Impact of grazing on soil, vegetation and ewe production performances in a semi-arid rangeland

Controlled grazing is considered a good management strategy to maintain or increase the live weight of livestock and to reduce vegetation degradation of rangelands. The present study investigated soil characteristics, aboveground vegetation biomass dynamics and controlled grazinginduced changes in the live weight of local ewes in the semi-arid rangeland of Ahmadun, Ziarat, Balochistanprovince of Pakistan. An area of 115 ha was protected from livestock grazing in April 2014. In June 2015, soil characteristics within 0-30 cm depth i.e. soil organic matter(SOM), mineral nitrogen, p H and texture in controlled and uncontrolled grazing sites were assessed. Aboveground vegetation biomass measured in early(June) and late summer(August) in 2015 and 2016. The nutritional value i.e. crude protein, phosphorus(P), neutral detergent fiber(NDF), acid detergent fiber(ADF), calcium(Ca), magnesium(Mg) and potassium(K) of dominantplant species were assessed at the beginning of experiment in 2015. Vegetation cover of controlled and uncontrolled grazing sites was also measured during the two years of the study period using the Veg Measure software. From June to November in2015 and 2016, controlled and uncontrolled livestock grazing sites were grazed on a daily basis by local ewes with a stocking rate of 2 and 1 head ha^(-1) respectively. Results reveal that the organic matter contents of coarse-textured, slightly alkaline soil of the study site were in the range of 9.4-17.6 g kg^(-1) soil and showed a strong positive correlation with aboveground vegetation biomass. The biomass of plants was 56.5% and 33% greater at controlled than uncontrolled grazing site in 2015 and 2016 respectively and plant cover was also higher at controlled than uncontrolled grazing site in both years The nutrient contents were significantly(P<0.05)lower in grasses than shrubs. In both years, the controlled grazing increased the weight gain of ewes about two folds compared to the uncontrolled grazing.The results indicate that controlled grazing improved the vegetation biomass production and small ruminant productivity.

Mitochondrial DNA diversity and origin of indigenous pigs in South China and their contribution to western modern pig breeds

Indigenous pigs in South China are valuable genetic resources with many specific and unique characters, which have played an important role in the establishment of some western modern pig breeds. However, the origin and genetic diversity of indigenous pigs in South China have not been fully understood. In the present study, we sequenced 534 novel mitochondrial DNA (mtDNA) D-loop and assembled 54 complete mitogenome sequences for all 17 indigenous pig breeds from Fujian, Guangdong, Guangxi and Hainan in South China. These data were analyzed together with previously published homologous sequences relevant to this study. We found that all 13 coding genes of the mitogenomes were under purifying selection, but ND1 had the most variable sites and CYTB contained the most non-synonymous SNPs. Phylogenetic analysis showed that all indigenous pigs in South China were clustered into the D haplogroup with D1a1, D1b, D1c and D1e sub-haplogroups found to be dominant. Haplotype and nucleotide diversities of D-loop sequences ranged from 0.427 to 0.899 and from 0.00342 to 0.00695, respectively, among which all pigs in Guangdong had the lowest diversity. The estimates of pairwise FST, gene flow (Nm) and genetic distance (Da) indicated that most of these indigenous pig breeds differentiated from each other significantly (P<0.05). Among the western modern breeds, Berkshire and Yorkshire had significant Asian matrilineal footprints from indigenous pigs in South China, especially the Spotted pigs distributed in Guangdong and Guangxi. The neutrality test (Fu’s FS) indicated that indigenous pigs from Fujian and Guangxi had gone through recent population expansion events (P<0.05). It is concluded that indigenous pigs in South China were most likely derived from the Mekong region and the middle and downstream regions of Yangtze River through Guangxi and Fujian. Our findings provide a complete and in-depth insight on the origin and distribution pattern of maternal genetic diversity of indigenous pigs in South China.

