest classification for every bambusicolous ascomycete in China are also provided.In addition,we focused on the species richness of bambusicolous Ascomycota in China with an emphasis on southwest China.

The Awassi sire can be used to crossbred with low-productive Tikur local ewes to produce export-marketable weight at yearling under farmer's management in the Ethiopian highlands

A community-based sheep cross breeding project was conducted in Ethiopia with exotic Awassi crossbred rams and less productive indigenous Tikur ewes.Fifty-five Awassi crossbred rams having 46,48,56 and 65%Awassi blood levels were purchased and distributed to the participating 84 farmers which had 2,884 breeding ewes.The overall least square mean weights for F1 and F2 generation lambs at birth,day 90,180,270 and yearling weight were 3.10±0.01,13.04±0.07,16.95±0.08,20.84±0.11 and 24.42±0.14 kg,respectively.Body weight traits were significantly affected by lambing year for birth weight(P<0.05),180-day(d)weight(P<0.05),270-d weight(P<0.001)and 360 d(yearling)weight(P<0.001)but no effect(P>0.05)was noted for 90-d weight(weaning weight).Season of lambing had significant effect(P<0.01)only for birth weight.There was a significant difference(P<0.001)among the different villages for birth weight,and for day 90,180,270 and 360 body weights.The study showed that crossing Awassi crossbred rams with Tikur ewes can improve birth weight by 71.27%,90-d weight by 76.78%,180-d weight by 63.45%and yearling weight by 76.06%under farmer management practices.Results revealed that crossing Awassi crossbred rams with blood level of 56%and above with local Tikur ewes resulted in superior progenies that can fulfill export live weight standard of 25 kg at yearling weight.The future of Awassi-Tikur sheep farming must focus on feed supplementation strategies and on establishing cooperatives for farmers to improve their livelihoods.

Bio-catalyzed plastic degradation:a review

The widespread use and production of plastic have led to increased accumulation of plastic waste in the environment which threatens terrestrial and marine life.Efficient methods for management of plastic waste remain a key challenge.Biodegradation of plastics is considered an environmentally safe method,but is still limited to laboratory scale.Several previous studies have reported microbial enzymes capable of degrading plastic.These discoveries offer a promising starting point for the development of biocatalyzed plastic degradation technology.In this review,we discuss recent advancements and applications of biocatalyst technology.We also describe the different steps for development of biocatalyzed plastic degradation technology and the major issues related to each stage.Breakthroughs in research into biocatalyzed plastic degradation would lead to new opportunities for sustainable alleviation of the worldwide problem of plastic waste accumulation.

Trees as hotspots:Using forests,trees,and agroforestry to foster diverse sustainable landscapes

Forests,trees,and agroforestry(FTA)are ecosystem hotspots.They exemplify the contributions of biodiversity to sustainable and resilient landscapes,green circular economy and to sustainable agriculture and food systems for healthy diets.However,most research on these topics have been performed separately and lack comparison.The International FTA-Kunming Conference'Forests,trees and agroforestry for diverse sustainable landscapes'22nd–24th June 2021,focused on these contributions,brought together scientists NGOs,and policy makers to further the understanding of tree diversity;provided a communication platform for scientists to share their research results;evaluated the role of tree diversity in agroecology and circular agriculture;assessed benefits of landscape restoration;and explored applied research in mountain ecosystems and food security.The goals were to gather evidence that ground the design of solutions that can contribute to the implementation of the post 2020 Global Biodiversity Framework and towards the UN Food Systems Summit,and the overall implementation of the SDGs.This paper summarizes the outcomes of the international FTA Conference in Kunming 2021 and points out the highlights of research involved in six major themes.

A circular approach for sustainable agriculture and human health

In the 21st century,global food systems cannot remain stuck in the past.Agriculture currently contributes about one fourth of global greenhouse gas emissions and about half of all nutrient wastes annually[1].As the number of humans on the planet continues to grow,the effects of climate change will worsen and ecosystems will continue to deteriorate.Innovation in today’s agricultural food production systems is therefore urgently needed to increase crop and animal outputs,enhance dietary diversity and improve human health while conserving environments and sustaining natural resources and cultures.

