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The northern Tibetan Plateau is the most traditional and important semi- nomadic region in Tibet. The alpine vegetation is sensitive and vulnerable to climate change and human activities, and is also important as an ecological security in protecting the headwaters of major rivers in Asia. Therefore, the Tibetan alpine grasslands have fundamental significance to both Mainland China and South Asia. The pasture degradation, however, likely threatens the livelihood of residents and the habitats of wildlife on this plateau. Since 2004, the government has launched a series of ecological restoration projects and economic compensatory payment polices. Many fences were additionally built on degraded pastures to prevent new degradation, to promote functionality recovery, and to balance the stocking rate with forage productivity. The grazed vs. fenced paired pastures across different zonal grassland communities along evident environmental gradients provide us with a natural comparative experiment platform to test the relative contributions of natural and anthropogenic factors. This study critically reviews the background, significance of and debates on short-term grazing exclusion with fences in this region. We also aim to figure out scientific and standardized workflows for assessing the effectiveness of grazing exclusion and compensatory payments in the future. View Full-Text

South Cambridgeshire has some of the richest arable land in England and has been cultivated for millennia. By the turn of the nineteenth century industrialisation and massive population growth had resulted in an enormous increase in the demand for food, which in turn led to enclosure. But this desire to plough every available piece of land resulted in the destruction of many valuable and distinctive habitats that had existed for centuries. The Ecology of Enclosure breaks new ground in comparing the effect of Parliamentary Enclosure with the findings of the enthusiastic 'Botanisers' from Cambridge; this reveals not only the effect of enclosure on the ecology of the land but also on the people whose link with the land was broken. The first section presents a study of social and agricultural life before enclosure, describing geology and climate; the fold-course open field system of farming and the strict stinting rules which governed how land could be used for grazing and stock movement; and the crop rotation systems employed. The second part describes the process of enclosure, including opposition to it; the changes that occurred to the landscape and within village communities as work in industry gradually replaced rural occupations; the effects of fencing on movement; and of the loss of common land to the plough. The third section is an analysis of the new study of Botany which the University of Cambridge was enjoying in the eighteenth and nineteenth centuries based on their own records and a review of some of the specific effects on the flora and fauna of the area.

Pastoral mobility is seen as the most effective strategy to make use of constantly shifting resources. However, mobile pastoralism as a highly-valued strategy to manage grazing areas and exploit resource variability is becoming more complex, due to recurrent droughts, loss of forage, government-led settlement schemes, and enclosure of land for community conservation, among other reasons. Yet knowledge of how Samburu pastoralists perceive these changes, and govern and innovate in their mobility patterns and resource use, has received limited attention. This paper seeks to understand how Samburu pastoralists in the drylands of northern Kenya use and govern natural resources, how livestock grazing and mobility is planned for, and how boundaries and territory are constructed and performed both within and beyond the context of (non)governmental projects. Fieldwork for this paper was conducted in Sesia, Samburu East, and consisted of interviews, focus group discussions, and participatory observation. Findings show that livestock mobility involves longer periods and more complex distances due to a shrinking resource base and new rules of access. Although access was previously generated based on the value of reciprocity, the creation of new forms of resource management results in conditional processes of inclusion and exclusion. Policy and project implementation has historically been driven by the imperative to secure land tenure and improve pasture in bounded areas. Opportunities to support institutions that promote mobility have been given insufficient attention. ; This work was supported by the Marie Skłodowska-Curie Actions Resilience in East African Landscapes (REAL) Innovative Training Network funded by the European Commission [FP7-PEOPLE-2013-ITN project no. 606879]. ; Resilience in East African Landscapes

In recent years, the continued loss and fragmentation of steppe has caused decreased ecosystem functions and species losses in insect diversity. In the 2000s, the Chinese government developed a series of national projects, such as the construction of enclosures, to conserve natural ecosystems, including steppe. However, the effects of these enclosures on steppe arthropod community are largely unknown. In the present study, we selected enclosed and low‐grazing regions at eight National Grassland Fixed Monitoring Stations to examine the compositional differences in four insect functional groups and their associated ecological functions. The results showed that diversity significantly differed between the enclosed and low‐grazing regions, with the number of insect families being significantly higher in enclosed regions than in regions with low‐grazing pressure. The responses of the insect community to steppe management also varied among the four groups (herbivores, predators, parasitoids, and pollinators). The abundances of herbivores, predators, and parasitoids were higher in enclosed regions than in low‐grazing regions, while there was no significant difference in pollinators. Additionally, there were no significant differences in the predator/prey ratio between enclosed regions and low‐grazing regions in any of the steppe types. The parasitic wasp/prey ratio was higher in enclosed regions than in low‐grazing regions in meadow steppe and typical steppe, while there were no significant differences between the enclosed and low‐grazing regions in desert steppe and steppe desert. Herbivores were observed to benefit much more from enclosures than predators, parasitoids, and pollinators. Therefore, we recommend low‐grazing should be considered in steppe conservation, which could conserve biodiversity and achieve biocontrol functions of arthropod community.