Factors Affecting Arab Goat Flock Dynamics in Western Lowlands of Ethiopia

The study was conducted to estimate flock dynamics of western lowland Arab goat and to assess their contribution to income of smallholder farmers in Kurmuk and Assosa districts, western Ethiopia. Flocks of 30 households were monitored for a period of 12 months in 2016. Data were analyzed using the general linear model procedure of SAS and two-way interaction effects were fitted in the model and retained when found significant in the preliminary analysis. The study result indicates that total entrances for all flock were significantly (p < 0.05) higher in dry and hot-cool seasons than wet season. Most of the entrance was kids born in hot-cool season (January) (4.0 ± 0.42) and hot-dry season (May) (5.4 ± 1.09) for Assosa and Kumruk study sites, respectively. Kid mortality constituted the greater part of outflow. High kid mortality was occurred during July, February, January, and September. Most of the sell of castrated goats were occurred in September and April for both small and large flocks targeting holidays celebrated during this months. Male goat owners had significantly lower goat production potential (GPP) value than female (0.47 ± 0.02 vs. 0.52 ± 0.02). The GPP was lower in small flock than in large flock (0.48 ± 0.02 vs. 0.51 ± 0.02). Higher GPP was recorded in the months of January, February, and March for both large and small flocks. The off-take was higher (P < 0.05) in Assosa (0.06 ± 0.01) than Kumruk (0.02 ± 0.02) district. The average goat production efficiency (GPE) was higher (P < 0.05) in Assosa large (193.23 ± 20.0) and small flocks (93.44 ± 17.3) than Kumruk large (84.71 ± 15.6) and small flocks (33.33 ± 26.3).The production efficiency recorded was not comparable to the potential that the farmers had to sell goats or consume goats’ meat and milk. The lower goat production potential observed for small flocks implies that high mortality rates severely restrict receiving higher benefits from goat. Therefore, in order to optimize the productivity of goats flock dynamics, developing health intervention strategies that target reduction of kids’ mortality is imperative.

Begait Goat Production Systems and Breeding Practices in Western Tigray, North Ethiopia

A study was undertaken to characterize production system, breeding practices and production constraints of Begait goat in Kafta humera district, northwestern lowlands of Ethiopia. Personal observations, focus group discussions and a detailed structured questionnaire were used to collect data from 150 respondents (99 small-scale and 51 large-scale farmers). Mixed crop-livestock production system was found to be the dominant farming system in the study district. The farmers kept a variety of livestock species including goats, sheep, cattle, chickens and donkeys. Small ruminants are the most numerous and are of great importance in the area. Goats are herded with sheep in the open fields by the young boys in the family/hired grazers. They have a number of roles though mainly kept as a source of cash income. Breeding was generally uncontrolled. Size, growth rate and libido were the most frequently reported traits in selecting bucks, whereas does were selected based on size, twining ability and milk yield. Effective population size and rate of inbreeding were calculated by considering random mating and flocks were not mixed. The major constraints hampering goat production in the area were water scarcity, feed and grazing land shortages and insufficient veterinary services among the others. Therefore, addressing these constraints is important to design a successful genetic improvement scheme in the area for goat.

Nitrogen fertilization effects on grain quality of durum wheat (<i>Triticum turgidum</i>L. var. durum) varieties in central Ethiopia

Four released durum wheat varieties, two medium tall (Arsi-Robe and Kilinto) and two recently released semidwarfs (Ude and Yerer) were evaluated under five different N rates (0, 60, 120, 180 and 240 kg·ha-1) in 2005/06 growing season at Akaki and Debre Zeit, central Ethiopia. The quality responses of durum wheat varieties to different N-fertilizer rates and the N responses between tall and short durum wheat varieties were assessed. Protein and gluten content, vitreous kernel count, thousand kernel weight, test weight and lodging were considered. Vitreous kernel count, protein and gluten content were higher at Debre Zeit than at Akaki. Unlike Debre Zeit, there were significant relationships between response variables and fertilizer levels at Akaki. Lodging slightly affected the medium tall varieties at Debre Zeit whereas it was not a problem at Akaki. At Akaki, varieties response to each additional N rate was entirely below the quality standard set by ICC, 2000 except for thousandkernel weight. Therefore, it is unwise to promote durum wheat scaling up/out program for quality production at Akaki.