Towards a comprehensive understanding of free-living nitrogen fixation

Free-living nitrogen fixation(FNF)is a ubiquitous phenomenon that plays a modest role in the(N)economy of an ecosystem.However,sampling difficulties,methodological constraints and environmental controls have presented challenges for predicting the actual rate of FNF.Therefore,a deeper understanding of the accuracy to design models that consider dynamics,heterogeneity,influences,and other limitations is needed.This review presents an overview of the biology and diversity of microorganisms related to FNF as well as various ecological controls that influence these microorganisms.We also discussed contributions of FNF to the N input of various ecosystems.Overall,previous research has shown that considerable spatiotemporal variability exists in microbial types at both biome and microbiome scales,resulting in significant variation in FNF.Beyond this,rate of FNF is controlled by certain factors,such oxygen and metal ion availability,source of energy and soil nutrients,temperature,and pH.Empirical evidence increasingly indicates a significant contribution of FNF to N inputs in natural,agricultural,and aquatic ecosystems.It is inferred from this review that for the expanded exploitation of biological nitrogen fixation(BNF),we must pay additional attention to FNF because it occupies a central role within the process.Finally,we propose a framework for the quantification of FNF alongside a suite of recommendations that would deepen our understanding of FNF.

Root symbioses as belowground C pumps:a mitigation strategy against rising CO_(2)levels

Mycorrhizal and N-fixing root symbioses evolved at two points in the past when global CO_(2)was highest,consistent with the high demand these symbioses place on host C.Trees hosting both mycorrhiza and N-fixing bacteria are able to fix more atmospheric CO_(2)and grow at faster rates than non-symbiotic plants,or plants with only mycorrhiza.We argue that on the basis of this improved C capture,N-fixing trees act as C-pumps,sequestering C and locking it in biomass,thus,if properly managed,can contribute significantly towards the mitigation of rising CO_(2)levels.

Mushroom as a means of sustainable rural development in the Chin State,Myanmar

Restricted access to quality crops and markets limits the capacity of rural communities to generate income in the mountainous regions of South and Southeast Asia,often resulting in the exploitation of forest systems,a subsequent decline in forest health,and the need for alternative means of income generation as well as forest restoration programmes.Cultivation of edible and medicinal mushrooms has been shown to be a feasible alternative source of income and also contributes to the household nutrition of rural and impoverished communities.There are a number of ongoing programmes in South and Southeast Asia currently implementing trainings and demonstrative practices for the cultivation of mushrooms at the village level.In this context,we implemented different cultivation strategies in selected rural areas in the Chin State,Myanmar.The cultivation strategies were to 1)introduce mushroom cultivation using locally sourced raw materials as substrates for rural communities unfamiliar with mushroom cultivation;and 2)improve the technical knowledge of those already experienced in mushroom cultivation in order to increase yield and minimize challenges in production systems.We introduced Pleurotus sp.cultivation to mushroom growers in the Chin state,Myanmar.These cultivation strategies will help further improve and develop mushroom industries in rural areas and contribute to rural development.In addition,we focused on cultivation systems that incorporate the use of crop residues and woody substrates in order to ensure a sustainable,integrated approach.

Valorizing plastic waste by insect consumption

Insects first began evolving hundreds of millions of years ago,and aided by gut microbes,they have been consuming hydrocarbon polymers ever since.Few man-made plastic polymers are chemically novel,so it is reasonable that insect/microbe systems can be found or developed to degrade them rapidly.However,remediation of global plastic waste problems should involve more than just conversion into CO_(2).Some industryscale microbial enzymatic degradation of plastic polymers may yield valuable monomers,but the plastic waste starting material must be of uniform chemistry and clean.This adds cost to the process.Many insect species can be utilized for animal feed as well as human food.Some of these insects have the capability to degrade plastic polymers.However,valorizing plastic wastes by producing edible insects or useful frass has largely been overlooked.Here we assemble the current knowledge of plastic degradation rates by insects.In addition,we also show the first instance of insect degradation of polyurethane and the first identification and isolation of insect gut fungi as directly aiding insect degradation.

Effects of vegetation type and soil horizon on soil bacterial and fungal communities in a dry–hot valley

Soil horizon and vegetation cover significantly impact the spatial patterns of soil fungal and bacterial communities.However,such impacts and their interactions are poorly characterized in dry–hot environments.Soil samples were collected from two soil horizons(humus and mineral)along a vegetation gradient(shrubland,grassland,and shrub–grass ecotone)in a dry-hot valley of Southwestern China to assess the effects of vegetation versus soil horizons on shaping soil microbial communities.We used denaturing gradient gel electrophoresis to estimate the microbial spatial pattern change across the vegetation gradients and clone libraries targeting small subunit rRNA genes to characterize the microbial community structures between distinct vegetation types and soil horizons.Bacterial DNA profile patterns were not significantly different across vegetation types but strongly correlated with soil horizons,with significant interaction effects.By contrast,fungi were remarkably different across vegetation types and soil horizons,without significant interactions effect.Distinct vegetation types did not necessarily harbor distinct bacterial or fungal community compositions.Rather,both community compositions were most strongly affected by the soil horizons.Together with these results,the soil vertical heterogeneity rather than vegetation changes is suggested to best predict shifts in soil microbial communities in this dry-hot valley area.