There are few comprehensive surveys addressing the evolution of China's grassland policies, particularly with respect to fencing. As a necessary prologue to such an inquiry, this paper presents the national-level laws and regulations that have structured contemporary property regimes and affected the rate and extent of the enclosure movement in pastoral western China, with a focus on Tibetan areas. Based on this review of the legal and political framework of enclosure on the Tibetan Plateau, I will argue that the intent and sequencing of development policies in pastoral areas has been based on the overriding logic of modernization, privatization, and intensification (Yeh 2005). This logic, in turn, has been used to promote enclosure and rationalize heavy investments in technologies of control – policies that reflect the state's political goals in Tibetan areas and which may have unintended consequences, including increased grazing pressure on, and degradation of, the very rangeland resources that are putatively being protected by enclosures. Rather than addressing critical socio-economic constraints in pastoral areas such as population pressures and market distortions (Shen 2004), policy makers have focused instead on technical interventions (e.g., reseeding, improving the genetics of livestock breeds) without recognizing the integrated nature of the challenges confronting Tibetan pastoralists amidst ongoing and rapid shifts in their socio-economic situation.

Context
When measuring grazing impacts of vertebrates, the density of animals and time spent foraging are important. Traditionally, dung pellet counts are used to index macropod grazing density, and a direct relationship between herbivore density and foraging impact is assumed. However, rarely are pellet deposition rates measured or compared with camera-trap indices.

Aims
The aims were to pilot an efficient and reliable camera-trapping method for monitoring macropod grazing density and activity patterns, and to contrast pellet counts with macropod counts from camera trapping, for estimating macropod grazing density.

Methods
Camera traps were deployed on stratified plots in a fenced enclosure containing a captive macropod population and the experiment was repeated in the same season in the following year after population reduction. Camera-based macropod counts were compared with pellet counts and pellet deposition rates were estimated using both datasets. Macropod frequency was estimated, activity patterns developed, and the variability between resting and grazing plots and the two estimates of macropod density was investigated.

Key Results
Camera-trap grazing density indices initially correlated well with pellet count indices (r2=0.86), but were less reliable between years. Site stratification enabled a significant relationship to be identified between camera-trap counts and pellet counts in grazing plots. Camera-trap indices were consistent for estimating grazing density in both surveys but were not useful for estimating absolute abundance in this study.

Conclusions
Camera trapping was efficient and reliable for estimating macropod activity patterns. Although significant, the relationship between pellet count indices and macropod grazing density based on camera-trapping indices was not strong; this was due to variability in macropod pellet deposition rates over different years. Time-lapse camera imagery has potential for simultaneously assessing herbivore foraging activity budgets with grazing densities and vegetation change. Further work is required to refine the use of camera-trapping indices for estimation of absolute abundance.

Implications
Time-lapse camera trapping and site-stratified sampling allow concurrent assessment of grazing density and grazing behaviour at plot and landscape scale.

Context
Grazing pressure has directly altered and indirectly influenced natural ecosystems worldwide, and has affected and displaced many native species. The endangered pygmy bluetongue lizard Tiliqua adelaidensis is endemic to the mid-north of South Australia. It inhabits remnant native grasslands where it is reliant on the presence of natural spider burrows constructed by lycosid and mygalomorph spiders as refuge sites. These lizards spend the majority of the day associated with their burrow either in the burrow itself or basking at its entrance. The remnant native grasslands of South Australia have endured 200 years of agricultural changes and the introduction of domestic stock has meant that grazing pressure has substantially increased. The vegetation around a burrow is considered to be important in providing shelter for the lizard. However, too much vegetation may reduce basking opportunities and visibility of prey. Stock grazing has been maintained on the majority of sites that contain pygmy bluetongue populations and it is presumed that the lizards can tolerate some form of grazing. However, the level of grazing intensity directly influences the vegetation structure that surrounds the lizard burrows.

Aims
We aimed to investigate the consequences of severe grazing pressure on the choice of burrows by lizards, and on their burrow related behaviour.

Methods
We simulated heavy grazing pressure by manually removing aboveground vegetation in the field in replicated quadrats that contained artificial burrows, and by providing bare substrate in half of experimental enclosures in the laboratory.