Observed and Future Spatiotemporal Changes of Rainfall Extreme Characteristics and Their Dynamic Driver in June-August Season over Africa

Climate change has increased extreme events over globe and the most robust occurrences of concurrent drought and floods have become more common in Africa. This study focuses on the observed and projected analysis of rainfall extremes of consecutive dry day (CDD) and maximum monthly five day precipitation (RX5day) from Expert Team on Climate Change Detection and Indices (ETCCDI) in June-August season over Africa. The daily CORDEX Africa, reanalysis and CRU datasets were analyzed for extreme trends under RCP4.5 and RCP8.5 scenarios for the periods of 1980 to 2100. The spatiotemporal variability, trend, and magnitude of JJA seasonal rainfall performance exhibits a significant decreasing tendency over Eastern Africa compared to West Africa. The observed results of consecutive dry day (CDD) reveal that increasing trend and moreover RX5day shows that promising positive trend. Both rainfall extremes are influenced by the combined effect of large scale indexes and appear to be correlated negatively and positively with ENSO, NAO and AO. The CORDEX ensemble mean projections of JJA seasonal rainfall performance show a widespread significant change and the first mode of EOF depicts that 13.8% and 24.9% under the RCP4.5 and the highest variability is under RCP8.5 scenario. The projected CDD extreme exhibit an increasing trend in the coming periods and the percentage change revealed that increasing from 25.11%, 28.02% over West and 26.49%, 31.66% East Africa under RCP4.5 and RCP8.5 scenarios respectively. This situation will exacerbate increasing of frequent and intensified drought extremes over Africa. Additionally, the future RX5day indicated that mixed trend and revealed that increasing 3.72%, 2.54% over West and decreases -16.12%, -22.47% over East Africa under RCP4.5 and RCP8.5 respectively. Generally, rainfall extremes of CDD are projected to increase and RX5day shows a mixed trend in the coming periods over Africa and calls for further verification by using high resolution datasets.

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.

The advancements,challenges,and future implications of the CRISPR/Cas9 system in swine research

Clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(CRISPR/Cas9)genome editing technology has dramatically influenced swine research by enabling the production of high-quality disease-resistant pig breeds,thus improving yields.In addition,CRISPR/Cas9 has been used extensively in pigs as one of the tools in biomedical research.In this review,we present the advancements of the CRISPR/Cas9 system in swine research,such as animal breeding,vaccine development,xenotransplantation,and disease modeling.We also highlight the current challenges and some potential applications of the CRISPR/Cas9 technologies.

Ecohealth research in Southeast Asia: past, present and the way forward

Ecohealth is a comprehensive approach to understanding health at its human,animal and environmental interface in a socio-ecological systems context.This approach was introduced widely in Southeast Asia(SEA)by the Canadian International Development Research Centre(IDRC)in the late 2000s.Aimed at addressing the problem of emerging infectious diseases(EIDs),numerous such projects and activities have been generated throughout the region.Ecohealth is increasingly converging with the One Health approach,as both movements emphasise a holistic understanding to health.We conducted a scoping review by considering all of the Ecohealth programmes,initiatives and projects that have been implemented in SEA since the introduction of the approach,and also gathered information from peer-reviewed literature.The objective of this paper is to review Ecohealth activities within SEA over the last 10 years to address the lessons learned,challenges faced and the way forward for Ecohealth in the region.Activities range from those focusing purely on capacity,projects focusing on research and projects covering both.Achievements to date include,for example,research contributing to the field of infectious diseases in relation to social ecological factors and associated urbanisation and agricultural intensification.Challenges remain at the project design and implementation level,in the available capacity and coordination to develop Ecohealth research teams in the countries,gauging teams’assimilation of Ecohealth’s underlying tenets and their translation into sustainable disease prevention and control,as well as in the ability to scale up Ecohealth projects.We suggest that the way forward for Ecohealth should be from a regional perspective in terms of research,training and policy translation using Ecohealth in combination with the One Health approach.

Sustainable land management interventions lead to carbon sequestration in plant biomass and soil in a mixed croplivestock system:the case of Geda watershed,central highlands of Ethiopia