Key results
In the field, lizards only occupied the artificial burrows in control quadrats, where vegetation had been left intact. In the laboratory, lizards that occupied both burrows basked for longer at the burrow entrance where vegetation was present.

Conclusions
Heavy grazing management that results in the majority of vegetation being removed could have a negative impact on pygmy bluetongue lizard recruitment and sustainability.

Implications
Grazing regimes should be carefully monitored to consider the needs of species that rely heavily on microhabitat structure for their persistence. For the endangered pygmy bluetongue lizard, heavy grazing should be avoided to promote amounts of vegetation suitable to sustain viable populations.

This paper outlines a technique for estimating, by means of faecal pellet counts, the absolute number
of eastern grey kangaroos, Macropus giganteus, grazing on a given area in the A.C.T. Absolute numbers
were obtained by comparing relative density of pellets on the area to be assessed, with pellet density
in the grey kangaroo enclosure at Tidbinbilla Nature Reserve, which has a known area and a known
kangaroo population. The decay rate of pellets in three different areas did not vary significantly.
The average number of pellets per pellet group was similar in all three areas, but during drought kangaroos
tended to drop fewer pellets per group. However, the potential error caused by this can be avoided if
the control and test areas are assessed at the same time. The problem of defining a group is eliminated
by counting individual pellets rather than groups.

Pastoral mobility is seen as the most effective strategy to make use of constantly shifting resources. In northern Kenya, mobile pastoralism as a highly-valued strategy to manage grazing areas and exploit resource variability is becoming more complex. Policy and project implementation has historically been driven by the imperative to secure land tenure and improve pasture in bounded areas through State-led settlement schemes. Relatively recently, increased (inter)national interests in nature and wildlife conservation on community land in the northern pastoralist regions see conservation and development as crucial and urgent requirements for stimulating economic growth and security. This study presents the case of Samburu pastoral mobility within the context of such shifting social and environmental circumstances. It focuses on changing rules of access and control of livestock resources. These transformations are analysed in the context of the large-scale establishment of community conservancies and what role these conservancies play in the actual use and transformation of space for pastoralists. Empirically, this thesis is based on a total of eighteen months fieldwork including semi-structured interviews and observations in Samburu, Isiolo and Laikipia. It demonstrates how the principal of reciprocal access to pasture between pastoralists is giving way to conditional access based on membership of more formal, territory-based institutions such as community conservancies. It further shows how access to private land may be open for negotiation through the formation of grazing arrangements, which are also used to control pastoralists' movements beyond enclosed land. In spite of a rhetoric acknowledging the multiple benefits of livestock mobility, current policy entails a continuation of past policy and project implementation where prescriptions still revolve around conservation enclosures and settlement politics. The thesis concludes that such processes of territoriality are likely to produce unexpected and potentially disappointing outcomes, while struggle and conflict persist. ; At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 3: Manuscript.

Pitfall traps are commonly used to capture terrestrial vertebrates, but it is not known whether differences in vegetation structure affect the efficiency of these traps. Studies that investigate the effects of fire, grazing or vegetation rehabilitation on faunal populations usually compare sites that differ in vegetation structure and the validity of using pitfall traps to sample populations under these circumstances is open to question. This study tests whether vegetation structure affects the rate at which lizards are captured in pitfall traps by cutting ground vegetation in a controlled experiment conducted in field enclosures. The study was undertaken in an area of mulga (Acacia aneura) shrubland in central Australia. Ground cover, consisting of grasses and forbs, was reduced from ~27% to 10% in treatment enclosures. These levels of cover correspond broadly to the range of ground covers encountered in this habitat, including areas with high and low levels of grazing. No difference was detected in the rate at which lizards were captured in enclosures where grass was cut compared with the control enclosures or rates of capture before grass was cut. These results indicate that pitfall trapping is a valid technique for comparing lizard populations in arid mulga shrublands within the range of vegetation covers used in this study, including areas that are subject to different levels of grazing.

Transhumant pastoralism in north-central Namibia, the former Owambo, was explored from a historical perspective, using the theory of socio-environmental history as a framework. The study used secondary data, informal interviews and discussions, and for recent times, interviews with herders. The change or transformation of transhumant pastoralism in Ohangwena was analysed from three phases, namely, the period before colonialism, during colonialism and after Independence. The goal was to understand how transhumance has been transformed over the years and factors responsible for such transformations. The study shows that livestock mobility in north-central Namibia involved nearly 70-90 per cent of cattle in transhumant migrations. However, the transhumance has changed in scope and extent of movements at geographical scales over the periods under consideration from 1900 to 2006. Some of the traditional routes of migrations have been retained. Since colonial times, particularly during the German rule in Namibia, the changes in transhumant pastoralism were more to man-made than natural causes. During the colonial administration Owambo pastoralism was never understood. In combination with other factors such as political factors, this led to the neglect of agriculture and pastoralism in the north-central regions. The change in livestock mobility is mainly connected to the decrease in rangeland size and communal grazing, the change in communal land rights, introduction of new cattle breeds, adoption of new cattle ranching methods and shortage of professional herdsmen. The rangeland has decreased mainly due to establishment of clearly-defined artificial borders, animal control-fences such as veterinary cordon fence (VCF), introduction of sedentary agriculture in previously grazing reserves, the change in patterns of human settlements and so forth. The change in communal grazing, which has decreased by 20 per cent, and grazing rights is mainly caused by the development and extension of modern infrastructures such as water pipelines, the privatization (enclosures) of large areas of communal land, and weakened power and capacity of traditional rulers on management of grazing and land. The migration of men mainly for formal paid jobs and participation in war has contributed to the shortage of Owambo professional herdsmen to implement transhumant migrations. Since communal grazing and the rangeland have decreased, transhumant pastoralists have been experiencing difficulties with regards to sufficient grazing and livestock mobility. Conflicts associated with grazing resources have become common in the northern Namibia because of more demands for private land and competition for scarce resources among different land users. Land-related conflicts have affected relationships between different ethnic groups and territories or regions. In the long term this can easily result in the politicization of land-related conflicts which in turn can affect the relationship between poor herders and the elites particularly political elites (whose aim is the privatization of land), and the relationship between pastoralists and the state. Environmental conditions will also be affected if future decisions are unfavourable for transhumant pastoralism. ; M-MNRSA

ABSTRACTTraditional pastoralist land management institutions in sub-Saharan Africa have been stressed by an increasing human population and related forces, including private enclosure of grazing land; government-sponsored privatization; and the increasing prevalence of violent conflicts and livestock theft. We model the incompleteness and flexibility of traditional grazing rights using fuzzy set theory. We compare individual and social welfare under the traditional system to individual and social welfare under a private property system and a common property system. Whether the traditional system is preferred to private property depends on whether the value of mobility, as defined by the traditional system, is more valuable than the right of exclusion inherent in private property. We find that under some conditions the imprecision which characterizes traditional rights can result in higher social returns than a common property regime characterized by complete symmetric rights across all members of the user group and complete exclusion of non-members.

Este artículo contiene 17 páginas, 6 figuras, 3 tablas. ; The stress-gradient hypothesis predicts that biotic interactions within food webs are context dependent, since environmental stressors can attenuate consumer–prey interactions. Yet, how heavy metal pollution infuences the impacts of predatory fsh on ecosystem structure is unknown. This study was conducted in the Osor stream (Spain), which features a metal (mainly Zn) pollution gradient. We aimed to determine how the responses of benthic communities to the presence and absence of predatory fsh interact with environmental stress and to test whether the top-down control of top predators is context dependent. To address these questions, periphyton biomass and macroinvertebrate densities were determined throughout an exclosure/ enclosure mesocosm experiment using the Mediterranean barbel (Barbus meridionalis) as a top predator. The monitoring study showed that metal accumulation in periphyton and macroinvertebrates refected patterns observed in water. The mesocosm study showed that fsh predation efects on larval chironomids were not context-dependent and that periphyton biomass was markedly lower in the presence of fsh regardless of metal pollution levels. This strong top-down control on periphytic algae was attributed to the foraging behaviour of fsh causing bioturbation. In contrast, the top predator removal revealed grazer-periphyton interactions, which were mediated by heavy metal pollution. That is, periphyton beneftted from a lower grazing pressure in the metal-polluted sites. Together, our results suggest that the top–down control by fshes depends more on functional traits (e.g. feeding behaviour) than on feeding guild, and demonstrate the capacity of top predators to modify anthropogenic stressor efects on stream food-web structure. ; Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This research was supported by the Spanish Ministry of Science, Innovation and Universities (projects CGL2013‐43822‐R and CGL2016‐80820‐R, AEI/FEDER/EU) and the Government of Catalonia (ref. 2017 SGR 548 and CERCA Programme). F. Rubio‐Gracia and M. Argudo beneftted from a predoctoral fellowship from the University of Girona (IFUdG2017) and the Agency for Management of University and Research Grants (AGAUR) of the Government of Catalonia (2016 FI-B 00284), respectively. ; Peer reviewed