Background:Sustainable land management interventions were introduced in Geda watershed in 2012 to reduce soil erosion,improve water infiltration,and increase plant-carbon inputs into the soil.This study explored the impact of the interventions on biomass production,carbon stock,and carbon sequestration.Stratified sampling was employed in the main and the dry seasons in the treated and untreated sub-watersheds that are found adjacent to each other.Above-and below-ground plant biomass,soil bulk density and organic carbon in 0-15-and 15-30-cm depths,and soil moisture content in 0-20-and 20-40-cm depths were collected from the crop,grazing,and tree lucerne plots.All analyses were performed based on standard procedures.Results:Plant biomass production,carbon stock,and carbon sequestration varied highly significantly(P≤0.001)among sub-watersheds,landscape positions,and land uses.Higher mean values were observed for treated subwatershed,lower landscape position,and tree lucerne plot.The higher mean values in the lower landscape position of the treated sub-watershed were due to tree lucerne plantation.Similarly,topsoil(0-15 cm)carbon stock was statistically higher(P≤0.001)in the treated sub-watershed and at tree lucerne plot(P≤0.05).In addition,carbon stock by sub-surface soil(15-30 cm)was significantly higher(P≤0.001)in the treated sub-watershed under crop and grazing lands but the higher value was in cropland and in the upper position.This could be due to the decomposition of organic materials from biomasses of crops and biological supporting measures(tree lucerne and Phalaris)facilitated by tillage.Six years of sustainable land management interventions led to the sequestration of 12.25,7.77,and 13.5 Mg C ha^(−1) under cropland,tree lucerne,and grazing plots,respectively.Conclusion:Sustainable land management interventions revealed auspicious ecological impacts in Geda watershed in terms of improving plant biomass production,carbon stock,and correspondingly capturing higher carbon dioxide equivalent taking untreated sub-watershed as a baseline.Prohibition of free grazing was the key element of the intervention to reduce biomass export and increase carbon sequestration in the treated sub-watershed.Thus,sustaining tree lucerne plants as a conservation measure and the prohibition of free grazing practices are principally essential.

Competition for land resources:driving forces and consequences in crop-livestock production systems of the Ethiopian highlands

Introduction:Ethiopia has made efforts to tackle the challenges of low crop and livestock productivity and degradation of land resources through various rural development strategies.However,increasing demands for food,animal feed,fuel,and income-generating activities are putting pressure on the land.In this paper,we describe the production pressure and competition between crop and livestock production,quantify rates of land-use/cover(LULC)changes,and examine driving forces and consequences of land conversion.Methods:The study was conducted in Gudo Beret watershed,North Shewa Zone of Amhara region,Ethiopia.It used a combination of methods including remote sensing,household interviews,field observations,focus group discussions,and key informant interviews.Supervised and unsupervised image classification methods were employed to map LULC classes for 31 years(1984–2016).Results:The results of satellite remote sensing revealed that 51%of the land in the study area was subject to accelerated land conversions.The household survey results indicated that feed resources and grain production pressures were 1.43 and 1.34 t ha^(−1) respectively.The observed annual changes in plantation and settlement areas were 2.6%and 2.9%.This was mainly at the expense of bushland and grazing land systems.Cropland increased(0.4%year^(−1))while grazing land reduced(3.5%year^(−1))under contrasting dynamics and competitive changes.An increase in human and livestock populations and farm expansion were major drivers of land conversion that adversely affected household livelihoods and the natural ecosystem.The consequences of these pressures resulted in a lack of animal feed,low crop-livestock productivity,and a reduction in natural vegetation coverage.Conclusions:We suggest that sustainable land resource management,more integrated crop-livestock production,and the use of productivity-enhancing technologies could play a role in managing competition for land resources.

Food safety in Vietnam:where we are at and what we can learn from international experiences

Food-borne diseases are attracting a lot of attention in Vietnam as a result of repeated episodes of adulterated and unsafe food.In this paper,we provide some perspectives on food safety in Vietnam from the point of view of an international research institution working on food safety with partners in the country.We argue that one of the key issues of food safety in Vietnam is that certain food value chain stakeholders lack ethics,which leads to the production and trading of unsafe foods in order to make profits irrespective of adverse health effects on consumers.In turn,the shortfall in ethical behaviours around food can be attributed to a lack of incentives or motivating factors.Although food safety causes panic in the population,it is unclear how much contaminated food contributes to the burden of food-borne diseases and food poisonings in Vietnam.However,globally,the biggest health problem associated with food are infections from consuming food contaminated with viruses,bacteria or parasites.A major food safety challenge is the inappropriate way of communicating food risks to the public.Another key constraint is the inherent difficulty in managing food in wet markets and from smallholder production.On the other hand,local foods,and local food production and processing are an important cultural asset as well as being essential to food safety,and these aspects can be put at risk if food safety concerns motivate consumers to purchase more imported foods.In this paper,we also discuss good experiences in food safety management from other countries and draw lessons learnt for Vietnam on how to better deal with the current food safety situation.