The stress-gradient hypothesis predicts that biotic interactions within food webs are context dependent, since environmental stressors can attenuate consumer-prey interactions. Yet, how heavy metal pollution influences the impacts of predatory fish on ecosystem structure is unknown. This study was conducted in the Osor stream (Spain), which features a metal (mainly Zn) pollution gradient. We aimed to determine how the responses of benthic communities to the presence and absence of predatory fish interact with environmental stress and to test whether the top-down control of top predators is context dependent. To address these questions, periphyton biomass and macroinvertebrate densities were determined throughout an exclosure/enclosure mesocosm experiment using the Mediterranean barbel (Barbus meridionalis) as a top predator. The monitoring study showed that metal accumulation in periphyton and macroinvertebrates reflected patterns observed in water. The mesocosm study showed that fish predation effects on larval chironomids were not context-dependent and that periphyton biomass was markedly lower in the presence of fish regardless of metal pollution levels. This strong top-down control on periphytic algae was attributed to the foraging behaviour of fish causing bioturbation. In contrast, the top predator removal revealed grazer-periphyton interactions, which were mediated by heavy metal pollution. That is, periphyton benefitted from a lower grazing pressure in the metal-polluted sites. Together, our results suggest that the top-down control by fishes depends more on functional traits (e.g. feeding behaviour) than on feeding guild, and demonstrate the capacity of top predators to modify anthropogenic stressor effects on stream food-web structure. ; Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This research was supported by the Spanish Ministry of Science, Innovation and Universities (projects CGL2013-43822-R and CGL2016-80820-R, AEI/FEDER/EU) and the Government of Catalonia (ref. 2017 SGR 548 and CERCA Programme). F. Rubio-Gracia and M. Argudo benefitted from a predoctoral fellowship from the University of Girona (IFUdG2017) and the Agency for Management of University and Research Grants (AGAUR) of the Government of Catalonia (2016 FI-B 00284), respectively.

Nel clima riformista del secondo Settecento europeo, il governo sabaudo incen- tiva gli studi per il miglioramento delle condizioni economiche della Sardegna, partendo dall'agricoltura considerata, secondo teorie fisiocratiche del tempo, il mo- tore dello sviluppo. Emerge in maniera evidente la relazione di causa-effetto tra arretratezza e lotte secolari che coinvolgono una pastorizia transumante ed un'agricoltura condotta an- cora con metodi tradizionali, con ampio uso del maggese e scarsa rotazione delle colture. Il sistema di coltivazione è strettamente legato all'uso comunitario delle terre aperte tipico di un sistema feudale che ancora persiste. La soluzione viene individuata nell'eliminazione delle cause, ma la riforma si attua cercando di non ledere i diritti della classe feudale, calando dall'alto nei primi decenni dell'Ottocento una riforma zoppa che, senza alcun significativo investi- mento da parte dello stato e delle istituzioni, prevede la possibilità di recintare le terre sottraendole all'alternanza pascolo-coltura e agli usi collettivi, affermando una proprietà privata imperfetta poiché ancora sottoposta ai vincoli feudali. Gli alti costi delle recinzioni, gli schemi produttivi tradizionali, la stagnazione che caratterizza l'economia sarda, le lotte tra agricoltori e pastori (a cui viene sot- tratto il pascolo), l'assenza di un mercato interno e gli alti costi di trasporto interno ed esterno all'isola non rendono conveniente introdurre innovazioni significative e ciò determina l'insuccesso della riforma. ; A lame reform in Sardinia: The Edict of the Enclosures In the reformist climate of the second European eighteenth century, the Savoy Government encourages studies to improve the economic conditions of Sardinia, starting from the agriculture considered, according to the physiocratic theories of the time, the engine of development. The cause-effect relationship emerges between backwardness and age-old strug- gles involving transhumant pastoralism and agriculture still carried out with tradi- tional methods, with extensive use of fallow and poor crop rotation. The cultivation system is closely linked to the communal use of open lands typ- ical of a feudal system that still persists. The solution is identified in the elimination of the causes, but the reform is im- plemented by trying not to damage the rights of the feudal class, therefore a lame reform that fell from the top in the first decades of the nineteenth century, which, without any significant investment by the state and institutions, provides for the pos- sibility of enclosing the land by subtracting it from pasture-crop alternation and col- lective uses, affirming an imperfect private property as it is still subject to feudal restrictions. The high costs of fences, traditional production schemes, the stagnation that char- acterizes the Sardinian economy, the struggles between farmers and shepherds (to which grazing is subtracted), the absence of an internal market and the high costs of transport inside and outside the island do not make it worthwhile to introduce sig- nificant innovations and this determines the failure of the reform.