SUSTAINABLE DEVELOPMENT OF CROP-LIVESTOCK FARMS IN AFRICA

Crop-livestock farms across Africa are highly variable due to in agroecological and socioeconomic factors,the latter shaping the demand and supply of livestock products.Crop-livestock farms in Africa in the 20-first century are very different from most mixed farms elsewhere in the world.African crop-livestock farms are smaller in size,have fewer livestock,lower productivity and less dependency on imported feed than farms in most countries of Europe,the Americas and the intensive agricultural systems of Asia.This paper discusses the role African crop-livestock farms have in the broader socio-agricultural economy,and how these are likely to change adapting to pressures brought on by the intensification of food systems.This intensification implies increasing land productivity(more food per hectare),often leading to more livestock heads per farm,producing fertilized feeds in croplands and importing feed supplements from the market.This discussion includes(1)the links between crop yields,soil fertility and crop-livestock integration,(2)the increasing demand for livestock products and the land resources required to meet to this demand,and(3)the opportunities to integrate broader societal goals into the development of crop-livestock farms.There is ample room for development of crop-livestock farms in Africa,and keeping integration as part of the development will help prevent many of the mistakes and environmental problems related to the intensification of livestock production observed elsewhere in the world.This development can integrate biodiversity,climate change adaptation and mitigation to the current goals of increasing productivity and food security.The inclusion of broader goals could help farmers access the level of finance required to implement changes.

ABE-induced PDGFD start codon silencing unveils new insights into the genetic architecture of sheep fat tails

Sheep is an important livestock species raised globally to produce meat,milk,wool,and other by-products.During the Neolithic Revolution,sheep were domesticated in the Fertile Crescent of Southwest Asia around 10,000 years ago(Chessa et al.,2009).

Global dispersal and adaptive evolution of domestic cattle:a genomic perspective

Domestic cattle have spread across the globe and inhabit variable and unpredictable environments.They have been exposed to a plethora of selective pressures and have adapted to a variety of local ecological and management conditions,including UV exposure,diseases,and stall-feeding systems.These selective pressures have resulted in unique and important phenotypic and genetic differences among modern cattle breeds/populations.Ongoing efforts to sequence the genomes of local and commercial cattle breeds/populations,along with the growing availability of ancient bovid DNA data,have significantly advanced our understanding of the genomic architecture,recent evolution of complex traits,common diseases,and local adaptation in cattle.Here,we review the origin and spread of domestic cattle and illustrate the environmental adaptations of local cattle breeds/populations.

Seasonal and geographical distribution of bacillary dysentery(shigellosis)and associated climate risk factors in Kon Tum Province in Vietnam from 1999 to 2013

Background:Bacillary dysentery(BD)is an acute bacterial infection of the intestine caused by Shigella spp.,with clinical symptoms ranging from fever to bloody diarrhoea to abdominal cramps to tenesmus.In Vietnam,enteric bacterial pathogens are an important cause of diarrhoea and most cases in children under 5 years of age are due to Shigella strains.The serogroups S.flexneri and S.sonnei are considered to be the most common.The main objective of this study was to,for the first time,assess the seasonal patterns and geographic distribution of BD in Vietnam,and to determine the climate risk factors associated with the incidence of BD in Kon Tum Province,where the highest rate of bacillary dysentery was observed from 1999 to 2013.Methods:The seasonal patterns and geographic distribution of BD was assessed in Vietnam using a seasonaltrend decomposition procedure based on loess.In addition,negative binomial regression models were used to determine the climate risk factors associated with the incidence of BD in Kon Tum Province,from 1999 to 2013.Results:Overall,incidence rates of BD have slightly decreased over time(except for an extremely high incidence in 2012 in the north of Vietnam).The central regions(north/south central coast and central highlands)had relatively high incidence rates,whereas the northwest/east and Red River Delta regions had low incidence rates.Overall,seasonal plots showed a high peak in the mid-rainy reason and a second smaller peak in the early or late rainy season.The incidence rates significantly increased between May and October(“wet season”)across the country.In Kon Tum Province,temperature,humidity,and precipitation were found to be positively associated with the incidence of BD.Conclusions:Our findings provide insights into the seasonal patterns and geographic distribution of BD in Vietnam and its associated climate risk factors in Kon Tum Province.This study may help clinicians and the general public to better understand the timings of outbreaks and therefore equip them with the knowledge to plan better interventions(such as improving water,sanitation,and hygiene conditions)during peak seasons.This can,in turn,prevent or reduce outbreaks and onwards transmission during an outbreak.

Comparison of Extrapolation and Interpolation Methods for Estimating Daily Photosynthetically Active Radiation(PAR)——A Case Study of the Poyang Lake National Nature Reserve,China

Measurements of photosynthetically active radiation(PAR),which are indispensable for simulating plant growth and productivity,are generally very scarce.This study aimed to compare two extrapolation and one interpolation methods for estimating daily PAR reaching the earth surface within the Poyang Lake national nature reserve,China.The daily global solar radiation records at Nanchang meteorological station and daily sunshine duration measurements at nine meteorological stations around Poyang Lake were obtained to achieve the objective.Two extrapolation methods of PARs using recorded and estimated global solar radiation at Nanchang station and three stations(Yongxiu,Xingzi and Duchang) near the nature reserve were carried out,respectively,and a spatial interpolation method combining triangulated irregular network(TIN) and inverse distance weighting(IDW) was implemented to estimate daily PAR.The performance evaluation of the three methods using the PARs measured at Dahuchi Conservation Station(day number of measurement = 105 days) revealed that:(1) the spatial interpolation method achieved the best PAR estimation(R 2 = 0.89,s.e.= 0.99,F = 830.02,P < 0.001);(2) the extrapolation method from Nanchang station obtained an unbiased result(R 2 = 0.88,s.e.= 0.99,F = 745.29,P < 0.001);however,(3) the extrapolation methods from Yongxiu,Xingzi and Duchang stations were not suitable for this specific site for their biased estimations.Considering the assumptions and principles supporting the extrapolation and interpolation methods,the authors conclude that the spatial interpolation method produces more reliable results than the extrapolation methods and holds the greatest potential in all tested methods,and more PAR measurements should be recorded to evaluate the seasonal,yearly and spatial stabilities of these models for their application to the whole nature reserve of Poyang Lake.

Groundwater recharge rates and surface runoff response to land use and land cover changes in semi-arid environments

The effects of land use and land cover(LULC)on groundwater recharge and surface runoff and how these are affected by LULC changes are of interest for sustainable water resources management.However,there is limited quantitative evidence on how changes to LULC in semi-arid tropical and subtropical regions affect the subsurface components of the hydrologic cycle,particularly groundwater recharge.Effective water resource management in these regions requires conclusive evidence and understanding of the effects of LULC changes on groundwater recharge and surface runoff.We reviewed a total of 27 studies(2 modeling and 25 experimental),which reported on pre-and post land use change groundwater recharge or surface runoff magnitude,and thus allowed to quantify the response of groundwater recharge rates and runoff to LULC.Comparisons between initial and subsequent LULC indicate that forests have lower groundwater recharge rates and runoff than the other investigated land uses in semi-arid tropical/subtropical regions.Restoration of bare land induces a decrease in groundwater recharge from 42% of precipitation to between 6 and 12% depending on the final LULC.If forests are cleared for rangelands,groundwater recharge increases by 7.8±12.6%,while conversion to cropland or grassland results in increases of 3.4±2.5 and 4.4±3.3%,respectively.Rehabilitation of bare land to cropland results in surface runoff reductions of between 5.2 and 7.3%.The conversion of forest vegetation to managed LULC shows an increase in surface runoff from 1 to 14.1% depending on the final LULC.Surface runoff was reduced from 2.5 to 1.1% when grassland is converted to forest vegetation.While there is general consistency in the results from the selected case studies,we conclude that there are few experimental studies that have been conducted in tropical and subtropical semi-arid regions,despite that many people rely heavily on groundwater for their livelihoods.Therefore,there is an urgent need to increase the body of quantitative evidence given the pressure of growing human population and climate change on water resources in the region.

Was chicken domesticated in northern China?New evidence from mitochondrial genomes

The timing and location of chicken(Gallus gallus domesticus)domestication have remained controversial for over a century[1].Several researchers have proposed China as one of the early centers for chicken domestication[2].This is based on a few archaeological‘‘chicken"remains discovered in China(Table S1).Recently,one investigation detected mitochondrial DNA(mt DNA)haplotypes